Hi-yield Notes in Anatomy

HI-YIELD FACTS IN ANATOMY [from MOORE & USMLE-ANATOMY roadmap] CHAPTER 1 – BASIC STRUCTURES AND CONCEPTS SKELETAL SYSTEM  Composed of 206 individual bones [80 - axial, 126 – appendicular]  Functions: support, attachment, protection, storage [calcium, phosphorus], hemopoiesis Axial skeleton Appendicular skeleton Skull, vertebral column, rib cage, hyoid, Pectoral girdle and pelvic girdle, bones of auditory ossicles the upper and lower extremities BONES – consists of cancellous [spongy] and compact bone Classification Examples Long bones Clavicle, bones of extremities [except carpals, tarsals] Short bones Carpal bones [hand], tarsal bones [foot] Flat bones Ribs, sternum, scapula, calvaria Irregular bones Vertebrae, hip bones, skull bones Sesamoid bones Patella Clinical notes Fracture  Due to trauma or atrophy from either osteoporosis [loss of bone mass] or disuse.  Leads to avascular necrosis [loss of bone tissue caused by disruption of arterial supply] JOINTS – where 2 or more skeletal elements meet [either bone or cartilage]  Innervated according to HILTON’s law [nerves that supply muscles that move a joint also supply the joint and skin] Classification Types Examples Fibrous Sutures Skull Syndesmoses Tibiofibular, tympanostapedial joints Cartilaginous synchondroses Epiphyseal plates, sphenooccipital synchondroses symphysis Pubic symphysis, vertebral joints Synovial Plane/gliding Intercarpal, sternoclavicular, acromioclavicular Hinge/ginglymus Elbow, knee, ankle joints Pivot / trochoid Atlantoaxial, superior and inferior radioulnar Condyloid Metacarpo/metatarsophalangeal,atlantooccipital Ellipsoid Radiocarpal/wrist joint Saddle Carpometacarpal joint of thumb Ball + socket Shoulder and hip joints [aka enarthroidal joint] Clinical notes

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Bursitis – inflammation of bursa results in bursitis w/c may limit movement of a joint.

MUSCULAR SYSTEM Smooth Involuntary, nonstriated In viscera, blood vessels Modulated by autonomic nerves, hormones, or mechanical stimulation

Cardiac Involuntary, striated In myocardium of heart Does not receive direct innervations [contraction is innervated by autonomic n.

Skeletal Voluntary, striated Anywhere in the body

Other structures: Tendon Connects muscle to bone or cartilage Ligament CT band that crosses a joint binding the articulating bones Clinical notes Myasthenia gravis  Antibodies attack acetylcholine receptors resulting in defective neuromuscular transmission.  S/Sx: bilateral ptosis, horizontal diplopia, dysphagia, dysarthria, and weakness in chewing and in musles of facial expression. Proximal limb muscles may be affected. Cardiac and smooth muscle are spared.  Most of them have thymic hyperplasia or thymoma.  Tx: Acetylcholinesterase inhibitors allowing acetylcholine to remain in synaptic cleft longer. Lambert-Eaton syndrome  An immunologic disorder of Ca+ channels in nerves at the end plate  Proximal muscles in limbs are primarliy affected; muscles innervated by CN are spared. Repetitive contractions of affected muscles temporarily increase in strength.  Associated w/ small cell CA of the lung VASCULAR SYSTEM A. Blood vascular system  Functions: carries oxygen, absorbed nutrients and waste products, promotes healing Pulmonary circulation Systemic circulation Transports blood from R side of heart to lungs Transports blood from L side of heart to the and back to L side of heart body [except lungs] and back to R side of heart Facilitates exchange of O2 & CO2 in LUNGS Facilitates exchange of O2 & CO2 in TISSUES R ventricle, pulmonary arteries, capillaries, L ventricle, R atrium, all arteries, capillaries,

veins and L atrium veins [except of pulmonary circulation] ARTERIES – carry blood from heart to all areas of the body Type Functions Examples Elastic Conducting arteries Aorta, pulmonary trunk, common carotid & subclavian A Muscular Distributing arteries All other arteries Arterioles w/ precapillary sphincter Anywhere in the body CAPILLARIES – smallest of the blood vessels, site of exchange between tissues and blood VEINS – carry blood back to heart from peripheral tissues Type Characteristics Venules w/ valves, smallest type, from confluence of several capillaries Small veins w/ valves and smooth muscle in their walls Medium veins w/ valves and connective tissue + smooth muscle Large veins No valves, w/ abundant elastic fibers and smooth muscle Other components:  SINUSOIDS – discontinuous capillaries larger than ordinary capillaries, found in adrenal & pituitary glands, liver, spleen, and bone marrow  PORTAL SYSTEM – system of vessels interposed between 2 capillary beds, includes hepaticportal system and hypophyseal-portal system LYMPHOID SYSTEM  Functions: returns tissue fluids to venous system, provides immunologic defense & route for lymphocytes + absorbed fats, important route for spread of malignant tumor.  All lymph enters the venous system at the junction of internal jugular V. and subclavian V. in the neck via R lymphatic duct on R side and thoracic duct on the L.  Tissues that lack blood vessels also lack lymphatic vessels w/c include: epidermis, cartilage, CNS and thymus. Type Example Functions Lymph Right Receives lymph from R side of head and neck through R jugular lymph vessels lymphatic trunk, R upper extremity thru R subclavian trunk, R thoracic cavity thru R duct bronchomediatinal trunk Lymph Thoracic Receives lymph from most of the body below diaphragm, L and lower R nodes duct posterior intercostals spaces, L side of neck thru L internal jugular trunk, L upper extremity thru L subclavian trunk, and L side of thoracic cavity thru L bronchomediastinal trunk NERVOUS SYSTEM Classificatio Features n Central NS Brain + spinal cord composed of gray matter [myelinated axons and neuroglia], and white matter [neuronal bodies and dendrites + neuroglia] Peripheral NS Afferent [conduct impulses from sensory receptors towards CNS], and efferent / motor neurons [impulses away from CNS to periph. end organ] Somatic NS Control voluntary activities Visceral NS Control visceral activities Other components:  Astrocytes – physical support, repair, K+ metabolism, help maintain BBB. Its marker is GFAP.  Microglia – for phagocytosis  Neuron/nerve cell – functional unit of nervous system, for communication.  Ganglion – collection of neuronal cell bodies outside CNS.  Oligodendrocytes – glial cells that form central myelin for parts of multiple axons in the CNS.  Schwann cells – are glial cells that form peripheral myelin for axons or processes in the PNS.  Ependymal cells – lines inner lining of ventricles  CNS axons do not regenerate if cut while myelinated axons in PNS does regenerate down. Clinical notes Multiple sclerosis  Both sensory and motor systems containing axons w/ myelin formed by oligodendrocytes undergo an inflammatory reaction that impairs or blocks impulse transmission.  Sensory and motor deficits can be seen in all areas of the body.  CN 2/optic nerve is affected because all of the myelin sheaths of its axons are formed by oligodendrocytes. Optic neuritis is the presenting sign.  Corticosteroid administration promotes remission. Guillain-Barre syndrome  Myelin formed by Schwann cells in PNS undergoes acute inflammatory reaction after a respiratory or gastrointestinal illness. This also impairs or blocks impulse transmission.  Motor axons are always affected producing weakness in limbs. Weakness of CN 6 and 7 or respiratory muscles may be seen. Sensory deficits are mild or absent.  Antibodies to peripheral myelin are removed by plasmapheresis or autoimmune attack is blocked by administration of gamma globulin. Patients often completely recover. Schwannomas  Benign encapsulated schwannomas of vestibular nerve [CN 8] may develop affecting hearing and balance. Large acoustic schwannomas may compress facial nerve [CN 7] or trigeminal nerve [CN V].  Bilateral acoustic schwannomas are seen in pxs w neurofibromatosis type 2.

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CRANIAL NERVES - 12 pair’s w/c arise from brainstem: sensory = CN 1, 2, 8; motor = CN 3, 4, 6, 11, 12; mixed = CN 5, 7, 9, 10. [Refer to Netter p. 112]  Some Say Marry Money But My Bride Says Big Brains Matter Most Name Lesions result in Functions CN 1 – olfactory [S] Anosmia Smell CN 2 – optic [S] Anopsia, loss of light reflex w/ Vision, Only nerve affected by multiple CN 3 sclerosis CN 3 – oculomotor [M] Diplopia, external strabismus, EOM: SR, IR, MR, IO, LPS [except LR loss of parallel gaze, ptosis, and SO] loss of near response Accommodation of near vision CN 4 – trochlear [M] Diplopia, difficulty reading, EOM: superior oblique going down stairs, head tilting CN 5 – trigeminal Loss of sensation in skin of Sensation to scalp, face, jaw, oral [mixed] forehead, scalp, cornea, Movements of masticators, facial maxilla, mandible, tongue, loss of blinking reflex, chewing loss CN 6 – abducens [M] Diplopia, internal strabismus, EOM: lateral rectus – adducts eyeball loss of parallel gaze CN 7 – facial [mixed] Mouth drooping, cannot close Facial expression muscles the eye, wrinkle forehead, loss Secretomotor [salivary glands] of blink reflex, hyperacusis, Taste: anterior 2/3 of tongue altered taste, reduction of Visceral sensation: body saliva and other secretions Somatic sensation: ear CN 8 – cochlear Sensorineural hearing loss, Equilibrium [linear & angular Vestibulocochlear [S] loss of balance, nystagmus acceleration], balance, hearing CN 9Loss of sensory limb of GAG Stylopharyngeus muscle glossopharyngeal reflex w/ CN 10 Secretomotor: parotid gland [mixed] Reduction of saliva Taste: posterior 1/3 of tongue Visceral: pharynx, 1/3 of tongue Somatic: tympanic membrane CN 10 – vagus Nasal speech, nasal Pharynx, larynx, soft palate [mixed] regurgitation, palate droop, Cardiac, smooth, glands deviation of uvula away from Taste over epiglottis lesioned nerve, dysphagia, Visceral sensation and reflexes loss of GAG reflex w/ CN 9, Somatic: ear and dura loss of cough reflex, miosis, anhydrosis, & ptosis [Horner’s] CN 11 – accessory Weakness in turning head to Joins vagus to larynx distribution Spinal portion opposite side, shoulder droop, Sternocleidomastoid, trapezius difficulty in combing the hair CN 12 - hypoglossal Tongue deviation on protrusion Intrinsic’/extrinsic tongue m. [except toward leisioned nerve palatoglossus] Clinical notes Olfactory N. lesions  May cause hyposmia, dysosmia or anosmia.  Olfactory deficits may be caused by a fracture of cribriform plate; w/c damages the primary olfactory neurons.  Fracture of cribriform plate may also tear the meninges [of the olfactory bulb and result in CSF rhinorrheadischarge of CSF from the nostrils]. Oculomotor N. lesions  Caused by compression by a herniated part of hemisphere or by a berry aneurysm tend to affect the parasympathetic fibers 1st resulting in a dilated pupil [mydriasis] and suppression of papillary light reflex.  Complete lesion results most dramatically in an inability to adduct eyeball.  Pxs may have external strabismus [laterally deviated eyeball] that results from unopposed contractions of lateral rectus and superior oblique.  It may also result in ptosis; w/c is due to weakness of skeletal motor part of levator palpebrae superioris muscle. Trochlear N. lesions  Results in diplopia, when a px attempts to depress the adducted eye.  Pxs may experience difficulty in reading or difficulty in going down the stairs.  They may tilt their head away from side of the leioned nerve w/c resuts from weakness in the ability to rotate the affected eyeball inward [intorsion]. The head tilt is an attempt to counteract the extorsion by the unopposed inferior oblique and inferior rectus muscles.  A head tilt observed in pxs w/ trochear nerve lesion might be mistaken for torticollis caused by abnormal contractions of sternocleidomastoid muscle. Abducens N. lesions  Result in weakness in the ability to fully abduct the eye. The superior and inferior oblique muscles act to partially abduct the eye. Pxs may have internal strabismus [medially deviated eyeball] because of the unopposed contractions of medial rectus muscle and other adductors innervated by CN 3.  Abducens nerve is MC the 1st nerve to be affected in a thrombosis of cavernous sinus. Hypoglossal N. lesions  Result in deviation of tongue towards side of the injured nerve on protrusion. They may experience dysarthria and difficulty moving a bolus of food from the oral cavity into the oropharynx.

Facial N. reflexes  Blink reflex uses sensory fibers of the ophthalmic division of CN 5 and skeletal motor fibers of facial N. [CN 8]. Causes direct and consensual blink that results from bilateral contraction of orbicularis oculi muscles.  Lacrimal reflex also uses sensory fiber of CN V1 and results in an increase in lacrimal secretions in response to touching the cornea or in response to chemical stimulants.  Taste salivary reflex, stimulation of taste receptors on the anterior 2/3 of tongue may cause an increase in salivary gland secretions. Facial N. lesions  Occur in facial canal and result in Bell’s palsy. Pxs manifest w/ weakness of muscles of facial expression on side of injured nerve. There is weakness in the ability to shut the eye, nasal flaring, and wrinkle the forehead. There is also drooping of corner of the mouth. They may have pain behind the external auditory meatus resulting from involvement of the general sensory fibers of the posterior auricular nerve.  Lesions of facial N. at genicuate ganglion may have alterations in taste sensations [from anterior 2/3 of tongue and palate], a reduction in salivary gland secretions [from submandibular and sublingual glands] and a dry eye [from a reduction of lacrimal secretions].  Hyperacusis [hypersensitivity to loud sounds] may result if nerve to stapedius is affected.  As pxs recover from a facial nerve lesion, they may experience synkinesis, w/c results from misdirected regenerating motor axons.  Distal to stylomastoid foramen, a tumor of the parotid gland may compress muscular branches of facial N. as they traverse the gland and may result in a weakness of muscles of facial expression but no sensory deficits, hyperacusis or alteration of glandular secretions. SPINAL NERVES  Consists of 31 pairs [8 cervical, 12 thoracic, 5 lumbar, 1 coccygeal]  Formed by union of dorsal root and ventral root at intervertebral foramen Other components:  At T1-L2, trunk of spinal nerve contains preganglioninc symphathetic fibers from cell bodies in the intermediolateral cell column of spinal cord  At S2-4, trunk and proximal ventral rami contain preganglioninc parasymphathetic fibers from cell bodies in sacral parasymphathetic nucleus of spinal cord. They leave the ventral rami as pelvic splanchnic nerves [nervi erigentes] AUTONOMIC NERVOUS SYSTEM  Innervates visceral organs [vascular, glandular], motor to cardiac, smooth muscles and glands, it also maintains homeostasis  Above and below T1 to L2-3 levels of spinal cord, there are no more white rami. Divisions Features Symphathetic NS Activates body’s response to stress [fight or flight reponse] Parasymphathetic NS Also called craniosacral flow [from S2-4 spinal cord], part of CN 3,7,9,10, supplies cardiac, smooth and glands but does not [rest or digest] innervate blood vessels [except erectile tissue of ext. genitalia] Autonomic nerve functions: Features SA node AV node Cardiac output Blood vessels Skin, mucosa, salivary glands Radial muscle of iris Sphincter muscle of iris Ciliary muscle Trachea, bronchi, lungs Gastrointestinal structures Internal anal sphincter Urinary bladder Uterus Arrector pili muscles Salivary glands Lacrimal gland, nasal glands Gastrointestinal glands Sweat glands Adrenal medulla Pineal gland Erection Secretion Emission

Sympathetic Increases HR ↑ conduction delay ↑ contractility and velocity of conduction Generally constricts Generally constricts Dilates pupil; mydriasis Relaxes for far vision Relaxes, allows dilation Inhibits Contributes to contraction Inhibits Variable Contracts ↑ viscosity of secretion No direct effect Inhibits Stimulates secretion Simulates secretion Increases synhesis and release of melatonin No direct effect Facilitates

Parasympathetic Decreases HR ↓ conduction delay ↓ contractility and velocity of conduction Generally dilates Little effect Constricts pupil; miosis Contracts Constricts Stimulates peristalsis Contributes to relaxation Contracts Variable No effect Stimulates secretion Stimulates secretion Stimulates Facilitates Facilitates No direct effect

Clinical notes Horner’s syndrome

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 Lesion in either preganglionic or postganglionic sympathetic neurons that innervate sweat glands and blood vessels in face and scalp or 2 smooth muscles in the orbit. The smooth muscle elevates the upper eyelid and dilates the pupil.  S/Sx: anhydrosis [inability to sweat on corresponding side of the face], ptosis [drooping of upper eyelid], miosis [pupil constriction] Shy-Drager syndrome  Degeneration of preganglionic sympathetic and parasympathetic neurons in brainstem and spinal cord and degeneration of neurons in most ganglia. This may be combined w/ loss of other non-autonomic CNS neurons.  S/Sx: impotence, urine retention, dizziness on standing, blurred vision, and inability to sweat. Hirschprung’s disease [aganglionic megacolon]  Failure of neural crest cells either to migrate into the wall of descending colon, sigmoid colon, or rectum or to differentiate into terminal parasympathetic ganglia in these areas.  It results in absence of perisalsis in the affected segment and a distended bowel proximal to that segment. Reflexes – autonomic motor response to a sensory stimulus, examples include: Muscle stretch Muscle spindles in skeletal muscles are stimulated by stretch causing a reflexes reflex contraction of that same muscle Autonomic Sensory stimuli cause reflex contraction of smooth muscle, the secretion of reflexes a gland, or a change in rate and force of contraction of cardiac muscle Cranial nerve Use sensory and motor fibers in 1 or more cranial nerves and include reflex papillary light reflex, blink reflex, gag reflex, and cough reflex. Clinical notes  Reduced sensation [hypesthesia] and altered sensation [paresthesia] are sensory signs.  Weakness [paresis] of skeletal muscles is a motor sign.  Nerve lesions are destructive when nerves are severely compressed or severed, resulting in a loss of abiity of nerves to conduct impulses.  Lesions to sensory fibers result in loss of sensory modality or modalities carried by fibers in that nerve [anesthesia].  Lesions to motor fibers result in paralysis of denervated skeletal muscles. Denervated skeletal muscle fibers exhibit fasciculations [random twitches seen beneath skin] and may atrophy. CHAPTER 2 – UPPER EXTREMITY AXILLA, PECTORAL REGION AND SHOULDER [refer to Neter p. 400] Boundaries of the axilla  Base: axillary fascia and skin of armpit  Apex: clavicle anteriorly, 1st rib medially, superior border of scapula posteriorly  Medial wall: upper rib cage  Lateral wall: intertubercular groove  Anterior wall: pectoralis major and minor muscle  Posterior wall: subscapularis, teres major and latissimus dorsi muscles Boundarie Quadrangular space Triangular space s Lateral Surgical neck of humerus Shaft of humerus Medial Long head of triceps brachii Long head of triceps brachii Superior Teres minor, subscapularis Teres major Inferior Teres major None Quadralateral space  Above: subscapularis [front], teres minor behind]  Below: teres major  Lateral: surgical neck of humerus  Medial: long head of triceps

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Contents: passage for axillary joint

Axillary lymph nodes Name Lateral/ brachial nodes Posterior/ subscapular nodes Pectoral/ anterior nodes Central nodes Apical nodes

Distribution Upper extremity except vessels following cephalic vein Shoulder, trunk, lower neck Breast and anterior chest wall Receives lateral, posterior and pectoral nodes Receives lymph from all other groups

Bones of upper extremities [refer to Netter p. 391-392, 407, and 426] Division Type Features Pectoral Clavicle or MC fractured at middle and lateral third. Only bone to girdle and collar bone undergo intramembranous ossification, 1st to ossify 5-6 wks proximal Scapula or Overlies 2nd-7th ribs humerus shoulder blade Articulates w/ clavicle and humerus

Skeleton at elbow Skeleton of wrist and hand

Distal humerus Proximal radius Proximal ulna Distal radius Distal ulna Phalanges Metacarpals [5] Carpal bones [8]

Accounts for carrying angle in the elbow Where biceps brachii tendon attaches Where triceps brachii tendon attaches w/ dorsal tubercle of LISTER for ext. pollicis longus For articulation w/ articular disc 2 for thumb, 3 for fingers, forms the knucles 2nd metacarpal is the longest Pisiform – last to ossify [10-12 yrs], capitate – 1st to ossify [2-3 mos.] – Some Lovers Try Position That They Can’t Handle Proximal [lat-medial] – scaphoid, lunate, triquetrum, pisiform Distal [lat-medial] – trapezium, trapezoid, capitate, hamate

Clinical notes Clavicular fracture  Commonly fractured at its weakest point between middle third and lateral third.  Middle 2/3 may be elevated by sternocleidomastoid and lateral 3rd may be depressed by weight of the limb or adducted by petoralis major.  The ventral rami of C8-T1 in medial cord of brachial plexus may be lacerated due to fracture. Shoulder trauma to acromioclavicular joint  May be caused by subluxation of aromion at the acromioclavicular joint. The coracocavicular ligament w/c extends from the acromion, prevents dislocation at acromioclavicular joint. Colle’s fracture  Fracture at distal radius may result in avulsion of styloid process from shaft of radius. May exhibit “dinner-fork deformity” as a result of the posterior displacement of the distal radius. Lunate dislocation  MC disLocated carpal bone. Typically dislocated anteriorly into the carpal tunnel. This may cause carpal tunnel syndrome. Scaphoid fracture  MC fractured carpal bone  S/Sx: pain and tenderness localized over anatomic snuffbox. The proximal part of scaphoid may undergo vascular necrosis because blood supply to bone supplies distal part first then proximal. Joints of upper extremity Name of joint Type Sternoclavicular Ball and socket Acromioclavicular Atypical synovial Shoulder Ball and socket [glenohumeral] Elbow Synovial hinge Prox’l radioulnar Synovial pivot Distal radioulnar types of joint Joints of wrist and hand Name of joint Type Radiocarpal Condyloid Midcarpal Plane / ellipsoid Carpometacarpal Saddle type [1st] Metacarpophalangeal Condyloid Interphalangeal Hinge

Features Only joint btw trunk and upper limb Dislocated w/ fall on outstretched hand Supplied by axillary, suprascapular, lat. Pectoral nerves, joins upper extremity to pectoral girdle Strengthened by medial and lateral collateral ligament Annular lig. - Chief ligament of proximal radioulnar jt. Distal radioulnar jt - provide the strongest attachment Features Does not includes the ulna or pisiform bones Allows flexion, extension, abduction and adduction Flexion, extension, abduction, adduction, opposition Flexion, extension, abduction, adduction, rotation Allows only flexion and extension

Veins of upper extremity [refer to Netter p. 400] Location Name of vein Distribution Drainage Superficial Dorsal venous arch Back of hand Cephalic [lateral] and basilic [medial] veins Cephalic veins Lateral forearm Axillary vein Basilic veins Medial forearm Axillary vein Median cubital Cubital fossa Connects cephalic to basilica vein Median antebrachial Middle forearm Deep veins Axillary vein Main venous structure draining the upper extremity, it [brachial + basilic] becomes the subclavian vein at outer border of 1 st rib Arteries of upper extremity [refer to Neter p. 398, 435] Name of artery Features Subclavian A. Branch: thyrocervical trunk w/c divides into:  Suprascapular A.  Transverse cervical A. – deep branch gives rise to dorsal scapular A. Axillary A. 1st part – gives rise to superior or highest thoracic A. [shoulder] 2nd part – gives rise to thoracoacromial and lateral thoracic A. 3rd part – gives rise to subscapular [largest branch], anterior and posterior humeral circumflex Brachial A. [arm] Branches: profunda brachii, superior and inferior ulnar collateral arteries, muscular, nutrient A. to humerus Radial A. [forearm] Branches: radial recurrent A., muscular and superficial palmar branch, 1 st dorsal metacarpal branch, arteria princes pollicis, arteria radialis indicis Ulnar A. [forearm] Branches: anterior and posterior ulnar recurrent, the common, anterior and posterior interosseous, deep palmar arch [palmar, metacarpal, perforating br.] Scapular anast. Joins axillary system w/ subclavian system Elbow joint ansas. Joins branches of brachial A. w/ radial & ulnar A.

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Wrist & arm anast.

Joins branches of radial & ulnar A.

Lymphatic drainage of upper limb Name of nodes Features Axillary LN Drains from entire upper limb , located as follows: anterior pectoral, posterior subscapular, lateral, infraclavicular/deltopectoral and apical LN Supratrochlear LN Aka cubital LN which drains from medial fingers, medial arm and forearm Clinical notes Volkmann’s ischemic contracture

 Caused by supracondylar fracture of humerus w/c compress brachial A. resulting in ischemia of forearm &hand. The hand is flexed at wrist & fingers are flexed at the interphalangeal joints. Dupuytren’s contracture

 Caused by fibrosis and shortening of palmar aponeurosis. Thickening and shortening of the bands of aponeurosis over the flexor tendons results in flexion of ring and little fingers. Brachial plexus [from ventral rami of spinal nerves C5-T1] Branch Name Distribution Lateral cord Lateral pectoral [C5-7] Pectoralis major and minor muscles Medial cord Medial pectoral [C8, T1] Pectoralis major and minor muscles Medial brachial cutaneous [C8-T1] Skin on medial aspect of arm Medial antebranchial cutaneous Skin of forearm Posterior Upper subscapular [C5-6] Subscapularis, upper part Thoracodorsal [C6-8] Latissimus dorsi Lower subscapular [C5-6] Subscapularis, lower part Terminal branches of brachial plexus Name Features Musculocutaneous [C5-7] Supplies coracobrachialis, brachialis, biceps brachii Axillary [C5-6] Supplies deltoid, teres minor and major muscles Radial [C5-8, T1] Largest branch of brachial plexus and is the sole innervation of extensor compartments of arm and forearm, supplies most of the cutaneous innervations to back opf arm, forearm and hand Ulnar [C8, T1] Main nerve to small muscles of the hand Median [C5-8, T1] Supplies all muscles in anterior forearm [except flexor carpi ulnaris and ulnar half of flexor digitorum longus – ulnar N., brachioradialis – Branch: radial N.], also supplies thenar muscles and lateral 2 Anterior interosseous nerve lumbricals Supplies flexor pollicis longus, lateral half of flexor digitorum profundus and pronator quadratus

Origin Lateral Posterior Posterior

Medial

Muscles of pectoral girdle and shoulder Muscles that move shoulder girdle Name Innervation Trapezius Accessory N. [motor], C3-4 [sensory] Latissimus dorsi Thoracodorsal N. Rhomboid major and minor Dorsal scapular N. Levator scapulae Dorsal scapular N. [motor], C3-4 [sensory] Serratus anterior Long thoracic N. Pectoralis minor Medial pectoral N. Subclavius Nerve to subclavius [upper trunk of brachial] Rotator [musculotendinous] cuff muscles – major stabilizing factor for shoulder joint Name [from top – SITS] Innervation Supraspinatus Suprascapular N. infraspinatus Suprascapular N. Teres minor Axillary N. Subscapularis Upper and lower subscapular N. Other muscles that move the humerus Name Innervation Pectoralis major Lateral pectoral N. Deltoid Axillary N. Latissimus dorsi Thoracodorsal N. Teres major Lower subscapular N. Clinical notes Inflammation of Rotator cuff  Tendon of supraspinatus is most commonly affected.  Pxs w/ rotator cuff tears experience pain anterior to glenohumeral joint during abduction. Humeral dislocation

 Head of humerus is commonly displaced inferiorly then anteriorly and becomes positioned just inferior to coracoid process. This may stretch the axillary or radial nerve. Humeral fracture  In a fracture of the surgical neck of humerus, axillary neve may be lesioned, and posterior circumflex artery may be lacerated.  Fracture on the greater tubercle of humerus may result in avulsion of greater tubercle and detachment of the rotator cuff muscles from humerus.  A transverse fracture of humerus distal to deltoid tuberosity may result in abduction of proximal fragment by deltoid muscle.  In a midshaft spinal fracture of humerus, the radial nerve may be lesioned and the profunda brachii artery may be lacerated.  In supracondylar fracture of humerus, contraction of triceps and brachialis may shorten the arm. Median nerve may be lesioned as a result of an intercondylar or supracondylar fracture of the distal end of humerus.  In fracture of medial epicondyle of humerus, the ulnar nerve may be lesioned. Epicondylitis  LaTEral epicondyitis [TEnnis elbow] – infammation of common extensor tendon that results from forced extension and flexion of the forearm at the elbow. Pxs exhibit pain over the lateral epicondyle w/c may radiate down the posterior aspect of forearm.  Medial epicondylitis [golfer’s elbow] – inflammation of common flexor tendon that results from repetitive flexion and pronation of forearm at elbow. ARM AND FOREARM Cubital fossa [refer to Netter p. 402]  bounded by: brachioradialis [lateral], pronator teres [medial], brachialis and supinator [floor], skin, fascia and bicipital aponeurosis [roof]  Medial to lateral contents: median N., fats, brachial A. bifurcation, biceps tendon, radial and ulnar A, radial N.  crossed superficially by median cubital V. [for phlebotomy] Muscles of the Upper Arm [refer to Netter p. 403] Name Innervation Coracobrachialis Musculocutaneous N. Brachialis Musculocutaneous N. Biceps brachii Musculocutaneous N. Triceps brachii Radial N. Anconeus Radial N.

Actions Flex and adduct arm Flex elbow joint Flex elbow joint, supinates forearm Extends elbow joint Extends elbow joint

Muscles of flexor compartment of forearm [refer to Netter p. 402 & 416] Name Innervation Actions Superficial group Pronator teres Median nerve Pronates forearm Flexor carpi radialis Median Flex and adducts hand Palmaris longus Median Flex hand Flexor digitorum superficialis Median Flexes PIP Flexor carpi ulnaris Ulnar nerve Flex and adducts hand Deep group Pronator quadratus Median Pronates forearm Flexor pollicis longus Median Flex interphlangeal joint of thumb Flexor digitorum profundus Ulnar nerve Flexes DIP Muscles of extensor compartment of forearm [refer to Netter p. 403 & 414] Name Innervation Actions Superficial group Brachioradialis Radial Flex elbow Extensor carpi radialis longus Radial Extends and abducts hand Ext. carpi radialis brevis Radial Extends and abducts hand Extensor digitorum Radial Extends phalanges and wrist Extensor digiti minimi Radial Extends 5th finger Extensor carpi ulnaris Radial Extends and abducts hand Deep group Supinator Radial Supinates forearm Abductor pollicis longus Radial Abducts thumb Extensor pollicis brevis Radial Extend thumb Extensor pollicis longus Radial Extends thumb Extensor indicis Radial Extend index finger WRIST AND HAND Carpal tunnel  Formed poseriorly by 8 carpal bones.  Contents: median nerve, flexor digitorum superficialis & profondus, flexor pollicis longus.  Phalen’s test – dorsal surface of both hands pressed together w/ wrist flexion produces pain  Tinel’s test – tapping the median nerve produces pain

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Canal of Guyon  Located btw pisiform and hook of hamate superficial to carpal tunnel. The ulnar nerve, ulnar artery, and ulnar vein cross the wrist and pass into the hand after traversing the canal. Anatomic snuffbox [refer to Netter p. 434]  Lateral: tendons of abductor pollicis longus and extensor pollicis brevis  Medial: extensor pollicis longus  Floor: scaphoid and trapezium  Contents: radial artery  Its skin is innervated by superficial branch of radial nerve Thenar muscles Name Innervation Actions Abductor pollicis brevis Median N. Abducts thumb Flexor pollicis brevis Median N. Flex metacarpophalangeal jt. Thumb Opponens pollicis Median N. Opposes thumb to other digits Adductor pollicis Ulnar N. Adducts thumb Hypothenar muscles Name Abductor digiti minimi Flexor digiti minimi brevis Opponens digiti minimi Palmaris brevis

Innervation Ulnar N. Ulnar N. Ulnar N. Ulnar N.

Actions Abducts little finger Flexes metacarpophalangeal jt [LF] Opposes little finger to thumb, helps in cupping the palm Tenses skin on medial palm

Interosseus and lumbrical muscles Name Innervation Palmar interossei [3] Ulnar N. Dorsal interossei [4] Ulnar N. Lumbricals [4] Medial [1,2] - ulnar Lateral [3,4] – median NOTE: C6 dermatome – thumb, C8 – little finger Arteries of hand Name Radial A. Ulnar A. Dorsal carpal arch

Actions Adduct fingers, flex metacarpal jts Abduct fingers, flex metacarpal jts Flexes metacarpophalangeal jts., extend interphalangeal jts

Branches Dorsal digital A., princeps pollicis A., radialis indicis A. Deep palmar and superficial palmar arch 3 dorsal metacarpal A., dorsal digital A.

Thenar & midplamar spaces Thenar space Contents: 1st lumbrical, long flexor tendon [thumb and index finger] Midpalmar space Contents: lumbricals, long flexor tendons of medial 3 fingers Nerve injuries of upper extremities [refer to Netter p. 441] Injury Affected Causes Erb-duchenne C5-6 spinal n. Violent fall on shoulder [ex. palsy – upper [superior trunk] motorcycle], birth injury Klumpke’s C8-T1 spinal n. All from a height, birth injury paralysis - lower [inferior trunk] Thoracodorsal N. Latissimus dorsi Improper use of crutch, [+] difficulty in elevating trunk Long thoracic N. Serratus anterior Paralysis of serratus anterior, can’t abduct above the horizontal Musculocutaneous Biceps and nerve brachialis Axillary nerve Deltoids Fracture of surgical neck of humerus or inferior dislocation of shoulder jt. Radial nerve Extensors of Improper deltoid injection or wrist and fingers tight cast, Median nerve Thenar nuscles, Numb palm and finger, [recurrent lateral 2 fingers, inability to flex fingers, in branch] lumbricals typist, as in Dupuytren’s Ulnar nerve Medial 2 Inability to adduct/abduct lumbricals fingers, interosseous atropy Suprascapular N. Spinal accessory

Manifestations Waiter’s tip hand Clawhand or ape-hand deformity [cannot fist] Crutch palsy or Saturday night palsy Winged scapula Waiter’s tip hand Crutch pressure injury Wristdrop Papal benediction & forearm ‘ape-like hand’ Carpal tunnel syndrome Ulnar Clawhand Waiter’s tip position Drooping of shoulder

RAPID REVIEW  Muscles of the flexor forearm compartment NOT supplied by median nerve are the: flexor carpi ulnaris and ulnar half of flexor digitorum longus [w/c are supplied by ulnar nerve]  The only THENAR muscle NOT supplied by median nerve is the adductor polis [w/c is supplied by ulnar nerve]  Not strictly a thenar muscle – adductor pollicis muscle  All interosseus and lumbrical muscles are supplied by ulnar nerve EXCEPT the lateral 2 lumbricals [w/c are supplied by median nerve]

 musculocutaneous n. – main branch of the lateral cord  radial n. – biggest branch of brachial plexus  hearT-shaped vertebra = Thoracic  kidney-shaped vertebra = lumbar Brachioradialis  Function: “beer raising muscle”, flexes the elbow  Strongest when writ is oriented like holding a beer  Innervation: it’s a flexor muscle but innervated by radial nerve  The only flexor muscle supplied by radial nerve  [radial nerve usually supplies the extensors] CHAPTER 3 – LOWER EXTREMITY Bones of lower extremities Division Type Features Pelvic Pubis Forms the anterior and medial part of hipbone girdle Ilium Forms the lateral part of hipbone Ischium Posterior and inferior part of hipbone Acetabulum Formed by ilium, ischium and pubis Femur w/ fovea capitis [ligament of head], quadrate tubercle [quadratus femoris] Patella Largest bone to develop w/in tendon of a muscle , a sesamoid bone Tibia Weight-bearing bone of the leg, w/tibial tubrosity [patellar ligament] Fibula Non-weight bearing bone of the leg, w/ interosseous border Joints of the lower extremities Sacroiliac joint Synovial Hip joint Ball and socket Knee joint

Modified hinge jt

Ankle joint

Synovial hinge jt

Only joint btw pelvic girdle and axial skeleton Strengthened by 3 ligaments: iliofemoral [strongest], pubofemoral, and ischiofemoral lig. Located btw patella and femur, formed by lateral and medial condyles of femur and tibial plateus Include the talocrural, subtalar, and transverse tarsal joints

Ligaments of the lower extremity Name Features Iliofemoral Strongest and most important ligament of the hip joint Ischiofemoral Thinnest of the ligaments of hip joint Pubofemoral Resists excessive abduction of hip joint Patellar ligament Anterior ligament of knee joint Tibial collateral Important stabilizer of knee joint Fibular collateral Is taut and stabilizes the joint best when knee if fully extended Anterior cruciate Maximally taut and stabilizes the joint best w/ fully extended knee Posterior cruciate Maximally taut and stabilizes the joint best w/ fully extended knee Menisci of knee joint Shock absorbers, lateral meniscus is more movable Clinical notes Fracture of Femoral neck  The head of femur may undergo avascular necrosis as a result of disruption of the branches of medial circumflex femoral artery [main source of arterial supply to head & neck of femur]  In pxs w/ fractures of the femoral neck, the thigh is laterally rotated by the short lateral rotators of the thigh at the hip and the gluteus maximus. Dislocation of femoral head  This most commonly occur in posterior direction. The thigh is shortened and medially rotated by gluteus medius and minimus muscles.  The sciatic nerve may be compressed, resulting in weakness of muscles in the posterior thigh, leg, and foot, and paresthesia over the posterior and lateral parts of the leg and the dorsal and plantar surfaces. Knee injuries  The 3 most commonly injured structures at the knee are the tibial collateral ligament, medial meniscus and ACL [the terrible triad].  A blow to lateral apect of knee when foot is on the ground may sprain the tibial collateral ligaments; the medial meniscus may also be torn.  ACL tears may occur when tibial collateral ligament and medial meniscus are injured; a blow to the anterior aspect of the flexed knee may tear only ACL.  Pxs w/ a torn ACL exhibit an anterior drawer sign, in w/c tibia may be displaced anteriorly from the femur in the flexed knee. Ankle sprains  Inversion ankle joints are more common than eversion sprains at the talocrural joint. The anterior talofibular part of the lateral ligament is commonly torn in inversion ankle sprains. Veins of lower extremity Location Name of vein Superficial Dorsal venous arch Small saphenous Great saphenous Deep veins Venae comitantes

Distribution Drainage Dorsum of foot Small + great saphenous V. Posterior leg Popliteal vein Anterior leg Popiteal Paired, runs alongside of arteries

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Femoral vein Arteries of lower extremity Name Origin Femoral A. External iliac A. Popiteal A.

Femoral A.

Anterior tibial A Dorsalis pedis Posterior tibial

Popliteal A. Anterior tibial A. Popliteal A.

Internal iliac A.

Common iliac A.

Main venous structure draining the lower extremity Branches Superficial circumflex iliac, superficial epigastric, superficial and deep external pudendal, profunda femoris and descending genicular arteries Muscular br., articular br. to knee joint, terminal branches [anterior and posterior tibial arteries] Muscular and anastomotic branches Lateral tarsal, arcuate & 1st dorsal metatarsal A. Peroneal, nutrient A. to tibia, medial & lateral plantar, muscular branches & anastomotic branches Superior & inferior gluteal, and obturator artery

Clinical notes  Cruciate anastomosis in posterior thigh is formed by medial and lateral circumflex femoral A., inferior gluteal A. and 1st perforating A. This may contribute to collateral circulation of lower limb if femoral artery becomes occluded.  Anastomosis around knee joint is formed by descending genicular A. [from femoral A.], lateral femoral circumflex A. [from profunda femoris], articular branch [from popliteal A.], and branches from anterior and posterior tibial A.  Dorsalis pedis pulse may be evaluated by compressing the dorsal artery of foot against tarsal bones lateral to tendon of extensor hallucis longus. Nerves of lower extremity Name of nerve Features Lumbosacral Formed by ventral rami of L4 thru S3. The posterior and anterior division plexus form 2 terminal nerves: common peroneal/fibular N., and tibial N. Lumbosacral trunk Formed by fibers of L4 and L5 Terminal nerves of the lumbar plexus Name Component Features s Femoral N. L2-4 Largest branch of lumbar plexus, w/ cutaneous br. [gives rise to saphenous N., medial and intermediate cutaneous N. of thigh] , muscular br. & articular branches., susceptible to injury Saphenous Femoral N. Only branch of femoral N. to extend below the knee Obturator N. L2-4 Branches: anterior, posterior, and articular branches Clinical notes Femoral N. lesions  The femoral nerve may be damaged in the abdomen by an abscess of the psoas major. Pxs experience weakness in the ability to flex thigh at the hip, weakness in the abiity to extend the leg at the knee, and a diminished patellar tendon reflex. Saphenous N. lesions  Saphenous nerve may be lesioned during a surgical procedure of the leg to remove part of the great saphenous vein, or it may be lacerated as it pierces the wall of adductor canal. Pxs experience pain and paresthesia in the skin of the medial aspect of leg and foot. Obturator N. lesions  Obturator nerve is commonly lesioned in the pelvis. Pxs are unable to adduct the thigh at he hip and may have paresthesia in skin of the medial thigh. 5 collateral nerves of lumbar plexus Name of nerve Features Subcostal nerve Innervates abdominal musculature & skin of lateral & anterior abdominal wall iliohypogastric N. Innervates abdominal musculature and skin of inguinal and hypogastric regions of the lateral and anterior abdominal wall iIioiguinal N. Innervates the skin of the medial thigh, labium majus, and anterior scrotum Genitofemoral N. Innervates skin on medial thigh [femoral br.], & cremasteric M. [genital br.] Lateral femoral Inervates the skin of the lateral thigh cuaneous N. Clinical notes Lateral femoral cutaneous nerve lesions  The lateral femoral cutaneous nerve may be compressed as it passes posterior to lateral part of inguinal ligament just medial to anterosuperior iliac spine. Pxs w/ compression of the lateral femoral cutaneous nerve [meralgia paresthetica] present w/ pain and paresthesia in the anterolateral thigh. Terminal branches of lumbosacral plexus Name of nerve Features Sciatic nerve Largest branch of lumbosacral plexus, largest nerve of the body, branches: tibial and common peroneal N. Superior gluteal N Innervates gluteus medius and minimus, tensor fasciae latae Inferior guteal N. Innervates gluteus maximus muscle

Tibial N.

Common fibular / peroneal nerve Superficial fibular Deep fibular N.

Principal nerve to posterior thigh and leg, sole of foot, divides into medial plantar N. [w/c innervates flexor digitorum brevis, flexor hallucis brevis, abductor hallucis and 1st lumbrical] and lateral plantar N. [w/c innervates skin of lateral side of the sole of foot and lateral ½ digits. Innervates the short head of biceps femoris, divides into superficial and deep fibular N. as it enters he fibularis longus muscle. Innervates the fibularis longus and brevis muscles Innervates tibialis anterior, extensor hallucis longus, extensor digitorum longus, and peroneus tertius muscle

Clinical notes Superficial gluteal N. lesions  This pxs have weakness in the ability to abduct the thigh at the hip. They experience a “waddling or trendelenburg gait”, in w/c the pelvis sags on side of the unsupported limb. Inferior gluteal N. lesions  This pxs have a weakness in the ability to laterally rotate and extend the thigh at the hip.  They have difficulty extending the thigh at the hip from a flexed position as in climbing the stairs or rising from a chair.  Pxs may have a gluteus maximus gait in w/c they thrust their torso posteriorly in an attempt to counteract the weakness of the gluteus maximus. Sciatic N. lesions  Susceptible to damage from an IM injection in the lower medial quadrant of gluteus maximus muscle, or it may be compressed as a result of posterior dislocation of the femur.  “Foot drop” – all muscles of the knee are paralyzed due to sciatic nerve lesion. Common fibular N. lesions  It is the most frequently lesioned nerve in lower limb. This usually occurs as it passes around neck of fibula.  Pxs experience “foodrop” w/c results from a loss of dorsifexion at the ankle and loss of eversion. They also have pain and paresthesia in the lateral leg and dorsum of the foot.  Pxs w/ foodrop may have “steppage gait” in w/c they raise their affected leg high off the ground and their foot slaps the ground when walking.  In piriformis syndrome, the common fibular nerve may be compressed by fibers of the piriformis muscle when the nerve passes thru the piriformis rather than anterior to it w/ tibial N. Superficial fibular N. lesions  The nerve may be lesioned as he nnerve emerges from lateral compartment of the leg. Pxs experience pain and paresthesia in the dorsal aspect of the foot. Deep fibular N. lesions  The nerve may be compressed in the anterior compartment of the leg. This pxs may have footdrop and parethesia in skin of the webbed space btw the great toe and 2nd toe. Lymphatics of lower extremity Name Superficial inguinal nodes Deep inguinal nodes Popliteal LN

Distribution Receive lymph from thigh, foot, leg, buttock, perineum Receive lymph from deep structure of thigh and leg Receive lymph from deep structures of leg below the knee

GLUTEAL REGION Important features of gluteal region Sacrotuberous lig. Connects posterior iliac spines, sacrum, coccyx to ischial tuberosity Sacrospinous lig. Connects posterior surface of sacrum and coccyx w/ ischial spine Greater sciatic Transmits: piriformis M., sciatic N., superior and inferior gluteal N. and foramen vessels, pudendal N., internal pudendal A and V, posterior femoral cutaneous N, nerve to quadratus femoris and obturator internus Lesser sciatic Transmits: tendon of obturator internus, nerve to obturator internus, foramen pudendal nerve, internal pudendal artery and vein Muscles of gluteal region [refer to Netter p. 461] Name Innervation Gluteus maximus Inferior gluteal N. Gluteus medius Superior gluteal N Gluteus minimus Superior gluteal N Tensor fasciae latae Superior gluteal N Piriformis S1-2 lumbar plexus Obturator internus N. to obturator internus Superior gemelli N. to obturator internus Inferior gemelli N. to quadratus femoris Quadratus femoris N. to quadratus fwmoris

Actions Extends, laterally rotates thigh Abducts and medially rotates thigh Abducts and medially rotates thigh Flex, abducts,medially rotates thigh Laterally rotates thigh Laterally rotates thigh Laterally rotates thigh Laterally rotates thigh Laterally rotates thigh

Vessels of gluteal region Name Features Superior gluteal A. Largest branch of internal iliac A., w/ superior and inferior branches Inferior gluteal A. Gives rise to companion artery to sciatic nerve Internal pudendal A. Distributed to perineum, no branches to gluteal region Gluteal Veins Provide alternative pathway for return of blood to lower extremities

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THIGH Important features of thigh Fascia lata Deep investing fascia of lata, acts like a tight stocking Iliotibial tract Important in maintaining posture and in locomotion Saphenous opening Aka fossa ovalis, transmits great saphenous V. & superficial femoral A Femoral sheath Derived from transversalis fascia. Lateral-medial: invests the femoral A, femoral V, and femoral canal Femoral canal Most medial compartment of femoral sheath, a potential weak area Femoral ring Lacunar ligament [medial], femoral V [lateral], inguinal ligament [anterior], superior ramus of pubis and pectineal ligament [posterior] Femoral triangle Sartorius [lateral], Adductor longus [medial], iliopsoas and pectineus [floor] & Inguinal Ligament [base] - SAIL Contents: femoral N, A, V., inguinal LN, femoral sheath Adductor canal of Lies btw vastus medialis, adductor brevis and magnus, covered by Hunter or subartorial sartorius muscle [thus called subsartorial canal] canal Contents: femoral A + V, saphenous N., nerve. to vastus medialis, LN Cruciate anastomosis Provides an important potential collateral pathway to bypass an obstruction of external iliac or femoral artery Profunda femoris A Largest branch of femoral artery Perforating arteries Major supply to posterior thigh Muscles of posterior thigh [refer to Netter p. 461] Name Innervation Semitendinosus Tibial division of sciatic Semimembranosus Tibial division of sciatic Biceps femoris Long head: sciatic N. Short: common peroneal

Actions Extends thigh, flex knee, rotates leg medially Extends thigh, flex knee, rotates leg medially Extends thigh, flex knee, rotates leg laterally

Muscles of anterior thigh [refer to Netter p. 458] Name Innervation Actions Iliacus Femoral N. Flex thigh Psoas major Ventral rami [L2-3] Flex thigh Sartorius Femoral N. Flex and laterally rotates thigh, flex knee joint Rectus femoris Femoral N. Flex thigh, extend knee joint Vastus medialis Femoral N. Extends knee joint Vastus lateralis Femoral N. Extends knee joint Vastus Femoral N. Extends knee joint intermedius Articularis genus Femoral N. Retracts synovial membrane on extended knee Muscles of medial thigh [refer to Netter p. 459] Name Innervation Pectineus Femoral and obturator Obturator externus Obturator N. Gracilis Obturator N. Adductor longus Obturator N. Adductor brevis Obturator N. Adductor magnus Adductor part: obturator Hamstring: sciatic N. Vessels of thigh Name Femoral artery Obturator artery

Actions Flex and adducts thigh Laterally rotates thigh Adducts thigh, flex and medially rotates knee Adducts and laterally rotates thigh Adducts and laterally rotates thigh Adductor part: adducts and lat rotates thigh Hamstring: extends thigh

Branches Superficial epigastric, superficial circumflex iliac, superficial + deep external pudendal, profunda femoris [largest branch], medial + lateral femoral circumflex, perforating arteries, descending genicular arteries Anterior and posterior branches

LEG AND POPLITEAL REGION Muscles of the anterior and lateral compartments of the leg [refer to Netter p. 484] Name Innervation Actions Anterior group Tibialis anterior Deep peroneal Dorsiflex ankle, inverts foot Extensor digitorum longus Deep peroneal Extends toes, dorsiflex foot Extensor hallucis longus Deep peroneal Extends great toe, dorsiflex foot Peroneus tertius Deep peroneal Dorsiflex ankle and everts foot Deep group Peroneus longus Superficial peroneal Everts foot Peroneus brevis Superficial peroneal Everts foot Muscles of the posterior compartment of the leg [refer to Netter p. 482] Name Innervation Actions Superficial group Soleus Tibial N. Plantar flex foot Gastrocnemius [medial ,lateral] Tibial Plantar flex foot, flex ankle joint Plantaris Tibial Insignificant plantar flexor Deep group Unlocks knee in flexion and also

Popliteus Tibialis posterior Flexor hallucis longus Flexor digitorum longus

Tibial Tibial Tibial Tibial

Laterally rotates femur Plantar flex, inverts foot Flex big toe, plantar flex foot Flex toes, plantar flex foot

Popliteal fossa  Superiorly and medially: semimebranosus, semitendinosus  Superiorly and laterally: biceps femoris  Inferiorly and medially: medial head of gastrocnemius  Inferiorly and laterally: lateral head of gastrocnemius  Floor [anteriorly]: popliteal surface of distal femur  Roof [posteriorly]: deep popliteal fossa  Contents: [superficial to deep] tibial N., popliteal V, popliteal A., popliteal LN, small saphenous V., common peroneal and tibial N., posterior cutaneous N. of the thigh  Nerves found: sciatic [tibial+peroneal N] and posterior femoral cutaneous N. Nerves of the leg [refer to Netter p. 483-484] Name Origin Tibial N. Formed by L4-5, S1-3 Common peroneal Sciatic Deep peroneal Superficial peroneal

Common peroneal Common peroneal

Features Supplies all muscles of posterior leg compartment Branches: medial sural cutanous, medial calcaneal Branches: lateral sural cutaneous N., sural communicating N., recurrent articular branch Supplies all muscles of anterior leg compartment Supplies on lateral leg and foot

Arteries of leg and popliteal region [refer to Netter p. 483] Name Branches Popliteal A. Medial and lateral superior genicular A., medial and lateral inferior genicuar A., middle genicular A., sural arteries [largest branch] Genicular anastomosis Receives: popliteal A, femoral A, profunda femoris A. ant. + post. tibial A. Posterior tibial A. Nutrient A. to tibia, circumflex fibular A, medial posterior malleolar branch and medial calcaneal branches, peroneal A. Peroneal A. Muscular branches, nutrient A. to fibula, communicating banch to posterior tibial A., perforating branch, lateral posterior malleolar A. Anterior tibial A. Muscular branches, posterior and anterior tibial recurrent, A, medial and lateral anterior malleolar branches, dorsalis pedis FOOT Bones of foot 1. tarsal bones [7]  begin ossification before birth except for cuneiform and navicular, w/c begin at 3-4 years of age  Components: talus, calcaneus [largest tarsal bone, forms the heel of the foot, ossification at 6 mos.], navicular, cuboid, medial cuneiform [largest of the cuneiform bones], intermediate cuneiform, lateral cuneiform 2. metatarsal bones [5]  begin ossification at shaft in 2nd-3rd mos. in utero  2nd metatarsal [longest metatarsal]  5th metatarsal has prominent tubercle on its base 3. phalanges [14]  2 for the great toe and 3 for the remaining toes  Begin ossification at the shaft in 3rd month in utero Composition of foot Hindfoot Talus, calcaneus Midfoot Navicular, cuboid, cuneiform Forefoot Metatarsals and phalanges Intrinsic muscles on plantar surface [sole] of foot [refer to Netter p. 497-500] Name Innervation Actions st 1 layer Abductor hallucis Medial plantar N Abducts great toe Flexor digitorum brevis Medial plantar N Flex lateral 4 toes Abductor digiti minimi Lateral plantar N Abducts little toe 2nd layer Quadratus plantae Lateral plantar Flex toes when foot is plantar flexed Flexor digitorum Lateral plantar Flex lateral 4 toes accesorius Flexor digiorum longus Tibial N. Flex distal phalanges, plantar flex foot Flexor hallucis longus Tibial N. Flex distal phalanx of big toe, plantar flex foot st: Lumbricals [4] 1 medial plantar Flexes metatarsophalangeal and extend 2-4: lat. plantar interphalangeal joints rd 3 layer Flexor hallucis brevis Medial plantar Flexes matatarsophalangeal joint of great toe Adductor hallucis Lateral plantar Adducts great toe Flexor digiti minimi Lateral plantar Flexes metatarsophalangeal joint of little toe 4th layer

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Plantar interossei [3] Dorsal interossei [4]

Lateral plantar Lateral plantar

Adduct toes, flexes metatarsophalangeal jts Abduct toes, flexes metatarsophalangeal jts

Intrinsic muscles on dorsum of foot Name Innervation Extensor digitorum brevis Deep peroneal N. Extensor hallucis brevis Deep peroneal N.

Actions Extends toes Extends great toe

Posterior tibial pulse  Palpated btw posterior surface of medial malleolus & medial border of calcaneal tendon  Essential in occlusive peripheral arterial disease  Intermittent claudication characterized by leg cramps during walking and disappears after rest [due to ischemia] Arteries of foot [refer to Netter p. 495] Name Branches Medial plantar A Plantar digital A. to medial side of great toe, anastomotic branches Lateral plantar A Plantar metatarsal A, , anastomosis w/ deep plantar A. Dorsalis pedis A Medial and lateral tarsal A, 1st dorsal metatarsal A, arcuate A, deep plantar A Nerves of foot Name Deep peroneal N Medial plantar N

Origin Common peroneal Tibial N [terminal]

Lateral plantar N

Tibial N [terminal]

Saphenous N Fibular nerves Sural nerve

Femoral Common fibular Tibial+peroneal

Lymphatic drainage of foot Name Medial superficial lymph vessels Lateral superficial lymph vessels Deep lymph vessels

Distribution Extensor digitorm brevis, extensor hallucis brevis Abductor hallucis, flexor hallucis brevis, flexor digitorum brevis, 1st lumbrical muscles Flexor digiti minimi brevis, plantar and dorsal interossei, lateral 3 lumbricals, adductor hallucis Largest branch of femoral nerve, to foot [medial] Dorsum of foot, skin on sides of 1st and 2nd toes Accompanies small saphenous vein

Distribution Drains dorsum of foot and sole Drains lateral side of foot and sole Follow the main blood vessels, goes to popliteal LN

Nerve injuries of lower extremities [refer to Netter p. 502-506] Injury Affected Causes Manifestations Femoral nerve Quadriceps Cathetherization of Loss sensation over anterior femoris M. femoral artery thigh, medial leg and foot Obturator Obstetric procedures Decreased sensation over nerve and pelvic diseases upper medial thigh Sciatic nerve Misplaced Footdrop and lost of sensation intramuscular injection over the leg Common Extensors of Direct trauma to head Footdrop peroneal N. foot and toes of fibula, compression by leg cast Tibial nerve Puncture wound in [-] standing on tiptoes popliteal fossa Other Injuries of lower extremities Ischial bursitis Trochanteric bursitis Gluteus medius limp Piriformis syndrome Anterior tibilais strain/shin splints Deep fibular nerve entrapment/ski-boot synd. Gastrocnemius strain/tennis leg Calcaneal bursitis Calcaneal spur Medial plantar nerve compression Polagra Clubfoot/talipes Pes planus Claw toes Hammertoe Hallux valgus Tarsal tunnel syndrome Patellofemoral syndrome/runner’s knee Prepatellar bursitis/housemaids knee Subcutaneous infrapatellar bursitis or clergyman’s knee Deep infrapatellar bursitis

Weaver’s buttom Pain to iliotibial tract Gluteal gait Compression of sural N. by piriformis Edema and pain on distal 2/3 of tibia Compression by boots Tearing of medial belly of gastrocnemius Retroachilles bursitis Heel-spur syndrome Jogger’s foot Sever pain on metatarsal joint Foot twisted out of position Fallen arches Flexion of metatarsophalangeal joints and distal interphalangeal joint Permanent flexion of proximal phalanx at metatarsophalangeal joint Lateral dislocation of great toe Tibial nerve entrapment Direct blow to patella Friction between skin and patella Friction between skin and tibial tuberosity Friction between patellar ligament and tibia

Popliteal cyst/baker’s cyst Genu varum Genu vaLgum ACL injury – “anterior drawer sign” PCL injury – “posterior drawer sign”

Fluid-filled herniations of synovial membrane of knee joint Tibia diverted medially Tibia diverted Laterally Pushed tibialis posterior Lands on tibial tuberosity w/ flexed knee

RAPID REVIEW  Largest synovial joint of the body: knee joint  Tailor’s muscle and also the longest muscle of the body: sartorius  Most superficial muscle in the POSTERIOR leg compartment: gastrocnemius  Deepest muscle in POSTERIOR leg compartment: tibialis posterior  Strongest dorsiflexor and invertor of foot: tibialis anterior  Most lateral of the ANTERIOR leg compartment muscles: extensor digitorum longus  Most important stabilizer at knee joint: quadriceps femoris  Powerful push-off muscle during walking, running and jumping: flexor hallucis longus m.  Largest nutrient artery: Nutrient artery to tibia  Major blood supply to toes: dorsalis pedis A. or dorsal artery of foot  Do not act on knee joint: soleus M.  Triceps surae muscle: gastrocnemius [medial and lateral heads] and soleus muscles  Hamstring muscles: biceps femoris, semitendinosus & semimembranosus  Quadriceps femoris muscles: rectus femoris, vastus medialis, lateralis and intermedius  Most superficial of the 3 components of popliteal fossa: tibial N.  Only branch of lumbosacral plexus that contains both anterior [S2-3] and posterior [S1-2] division fibers: posterior femoral cutaneous nerve  Largest and longest branch of femoral nerve: saphenous nerve [the only branch of lumbar plexus to cross the knee joint]  Main stabilizer of femur: POSTERIOR cruciate ligament  Buttock quadrant safest for needle: Sciatic nerve [upper outer quadrant of buttock] Inversion vs. Invertion [2ND letter rule] Inversion of foot tIbialis anterior and posterior

Eversion of foot pErineus longus, brevis, terius

CHAPTER 4 – THORAX THORACIC WALL AND SKELETON [refer to Netter p. 470] Ribs 12 pairs, attached posteriorly to thoracic vertebrae True ribs [1st 7 ribs] Typical ribs [3-9] – w/ neck, head, tubercle and body False ribs [8-12 ribs] Atypical [1st, 2nd, 10th, 11th, 12th ribs] Sternum Until puberty, consists of 6 sternebrae Manubrium Widest and thickest of the 3 parts Body Articulates w/ manubriosternal joint Xiphoid Increases w/ age and may eventually fuse w/ the body Sternal angle of Lewis Aka as manubriosternal jt, marks the level of 2nd costal cartilage Clinical notes Rib fracture  Fractures of a rib commonly occur just ANTERIOR to the angle of the rib [weakest point] and may cause pneumothorax. Sternal angle of LOUIS – indicates the boundary of: 1. between superior and inferior mediastinum 2. beginning and ending of aortic arch 3. tracheal bifurcation 4. lower border of 4th thoracic vertebrae 5. convenient starting place for counting the ribs 6. the azygos vein drains into the superior vena cava Muscles of the thoracic wall Name Innervation Diaphragm Phrenic nerve External intercostals Intercostals N. Internal intecostals Intercostals N. Innermost intercostals Intercostals N. Subcostals Intercostals N. Transversus thoracis Intercostals N. Levator costarum C8-T1 spinal N Serratus posterior sup. Intercostals N. Serratus posterior inf. Intercostals N.

Actions Main muscle of inspiration, elevates the ribs Assists in inspire/expiration [down & forward] Assists in inspire/expiration [down & backward] Assists in inspiration & expiration [transversely] Assists in inspiration and expiration Assists in inspiration and expiration Elevates rib Assists inspiration by elevating ribs Assists expiration by depressing ribs

Clinical notes Phrenic N. lesions  An irritative lesion causes involuntary contractions of diaphragm and may result in hiccups.

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 A destructive lesion may result in paralysis and paradoxical movement of one half of diaphragm. The paralyzed dome of diaphragm fails to descend upon inspiration, and is forced superiorly by an increase in intraabdominal pressure Intercostal space  contains the intercostals muscles, and neurovascular bundle [VAN]  a needle to be placed into pleural cavity should be inserted midway between the ribs to avoid the neurovascular bundle and its collateral bundle Intercostal arteries  Anterior intercostal A. [anterior thoracic wall], from internal thoracic A. or musculophrenic A.  Posterior intercostal A. [posterior and lateral thoracic walls], from descending aorta. Intercostal veins  Anterior intercostal V. – drain anterior chest wall & empty into internal thoracic V. then to brachiocephalic veins  Posterior intercostal V. – drains posterior and lateral thoracic walls and empty into hemiazygos veins to the L and azygos veins to the R.  Azygos veins drains into SVC while hemiazygos vein drains into azygos vein. Intercostals nerves [refer to Netter p. 176]  from ventral rami of 1st 11 spinal nerves  lies between internal and innermost intercostals muscles  branches: collateral, lateral cutaneous, anterior cutaneous branches  the 7-11 intercostal nerves are aka as thoracoabdominal nerves BREAST or MAMMARY GLAND  w/ 15-20 lobes drained by a single lactiferous duct that opens to nipple  extend into axilla as axillary tail of SPENCE  supported by suspensory ligament of COOPER  nipple is at level of 4th ICS, its base extends from 2nd-6th ri  Supplied by: internal [from 2nd -4th ICS] and lateral thoracic [from 2nd -4th IC arteries], anterior intercostals, thoracoacromial A. [from axillary A. and perforating branch of internal thoracic and intercostals A.]  Drained by anterior axillary or pectoral nodes [75%] and parasternal nodes [20%], mediastinal nodes [clavicle], medial quadrants drain into internal thoracic nodes, & subareolar plexus of Sappey & circumareolar plexus as cutaneous drainage of thorax Clinical notes Adenocarcinoma of Breast  Most breast adenocarcinoma are lactiferous duct CA that begin as painless masses in the upper lateral quadrant [most common]  Late-stage adenoCA may cause retraction and fixation of the nipple and skin dimpling, w/c results from invasion of suspensory ligaments.  Adenocarcinomas metastasize mainly to axillary LN, but also to parasternal nodes to the opposite breast and to nodes of anterior abdominal wall.  In radical mastectomy, the breast is removed along w/ pectoralis major and minor muscles, axillary LN and vessels, and tributaries of axillary vein.  The long thoracic nerve or thoracodorsal nerve may be damaged in a mastectomy procedure w/c results in winged scapula, causing weakness in extension, adduction, and medial rotation of the humerus. MEDIASTINUM [refer to Netter p. 218-219]  space between paired pleural sacs, contains all thoracic organs [except the lung] Divisions Contents [from anterior to posterior] Superior mediastinum Thymic remnants, R and L brachiocephalic V, SVC [upper], L common carotid A., L subclavian A., aortic arch and branches, phrenic and vagus N, trachea, esophagus, thoracic duct, cardiac plexus of nerves, L recurrent laryngeal, prevertebral M., sympathetic trunks Inferior mediastinum Anterior division Thymic remnants and lymph nodes, sternopericardial ligaments Middle division Pericardium, heart, roots of great vessels, phrenic N, tracheal bifurcation and primary bronchi, arch of azygos vein, lymph nodes Posterior division Descending thoracic aorta, esophagus & esophageal plexus, vagus N., thoracic duct [cystera chili], azygos/hemiazygos V, lumbar & thoracic N., LN, sympathetic trunk & ganglia Clinical notes Thymoma  This may develop in superior and anterior mediastinum. Most pxs also have myashenia gravis. S/Sx includes an obstructed L brachiocephalic vein and chest pain. Superior Vena cava syndrome  SVC may be compressed by enlarged LN because of metastasis from bronchogenic CA  S/Sx: headache, edema of head and neck, prominent superficial veins and cyanosis. The veins of the upper limb fail to empty when the limb is elevated above the heart.  In complete SVC occlusion, venous return itself from head, neck and upper limbs is shunted into tributaries of the IVC.  Anastomoses of the SVC to IVC may occur btw lateral thoracic veins and superficial epigstric veins, and btw superior epigastric veins and inferior epigastric veins. Coactation of aorta

 A constriction of aorta that occur in proximal [INfantile type] or Distal [aDult type] to ligamentum arteriosum.  BP of these pxs is reduced in lower limb and elevated in head, neck and upper limbs.  Anasomoses in interostal spaces btw anterior intercosal A. [from internal thoracic A.], and posterior intercostals A. [from descending aorta] provide collateral circulation that bypasses the coarctation. Blod flows in the retrograde direction thru posterior intercostal A. into descending aorta.  Dilation of the anterior and posterior intercostals A. may result in resorption of ribs and “notching” observed on x-ray. Esophageal carcinoma  This commonly develops at 1 of the 3 sites of constriction in mediastinum. Aortic Arch aneurysm  This may compress trachea, esophagus, and L recurrent laryngeal N. Patients may experience difficulty in breathing, difficulty in swallowing and hoarseness. Cardiac tamponade  Results from fluid accumulation in pericardial cavity that compresses chambers of the heart.  Pericardial effusion may result in kausmaull respiration [distention of veins of neckon inspiration]  A penetrating wound of heart chamber or weakening of wall of the heart from MI may cause an acute tamponade as a result of accumulation of blood in pericardial cavity [hemopericardium].  Pxs w/ tamponade have decreased venous return and reduced cardiac output.  In pericardiocentesis to relieve tamponade, a needle is passed thru parietal pericardium to aspirate blood from pericardial sac [site: L xiphocostal angle]  The needle enters pericardial sac after passing thru skin, fascia, rectus sheath, rectus abdominis muscle, fibrous layer, and serous layer of parietal pericardium. Pericarditis  Causes stiffening & reduced compliancy of serous pericardium. The ventricles may not fill completely and cardiac output may be reduced because of pericardial effusion. PLEURA  Divisions and contents: Parietal pleura Costal pleura Diaphragmatic pleura Mediastinal pleura Cervical pleura Visceral pleura Endothoracic fascia Suprapleural membrane Pleural recesses

Highly sensitive to pain, temperature, touh and pressure Lines thoracic wall, supplied by intercostals N. Forms floor of pleural cavity, supplied by phrenic N. Forms lateral boundary of mediastinum, phrenic N. Aka as cupula of pleura Sensitive to stretching, suplied. by pulmonary plexus Binds parietal pleura to thoracic wall Reinforces cervical pleura Include costodiaphragmatic and costomediastinal recess

Clinical notes Pleuritis or pleurisy  The visceral or parietal pleura are inflamed and become rough, causing adhesions.  During respiration, friction created by adhesions may be audible as pleural rub.  Pxs w/ costal pleurisy may experience sharp pain localized over the adhesion site that increases w/ respiration.  Pxs w/ mediastinal or diaphragmatic pleurisy may have pain that is referred over C3 thru C5 dermatomes in supraclavicular region. Thoracentesis  A needle is used to sample or withdraw fluid from costodiaphagmatic recess, introduced into pleural cavity in the midaxillary line in 9th intercostals space after passing thru skin, superficial fascia, the 3 layers of intercostals muscles and parietal pleura.  To avoid intercostal nerves, the needle is inserted into the inferior part of the interspace. To anesthesize the intercosal nerves for relief of pain assoiated w/ rib fracture, the needle is inserted into superior part of interspace. Pneumothorax & Pleural effusion  In open pneumothorax, a penetrating wound of the chest wall pierces the costal pleura, or a penetrating wound in the root of the neck pierces the cervical pleura. Pleuritic pain results from stimulation of the intercostals nerves. o Air enters the affected pleural cavity during inspiration, but the negative intrapleural pressure is lost and the lung on the affected side collapses. The heart and the other mediastinal structures shift AWAY from the affected side and compress the opposite lung. o During expiration, air is expelled from the affected pleural cavity thru the wound, and the heart and other mediastinal structures shift back to affected side. Shifting of mediastinal structures reduces venous return to the heart.  In tension pneumothorax, a penetrating wound of parietal pleura creates a valve-like effect in pleura during respiration. o Air enters the pleural cavity during inspiration and the lung on affected side collapses, the heart and other mediastinal structures shift AWAY from affected side & compress the opposite lung. o During expiration, a flap of pleural tissue that closes the wound prevents expulsion of air. w/ each breath, intrapleural pressure is increased and the shift of heart and mediastinal structures to the opposite side is augmented. Cardiac output, venous return, and respiratory function are compromised. o A pleural effusion is an accumulation of fuid in pleural cavity and may be caused by obstruction of veins or lymphatic vessels that drain the thorax or by an inflammation of structures near the pleura.

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

In a hemothorax, blood accumulates in pleural cavity from hemorrhage of anterior or posterior intercostals vessels or internal thoracic vessels.  In chylothorax, lymph accumulates in a pleural cavity as a complication of mediastinal surgery or trauma that injures the thoracic duct. TRACHEA, BRONCHI AND LUNGS [refer to Netter p. 186-190] Trachea Begins at lower border of cricoid [C6 vertebra], w/ 16-20 hyaline cartilage 10-12 cm long, 2.5 cm diameter in male, slightly smaller in females Ends at level of sternal angle to divide into the 2 main bronchi Bronchi R main bronchus Shorter, wider, more vertical than L main bronchus, gives rise to R upper lobe bronchus [epiarterial bronchus], crossed by azygos veins More likely to contain inhaled objects because it is closer to trachea L main bronchus Longer, narrower, more horizontal than R main bronchus Epiarterial bronchi Is the most superior of the lobar bronchi, aka hyparterial bronchus Lungs W/ a main bronchus, 1 pulmonary A., and 2 pulmonary V. R lung Shorter than left because of dome of diaphragm, divided into upper, middle and lower lobes by oblique and horizontal fissures It has 3 lobar and 10 segmental bronchi L lung Divided into upper and lower lobes by the oblique fissure, w/ cardiac notch where heart and pericardium lies, lowest part is called lingula It has 2 lobar and 8 segmental bronchi Clinical notes Breath sounds  Breath sounds from superior lobe of each lung may be auscultated on the anterior and superior aspects of thoracic wall.  Breath sounds from inferior lobe of each lung may be auscultated on posterior and inferior aspects of the back.  Breath sounds ffom middle lobe of R lung, may be auscultated on anterior chest wall ner the sternum, inferior to R 4th costal cartilage. Foreign body aspiration  An aspirated foreign body is more likely to enter the R main bronchus because it is shorter, wider and more vertical than the L main bronchus.  In a px who is standing or sitting, the foreign body tends to become lodged in the posterobasal segment of the inferior lobe of the R lung. Emphysema  The respiratory tissue is destroyed resulting in permanent abnormal enlargement and increased radiolucency of the affected air spaces, and formation of blebs or bullae.  In spontaneous pneumothorax, an emphysematous bleb spontaneously ruptures, air is introduced into pleural cavity thru the visceral pleura, and conditions similar to an open or a tension pneumothorax result.  MC site of a spontaneous pneumothorax: visceral pleura of superior lung lobe Surfaces of the lungs Diaphragmatic surface Costal surface Mediastinal surface

Inferiorly to fit the diaphragm Convex to fit against thoracic wall Concave to fit against pericardium

Bronchopulmonary segments of the lung [refer to Netter p. 188-189]  part of lung lobe supplied by segmental [tertiary] bronchus and its accompanying branch of pulmonary artery Segments R lung L lung Upper lobe Apica, posterior, anterior [3] Apicoposterior, anterior, superior & inferior lingular [4] Middle lobe Medial & lateral [2] None [corresponds to lingular] Lower lobe Superior, basal medial, anterior Superior, basal anteromedial, lateral & posterior [5] lateral & posterior [4] Total lobes 10 8 Clinical notes Bronchogenic CA  May metastasize thru lymph channels but may also penetrate the wall of a tributary of a pulmonary vein and metastasize thru pulmonary and systemic circulations.  Supraclavicular LN may act as sentinel nodes indicating presence of a malignancy.  Enlarged supraclavicular LN on R may indicate malignancy in thorax.  Enlarged supraclavicular LN on L may indicate a malignancy in thorax, abdomen, or pelvis because all lymph below diaphragm is returned to venous system on L by way of thoracic duct.  A pancoast tumor that develops in apical part of superior lobe of either lung and may cause thoracic outlet syndrome.  Thoracic outlet syndrome results from compression of sympathetic trunk, subclavian vessels, recurrent laryngeal nerve or inferior trunk of brachial plexus in root of the neck. This pxs may have: Horner’s syndrome [anhydrosis, loss of sweating, ptosis, drooping of upper eyelid, and miosis].  Decreased radial pulse in upper limb caused by compression of subclavian artery and vein.  Hoarseness and dysphagia resuling from compression of a recurrent laryngeal nerve.

 Paresthesia in forearm and hand, and weakness and atrophy of hand musles as a result of compression of C8 and T1 ventral rami in the inferior trunk of brachial plexus. Blood vessels of the lungs Pulmonary A. Carry deoxygenated blood to alveolar capillary plexuses, w/ L and R branches Pulmonary V. Carry oxygenated fom lungs to L atrium, 5 in number Bronchial A. Supply oxygenated blood to bronchial tree and visceral pleura L side – 2 bronchial A. arising from descending thoracic aorta R side - bronchial A. arising from 3rd R posterior intercostals A. Bronchial V. Drain deoxygenated blood from bronchial tree and visceral pleura [2 per side R side – empty into azygos vein, L side – empty into hemiazygos vein Lymphatic drainage of lungs Superficial lymphatic plexus Deep lymphatic plexus Peribronchial pulmonary nodes Bronchopulmonary nodes Tracheobronchial nodes

Drains beyond hilus Follows along bronchial tree to the hilus Course along w/ deep plexus Located at root of the lung Empties into R and L subclavian veins

Nerve supply of the lungs [refer to Netter p. 195] Name Origin Parasympathetic fibers Vagus N. Sympathetic fibers Upper 5 symph. ganglia Visceral afferent fibers Vagus N.

Features Bronchial constriction + mucus secretions Produce bronchial relaxation Sensitive to stretch and participate in reflex control of respiration, also for cough reflex

Muscles involved in respiration Muscles of respiration External, internal and innermost intercostals muscles, subcostal muscles and transverses thoracis muscles Accessory muscles of Sternocleidomastoid, scalenus anterior and medius, serratus anterior, respiration pectoralis major and minor Respiratory Most important muscle of respiration [quiet respiration] diaphragm Receives motor [phrenic N], sensory [phrenic and intercostals nerves] Muscular diaphragm w/ sternal part, costal part, and lumbar part Ligaments of the lungs Medial arcuate lig. Lateral arcuate lig. R crus L crus

Fascial thickening over upper part of psoas major muscle Fascial thickening over upper part of quadratus lumborum M. Longer and larger than left, from upper 3 lumbar ertebrae From bodies of upper 2 lumbar vertebrae

Openings in the diaphragm Esophageal T10 hiatus Aortic hiatus T12 Vena caval hiatus T8

Transmits esophagus, vagus N, esophageal branches of L gastric vessels, lymphatics from lower 3 rd of esophagus Transmits aorta, thoracic duct, sometimes azygos veins Transmits inferior vena cava and branches of R phrenic N.

Clinical notes Diaphragmatic hernia  Occur at 1 of 4 locations: 1. Congenital diaphragmatic hernia may occur in the L posterolateral part of diaphragm just anterior to quadratus lumborum. 2. Hiatal hernia may occur at esophageal hiatus. In a sliding hiatal hernia [MC type], the abdominal part of esophagus and part of stomach herniated thru esophageal hiatus into mediastinum. Gastroesophageal reflux or heartburn may result from sliding hiatal hernia. 3. Paraesophageal hernia may also occur at esophageal hiatus where fundus or body of stomach herniates into the mediastinum adjacent to esophagus. 4. Retrosternal diaphragmatic hernia may occur in the anterior part of diaphragm adjacent to xiphisernal joint PERICARDIUM Fibrous Serous Pericardial sinus

Tough fibrous sac surrounding the heart Covers heart [visceral], and inner surface of fibrous pericardium [parietal] w/ oblique and transverse pericardial sinus

HEART  Layers: epicardium [outer], myocardium and endocardium [inner]  Skeleton of heart is consists of annuli fibrosi Surfaces of the heart [refer to Netter p. 202] Diaphragmatic surface Formed by L ventricle and narrowed part of R ventricle Sternocostal surface Composed of R atrium and R ventricle Obtuse margin Formed entirely by L ventricle Acuate margin Formed largely by R ventricle Right margin Formed by superior vena cava and right atrium Left margin Formed by left ventricle and L atrium Chambers and valves

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R atrium

L atrium R ventricle L ventricle Pulmonary valve Aoric valve tRicuspid valve MitraL valve

Receives blood from SVC & IVC, coronary sinus, anterior cardiac V., larger and thinner walled than L atrium, w/ pectinate muscles w/ valve of coronary sinus [thebesian], and valve of IVC [Eustachian] the fossa ovalis marks the site of foramen ovale in embryonic heart thru w/c blood passes from R and L atrium before birth Receives blood from 4 pulmonary veins, left interatrial septum [anterior wall] w/ papillary M., chordae tendinae, moderator band/septomarginal trabecula w/ trabeculae carnae, no moderator band, 2 papillary M. [ant erior, posterior] w/ 3 semilunar cusps, has associated pulmonary sinuses w/ 3 semilunar cusps and sinuses named according to their fetal position Guards the R atrioventricular orifice, w/ anterior, posterior and septal cusps Guards the L atrioventricular orifice

Heart sounds [refer to Netter p. 210] 1st sound [lub] Closure of atrioventricular orifice [MV & TV] at start of systole 2nd sound [dub] Closure of AV & PV at end of systole Tricuspid valve At lower end of sternum opposite 4-6th ICS Mitral valve At apex in L 5th ICS Pulmonary valve At medial end of L 2nd ICS Aortic valve At medial end of R 2nd ICS Clinical notes Valvular stenosis  Diseases such as rheumatic fever may cause stenosis of aortic or mitral valve  Mitral valve stenosis impedes flow of blood from LA to LV.  Aortic valve stenosis slows the rate at w/c blood empties from LV. A defect in leaflet or a cusp of any of the 4 valves may result in a prolapse of that valve component and regurgitation of blood back into chamber behind the valve. Prolapse is commonly seen in leaflets of mitral valve. Heart murmur  Sound that result from vibrations produced by turbulent blood flow [from stenotic or incompetent valve, from increased flow thru a valve, or from a dilated heart chamber adjacent to valve]  Can occur during diastole [mitral valve stenosis], systole [aortic valve stenosis] and may have a longer duration than normal heart valve sounds. Conducting system of the heart [refer to Netter p. 213] Sinoatrial node Pacemaker of the heart, initiates stimulus that causes contraction Atrioventricular Receives impulse generated in sinoatrial node AV bundle of HIS Begins from AV node and ends as plexus of subendocardial Purkinje fibers Blood supply of the heart [refer to Netter p. 204] Name Origin Distribution R coronary A. R aortic R ventricle, posterior half of interventricular septum sinus Branches: A. to sinoatrial node and atrioventricular node, R marginal A, posterior interventricular A. L coronary A. L aortic sinus L atrium, L ventricle, anterior half of IV septum Branches: anterior interventricular A., circumflex A., L marginal A. diagonal A., posterior ventricular A. Venous drainage of the heart Cardiac veins Largest of which is the coronary sinus btw tricuspid valve & valve of IVC Great cardiac V. Drains into L end of coronary sinus, courses w/ anterior interventricular A. Middle cardiac V Empty along midpoint fo coronary sinus,alongside posterior interventricular A Small cardiac V. Accompanies R marginal A., aka as venae cordis minimae Clinical notes Angina pectoris  Refers to chest pain that resuls from transient ischemia brought by exertion.  This ischemia results from reduced blood flow to cardiac muscle because of narrowing of a coronary artery, but there is no loss of cardiac muscle cells. Pxs have substernal pain referred over T1-5 dermatomes of thoracic wall corresponding to same segments of spinal cord that provide sympathetic innervation to the heart.  Referred pain may be felt in T1 dermatome in the medial aspect of L arm and forearm and may be felt over cervical dermatomes in neck, up to level of angle of mandible. Myocardial infarction  Results from localized avascular necrosis of cardiac muscle cells caused by ischemia.  The anterior interventricular artery is a common site of an occlusion that results in an acute MI. less frequently occluded are the R coronary A. and circumflex branch of L coronary artery.  In pxs, the onset of an MI is usually marked by sudden, severe pain beneath the sternum. Nerve supply of the heart Name Sympathetic fibers Parasympathetic fibers Visceral symph. fibers Visceral parasymp.

Origin ANS ANS Thoracic spinal N. Inf.vagal ganglion

Features ↑heart rate, ↑ contraction, dilatation of arteries ↓ heart rate, ↓ ventricular contraction Cardiac reflexes, sole pain conductors [heart] Sensory input for cardiac reflexes

Fetal circulation  Oxygenated blood from placenta enters fetus thru umbilical V. and passes to liver → shunted to IVC via ductus venosus → RA → foramen ovale → LA → RV → pulmonary trunk [deoxygenated] → bypass lung → ductus arteriosus → aortic arch  Deoxygenated blood then returns to placenta via umbilical arteries Changes after birth  Contraction of umbilical A. stops flow of blood to placenta, its remnant then forms the medial umbilical ligament  The umbilical V. closes and obliterates to form ligamentum teres hepatis  The ductus venosus closes and obliterates to form ligamentum venosum establishing normal circulation to the liver  w/ expansion of the lungs and rise in the left atrial pressure, foramen ovale closes and its flaplike valve eventually fuses w/ interatrial septum giving rise to fossa ovalis  ductus arteriosus closes and obliterates to form ligamentum arteriosum Clinical notes Atrial septal defect  A small patency in upper part of fossa ovalis of interatrial septum may be present but is not symptomatic a large patency in fossa ovalis may form a symptomatic ASD.  Normally, BP is higher in L side of heart than in R side of heart in postnatal life.  In this pxs, blood from L atrium will be shunted thru defect into R atrium. Ventricular septal defect  A large postnatal defect in interventricular sepum [often membranous part], results in too much pulmonary blood flow caused by a shunt of blood from L ventricle into R ventricle. In pxs w/ VSD, pulmonary HPN may result causing CHF. AV block  In an atrioventricular heart block, conduction is slowed thru AV node, some impulses are not transmitted thru the node, or in a complete block, no impulses are conducted thru AV node.  In a complete AV block, the cotractions of atria and ventricles become dissociated, and these chambers beat independently.  The atria may continue to contract about 70 times/min; a pacemaker may develop in AV bundle distal to the site of the block, initiating contraction of the ventricles at a rate of 30-40 times/min. ESOPHAGUS [refer to Netter p. 220]  Passes thru diaphragm at level of T10 Constrictions on barium swallow: Relationships: 1. begins at level of 6th cervical vertebra Anterior: trachea to its bifurcation 2. where it is crossed by L main bronchus Posterior: upper 4 thoracic vertebrae 3. where it lies behind L atrium where L To the left: aortic arch, thoracic duct, L atrium is enlarged recurrent laryngeal nerve 4. where it passes thru diaphragm To the right: mediatinal pleura Clinical notes Esophageal disorders  GERD/heartburn may result from incompetent LES. Pxs complain of substernal burning that is worst w/ lying down.  In Achalasia, the smooth muscle sphincter of esophagus fails to relax. Pxs have difficullty swallowing liquids and solids.  Hirschprung’s disease is caused by absence of terminal sympathetic ganglia.  Epinephric diverticulum may develop just superior to LES. These diverticula are false or pulsion diverticula not consist of all of the layers of esophagus. MC it occurs in sgmoid colon. Blood vessels & lymphatics of esophagus Location Venous supply Arterial supply Upper 3rd Inferior thyroid V. Inferior thyroid A. rd Middle 3 Azygos veins Esophageal br. of descending thoracic aorta rd Lower 3 L gastric vein L gastric & inferior phrenic A. Nerve supply of esophagus Sympathetic fibers Parasympathetic fibers Vagal visceral afferent

Lymphatics Deep cervical LN Superior & posterior mediastinal LN L gartic nodes & celiac LN

Producing vasoConstriction when stimulated Affects peristalsis and act on enteric nervous system Concerned w/ reflex activity of esophagus

THYMUS  Lymphoid organ lying behind the sternum in superior mediastinum  Important source of T lymphocytes & crucial to establishment of immune competence after birth  Begins involution after puberty  Supplied by branches of internal thoracic and inferior thyroid arteries  Drains largely to L brachiocephalic vein Arteries of the thorax Name Ascending aorta Aortic arch

Branches R and L coronary arteries 3 brachiocephalic, L common carotid, L subclavian, thyroidea ima

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Descending [T4] thoracic aorta Supreme intercostals Internal thoracic Pulmonary trunk

Posterior intercostals A., subcostal A., bronchial A., esophageal A., superior phrenic A., pericardial A., mediastinal A. From costocervical trunk and supplies the 1 st 2 ICS Anterior intercostals, musculophrenic, superior epigastric, pericardiophrenic, perforating branches to the intercostals spaces R and L pulmonary arteries

Great systemic veins of the thorax [refer to Netter p. 195] Name Features R brachiocephlic V. Receives R internal thoracic V. [its only thoracic tributary] L brachiocephlic V. Receives L internal thoracic v, L superior intercostals V, inf. thyroid V. Superior vena cava Receives the azygos veins Inferior vena cava Passes at level of 8th thoracic vertebrae Azygos V. Drains R posterior intercostals V. except the first, important tributaries include bronchial, esophageal, hemiazygos, accessory hemiazygos V. Hemiazygos V. Receives lower 4 L posterior intercostals veins Access. hemiazygos Drains the 4th-7th or 8th intercostals spaces Other nerves of the thorax Name Origin Phrenic N. Ventral rami [C3, 4, 5] its major contribution - C4 Vagus N. Brainstem

Features Sole motor innervation to respiratory diaphragm, pain from areas supplied by phrenic N. is usually referred to base of neck and tip of shoulder Supplies parasympathetic and general visceral afferent innervation to thoracic viscera, important branches: cardiac, pulmonary, esophageal, L+R recurrent laryngeal N

Nerve supply of thorax Autonomic plexus of thorax Sympathetic and parasymphathetic fibers General visceral afferent fibers Visceral nerves Superficial cardiac plexus Deep cardiac plexus Coronary plexuses Pulmonary plexus Esophageal plexus Thoracic sympathetic trunk Thoracic sympathetic nerves Lymphatic drainage of thorax Name Parasternal nodes Posterior intercostals nodes Diaphragmatic nodes Posterior mediastinal nodes Brachiocephalic nodes Tracheobronchial nodes Bronchomediastinal trunk Thoracic duct Right lymphatic duct

Function below level of consciousness Sensory limb of autonomic reflex arc Control function of the heart Lies below the level of aortic arch Btw aortic arch and tracheal bifurcation Extensions of cardiac plexus along coronary A. Nerve supply to lungs Formed by stand of vagus N. W/ 11-12 segmentally arranged ganglia Include gray and white ramus communicans

Drainage From thoracic wall, upper anterior abdominal wall, diaphragm From thoracic wall and paravertebral region From diaphragm, pericardium, and upper liver surface From pericardium and esophagus From heart, pericardium, thymus, and thyroid Receive lymphatic drainage from bronchopulmonary nodes Post medistinal, brachiocephalic, tracheobronchial parasternal L side of head and neck [L internal jugular lymph trunk], L upper extremity [L subclavian lymph trunk], L side of thoracic cavity [L bronchomediastinal lymph trunk] R side of the head, neck, thorax, R upper limb

RAPID REVIEW Batson’s plexus  Communication w/ vertebral veins  Route for hematogenous spread to vertebral column and hips Serratus anterior innervation and action  C5-6-7 raise your wings up to heaven  Inability to raise arm past 90 degrees  Winging of the scapula  Long thoracic nerve innervates serratus anterior CHAPTER 5 – ABDOMEN ANTERIOR ABDOMINAL WALL Fasciae of the abdominal wall Superficial layer of superficial fascia/Camper’s fascia Deep layer of superficial fascia/ Scarpa’s fascia Deep fascia Transversalis fascia

Fatty layer Membranous layer, most apparent on the abdominal wall, it continues as superficial perineal fascia/Colle’s fascia [perineum], Dartos fascia [scrotum] and superficial penile fascia Thin layer covering external surface of abdominal M. Gives rise to internal spermatic fascia [testis and spinal cord]

Muscles of the anterior abdominal wall [refer to Netter p. 232-234] Name Innervation Actions External abdominal Iliohypogastric, and Flexes and rotates trunk, depreses ribs in forced oblique ilioinguinal N. expiration [fibers runs medially and inferiorly] Internal abdominal Iliohypogastric and Flexes and rotates trunk, depreses ribs in forced oblique ilioinguinal N. expiration [fibers run superiorly and medially] Transverses Iliohypogastric and Compresses abdominal contents, depresses ribs abdominis ilioinguinal N. in forced expiration [fibers run horizonally] Rectus abdominis Lower 6 thoracic N. Flexes trunk, depresses ribs in forced expiration Pyramidalis T12 spinal N. Tenses linea alba Cremaster Genital br. of Retracts testis genitofemoral N. Clinical notes Ascites  Accumulationof fluid in peritoneal cavity and may be caused by peritonitis or result from congestion of venous drainage of the abdomen. Important features of the abdominal wall Name Features Linea alba Fusion of aponeurosis of transverses abdominis, internal & external oblique Linea semilunaris Crosses costal margin near tip of 9th costal cartilage Arcuate line Lies midway between umbilicus and pubis Inguinal ligament Aka Poupar’s ligament, it fuses inferiorly w/ fascia lata of thigh Lacunar ligament Aka Gimbernat’s ligament, continuous w/ pectineal line w/ pectineal ligament [cooper’s ligament] Conjoint tendon Fusion of transverses abdominis and internal oblique aponeurosis, it also strengthens abdominal wall behind the superficial inguinal ring Rectus sheath Contains the superior and inferior epigastric arteries and distal portions of thoracoabdominal,subcostal and iliohypogastric nerves, formed by fusion of poneurosis of transverses abdominis, internal / external abdominal oblique Arcuate line Marks the point where all aponeurosis pass anterior to rectus abdominis M, located btw umbilicus and pubic symphysis. Topography of the anterior abdominal wall Plane Dividions Vertical planes Transpyloric and R and L lateral planes Horizontal Transpyloric plane planes Intertubercular plane Lateral planes R hypochondriac L hypochondriac R lateral lumbar region R inguinal iliac region L inguinal iliac region Midline planes Epigastric region Umbilical region Hypogastric/pubic region

Notes & contents Approximate the midclavicular lines of thorax and extend caudally to midpoint of inguinal ligament Midway between jugular notch and pubic symphysis Passes thru the tubercles of iliac creast Containing the liver Containing the fundus of stomach and spleen Containing the descending colon Containing ileocecal junction and appendix Conaining the sigmoid colon Containing the liver stomach and pancreas, Containing the small intestine, transverse colon and greater omentum Containing the small intestine, full urinary bladder, or pregnant uterus.

Blood vessels of the anterior abdominal wall A. Arteries Name Features Superior epigastric A. From terminal branch of internal thoracic A. Inferior epigastric A. From external iliac A., Branches: cremasteric A., pubic branch Deep circumflex iliac A. From external iliac A., supplies lower part of abdominal wall Superficial epigastric A. Supplies inferior + medial parts of the superficial abdominal wall Superf circumflex iliac A Supplies inferior + lateral part of the superficial abdominal wall Superf external pudendal A Supplies the lower abdominal wall over the mons pubis B. Veins [refer to Netter p. 239] Name Drains External iliac V. Inferior epigastric and deep circumflex iliac V. Femoral V. Superf circumplex iliac, superf epigastric and superf ext pudendal V. Superior epigastric Brachiocephalic V. Thoracoepigastric Important anastomotic connection btw superior and IVC Superficial epigastric Femoral vein and communicate w/ small paraumbilical V. Superf circumflex iliac Femoral veins Deep circumflex iliac Internal thoracic and external iliac veins Clinical notes Varocosity of the superficial epigastric veins

 Obstruction of either the IVC or hepatic portal vein, both of w/c drain structures below the diaphragm may result in varicosities of superficial epigasric veins.

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C. Nerves [from ventral rami of T7-L1 spinal nerves] Name Origin Thoracoabdominal N. Ventral rami of T7-T11 Iliohypogastric and ilioinguinal N. Ventral ramus of L1 D. Lymphatic drainage of anterior abdominal wall Anterior axillary LN Cutaneous vessels Above level of umbilicus Superficial inguinal LN Cutaneous vessels below evel of umbilicus PERITONEUM  Serous membrane that lines the abdominal and pelvic cavities  Parietal peritoneum lines the walls, for pain, temperature, touch and pressure, innervated by lower 6 thoracic and 1st lumbar nerves, and obturator nerve in pelvis.  Visceral peritoneum covers abdominal organs, for strength only, innervated by autonomic N. Clinical notes Inflammation of parietal peritoneum  This results in sharp, localized pain over the affected area.

 Pxs may exhibit rebound tenderness [pain elicited after pressure of palpation over affected area is moved] and guarding [reflex spasms of abdominal musces in response o palpation] over site of inflammation. Peritoneal irritation

 Irritation of peritoneum covering the diaphragm may result in pain being referred to C3, 4, 5 dermatomes in region of neck and shoulder. Peritoneal ligaments and mesenteries Greater omentum Is the dorsal mesentery of the stomach, it prevents spread of infection by adhering to and localizing aeas of inflammation [abdominal policeman] Gastrocolic lig. Attached to greater curvature of stomach and 1st part of duodenum, contains the gastroepiploic arteries Gastrolienal lig. Aka gastrolienal lig., from greater curvature of stomach to hilus of spleen Gastrosplenic From greater curvature to spleen, separates L greater & lesser sacs Lienorenal lig. From hilus of spleen to L kidney, contains the splenic A. & V. Gastrophrenic lig. Connect esophagus and fundus of stomach to undersurface of diaphragm Lesser omentum Ventral mesentery of stomach, from septum transversum Hepatogatric lig. Between lesser curvature of stomach and liver, contains the R and L gastric arteries and veins near the stomach Hepatoduodenal lig. Between 1st part of duodenum and anterior border of epiploic foramen, contains the CBD, proper hepatic A., and portal V. [portal triad] Other structures Phrenicocolic lig. Connects L colic flexure to diaphragm, limits the paracolic gutter Falciform lig. Connects liver to anterior abdominal wall above umbilicus, contains the ligamentum teres hepatis [remnant of L umbilical V. of the fetus] Mesentery proper Attaches small intestine from duodenojejunal flexure to ileocecal junction Transverse Attaches to transverse colon from L to R colic flexures and to anterior mesocolon surface of pancreas, it normally fuses w/ gastrocolic ligament to form the definitive transverse mesocolon, it contains the middle colic A. and V. Sigmoid mesocolon Attaches sigmoid colon from L iliac fossa to pelvis, contains sigmoidal V Mesoappendix Suspends vermiform appendix and transmits the appendicular A. and V. Ligament of Treitz Aka suspensory ligament of duodenojejunal junction PERITONEAL CAVITY [refer to Netter p. 258]  A completely closed cavity in males, but open in females thru the uterine tube, uterus & vagina Greater sac Extends from diaphragm to pelvis, communicates w/ lesser sac thru foramen of WINSLOW or epiploic foramen Hepatorenal recess Aka MORISON’S POUCH, lies btw R lobe of liver and R kidney Paracolic gutters Provide potential pathway for spread of infection Lesser sac Aka as omental bursa, develops as evagination of dorsal mes. Inferior recess Extends beyond stomach into the layers of greater omentum Splenic recess Extends behind stomach, btw gastrosplenic lienorenal lig. Superior recess From diaphragm behind L lobe of liver,btw IVC and esophagus Epiploic foramen of WINSLOW  Communication between greater and lesser peritoneal sacs  Anterior: hepatoduodenal ligament [contains CBD, proper hepatic A., and portal V.]  Posterior: inferior vena cava  Superior: caudate lobe of liver  Inferior: 1st part of duodenum STOMACH [refer to Netter p. 258]  Anchored by esophagus proximally and duodenum posteriorly  Located in epigastric and L hypochondriac regions of the abdomen  Blood supply: L gastric [from celiac] & R gastric A [from hepatic], L gastroepiploic [from splenic] & R gastroepiploic A. [from hepatic], short gastric A.  w/ accompanying veins that drain to the portal vein or its tributaries

 Lymphatics: Area 1 = aortic nodes [2/3], Area 2 = subpyloric nodes & Area 3 = greater curvature  Nerve supply: celiac plexus [sympathetic] and vagus N. [parasympathetic] Clinical notes Surgical access to omental bursa  This may be obtained by incising lesser omentum, gastrocolic or gastrosplenic ligament.  The middle colic A. w/c courses in gastrocolic ligament would have to be avoided in surgery  Short gastric A. and L gastroepiploic A. w/c course in gastrosplenic ligament would have to be avoided in surgery. Gastric carcinoma  Commonly develop in pyloric part and metastasize to cisterna chylli and thru thoracic duct to L brachiocephalic vein.  An enlarged L supraclavicular node of Virchow may act as a sentinel node for gastric CA.  CA of stomach that metastasizes to ovaries is known Krukenberg tumors. DUODENUM [refer to Netter p. 261]  Is the shortest [25 cm] but widest part of small intestine Duodenum From pylorus to jejunum, retroperitoneal [except for its most proximal and most distal parts], lies at level of L1-2, surrounds the head of pancreas st 1 part [sup] W/ duodenal cap or bulb, joined to liver by free edge of hepatoduodenal lig. nd 2 [descend] Descends vertically to the R of the bodies of L1,2,3 rd 3 [transverse Crosses anterior to body of L3 th 4 [ascend] To L side of the body of L2 and end at duodenojejunal flexure  Blood supply of duodenum: [refer to Netter p. 283] Name Anterior and posterior superior pancreaticoduodenal A. Anterior and posterior inferior pancreaticoduodenal A. Supraduodenal and retroduodenal A.

Origin Gatric A. Superior mesenteric A. Gastroduodenal A.

 Lymphatics: pancreaticoduodenal nodes → gastroduodenal nodes → celiac nodes → superior mesenteric nodes  Nerve supply: vagus N. [via celiac and superior mesenteric plexuses] Clinical notes Duodenal compression  The superior mesenteric vessels may compress the horizontal part of duodenum. Pxs experience epigastric or umbilical pain, nausea after a meal, and billous vomiting. Gastrointesinal bleeding  Hematemesis [vomiting of blood], results from bleeding into esophageal lumen, stomach, or duodenum proximal to ligament of Treitz. It is commonly caused by duodenal or gastric ulcer and esophageal varices.  Hematochezia [blood in stool] usually results from bleeding into lumen of jejunum, ileum, colon or rectum distal to ligament of Treitz.  Melena [black, tarry stools] that contain blood altered by gastric secretions. In melenamesis, there is “coffee-ground” vomitus. Celiac A. occlusion & collateral circulation & effects of ulcers  In occlusion of celiac A. at its origin from abdominal aorta, collateral circulation ay develop in pancreatic head by way of anastomoses btw pancreaticoduodenal branches of both superior mesenteric and gastroduodenal arteries. 3 branches of celiac circulation may be subject to erosion if an ulcer penetrates posterior wall of duodenum.  The splenic A. may be subject to erosion by contents of a penetrating ulcer of posterior wall of stomach.  The L gastric A. may be subject to erosion by contents of a penetrating ulcer of the lesser curvature of stomach.  The gastroduodenal A. may be subject to erosion by contents of a penetrating ulcer of the posterior wall of 1st part of duodenum.  Pxs w/ penetrating ulcer may have pain referred to shoulder w/c occurs when air escapes thru the ulcer and stmulates the peritoneum covering the inferior aspect of diaphragm.  The contents of a penetrating ulcer of posterior wall of stomach or duodenum may enter omental bursa. The fluid contents from an ulcer may pass thru epiploic foramen into subhepatic recess [MORRISON’S POUCH], the part of greater peritoneal cavity situated btw posterior aspect of liver and R kidney. JEJUNUM AND ILEUM Jejunum Larger and thicker than ileum, w/ abundant plicae circulares and diffuse [2 m] lymphoid tissue, less fat, deep red color, greater vasculature, fewer arterial arcades Ileum Smaller and thinner than jejunum, paler pink color, less vvascularity, short vasa [3 m] recta, fewer plicae circulres, numerous peyer’s patches and arcades, more fat  Both are approximately 20 ft in length [8ft – jejunum, 12 ft – ileum]  Blood supply: anastomosing branches of superior mesenteric A. & by superior mesenterc V. w/c joins the portal V.  Lymphatics of jejunum: superior and inferior mesenteric nodes  Nerve supply: vagus nerve fibers [from superior mesenteric plexus]

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Clinical notes Meckel’s diverticulum  Fingerlike true diverticulum from antimesenteric side of ileum about 2-3 ft. from ileocecal junction  Represents persistence of fetal vitelline duct /omphalomesenteric duct, in 2% of population, 2 inches long, and may contain ectopic gastric or pancreatic cells.  It may also retain a connection w/ umbilicus of newborn allowing feces to leak from the umbilcus [meckel’s fistula]  A diverticulum is an outpocketing of a tubuar or saccular organ such as GIT or bladder. True diverticula are protrusions that include all layers of affected structure; while false or pulsion diverticula are protrusions that do not contain all tissue layers.  Pxs may have bleeding associated w/ ulceration of ectopic cells, obstruction and pain that is referred over the area of umbilical region in T10 dermatome. LARGE INTESTINE [refer to Netter p. 254]  4-5 ft long, characterized by tenia coli [3 narrow bands of longitudinal muscle], haustra coli [sacculations], and appendices epiploicae [small sacs of peritoneum] Cecum [6 cm] Blind pouch, covered by peritoneum and lies free in peritoneal cavity, has an ileocecal valve [rudimentary valve] and ileocecal orifice, attached posteriorly to vermiform appendix Blood supply: anterior & posterior cecal A. [from ileocecal A.] & SMA & is drained by superior mesenteric vein to portal vein Lymphatics: superior mesenteric nodes Nerve supply: vagus N. via superior mesenteric plexus Vermiform Usually 10-12 cm, completely covered by peritoneum, suspended from appendix [9 terminal ileum by mesoappendix, completely infiltrated by lymphoid tissue w/ cm] complete layer of longitudinal muscle derived from convergence of tenia coli, supplied by appendicular A. & V. [from post. cecal branch of ileocolic A.] Colon Ascending From ilocecal valve to R colic [hepatic] flexure below liver, its posterior side is [12-20 cm] fused to posterior abdominal wall, is related to R paracolic gutter Is supplied by ileocolic A. and R colic A. [from superior mesenteric A.] Transverse From R colic [hepatic] flexure to L colic [splenic] flexure, suspended from [50 cm] posterior wall by transverse mesocolon, is also suspended at L colic flexure by phrenicocolic ligament, related to R of liver and L of spleen Supplied by middle colic A. [from superior mesenteric A.] Descending From L colic flexure to pelvic brim, its posterior side is fused to the posterior [25 cm] abdominal wall; it is supplied by L colic A. [from inferior mesenteric A.] Sigmoid Begins in iliac fossa at pelvic brim as continuation of the descending colon, [40 cm] continuous w/ rectum at level of S3, suspended by sigmoid meocolon, is supplied by sigmoidal A. [from inferior mesenteric A.] drained by sigmoidal V. Rectum At S3 level, no haustra or appendices epiploicae, w/ valves of HOUSTON [12-15 cm] Supplied by superior rectal A. [from inferior mesenteric A.], middle [from inferior vesical A.] and inferior rectal A. [from internal pudendal A.] Drained by superior rectal V. and anastomoses w/ middle and inferior rectal V. Innervated by pelvic splanchnic N. and inferior hypogastric plexus Lymphatics: pararectal nodes [superior], internal iliac nodes [inferior] Clinical notes Appendicitis  The vermiform appendix may become inflammed as a result of either an obstrucion by fecalith [adults] or lymphoid hyperplasia [children].  An inflamed appendix may stimulate visceral pain fibers w/c course back in lower splanchnic N. and result in colicky pain referred over umbilical region.  Irritation of parietal peritoneum may result in pain localized over the base of appendix [McBurney’s point – btw ASIS and umbilicus in RLQ].  S/Sx: [+] psoas sign on R, where pain from irritated parietal peritoneum is accentuated when the R thigh is extended at hip against resistance.  A [+] obturator sign on R, where pain from irritated parietal peritoneum is accentuated when R thigh is flexed and then internally rotated.  The iliohypogastric nerve may be lesioned in an appendectomy procedure; a weakenng of anterior abdominal wall & a direct inguinal hernia may result. Intestinal intussusception  Part of the small intestine invaginates or telescopes into adjacent distal segment [intussuscipiens]  May be jejunoileal, ileoileal, or MC an ileocecal where distal part of ileum telescopes into ascending colon.  It is more commn in children than in adults and may be caused by hyperplasia of lymphatic tissue in Peyer’s patches in ileal wall.  Pxs may have an obstructed bowel, R sided colicky pain, abdominal distention and hematochezia because blood supply to intussuscepted ileum may be compromised. Sigmoid volvulus, diverticulosis, & diverticulitis  Sigmoid volvulus, the sigmoid colon twists around sigmoid mesocolon and may become obstructed.  This pxs may experience L sided colicky pain, abdominal distention, and hemaochezia as a resut of compromise of he sigmoid arteries.  Diverticulosis refers to diverticula that are not inflamed.

 Diverticulitis refers to inflammed diverticula. If a diverticulum ruptures, the ruptured contents may irritate the parietal peritoneum resulting in pain that is localized to LLQ. Ischemic bowel infarction  Common sites: transverse colon near splenic flexure, and rectum  Infarction of transverse colon occurs btw middle colic branches of SMA & L colic branches of IMA.  Infarction of rectum occurs btw superior rectal branches of IMA and middle rectal branches of internal iliac A. Hirschprung’s disease  Caused by failure of neural crest cells either to migrate into hindgut or to differentiate into terminal parasympathetic ganglia in walls of hindgut.  Pxs experience constriction in the affected segment [often rectum], an absence of peristalsis and a dilated large bowel proximal to affected segment.  This is common in pxs w/ Down’s syndrome. Differences btw small and large intestine Small intestine Large intestine More mobile [except duodenum] Less mobile w/ mesentery [except duodenum] w/o mesentery Intraperitoneal Retroperitoneal [except transverse & sigmoid] Smaller diameter Larger Continuous layer of longitudinal muscle Longitudinal uscles forms 3 bands [taenia coli] No fatty tags in its wall w/ fatty tags [appendices epiploicae] Smooth wall Sacculated wall [haustrae] w/ permanent folds [plicae circulares] Absent w/ peyer’s patches Solitary lymph follicles w/ villi Absent villi LIVER  Largest visceral organ, weighing about 1.5 kg  Enclosed by fibrous capsule and covered by visceral peritoneum [except where it directly contacts the underside of the diaphragm] Surfaces of liver Diaphragmatic surface Consists of anterior, superior and posterior surfaces, it has a bare area w/c directly contacts the diaphragm Visceral surface In the inferior surface and is contact w/ abdominal organs Inferior border Is where the visceral and diaphragmatic surfaces meet Bare area Is in direct contact w/ the: diaphragm, IVC, R suprarenal gland & superior pole of R kidney Space of Disse Separates sinusoidal wall from liver cell plates where exchange of nutrients & waste products takes place Lobes of liver [refer to Netter p. 270] R lobe Largest lobe, lies to the R of gallbladder and the IVC L lobe Lies to the L of the falciform ligament, and the fissures of ligamentum venosum and ligamentum teres on its visceral surface Caudate lobe Functionally part of the L lobe, lies posterior to porta hepatic btw groove for IVC and fissure for ligamentum venosum Quadrate Functionally part of L lobe, lies anterior to porta hepatis btw fossa for lobe gallbladder and fissure for ligamentum venosum  Features of the visceral surface of the liver Porta hepatis Is the hilus of the liver, a transverse fissure that separates caudate and quadrate lobes, it transmits the R and L hepatic ducts, R and L hepatic A., R and L branches of portal vein, autonomic plexus, and LN Fissure for lig. Contains ligamentum venosum [remnant of ductus venosus] w/c Venosum bypasses liver by shunting blood from portal and umbilical V. Fissure for lig. Contains the ligamentum teres hepatis [remnant of L umbilical V.] w/c teres carries blood returning to the fetus from the placenta Clinical notes Cirrhosis  Obstruction of portal vein and HPN in portal system is caused by destruction of hepatocytes and its replacement by fibrous tissue.  Pxs may develop portal HPN, in w/c venous blood from GIT w/c normally enters the liver via portal vein is forced to flow in the opposite or retrograde direction in tributaries of portal vein.  Esophageal varices are dilated and tortous veins that develop in submucosal venous plexus in esophageal wall. This may burst and result in hematemesis.  Internal hemorrhoids are painless protrusions of anal canal covered by mucosa. It contains dilated veins of internal rectal venous plexus.  Caput medusae is a pattern of varicose superficial epigastric veins that radiate away from umbilicus.  Splenomegaly is also a common sign associated w/ pxs having portal HPN. Peritoneal ligaments of the liver Falciform ligament Double layer of peritoneum, attaches to anterior abdominal wall to the

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Coronary ligament R triangular lig. L triangular lig.

undersurface of the diaphragm, derived from septum transversum Reflection of visceral peritoneum of liver onto undersurface of diaphragm Joins the R lobe to undersurface of diaphragm Joins L lobe to undersurface of the diaphragm, lies anterior to esophagus

Blood supply of liver [refer to Netter p. 284] = study portal vein tributaries p. 297 Name Origin Branches Proper hepatic A Common hepatic Divides into R and L hepatic arteries, 20% of blood R hepatic A. Proper hepatic A. To R lobe, Cystic A. [to GB] in the angle btw cystic duct & CBD called hepatocystic triangle of CALOT L hepatic A. Proper hepatic A. Supplies the L lobe, quadrate and caudate lobes Portal vein SMV + splenic V. w/ R and L branches, carries 80% of blood to liver Hepatic veins [3] Drain the hepatic sinusoids, empty directly into IVC Lymphatic drainage of liver: celiac nodes and posterior mediastinal nodes Nerve supply of liver: Sympathetic and parasympathetic [vagal] fibers from celiac plexus & L vagus to large hepatic branches w/c travels directly to liver. BILIARY SYSTEM [refer to Netter p. 276] Gallbladder Stores and concentrates bile, w/ 30 ml volume, divided into fundus, body and neck, lies btw R lobe and quadrate lobe of liver. Has a Hartmann’s pouch [infundibulum]. Lymphatic drainage: cystic LN, hepatic LN and celiac LN. Nerve supply: celiac nodes Bile ducts Common hepatic Union of R & L hepatic ducts, accompanied by portal V. & proper hepatic A. Cystic duct Connects neck of GB to common hepatic duct, it is lined by spiral folds [spiral valve of REISTER] w/c keeps lumen always open Union of common hepatic duct and cystic duct, pierces head of pancreas and Common bile duct joins w/ main pancreatic duct to form hepatopancreatic ampulla of VATER, it opens into 2nd part of duodenum at the major duodenal papilla PANCREAS [p. 279] Both an exocrine [w/ ducts, producing enzyme] and endocrine organ [ductless, producing hormones], it lies at the level of L1, supplied by splenic A. and superior + inferior pancreaticoduocenal arteries and pancreatic vein to portal V. Lymphatic drainage to pancreas. Lymphatics: celiac & superior mesenteric LN. Nerve supply to pancreas: Sympathetic & parasympathetic innervation from vagus N. thru celiac plexus Head w/ hook-like uncinate process behind superior mesenteric vessels Neck constricted where it is crossed by superior mesenteric vessels Body lies above and to the left of duodenojejunal flexure Tail lies in the lienorenal ligament [peritoneal] and ends a hilus of the spleen Main pancreatic duct Opens into the 2nd part of duodenum at MAJOR duodenal papilla, it of WIRSUNG traverses the CBD to form thehepatopancreatic ampulla of VATER Accessory duct of Drains the uncinate process, and lower part of head of pancreas, opens into SANTORINI 2nd part of duodenum at the MINOR duodenal papilla SPLEEN [p. 281] Largest lymphatic organ, lies through the diaphragm along axis of ribs 912. Functions: graveyard of RBC, w/ Hassal’s corpuscles & part of RES. It is supplied by splenic A. [from the celiac trunk]. Lienorenal ligament Contains tail of pancreas and splenic A. + V. Gastrosplenic lig. Contains L gastroepiploic A.+ V. and short gastric A. + V. NOTE: sphincter of Oddi closes w/ morphine sulfate thus C/I in acute cholecystitis & inferior wall MI Clinical notes Fractured ribs & spleen  A fractured 9th, 10th, or 11th rib on the L may lacerate the spleen. The spleen bleeds profusely when lacerated and is usually removed. Gallstones  May become lodged in biliary ducts or in gallbladder.  The hepatopancreatic ampulla, a narrow point in biliary duct system, is a common site of impacted gallstones. Pxs exhibit referred pain in epigastric area.  Stone blocking cystic duct may cause enlargement of gallbladder. Pxs may exhibit biliary colic [severe colicky pain that begins in epigastric area but moves to a point where 9th costal cartilage intersects the lateral border of rectus sheath.  An inflammed gallbladder may adhere to duodenum and develop a fistula, permitting a gallstone to pass into duodenum. The gallstone may become lodged at ileocecal junction forming a gallstone ileus. Pancreatic adenocarcinoma  MC at pancreatic head and may result in compression of bile ducts & main pancreatic duct.  S/Sx: epigastric pain that frequently radiates to the back, obstructive jaundice  If the main pancreatic duct is obstructed, the pancreas may become inflamed; pxs w/ acute pancreatitis may experience localized ileus in duodenum adjacent to area of inflammation.  TOC: Whipple’s [TOC]  Pringle’s maneuver – poke your finger in pancreas  5 year survival rate = 3-5% [lowest rate]

KIDNEY [refer to Netter p. 311]  Retroperitoneal organ lying adjacent to upper 3 lumbar vertebrae  On right side, extends superiorly to level of 12th rib and on left side to the level of 11th rib  R kidney is lower than L because of R lobe of liver  Hilum transmits from front to backward: renal V., 2 branches of renal A., ureter and 3 rd branch of renal A.  Coverings: fibrous capsule [outer], preirenal fat, and renal fascia, pararenal fat [outer] & has a parenchyma divided into cortex and medulla  Supplied by renal arteries [from abdominal aorta] and veins [drains to IVC at L2 level]  Lymphatic drainage: lateral aortic nodes  Nerve supply: renal sympathetic plexus [T101-12] URETER  Muscular tube that transports urine from renal pelvis to urinary bladder  Is most likely to become obstructed [ureteral constrictions] where it joins the renal pelvis, crosses the pelvic brim or enters the bladder wall  Function: propels urine from renal pelvis to urinary bladder  In female, lies in the base of the broad ligament where it is crossed anteriorly and superiorly by uterine A. In male, it is crossed superiorly by ductus deferens near the bladder  The prostatic urethra is the widest and most dilatable part, while the membranous urethra is the shortest and least dilatable part. External urethral meaus is the narrowest part.  Receives blood supply from renal A. [upper 3rd] common iliac A. [middle 3rd] and superior vesical A. [distal 3rd], drained by similar veins  Lymphatic drainage: lateral aortic and iliac nodes  Nerve supply: ureteric plexus [from aortic plexus]  Associated w/ pain referred to cutaneous distribution of T11-12, particularly to lower abdominal wall, external genitalia, and medial thigh Clinical notes Kidney transplantation  In kidney transplants, only the upper part of ureter supplied by renal A. is transplanted w/ renal vessels and the kidney. The kidneys are placed in the pelvis, where the upper part of ureter is attached to the bladder and the renal A. is joined to external iliac A. Ureteral calculi  A calculus may become lodged at 1 of 3 narrow points in the ureter and results in a hydronephrosis proximal to the site of the blockage. Renal colic  A severe type of colicky pain that results from distention of ureter by a calculus referred over T11 thru L2 dermatomes. The pain may radiate from back above iliac crest thru the inguinal region and into scrotum or labium majus. RENAL FAT AND FASCIA [refer to Netter p. 313]  Support and cushion the kidney & provides compliance for movement occurring during respiration Renal fascia Surrounds the kidney and suprarenal gland Perirenal fat Lies between capsule of kidney and renal fascia Pararenal fat Lies outside renal fascia Blood vessels of kidney [refer to Netter p. 314] Renal arteries From abdominal aorta, 1 to each kidney Anterior branch Divides into upper, middle and lower segmental A. Posterior branch Divides into posterior segmental A. Apical segmental A. From upper segmental A. Segmental A. Are end arteries, will result to death if occluded R renal A. Passes posterior to Inferior vena cava Accessory renal A. Are segmental A. that do not reach the kidney thru renal hilus Renal veins L renal V. R renal V.

From IVC, 1 from each kidney Longer than the R, receives terminations of L suprarenal V. and L gonadal V. Shorter, passes posterior to 2nd part of duodenum and head of pancreas

URINARY BLADDER  Highly distensible muscular organ  Parts: apex, base, superior surface and neck  Muscles of bladder wall: detrusor muscles composed of inner and outer longitudinal layer and a middle circular layer, it surrounds the uretra as the circularly-arranged sphincter vesicae  Space of Retzius: btw pubic bones & bladder, limited below by pubovescial ligament [F] & puboprostatic ligament [M]  Supplied by superior & inferior vesical A. [from internal iliac] & drained by same veins  Lymphatics: external iliac LN [anterior] & internal iliac LN [posterior]  Innervated by hypogastric plexus [filling nerves] & pelvic splanchnic N. [emptying nerves] Relations Female Male Infero-laterally Prevesical space of Retzius Prevesical space of Retzius Posteriorly Vagina & cervix, separated by Recum, separated by 2 seminal vesicles & vesicovaginal septum ductus deferens & by Denonvillier’s fascia

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Inferiorly Superiorly

Ress directly on pelvic floor Covered by peritoneum

Rest directly on pelvic floor Covered by peritoneum

SUPRARENAL GLAND  Paired retroperitoneal organ on upper pole of kidney, surrounded by perirenal fat & fibrous capsule  R suprarenal is pyramidal-shaped, L suprarenal is cresentic  Lymphatics: lateral aortic nodes  Innervated by splanchnic nerves  Blood supply: Superior suprarenal A. From inferior phrenic A. Middle suprarenal A. From abdominal aorta Inferior suprarenal A. From renal A. Single suprarenal V. Terminates on the R into the IVC, and on the L into L renal V. 1◦ regulatory control Renin-angiotensin ACTH, hypothalamic CRH ACTH, hypothalamic CRH Preganglionic symph. fibers

Anatomy Zona Glomerulosa of cortex Zona Fasciculata of cortex Zona Reticularis of cortex Adrenal medulla [chromaffin cells]

Secretory products Aldosterone Cortisol, sex hormones Sex hormones, androgens Catecholamines [NEp, Ep]

Clinical notes Aortic aneurysm  MC site: proximal to bifurcation of aorta at L4 level. Pxs may have pulsating painless mass in the midline. Muscles of the posterior abdominal wall [refer to Netter p. 246] Name Innervation Actions Psoas major Ventral rami of L1-2 Flexes and medially rotates thigh Psoas minor Ventral ramus of L1 Flexes trunk Iliacus Femoral N. Flexes and medially rotates thigh Quadratus lumborum Ventral rami of T12, L1-3 Depresses the 12th rib Nerve supply on posterior abdominal wall Iliohypogastric N. [L1] With anterior and lateral cutaneous branches Ilioinguinal N. [L1] Gives cutaneous branches to upper medial thigh, scrotal, or labial branches Genitofemoral [L1,2] Divides into genital [scrotum/labia majora + cremaster M.] & femoral br. [skin] Femoral N. [L2-4] Largest branch of lumbar plexus, divides into its terminal branches just below the inguinal ligament Clinical notes Compression of ureter  The proximal part of ureter may be compressed by an aberrant renal artery; w/c commonly arises from inferior to renal artery and passes anterior to origin of ureter causing hydronephrosis.  A male px w/ varicocele [often on L], resulting from compression of L renal vein by an aneurysm of superior mesenteric artery near origin of the artery from the abdominal aorta. Lymphatics on posterior abdominal wall Preaortic node Divided into celiac, superior & inferior mesenteric nodes Lateral aortic nodes From R and L lumbar trunks Cisterna chili From intestinal trunk, R and L lumbar trunks ABDOMINAL AORTA [refer to Netter p. 247]  Enters abdomen thru aortic hiatus in diaphragm at level of T12 and descends on body of L4  3 unpaired anterior visceral branches: celiac [T12], superior [L1] & inferior [L3] mesenteric A.  3 paired lateral visceral branches Middle suprarenal A. At level of L1 to supply the suprarenal gland Renal arteries At level of L1-2, gives rise to inferior suprarenal A. Testicular/ovarian A. At level of L2-3, supplies testis [M], and ovaries [F]  5 paired lateral somatic branches to abdominal wall Inferior phrenic A. Gives rise to superior suprarenal A. Lumbar segmental A. [4 pairs] Supplies crura of diaphragm & muscles of the posterior abdominal wall, it gives rise to dorsal & spinal branches Inferior phrenic A. Other branches Median sacral A. May give rise to 5th pair of small lumbar segmental A. Common iliac A. [2] Terminal branches of aorta, lies in the body of L4 INFERIOR VENA CAVA [refer to Netter p. 248]  Union of common iliac veins and ends in R atrium  Pierces central tendon of diaphragm at T8 level.  Receives terminations of: Common iliac V.

Renal V. Lumbar segmental V. Hepatic V. R gonadal V. R suprarenal V. R inferior phrenic V.

L ends in L renal V. L ends in L renal V. L ends in L suprarenal V.

Clinical notes Compression of L renal vein  L renal vein may be compressed by aneurysm of the superior meenteric A. as the vein crosses anterior to aorta. Pxs w/ compression of L renal vein may have renal and adrenal HPN on L and a varicocele on the R [in males]. HEPATIC PORTAL VENOUS SYSTEM [refer to Netter p. 297] Main vein Terminations Notes Portal vein Splenic V., Superior and inferior Superior mesenteric + splenic mesenteric V., R and L gastric V., Cystic veins V., Superior pancreaticoduodenal V. & Paraumbilical V. Splenic vein Inferior mesenteric V., Short gastric V., L Forms at hilus of spleen and gastroepiploic or gastroomental V. & enters the lienorenal Pancreatic V. ligament Superior Tributaries corresponding to branches of Mesenteric Vein superior mesenteric A., R gastroepiploic or gastroomental V., & Inferior pancreaticoduodenal V. Inferior Superior rectal V., Sigmoidal V. & L colic Superior rectal + sigmoidal V. Mesenteric Vein V. Left Gastric Vein Drains the L side of lesser curvature of stomach and lower esophagus Right gastric Vein Drains R side of lesser curvature of stomach Paraumbilical vein Accompany the ligamentum teres hepatis in the free edge of falciform ligament & connects the L branch of portal V. to superficial V. in umbilicus Portocaval Occurs at lower end of esophagus, anal canal, umbilicus & bare areas anastomoses Arteries of the Gastrointestinal tract [refer to Netter p. 282] Name Features Celiac A. Lies anterior to body of T12, said to be the artery of foregut Splenic A. Largest branch of the celiac trunk, branches include: dorsal, great, and caudal pancreatic A., short gastric A., L gastroepiploic A. L gastric A. Smallest branch of celiac trunk; anastomoses w/ R gastric A. Common hepatic A. Give rise to gastroduodenal, R gastric, R and L hepatic A. & continues as proper hepatic A. Superior mesenteric A. Arise anterior to body of L1, said to be the artery of midgut Inferior mesenteric A. Arise anterior to body of L3, said to be the artery of hindgut Thoracoabdominal A. Branches: Clavicular, Acromial, Pectoral, Deltoid [At California Police Department] Branches of Common hepatic Artery Name Branches Gastroduodenal A. Supraduodenal, retroduodenal, post. superior pancreaticoduodenal A. Proper hepatic A. Cystic A. to gallbladder [usually from theR hepatic A.] Superior Arise as independent anterior and posterior superior pancreaticoduodenal pancreaticoduodenal A. branches from the gastroduodenal A. R gastroepiploic A. Aka as gastroomental A.,arise as terminal branch of gastroduodenal Branches of Superior Mesenteric Artery [refer to Netter p. 286] Name Branches Inferior pancreaticoduodenal A. Anterior and posterior inferior pancreaticoduodenal A. Middle colic A. Right and left branches R colic A. Ascending and descending branches Ileocolic A. Ascending colic branch, ileal branch, anterior and posterior cecal A. and appendicular A. Intestinal A. Distributed to jejunum and ileum Branches of the Inferior Mesenteric Artery [refer to Netter p. 287] Name Branches L colic A. Ascending and descending branches w/c join marginal A. Sigmoidal A. Form series of anstomosing arcades to sigmoid colon Superior rectal A. Anastomoses w/ middle rectal and inferior rectal A. Marginal A. of DRUMMOND Formed by ileocolic, R colic, middle colic, L colic and sigmoidal A. Nerves of the abdomen Name Origin Branches Vagus N. Aortic, celiac, superior mesenteric plexuses Thoracic splanchnic N T5-12 ganglia Greater, lesser and least splanchnic N. Lumbar splanchnic N. Upper lumbar Joins the celiac, sup. and inf. mesenteric plexuses Pelvic splanchnic N. S2-4 spinal N. Aka as nervi ergentes

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Autonomic plexus Lumbar symph. Trunk

Aortic plexus

Celiac, superior and inferior mesenteric plexus w/ 4 segmentally arranged ganglia [grey and white]

Clinical notes Referred pain  Stimulation of visceral pain fibers that innervate a gastrointestinal structure results in dull, aching, poorly localized pain referred over T5-L1 dermatomes.  Sites of referred pain generally correspond to spinal cord segments that provide sympathetic innervation to affected gastrointestinal structure. Colicky pain  A rhythmic, recurring pain symptomatic of ileus [obstruction of GIT]  It resuls from recurrent smooth muscle contractions against the obstruction.  Biliary or renal colic results from recurring smooth muscle contractions against a gallstone lodged in biliary system or calculous lodged in ureter. CHAPTER 6 – PELVIS AND PERINEUM PELVIS [refer to Netter p. 332] Components of the bony pelvis: paired hip bones, sacrum, coccyx Pelvic brim Aka as superior pelvic aperture or pelvic inlet, bounded by promontory of sacrum, arcuate line of ilium, and iliopectineal line of pubis Pelvic outlet Bounded by coccyx, sacrotuberous ligaments, ischial tuberosities, ischiopubic rami, & pubic symphysis, bounded by coccyx, ischial tuberosities, & pubic arch Greater pelvis Aka as false or major pelvis, forms the lowest part of abdominal cavity Lesser pelvis Aka as true or minor pelvis Sex differences in bony pelvis Feature Male True pelvis/minor/lesser Narrow and deep False pelvis/major/greater Deep Pelvic inlet Narrow, heart-shaped Pelvic cavity Longer, tapered, cone-shaped Pelvic outlet Smaller Pelvic brim Android Pubic arch Narrow Greater sciatic notch Narrower Ilium Tall, deep, narrow Shape of sacrum Longer, narrower, more curved Coccyx Fixed, pointed inwards Ischial spines Inverted, closer

Female Wide and shallow Shallow Wide, oval or rounded Short, cylindrical, roomier Larger Ovoid Wide Wider Short, shallow, wide Shorter, wider, flatter Not fixed, attached loosely More widely separated

Measurements of pelvic inlet and outlet Conjugate diameter Aka obstetric conjugate diameter or true conjugate diameter, lies between pubic symphysis and sacral promontory Oblique diameter Maximum distance between opposing arcuate lines [pelvic inlet] or the distance between ischial spines [pelvic outlet] Diagonal conjugate Between lower border of pubic symphysis and sacral promontory AP diameter of outlet Between lower border of pubic symphysis and tip of coccyx

 The smallest diameter of pelvic outlet: transverse diameter between the ischial spines  Maximum measurement of pelvic inlet: transverse diameter  Maximum diameter of pelvic outlet: anteroposterior diameter Pelvic diaphragm [refer to Netter p. 333] Coccygeus muscle Aka ischiococcygeus, innervated by S4-5 spinal N. Levator ani muscle Maintains integrity of pelvic floor, important in maintaining urinary continence and preventing uterine prolapse, innervated by S4 spinal N. Pubococcygeus w/ levator prostatae, puborectalis and pubovaginalis muscle Puborectalis Functions as sphincter to maintain anal continence Clinical notes Weakness in pelvic diaphragm  May result in prolapse of uterus into vagina or herniation of bladder or rectum into vagina.  In pxs w/ uterine prolapse, the cervix, isthmus, and body of uterus protrude into the superior aspect of vagina. Px may experience bleeding and discharge into the vagina.  In pxs w/ cystocele, the bladder herniates into upper part of anterior vaginal wall. Px may experience urinary problems.  In pxs w/ rectocele, the rectum herniates into lower part of posterior vaginal wall. Px may have difficulty in defecation.  Kegel exercises strengthen pelvic diaphragm, in particular pubococcygeus muscles to prevent prolapse or herniation of pelvic viscera. Pelvic fascia Puboprostic [M] or pubovesical [F] lig. Transverse cervical/cardinal ligament

Fills the anterior gap in levator ani [genital hiatus] Stabilize and support uterus and vagina

Sacrogenital [M] or uterosacral [F] lig.

Stabilize and support pelvic organs

Clinical notes Penile urethral laceration

 This may result in extravasation of urine into superficial perineal pouch that may spread into regions covered by extensions of Colles’ fascia. The extravasated urine may be found around penis, scrotum, and deep to Scarpas’ fascia on anterior abdominal wall. The only difference btw male perineal pouches and female perineal pouches is the location of bulbourethral glands and greater vestibular glands.

 Bulbourethral glands are situated in deep perineal pouch in males while greater vestibular glands are located in superficial pouch in females. INGUINAL REGION Superficial Triangular defect in the aponeurosis of ext. abdominal oblique. Larger in male & inguinal ring transmits spermatic cord. In female it transmits the round ligament of the uterus Deep inguinal Tubular evagination of transversalis fascia Inguinal canal Transmits the spermatic cord in male and round ligament of uterus in female, it also allows passage of ilioinguinal nerve in both sexes Femoral ring Is medial to femoral vein and lateral to lacunar ligament [w/c is an extension of inguinal ligament] Inguinal canal  Roof: transversus abdominis and internal abdominal oblique muscles  Floor: inguinal and lacunar ligament  Anterior wall: external oblique aponeurosis [medial], internal abdominal oblique m. [lateral]  Posterior wall: conjoint tendon [medial], transversalis fascia [lateral]  It is a site of potential weakness in lower abdomen  On coughing or straining as in micurition, defecation or parturition, the arching lowest fibers of internal oblique and transversus abdominis muscle contracts. Inguinal or HESSELBACH’S triangle  Medial: rectus abdominis m.  Lateral: inferior epigastric vessels  Inferiorly: inguinal ligament  Floor: transversalis fascia  Lies in the abdominal wall behind the superficial inguinal ring  Site of potential weakness for hernia Type of hernia Features Direct inguinal hernia M>F, lies passes medial to inferior epigastric vessels Indirect inguinal Passes lateral to inferior epigastric vessels, said to be congenital if hernia [MC type] associated w/ persisting processus vaginalis, female pxs may develop this at the canal of NUCK Femoral hernia F>M, enter anterior thigh after passing femoral ring deep to inguinal ligament, has the highest bowel incarceration rate of any hernia type Inner aspect of the lower abdominal wall Median umbilical fold Contains the median umbilical ligament [remnant of urachus] Medial umbilical folds Contains the mediaL umbilical ligament [remnant of umbiLical A.] Lateral umbilical folds Contains the inferior epigastric vessels Median inguinal fossa Area thru w/c direct inguinal hernia occurs Lateral inguinal fossa Depression that lies lateral to lateral umbilical fold Supravesical fossa Depression lying above the bladder on sides of median umbilical fold SPERMATIC CORD  Contents: ductus/vas deferens and its artery, testicular A. and V. [pampiniform plexus], testicular lymph vessels, cremasteric A., genital branch of the genitofemoral N. , periarterial autonomic [renal aortic] plexus, processus vaginalis remnants & loose areolar tissues  Coverings: Layers Origin Internal spermatic fascia Transversalis fascia [deep inguinal ring] Cremasteric muscle and fascia Internal abdominal oblique muscle External spermatic fascia External oblique aponeurosis [superficial inguinal ring] Femoral sheath Transversalis fascia and fascia iliaca  Blood supply: Testicular [aorta], Cremasteric [inferior epigastric], Vas [inferior vesicle] Clinical notes Cremasteric reflex  Utilizes sensory and motor fibers in ventral ramus of L1 spinal nerve.  Stroking the skin of superior and medial thigh stimulates sensory fibers of ilioinguinal nerve  Motor fibers from genital branch of genitofemoral nerve cause the cremasteric muscle to contract elevating the testis. Testicular torsion  Results in sudden onset of testicular pain and a loss of cremasteric reflex. Abnormal cysts in spermatic cord

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 A hydrocele is accumulation of serous fluid in tunica vaginalis or in a persistent part of processus vaginalis in a cord.  A hematocele is an accumulation of blood in tunic vaginalis and results from rupture of testicular blood vessels after trauma to spermatic cord or testis.  A spermatocele is a cyst containing sperm that develops in epididymis just above the testis.  A varicocele results from dilatations of tributaries of testicular vein in pampiniform plexus. It may be caused by defective valves in pampiniform plexus or by compression of a testicular vein [often on the L] in the abdomen. This is observed when the px is standing and disappear upon lying down. Palpation of plexus feels like a “bag of worms”. Testicular spasm  A malignant neoplasm of testis [MC a SEMINOMA] metastasizes directly to lumbar nodes, distinguishing it from a malignancy in scrotum, w/c metastasizes initially to superficial inguinal nodes. A malignancy is the MC cause of painless testicular mass. Cryptorchidism  Refers to faiure of 1 or both testes to descend completely in scrotum. The MC location is in the inguinal canal. If cryptorchidism is bilateral, the px may be sterile. Other structures of spermatic cord Pampiniform plexus of Merges in inguinal canal to form a single testicular vein at deep veins [10-12] inguinal ring Cremasteric artery From inferior epigastric A. to enter deep inguinal ring Artery of ductus From superior vesical artery to enter deep inguinal ring, it supplies deferens ductus deferens and epididymis Testicular artery From abdominal aorta Processus vaginalis Evagination of parietal peritoneum into the inguinal canal and scrotum in fetus, promotes hernial occurrence, if persisent it forms the canal of NUCK in females Gubernaculums testis From inguinal ligament of mesonephros, is homologous to round ligament of uterus and ovarian ligament proper of Female Male external & internal genitalia [refer to Netter p. 361] PENIS  Male organ of copulation

 Surrounded by superficial and deep penile fascia [buck’s]  Suspended by suspensory ligament of penis to pubic symphysis and fundiform ligament to anterior body walldivisions: body and root

 Crus of penis is an erectile tissue covered by ischiocavernus muscle  Bulb of penis is covered by bulbospongiosus muscle and contains the spongy uethra and ducts of bulbouretral glands Clinical notes Hypospadias

 Abnormal penile urethra opening on inferior [ventral] side due to failure of urethral folds to close. Epispadias

 Abnormal penile urethral opening on superior [dorsal] side due to faulty positioning of genital tubercle. SCROTUM  Derived from continuation of of skin and fascia of lower abdominal wall into peritoneum  Contents on each side: testis, epididymis, spermatic cord and coverings  Layers: o Skin

o Superficial fascia or dartos layer [functions to elevate scrotum to conserve heat] o External spermatic fascia [from external oblique] o Cremasteric fascia [from internal obique] o Internal spermatic fascia [from transversalis fascia] o Tunica vaginalis  Blood supply: superficial and deep external pudendal A. [from femoral A.] and posterior scrotal A. [from internal pudendal A.]  Innervation: anterior scrotal branch of ilioinguinal N., genital branch of genitofemoral N., posterior scrotal branches of the perineal branch of pudendal N., perineal branch of posterior femoral cutaneous N. TESTIS  Measures 4 x 3 x 2.5 cm and lies in floor of the scrotal sac, covered by tunica albuginea and tunica vaginalis testis [may accumulate serous fluid [hydrocele] or blood [hematocele]  Responsible for spermatozoa and testosterone production  Tubular structure, 4-5 m in length  Promotes sperm maturation & motility

EPIDIDYMIS [refer to Netter p. 238]  Formed by duct of epididymis and continuous at the tail w/ ductus deferens  w/ coiled tubules about 20 ft long [6 meters] Blood supply of testis and epididymis Testicular A. From abdominal aorta Testicular V. Emerges as pampiniform plexus R testicular Vein Drains to IVC L testicular Vein Drains to L renal vein Lymphatic drainage Para-aortic nodes Clinical notes Fibromatosis of Buck’s fscia  May cause Peyronies disease, w/c results in an abnormal curvature of the penis and painful erections. SEMINAL VESICLE [refer to Netter p. 338]  Unites w/ ductus deferens near base of prostate to form ejaculatory duct  Do not store spermatozoa but it produces seminal fluid w/c imparts alkalinity to the ejaculate, it also contains fructose that is nutritive to spermatozoa  Supplied by inferior vesical and middle rectal A., drained by similar veins  Lymphatics: internal iliac nodes  Innervated by superior lumbar, hypogastric and pelvic splanchnic N. DUCTUS OR VAS DEFERENS  Dilated part [ampulla], ends by joining the duct of seminal vesicle to form ejaculatory duct  Supplied by deferential A. [from inferior vesical A.], drained by similar veins  Lymphatics: external iliac nodes  Innervated by inferior hypogastric plexus EJACULATORY DUCT  Union of ductus deferens and duct of seminal vesicle  Opens into prostatic urethra on colliculus seminalis lateral to prostatic utricle  Supplied by deferential A. [from inferior vesical A.], drained by similar veins  Lymphatics: external iliac nodes  Innervated by inferior hypogastric plexus PROSTATE GLAND  Opens into prostatic sinus, a recess in prostatic urethra along colliculus seminalis  Divided into anterior, middle and posterior lobes [easily palpated during DRE]  Prostatic utricle [remnant of fused paramesonephric ducts]  Supplied by prostatic A. [from internal iliac A.], drained by prostatic venous plexus  Lymphatics: internal iliac and sacral nodes  Innervated by pelvic splanchnic N. [S2-4] and inferior hypogastric plexus Clinical notes Benign prostatic hyperplasia  It commonly occurs in periurethral zone of prostate and will result in obstruction of prostate urethra w/c may impede urinary flow and result in incomplete emptying of the bladder.  Pxs may have difficulty initiating urination and an increased need to urinate. Prostate adenocarcinoma  It commonly develops in peripheral part of prostate [MC in posterior part]. Urine flow may be altered and pxs may pass blood in urine.  It frequently metastasizes to bones of the pelvis and to bodies of vertebrae.  They also have elevated blood levels of prostatic acid phosphatase and PSA. Female internal & external genitalia [refer to Netter p. 367] CLITORIS  Homologue of penis and consists of erectile tissue, highly sensitive like the glans penis  Attached to symphysis by suspensory ligament of clitoris LABIA MAJORA  Homologous to scrotum in males, unite at the anterior labial commissure  Contain the terminations of the round ligament of the uterus LABIA MINORA  Hairless and contain no fat unlike majora, join posteriorly to form the fourchette  Divides anteriorly into prepuce and frenulum of the clitoris VESTIBULE OF VAGINA  Contains the openings of urethra, vagina, ducts of greater vestibular glands BULB OF VESTIBULE  Homologue of the bulb of penis and is divided into an erectile tissue that lie on either side of the vaginal opening

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GREATER VESTIBULAR GLAND OR BARTHOLINS GLANDS  Mucus secreting glands homologous to bulbourethral glands in males  Lies in the superficial perineal pouch and provides lubrication for coitus OVARY [refer to Netter p. 345]  w/ fibrous capsule called tunica albuginea, covered by germinal epithelium  attached to posterior aspect of broad ligament by mesovarium  suspended from lateral pelvic wall by suspensory ligament of ovary  round ligament/cardinal ligament represents the remains of gubernaculums that connects lateral margin of uterus to ovary & contains the ovarian vessels  Supplied by ovarian A. [from abdominal aorta], uterine A.  Drained by ovarian V. w/c ends in IVC on R, and L renal V. on L  Lymphatics drain to paraortic nodes at L1 level.  Nerve supply from aortic plexus w/c accompanies ovarian A. UTERINE TUBE / FALLOPIAN TUBE/ OVIDUCT  Connects uterine cavity to peritoneal cavity  Functions: to convey ovum to uterine cavity, serve as conduit for spermatozoa, provide the appropriate environment for fertilization to occur  Divisions: infundibulum, ampulla [widest], isthmus [narrowest], intramural part  Supplied by uterine and ovarian A., drained by uterine venous plexus  Lymphatics: lumbar nodes  Innervated by ovarian and uterine plexus UTERUS  Organ in w/c the embryo or fetus develops and is nourished until birth  Divisions: fundus, body, cervix  Can be anteverted [angled forward at the junction of cervix and vagina], and anteflexed [angled forward at junction of body and cervix]  Supplied by uterine and ovarian A., drained by uterine venous plexus  Lymphatics: lumbar [fundus], external iliac [body], internal iliac and sacral [cervix]  Innervated by uterovaginal plexus  Supported by: 1. transverse cervical or cardial ligament [Mackenrodt’s] – from cervix to laeral fornix of vagina 2. uterosacral ligament – from lower end of sacrum to cervix & upper end of vagina 3. pubocervical ligament – from posterior surface of pubis to cervix 4. round ligament of uterus – btw angle of uterus, thru inguinal ring & labia majora 5. broad ligament – formed by 2 layers of peritoneum and contains the uterine tube, round ligament of uterus, ovarian ligament, nerves, lymphatics, ovarian and uterine vessels Clinical notes Hysterectomy procedure  In hysterectomy, the ureter may be injured or inadvertently ligated because of the proximity of the ureter to the cervix and to uterine artery. Metastasis & the Round ligament  CA of the fundus of the uterus may metastasize to superficial inguinal nodes along lymphatic vessels that course w/ the round ligament. VAGINA  Female organ for copulation receiving penis during coitus  Serve as excretory duct for products of menstruation  Highly distensible fibromuscular tube  Supplied by uterine A. [superior], middle rectal and internal pudendal A. [middle and inferior], drained by vaginal venous plexus  lymphatics: internal and external [superior], internal iliac [middle], sacral and common iliac [inferior]  innervated by uterovaginal plexus [superior] and pudendal N. [lower]  Supported by: 1. levator ani muscle 2. urogenital diaphragm 3. perineal body 4. transverse, cervical, uterosacral, and pubocervical ligaments Homologues Embryologic remnant Developing gonad Genital tubercle Genital urethral folds Genital swellings Gubernculum Urogenital sinus

Male Testis Glans of penis Penile urethra Scrotum Gubernaculums testis Bulbourethral/Cowper’s Prostate gland Corpus spongiosum

Female Ovary Glans of clitoris Labia minora Labia majora Round ligament of ovary Bartholin’sl glands Skene’s gland [paraurethral] Vestibular bulbs

Name Internal iliac A.

Branches Anterior division: umbilical, obturator, inferior gluteal, internal pudendal, inferior vesical, middle rectal, uterine and vaginal arteries Posterior division: superior gluteal, lateral sacral, iliolumbar A. Umbilical A. Superior vesical A. [3], Artery to ductus deferens Common iliac A. Divides into internal and external iliac A. External iliac A. Inferior epigastric A., deep circumflex iliac, and femoral A. Veins of the pelvis – accompanies similar branches w/ the arteries Lymphatic drainage of pelvis: Internal iliac nodes [Where most vessels drains], Aortic nodes [from ovary and testis], Inferior mesenteric nodes [From rectum] Nerves of pelvis: Sacral plexus Name Sciatic N. Superior gluteal Inferior gluteal Posterior femoral cutaneous N. to obturator internus N. to quadratus femoris Pudendal N.

Features Largest branch, consists of common peroneal and tibial nerves Supplies gluteus medius + minimus, tensor fascia lata, and hip joint Supplies gluteus maximus Supplies buttocks, posterior thigh, popliteal fosa, external genitalia Supplies superior gemellus and obturator internus muscles Supplies inferior gemellus and quadratus femoris Has no branches in the gluteal region

PERINEUM [refer to Netter p. 350-354]  Diamond-shaped area below pelvic diaphragm  Bounded by pubic symphysis [anterior], ischial tuberosities [lateral], and coccyx [posterior], pelvic diaphragm [roof], skin and fascia of perineum [floor] Anal triangle & urogenital triangle Boundaries Urogenital triangle Front Pubic arch Lateral Ischial tuberosities, rami of ischium & pubis Posterior Imaginary line Contents of perineum Anal canal Internal anal sphincter External anal sphincter Ischiorectal / ischioanal fossa Pudendal / ALCOCK’S canal

Anal triangle Imaginary line Ischial tuberosities, sacrotuberous lig. Tip of coccyx

Continues w/ rectum at pelvic diaphragm Controlled reflexly and involuntarily Controlled voluntarily Contains the ischioretal fat pad, pudendal N. and internal pudendal vessels, inferior rectal N. and vessels, and the perineal branch of posterior femoral cutaneous nerve A tunnel in the fascia of obturator internus M. and contains pudendal N. and internal pudendal vessels to the perinum

Clinical notes Internal hemorrhoids  Are painless protrusions of anal canal covered by mucosa. They contain dilated veins of the internal rectal venous plexus. External hemorrhoids  Are painful enlargements covered by skin that contains dilated veins of the external rectal venous plexus. Differences between internal and external anal sphincter Characteristic Internal anal sphincter Epithelium Simple columnar Pain Insensitive Hemorrhoids Internal Lymphatics Pelvic nodes Anal columns Present Innervation Inferior hypogastric plexus

External anal sphincter Stratified squamous Sensitive External Superior inguinal nodes Absent Inferior rectal N.

Clinical notes Disorders of micturition  A spinal, automatic or spastic bladder may result from lesions to spinal cord above sacral levels. In these pxs, parasympathetic neurons that innervate detrusor muscle are not inhibited effectively when bladder is stretched during filling. The detrusor contracts in response to a minimum amount of stretch causing frequent emptying.  An atonic bladder may result from lesions to sacral spinal cord or to the roots of sacral spinal nerves in cauda equina. These lesions disrupt the neural components of vesical reflex. Bladder fills to capacity but urine dribbles thru urethra continuously because detrusor fails to contract and empy the bladder, and the voluntary urethral sphincter may be wekened. Pxs tend to retain a considerabe volume of urine w/ high infection risk and pass urine only as a result of overflow incontinence. Injury to cavernous sinus  In surgical procedures involving prostate, the cavernous nerves may be lesioned. This nerves course lateral to prostate before passing thru urogenital hiatus to enter the perineum.  This pxs may have impotence [inability to obtain erection].

Arteries of the pelvis [refer to Netter p. 371]

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UROGENITAL TRIANGLE [refer to Netter p. 355, 367] Urogenital diaphragm Penetrated by membranous urethra in M, and by membranous urethra and vagina in F Deep perineal pouch Deep transverse perineal M. Supports the pelvic viscera, innervated by deep perineal N. Sphincter urethrae muscle Compresses membranous urethra, supplied by deep perieal N. Superficial perineal pouch Superf transverse perineal M. Stabilize perineal body, iinervated by deep perineal N. Ischiocavernous muscle Help maintain erection, supplied by deep perineal N. Bulbospongiousus muscle Maintain erection, supplied by deep perineal N. Perineal body Aka as central tendon of perineum, it support s pelvic organs Nerve supply of perineum: Pudendal nerve [branches: inferior rectal N., perineal N., dorsal nerve of penis or clitoris] Clinical notes Pudendal nerve block  This may be performed to suppress labor pain by anesthesizing pudendal nerve as it crosses the iliac spine. Blood vessels to perineum Internal pudendal A. principal blood supply to perineum; branches: inferior rectal A., perineal A., artery to bulb of penis or clitoris, deep artery of penis or clitoris, and dorsal artery of penis or clitoris Perineal A. Enters superficial perineal pouch and gives rise to tansverse perineal A. and the posterior scrotal or labial A. External pudendal V. Receives the superficial dorsal vein of penis or clitoris and ends in great saphenous V. Deep dorsal vein of Drains into prostatic venous plexus [M], or vesical venous plexus [F] penis or clitoris Lymphatic drainage of perineum Superficial inguinal nodes Drains lower part of anal canal Internal iliac nodes Drains deep perineal space, membranous urethra, vagina . RAPID REVIEW  Divisions of pelvis: o Greater/major/false pelvis  Behind: lumbar vertebra  Lateral: iliac fossa and iliacus mucle  Front: lower part of abdominal wall o Lesser/minor/true pelvis Boundaries Pelvic inlet Pelvic outlet Lateral Ileopectineal line Ischial tuberosiities Posterior Sacral promontory Coccyx Anterior Pubic symphysis Pubic arch           

Bladder usually enter the greater pelvis by 6 years Holds kidney in position: fibrous capsule, perirenal fat and renal fascia 70 million sperms is required to impregnate a female Conveys sperm from epididymis to urethra: ductus deferens Largest accessory gland in males: prostate, in females: paraurethral glands MC site of obstruction to urethra: middle prostate lobe Usually lacerated during sex: fornix of the vagina Skeene’s gland – secretes mucuc for acidity of vagina Bartholin’s gland – secretes lubricant during sexual act for penis to slide thru Not supplied by internal iliac artery in females: ovary Main nerve in the perineum and chief sensory nerve of external genitalia: pudendal nerve

 o o o  o o o  o o o o o o

Boundaries of anal triangle: Behind: tip of coccyx Side: ischial tuberosity, sacrotuberous ligament, ischiorectal fossa Midline: anus Boundaries of anal canal: Posterior: anococygeal body Lateral: ischiorectal fossa Anterior: perineal body, urogenital diaphragm, membranous urethra, bulb of penis, lower vagina Boundaries of ischiorectal/ischioanal canal or fossa Lateral: ischium, obturator internus Medial: anal canal Posterior: sacrotuberous ligament, gluteus maximus Anterior: external urethra sphincter, deep transverse perineal muscle Superior: pelvic diaphragm Inferior: skin

      

Boundaries of urogenital triangle: o Anterior: pubic arch o Lateral: ischial tuberosity Marks lower end of GIT: anocutaneous line Line between upper and lower anal: dentate line Non-muscular segment of anal canal between internal and external anal sphincter: Hilton’s white line Area of infection during habitual constipation: Crypts of morgagni Fibrous tissue w/c separates posterior surface of urinary bladder and prostate gland from anterior rectal wall: Denonvillier’s fascia secretes mucus that maintains acidity of penis: Gland of Tyson’s

RECTAL EXAM: screening procedure of choice in:  Prostate CA  Colorectal CA CHAPTER 7– BACK VERTEBRAL COLUMN  Consists of 32-34 individual vertebrae and their intervertebral disks  It protects he spinal cord and supports the weight of the head and trunk Type Features Cervical vertebrae [7] Atlas [atypical C1], axis [atypical C2], C7 w/ vertebral prominens Thoracic vertebrae [12] Atypical are the T1, T10, 11, and 12 Lumbar vertebrae [5] Massive, w/ kidney-shaped body Sacrum Fusion of 5 sacral vertebrae Coccyx Triangular bone from 4 rudimentary coccygeal vertebrae Clinical notes Spina bifida  Results when laminae fail to fuse to form a spinous process and is most commonly seen at lower lumbar or sacral vertebral levels.  In spina bifida occulta, 1 or more spinous processe fail to form at lumbar or sacral levels. This is asymptomatic and may be marked by a tuff of hair in skin over the defect.  In spina bifida cystica, a cyst protrudes thru the defect in vertebral arch. These conditions can be diagnosed in utero based on elevated levels of AFP after amniocentesis and by UTZ. This may result in hydrocephalus and neurological deficits.  In spina bifida cystica w/ meningocele, the cyst is lined by meninges and contains CSF.  In spina bifida cystica w/ meningomyelocele, the lumbosacral spinal cord is also in the cyst. Displacement of the cord stretches the lumbosacral spinal nerves and results in bladder, bowel, or limb weakness.  In spina bifida w/ myeloschisis or rachischisis, the caudal end of neural tube fails to close in the dorsal midline and is exposed on back surface. Joints between vertebrae Name Intervertebral disks Facet /zygapophyseal joints

Features Fibrocartilaginous joint between adjacent vertebrae, functions as shock absorber when distorted by compression, consists of annulus fibrosus and nucleus pulposus [remnant of notochord] Synovial joints between superior and inferior articular facets

Curvatures of the vertebral column A. Normal curvatures Primary curvatures Exits before birth, C-shaped and is concave anteriorly, retained in the thoracic and sacral regions of the adult Secondary Develops after birth, concave posteriorly, and is retained curvatures in cervical and lumbar vertebra B. Abnormal curvatures Lordosis Convex anteriorly, seen in pregnant women KyPOSis Convex POSteriorly [MC due to postural], seen in old age Scoliosis Lateral curvature of the spine Deep muscles of the back [refer to Netter p. 160] Name Innervation Splenius cervicis & capitis Dorsal primary rami of spinal nerves Erector spinae Iliocosalis Dorsal primary rami of spinal nerves Spinalis Dorsal primary rami of spinal nerves Longissimus Dorsal primary rami of spinal nerves Transversospinal muscles Semispinalis Dorsal primary rami of spinal nerves Mutifidus Dorsal primary rami of spinal nerves Roatores Dorsal primary rami of spinal nerves SUBOCCIPITAL REGION

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 Lies deep to semispinalis capitis muscle in the upper part of neck  Include the suboccipital muscles, suboccipital N., greater occipital N., 3rd occipital N., and the vertebral A.  Muscles of the suboccipital region [refer to Netter p. 162] Name Innervation Action Rectus capitis posterior major Suboccipital N Extends head and rotates to same side Rectus capitis posterior minor Suboccipital N Extension of head Obliquus capitis inferior Suboccipital N Rotation of head to same side Obliquus capitis superior Suboccipital N Extension and lateral flexion of head  Vessels and nerves in suboccipital region Suboccipital N. Supplies the suboccipital muscles Vertebral A. From subclavian A. to supply post. atlantooccipital membrane Greater occipital N Supplies cutaneous innervation to scalp 3rd occipital N. Supplies cutaneous innervation to scalp  o o o o

Boundaries of suboccipital triangle: Medially: rectus capitis posterior major Laterally: obliquus capitis superior Inferiorly: obliquus capitis inferior Contents: Vertebral artery and suboccpital nerve

Other features of the back Boundaries Triangle of auscultation in the back Medial Trapezius, lateral border Lateral Scapula, medial border Inferiorly

Latissimus dorsi, upper border

Lumbar triangle: Latissimus dorsi, medial border External abdominal oblique, posterior border iliac crest, upper border

Innervation of the back  Both the intrinsic muscles of the back and the overlying skin ae supplied in a segmental pattern by dorsal primary rami of spinal nerves [w/ medial and lateral branches] MENINGES Dura mater Arachnoid Pia mater

Fuses w/ inside of the skull at foramen magnum, surrounded by epidural space Intermediate layer, ends inferiorly at the level of 2nd sacral vertebra Extends from lower end of spinal cord as the filum terminale

Other features of the meninges Epidural space Contains fat and internal vertebral venous plexus Subdural space Only a potential space, may collect leaking blood Subarachnoid space Contains CSF, and cauda equine below the end of spinal cord Denticulate ligament Extension of pia mater on lateral sides of spinal cord Filum terminale Extension of pia mater from conus medullaris Batson’s venous Provides pathway for dispersion of malignant tumor cells from the plexus pelvic, abdominal and thoracic vertebrae, spinal cord and brain Clinical notes Lumbar puncture  Allows removal of CSF from lumbar cistern of the subarachnoid space  Involves insertion of a needle in midline between 3rd and 4th or 4th and 5th lumbar vertebrae  Penetrates: skin, fascia, supraspinous ligament, interspinous ligament, ligamentum flavum, epidural space, dura, arachnoid, subarachnoid  In a lumbar puncture off the midline, needle will traverse a ligamentum flavum instead of supraspinous and interspinous ligaments and intralaminar space. Radiculopathies  Results from compression of roots of spinal nerves in intervertebral foramina or in vertebral canal.  S/Sx: pain and paresthesia in the form of numbness or tingling in dermatomes supplied by the compressed sensory roots. Pain may radiate over dermatomal distribution of the affected sensory roots. Pxs may also have weakness of skeletal muscles in myotomes supplied by compressed motor roots.  Osteoarthritis is an inflammation resulting in additional bone growth by osteophytes at facet joints  Spondylitis is an inflammation that results in additional bone growth by osteophytes at margins of vertebral bodies. Pxs may exhibit ankylosis [joint stiffening] and a “bamboo spine”.  Spondylosis involves degenerative changes in intervertebral disks w/c are usually combined w/ additional bone growth by osteophytes at margins of vertebral bodies.  A herniated disk exists when nucleus pulposus protrudes at posterolteral part of an annulus fibrosus resulting in compression of roots of lower cervical or lower lumbar spinal nerves. The compressed roots are those of the more inferior spinal nerve [ex. Herniations at C5-6 disk compress C6 roots, herniations at L4-5 disk compress L5 roots]. Whiplash  Causes cervical vertebrae to be strongly extended and then strongly flexed and may result in anterior dislocation of facet joints.

Herniated nucleus pulposus  This MC occurs btw C6 and 7, w/c compresses C7 spinal nerve or less commonly btw C7T1 w/c compresses C8 spinal nerve.  C7 compression may result in referred pain in neck and shoulder w/ pain and paresthesia in index and middle fingers.  C8 compression may result in pain in the neck and shoulder and pain and paresthesia in the ring and little fingers.  A cervical rib may emerge from costal process of C7. The T1 spinal nerve and subclavian A. may be compressed as they course superior to cervical rib instead of superior to the 1 st thoracic rib. Pxs may present w/ diminished radial pulse and pain and paresthesia in medial forearm. Horner’s syndrome may also be present. Spondylosis & spondylolisthesis  In spondylolysis, there is a defect or fracture of the isthmus, w/ no anterior displacement of vertebral body.  In spondylolisthesis, a uni/bilateral defect or fracture of the isthmus is accompanied by anterior displacement of vertebral body. MC site is btw L5 and sacrum and may stretch roots of lumbosacral spinal nerves in cauda equina. Pxs may have bilateral lower back pain that radiates into both lower limbs and weakness in leg muscles.  Spinal stenosis or narrowing of vertebral canal can be caused by spondylosis [in w/c degenerative changes occur in L4 or L5 interverebral disks or osteoarthritis [at facet joints of the vessels].  L5 compression may result in sciatica, characterized by pain that radiates from the back thru posterior thigh into leg and foot, combined w/ pain and paresthesia in anterolateral leg and dorsum of foot. There may be weakness in extension of great toe [extensor hallucis longus] and weakness in dorsiflexion [tibialis anterior].  S1 compression may also result in sciatica, combined w/ pain and paresthesia in posterolateral leg, heel, and lateral side of foot. There may be wekness in flexion of the leg at knee [hamstrings], weakness in plantar flexion [gastrocnemius and soleus] and a diminished Achilles tendon reflex. Epidural or caudal block  Is performed by administering anesthetic thru sacral hiatus w/c diffuses thru meninges and anesthesizes the roots of sacral and coccygeal spinal nerves in cauda equina. SPINAL CORD  Begins at foramen magnum where it is continuous w/ medulla of brain stem  Ends at level of lower border of L1 in adult  Receives blood from single anterior spinal A. and paired posterior spinal A., and radicular A.  Veins drain into internal vertebral venous plexus. Spinal nerves  31 pairs of segmentally aanged nerves: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal  Union of dorsal and ventral root at intervertebral foramen  Are mixed nerves containing all of the general functional components Arterial supply of the back Level Arterial supply Cervical ganglion Occipital, vertebral, deep and ascending cervical arteries Thoracic Posterior intercostal A. Lumbar Subcostal and lumbar A. Sacral Iliolumbar and lateral sacral A. Venous drainage of the back: external and internal vertebral venous plexus and basivertebral veins Lymphatic drainage of the back: Name Drainage Superficial LN Above iliac crest: axillary nodes; Below iliac crest: superficial inguinal nodes Deep LN Deep cervical, posterior mediastinal, lateral aortic, and sacral nodes Nerve supply of the back: frm posterior rami of C1, 6, 7 and 8, also of L4-5 spinal nerves. CHAPTER 8 – HEAD & NECK Muscles of the anterior neck Name Innervation Trapezius Spinal accessory Sternocleidomastoid Spinal accessory Infrahyoid muscles Sternohyoid Ansa cervicalis Sternothyroid Ansa cervicalis Thyrohyoid Hypoglossal N. Omohyoid Ansa cervicalis Suprahyoid muscles Stylohyoid Facial N. Digastric Ant: Mylohyoid Post: facial N. Mylohyoid Mylohyoid N. Geniohyoid Hypoglossal N.

Action Elevates and rotates scapula Flex head + neck, rotates face opposite sd\ide Depresses hyoid bone and larynx Depresses hyoid bone and larynx Depresses hyoid bone and elevates larynx Depresses hyoid bone Eleates hyoid bone Elevates hyoid bone and tongue, depresses mandible Elevates floor of mouth and hyoid bone Elevates hyoid bone and tongue

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Muscles of the posterior neck Name Innervation Lateral group Scalenus anterior Cervical spinal N. Scalenus medius Cervical spinal N. Scalenus posterior Cervical spinal N. Scalenus minimus Cervical spinal N. Levator scapulae Dorsal scapular N. Prevertebral/Anterior Longus capitis Cervical nerves Longus colli Cervical nerves Rectus capitis anterior Cervical plexus Rectus capitis lateralis Cervical plexus  o o o o o o  o o o  o o o o o  o o o  o o o  o o o  o o o o o o o  o o o o  o o o o

Action Laterally flex the neck, elevates 1st rib Laterally flex neck, elevates 1st rib Laterally flex neck elevates 2nd rib Laterally flex neck, elevates 1st rib Elevates scapula Flexes head Flexes and rotates head and neck Flexes head Laterally flex head

Boundaries of the anterior triangle of the neck: Base: mandible Apex: jugular notch Lateral: sternocleidomastoid Anterior: median line of neck Posterior: anterior border of sternocleidomastoid Roof: subcutaneous tissue, platysma Boundaries of submandibular trangle: Roof: mandible and digastric Floor: mylohyoid, hyoglossus Contents: submandibular gland, facial vein and artery, submandibular LN Boundaries of the submental triangle: Inferior: hyoid bone Lateral: digastric Roof: hyoid bone, digastric, mandibular symphysis Florr: mylohyoid Contents: submental LN, beginning of anterior jugular veins Boundaries of the thyroid triangle: Superior: superior omohyoid Middle: median raphe Inferior: Boundaries of the muscular triangle: Roof: sternocleidomastoid [anterior border], omohyoid, anterior midline of neck Floor: sternothyroid, sternohyoid Contents: anterior juguylar vein, sternohyoid, sternothyroid, thyroid and parathyroid glands Boundaries of digastric triangle: Lateral: mandibular margin Middle: digastric, superior belly Inferior: digastric, inferior belly Boundaries of the posterior triangle of the neck: Lateral: trapezius Medial: sternocleidomastoid Apex: mastoid bone Base: clavicle Anterior: sternocleidomastoid, posterior border Posterior: trapezius, anterior border Contents: accessory N., roots of brachial plexus, subclavian A., suprascapular N., supraclavicular N., dorsal scapular and long thoracic N., nerves to levator scapulae, transverse cervical and suprascapular arteries Boundaries of occipital triangle: Lateral: trapezius Medial: sternocleidomastoid, upper part Posterior: omohyoid, inferior border Contents: occipital nerve, cervical plexus, splenius Boundaries of supraclavicular or subclavian triangle: Anterior: sternocleidomastoid Superior: omohyoid Inferior: clavicle Contents: subclavian artery and vein, suprascapular artery, supraclavicular LN

Carotid sheath  Formed by pretracheal, prevertebral and investing layers of deep cervical fascia

 Contents: common, external & internal carotid A., internal jugular vein and vagus N.  o o o o o

Boundaries of the carotid triangle: Superior: digastric, posterior belly Posterior: sternocleidomastoid Inferior: superior omohyoid Roof: sternocleidomastoid, omohyoid, digastric Floor: middle and inferior pharyngeal constrictor muscles, thyrohyoid

o Contents: internal jugular vein, common carotid artery, internal and external carotid artery, superior thyroid, lingual and facial artery, vagus and hypoglossal nerves, caroitid sheath, larynx, pharynx, deep cervical lymph node, and cervical plexus Clinical notes Baroreceptor & chemoreceptor reflexes  Baroreceptor reflex maintains BP in response to changes in posture. Disrupted barorereceptor reflex results in orthostatic hypotension, a decrease in BP when px assumes an upright position.  Chemoreceptor reflex maintains blood gases by adjusting respiration, cardiac output, and peripheral BP. A decrease in oxygen tension [PO2] and increase in CO2 tension [PCO2], result in an increase respiration, HR, and peripheral BP. Arteries of the Neck Name Subclavian A. Vertebral A. Thyrocervical trunk Inferior thyroid A. Transverse cervical A. Suprascapular A. Internal thoracic A. Costocervical trunk Dorsal scapular A. Common carotid A. Internal carotid A. External carotid A. Superior thyroid A. Lingual A. Facial A. Occipital A. Posterior auricular A. Ascending pharyngeal A. Maxillary A. Superficial temporal A.

Branches Vertebral, A. internal thoracic A., thyrocervical trunk, costocervical trunk, and dorsal scapular A. Radicular arteries and muscular branches Inferior thyroid A., transverse cervical A., suprascapular A. Ascending cervical A. and inferior laryngeal A. W/ superficial and deep branches None joins the suprascapular N. Superior epigastric and musculophrenic A. Deep cervical, and superior intercostals A. Accompanies dorsal scapular N. on deep surface of rhomboids Internal and external carotid A. None in neck [ophthalmic, posterior communicating, middle cerebral A.] Superior thyroid, lingual, facial, occipital, posterior auricular, ascending pharyngeal, maxillary, and superficial temporal A. Superior laryngeal A. Suprahyoid branch, dorsal lingual, deep lingual , and sublingual A. Neck: ascending palatine, tonsllar, glandular, and submental A. Face: inferior and superior labial, lateral nasal and angular A. Sternomastoid, meningeal, descending and occipital branches Auricular, occipital and stylomasoid branches Pharyngeal, meningeal, palatine branches, inferior tympanic A. Deep auricular, anterior tympanic, middle meningeal, inferior alveolar, posterior superior alveolar, infraorbital, sphenopalatine, descending palatine, pharyngeal A. and A. to pterygoid canal Transverse fascial A.

Veins of the head face and neck Name Features Fascial vein Provides a danger area of face due to potential spread of infection Retromandibular v. Union of maxillary and superficial temporal veins External jugular V. Union of posterior auricular V. and post. div. of retromandibular V. Anterior jugular V. Connected to jugular venous arch Internal jugular V. Continuation of sigmoid venous sinus, receives facial, lingual, pharyngeal, and middle thyroid veins Subclavian V. Continuation of axillary V. Lymphatic drainage of head and neck Name of lymph node Drainage Occipital nodes Back of scalp Mastoid / post. auricular Back of scalp, auricle of ear, external auditory meatus Parotid nodes Anterior scalp, external and middle ear, paotid gland Buccal / facial nodes Eyelids, conjunctiva, nose, cheek Submandibular nodes Nose, lips, gums, cheeks, tongue Submental nodes Tip of tongue, floor of mouth, lower lip and chin Superficial cervical nodes Lower parotid region, ngle of jaw, auricle of ear Anterior cervical nodes Skin and subcutaneous tissue on anterior neck Retropharyngeal nodes Nasopharyx and auditory tube Tracheal nodes Trachea and thyroid gland Jugulodigastric node Posterior 3rd of tongue and palatine tonsil Juguloomohyoid node Anterior 2/3 of tongue Nerves of the neck Name of nerve Cervical plexus Lesser occipital N. Great auricular N. Transverse cervical N. Supraclavicular N. Phrenic N. Ansa cervicalis

Features Lesser occipital. great auricular, transverse cervical, supraclavicular N. Supplies skin of neck and scalp behind the ear To auricle, parotid gland, and angle of the jaw To skin of anterior neck To skin over clavicle and shoulder To pericardium, pleura, and peritoneal coverings To infrahyoid muscles, EXCEPT for THYROHYOID muscle

Brachial plexus Dorsal scapular N.

To rhomboid major and minor

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Long thoracic N. Suprascapular N. N. to subclavius Cranial nerves in neck Hypoglossal N. Accessory N. Vagus N. Superior cervical ganglion Middle cervical ganglion Inferior cervical ganglion Ansa subclavia

To serratus anterior To supraspinatus and infraspinatus To subclavius muscle Gives superior root of ansa cervicalis and N. to thyrohyoid M. Gives a cranial and spinal portion Gives a cardiac, meningeal, auricular, pharyngeal brnches and superior laryngeal and recurrent laryngeal N., Gives rami communicantes, superior cervical sympathetic cardiac N. internal and external carotid N., communicating Gives rise to gray rami comunicantes, middle cervical sympathetic cardiac N.and branches to perivascular plexus Gves rise to gray rami communicantes, inferior cervical sympathetic cardiac N. and branches to priarterial plexus Connects inferior cervical ganglion to vertebral ganglion or the middle cervical ganglion

Clinical notes Excessive vasoconstriction  A stellate ganglion block may be performed in pxs who exhibit excessive vasoconstriction or sweating in upper limb. Horner’s syndrome  Caused by a lesion on cervical part of sympathetic trunk or superior cervical ganglion. Pxs have anhydrosis, ptosis and miosis. Accesory nerve lesions  Lesion at posterior triangle may result in weakness of trapezius muscles. Px may have difficulty elevating scapula [shrugging of shoulder] and difficulty in laterally rotating scapula during abduction of the arm.  Lesions inferior to jugular foramen may also result in weakness of sternocleidomastoid. Pxs may have decreased ability to turn chin to side opposite the lesioned nerve. Vagus nerve lesions  Complete lesions of vagus N. commonly result in weakness of palate, pharyngeal, and aryngeal muscles.  Weakness of levator veli palatini may result in drooping of palate on side of the injured nerve and a deviation of uvula to side opposite the lesioned nerve. Pxs may also experience nasal speech and nasal regurgitation of liquids during swallowing.  Weakness of pharyngeal constrictors may result in dysphagia [difficulty in swallowing].  Lesions of vagus nerve that includes the laryngeal nerves may result in weakness of all laryngeal muscles on the affected side. Vocal cord may assume a fixed position midway btw abduction and adduction, resulting in speech that is hoarse and weak. Lesions of the pharyngeal branches & laryngeal N. may also result in loss of motor limb of GAG reflex and cough reflex respectively. VISCERA OF THE NECK  3 layers of cervical viscera [superior and deep] Endocrine layer Thyroid and parathyroid Respiratory layer Larynx and trachea Alimentary layer Pharynx and esophagus

 Lymph drainage: pratracheal nodes and inferior cervical nodes THYROID GLAND  An endocrine gland that secretes T3 and T4 w/c regulates the metabolic rate of body tissues, and thyrocalcitonin w/c is concerned w/ regulation of calcium catabolism in body tissues  Consists of R and L lobes joined by isthmus  Surrounded by fibrous capsule derived from pretracheal fascia Lobes Extend inferiorly to level of 5th or 6th tracheal ring, covered by sternothyroid and sternocleidomastoid muscles Isthmus Lies over the 2nd and 3rd tracheal rings, vulnerable to injury Pyramidal lobe May be attached to hyoid bone by levator glandulae thyroideae, drained by superior, middle and inferior thyroid veins, supplied by superior and inferior thyroid A. and sometimes thyrpidea ima A. 

Veins of thyroid gland Superior thyroid V. Drains into internal jugular V. Middle thyroid V. Drains into internal jugular V. Inferior thyroid V. Drains into L brachiocephalic V.

 Blood supply of thyroid gland Superior thyroid From 1st branch of external carotid A., w/ ant and post branches A. Inferior thyroid A. From thyrocervical trunk, it is intimately related to recurrent laryngeal N. w/c is vulnerable in surgery of thyroid gland Thyroid ima A. Inconstant branch of the brachiocephalic trunk or aortic arch, it lies anterior to trachea thus is vulnerable to injury during thyroid surgery or surgical tracheostomy

PARATHYROID GLAND  Small endocrine glands [4] w/c lie on or embedded in posterior aspect of thyroid gland  Secretes PTH essential for regulation of calcium metabolism in body tissues  Arise as diverticulae of the 3rd and 4th branchial pouches  Blood supply of parathyroid gland Inferior thyroid A. Main supply Others Superior thyroid, thyroidea ima, laryngeal, tracheal and esophageal arteries  Veinous drainage to parathyroid V. [from anterior thyroid venous plexus]  Lymphatics: deep cervical LN and paratracheal LN  Innervated by thyroid branch of cervical sympathetic ganglia TRACHEA  Begins in the neck at the lower border of cricoid cartilage as the inferior continuation of larynx and terminates by bifurcating at level of the sternal angle  10-12 cm long and 1.5-2 cm in diameter  w/ series of tracheal rings completed posteriorly by trachealis muscle ESOPHAGUS  begins at the level of cricoid cartilage as continuation of the pharynx  Innervated by SVE fibers from recurrent laryngeal N.  Supplied by branches of the inferior thyoid A. CHAPTER 9 - HEAD BONES OF THE SKULL Cranial bones Name Features Parietal Paired bones that articulate w/ each other at midline sagittal suture Frontal Unpaired bone that forms the forehead and roof of orbit, it has squamous, orbital bone and nasal portions, it contains the supraorbital foramen [for orbital A. and N.], supratrochlear notch [for supratrochlear A. and N.] Occipital Unpaired bone that forms base of the skull Temporal Paired bones Sphenoid Unpaired bone Ethmoid Unpaired cube-shaped bone Sutures and landmarks of cranium [refer to Netter atlas p. 4] Name Features Coronal suture Articulation btw frontal and paired parietal bones Sagittal suture Articulation btw paired parietal bones Lambdoid suture Articulation btw paired parietal bones and occipital bones Squamous suture Articulation btw parietal bone and squamous part of temporal bone Bregma Point at w/c sagittal and coronal sutures meet Lambda Point at w/c sagittal and lambdoid sutures meet Vertex Highest point of the skull near midpoint of sagittal suture Nasion Point at w/c frontal and nasal bones meet Pterion Temporal region where frontal and parietal bones meet the greater wing of sphenoid bone and the squamous part of temporal bone Inion Highest point of external occipital protuberance Glabella Region above nasion btw paired superciliary arches Anterior fontanelle At area of bregma, closes a 18 mos, Posterior fontanelle At area of lambda, closes by end of 1st year Clinical notes SKULL FRACTURE AT PTERION  A lateral skull fracture at pterion [thinnest part of calvaria], may lacerate the middle meningeal A. and cause epidural hematoma.  The epidural hemorrhage forms a biconvex lens-shaped hematoma btw skull and periosteal dura, w/c does not pass sutures.  An epidural hematoma may compress lateral part of a cerebral hemisphere and result in herniation of medial temporal lobe thru tentorial notch of dura. The herniated temporal lobe may compress the brainstem.  Px may have an initial lucid asymptomatic interval followed by weakness of limb muscles, a dilated pupil resulting from compression of occulomotor nerve [CN 3], and deterioration of cardiorespiratory functions. Facial bones Name Maxillae Zygomatic bone Nasal bones Lacrimal bone Palatine bones

Features Pair of bones that fuse to form upper jaw Paired bones that forms the prominence of cheek Paired bones that fuse to form the central portion of zygomatic arch Paired bone that contributes to anterior part of medial wall of orbit L-shaped bones consists of horizontal and perpendicular plates

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Vomer Inferior nasal cioncha Mandible

Unpaired midline bone that forms the posterior & inferior nasal septum Attached to lateral wall of nasal cavity Bone of the lower jaw, consists of a body and paired rami

CRANIAL CAVITY Circle of Willis  Completed by an anterior communicating A. w/c connects anterior cerebral A. and a pair of posterior communicating A. w/c connects the internal carotid A. w/ posterior cerebral A.  MC site of aneurysm – anterior communicating artery  Left and right artery – basilar artery [brainstem] Clinical notes Berry aneurysms  Are saccular dilatations of walls of arteries w/c MC occur in anterior part of the circle of Willis at branch points of anterior and posterior communicating A., or middle cerebral A. Blood from ruptured aneurysm may accumulate in subarachnoid space and causes subarachnoid hematoma.  Pxs may experience an acute explosive “worst headache of my life” caused by blood leaking from aneurysm, w/c irritates the meninges. Pxs may also have stiff nek resulting from irritation of spinal dura.  Occulomotor N. [CN 3] may be compressed by an aneurysm at junction of posterior communicating A. and internal carotid A. or posterior cerebral A. pxs may initially have a dilated or a “blown” pupil. Major apertures of the skull Aperture Bone Cribriform plate Ethmoid Optic canal Sphenoid Superior orbital fissure Sphenoid Foramen rotundum Foramen OVALE

Sphenoid Sphenoid

Foramen spinosum Innominate foramen Foramen lacerum

Sphenoid Sphenoid Btw sphenoid and temporal Sphenoid Temporal Temporal

Lacrimal foramen Carotid canal Internal auditory meatus Stylomastoid foramen Jugular foramen

Temporal Btw occipital and temporal

Foramen magnum

Occipital

Hypoglossal canal

Occipital

Traversed by Olfactory N. [filia] Optic N., ophthalmic A. Occulomotor, trochlear, ophthalmic and abducens Nerves, opthalmic V. Maxillary N. Mandibular nerve, Accessory meningeal nerve, Lesser petrosal nerve, Emissary veins [MALE] middle meningeal A., meningeal br. of mandibular N. Lesser petrosal N. Internal carotid A., deep petrosal and greater petrosal N., origin of thenerve of the pterygoid canal Communicating br. btw middle meningeal + lacrimal A. Internal carotid A., periarterial sympathetic plexus Facial N., nervus intermedius, vestibulocochlear N., labyrinthine A. Facial N., stylomastoid A. Glossopharyngeal, vagus, and accessory N., internal jugular V., inferior petrosal sinus, posterior meningeal Arteries and nerves Brainstem, vertebral Arteies and veins, spinal part of accessory N., spinal A. Hypoglossal N., meningeal br. of cervical spinal Nerves

Clinical notes Jugular foramen sndrome

 Lesions of glossopharyngeal N. may occur in conjunction w/ vagus N. and accessory N. in jugular foramen syndrome. Sx: loss of GAG reflex

 Lingual branch of CN IX [glossopharyngeal N.] may be lesioned as it traverses the floor of tonsilar fossa during tonsillectomy procedures. This results in loss of sensation from posterior 1/3 of the tongue. SCALP Skin Connective tissue Aponeurosis Loose connective tse Pericranium

Relatively thick w/ abundant hairs Between skin and galea aponeurotica, w/ nerves and vessels Is the membranous galea aponeurotica w/c connects frontalis and occipitalis components of occipitofrontalis M., in gaping wounds Is the plane of separation for subdural hematoma & scalping injuries, allows spread of infection to galea aponeurotica. Most dangerous area [emissary vessels are located] Periosteum covering the outer surface of skull

Muscles of the Face and Scalp / Muscles of Facial expression Name Features Orbicularis oculi Corugator supercilli Procerus Nasalis Depressor septi

Sphincter of the eye Concern Protects against bright sunlight, wrinkles Depresses skin btw eyebrows Depresses nasal septum

Innervatio n Facial N. Facial N. Facial N. Facial N. Facil N.

Orbicularis oris Depressor anguli oris Depressor labii inferioris Leavtor labii superioris Levator labii superioris alaque nasi Mentalis Risorius Zygomaticus major Zygomaticus minor Buccinator Auricularis Occipitofrontalis Platysma Nerves of face and scalp Name Origin Facial N. Stylomastoid foramen Trigeminal N. Ophthalmic N. Maxillary N. Mandibiular N. Cervical spinal N.

Cavenous sinus F rotondum F ovale

Sphincter of the mouth Frowning Impatience Pulls upper lip superiorly Above action + dilates nostrils Doubt Grinning or sardonic grim Smiling or laughing Sadness, lonely Compress cheeks, aids in mastication, sucking, whistling, “trumpeter’s muscle” Auricular movement Scalp movement, wrinkles scalp Grimace, tension, stress

Facial N. Facial N. Facial N. Facial N. Facial N. Facial N. Facial N. Facial N. Facial N. Facial N. Facial N. Facial N. Facial N.

Branches Temporal, Zygomatic, Buccal, Mandibular, and Cervical N. [Ten Zebras Bought My Car]. It also gives rise to posterior auricular N. and Neves to stylohyoid and posterior digastric Ophthalmic, maxillary, mandibular N. Supraorbital, supra/infratrochlear, lacrimal, ext. nasal Infraorbital, zygomaticofacial, zygomaticotemporal N. Auriculotemporal, buccal, mental nerves Great auricular, lesser and greater occipital nerves

Clinical notes Bell’s palsy  Idiopathic unilateral paralysis of facial muscles due to facial N. lesion  Sudden onset [w/in 24 H], and transient w/ recovery in few months  Characterized by: drooping corner of mouth, inability to smile, whistle or blow, drooping upper eyelid and an everted lower lid, inability to blink or close the eyes Blood vessels of face and scalp Name Branches Superficial temporal A. Transverse facial A., Maxillary A. Mental, buccal, and infraorbital A. Facial A. Inferior labial and superior labial A., lateral nasal, and angular A. Occipital A. None, distributed w/ greater occipital N. to posterior scalp Posterior auricular A. Auricular and occipital branches Ophthalmic A. Supraorbital, supratrochlear, lacrimal and dorsal nasal A. BRAIN Development of brain & spinal cord 1◦ brain vesicles 2◦ brain vesicles Prosencephalon Telencephalon [lateral ventricles] Diencephalons [3rd ventricle] Mesencephalon Mesencephalon [cerebral aqueduct or ITER] Rhombencephalon Metencephalon Myelencephalon

Mature brain Cerebral hemispheres Thalamus, hypo/epi/subthalamus, Midbrain Pons & cerebellum Medulla oblongata

PAROTID GLAND  Largest, lies below zygomatic arch and external auditory meatus  Overlies massetr M. and ramus of mandible anteriorly, sternocleidomastoid posteriorly  Separated from submndibular gland by stylomandibulr ligament  Structures w/in parotid gland: Facial N., Retromandibular V., External carotid A. & parotd LN  Parotid duct / STENSEN’S duct – passes over masseter muscle and opens into oral cavity opposite the upper 2nd molar  Supplied by superficial temporal and external carotid A., drained by retromandibular V.  Innervated by: parasympathetic N. [secretomotor] and sympathetic [vasomotor] nerves  Lymphatics: parotid nodes [to superficial and deep cervical LN] Clinical notes Parotid gland tumor  May compress muscular branches of facial N. and cause weakness of muscles of facial expression on side of the tumor. SUBMANDIBULAR GLAND  Found in submandibular and digastric triangle  Submandibular / WHARTON’S duct – related closely to lingual N.  Lies between mandible and mylohyoid muscle  Supplied by submental A. and veins  Innervated by submandibular ganglion

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 Lymphatics: deep cervical LN [part of jugulo-omohyoid node] Boundaries of the temporal and infratemporal fossae Features Temporal fossa Superiorly Inferior temporal line Anteriorly Frontal part of zygomatic bone Inferiorly Zygomatic arch Posteriorly Inferior temporal line Contents Temporalis M., deep temporal N. and A., zygomaticotemporal N. Muscles of mastication Name Innervation Temporalis Deep temporal N. Masseter Masseteric N. Lateral pterygoid N. to lat. pterygoid Medial pterygoid N. to medial pterygoid

Infratemporal fossa Greater wing of sphenoid Maxilla Continuous to neck Temporomndibulr jt, styloid process Mandibular N., maxillary A., pterygoid M., temporalis, chorda tympani N., and the otic ganglion

Action Elevates and retracts mandible Elevates mandible, biting, chewing Protracts and depresses th mandible Protracts and elevates mandible

Temporomandibular joint  Synovial joint between head of mandible and mandibualr fossa + tubercle of temporal bone  W/ articular disc, reinforced by lateral temporomandibular ligament  Functions both as hinge joint and gliding joint  Innervated by auriculotemporal and masseteric N. [from mandibular division of trigeminal N.] Other arteries of the mandibular region Name Distribution Maxillary A. 1st [mandibular part], 2nd [pterygoid part], 3rd [pterygopalatine part] [First part] Deep auricular A. Temporomandibular jt, ext. auditory meatus, tympanic membrane Anterior tympanic A. Tympanic cavity and tympanic membrane Middle meningeal Skull and dur mater, often damaged in fractures of temporal bone A. Accessory meningeal Semilunar [trigeminal] ganglion and dura mater A. Inferior alveolar A. Lower teeth, gums, chin and lower lip, mucous membrane of neck [Third part] Posterior Upper molars and premolars superior alveolar Infraorbital A. Lower eyelid, side of nose, upper lip, mucosa of mouth Pharyngel A. Roof of nasal cavity, nasopharynx and sphenoid sinus Artery of pterygoid canal Pharynx and auditory tube Sphenopalatine A. Major supply to nasal cavity and paranasal sinuses Descending palatine A. Soft and hard palates Clinical notes Mandibular N. lesions  Trigeminal neuralgia [tic douloureux] is characterized by episodes of sharp, stabbing pain that radiates over the areas innervated by sensory branches of maxillary or mandibular divisions of the trigeminal nerve.  Pain radiates over the mandible extending around the TMJ and deep to external ear. In others, pain radiate up to nostril and around the inferior aspect of the orbit.  Pain may be associated w/ the neuralgia is frequently triggered by moving the mandible, smiling or yawning or by cutaneous or mucosal stimulation. It may be caused by pressure or interruption of the blood supply to trigeminal ganglion.  A lesion of the motor root of mandibular nerve may result in weakness of muscles of mastication and a deviation of the jaw on protrusion toward the side of the injured nerve. Other structures of mandibular region Mandibular N. The only division of trigeminal N. to innervate skeletal muscle Trunk Gives rise to meningeal branch and N. to medial pterygoid Anterior division Deep temporal, masseteric, N. to lateral pterygoid, buccal N. Posterior division Auriculotemporal, lingual, inferior alveolar N. Meningeal branch Supplies dura and middle cranial fossa MENINGES Name Pia mater [vascular] Arachnoid mater [avascular] Dura mater or pachymeninx Epidural space Subdural space Subarachnoid space

Features Closely applied to brain surface, dips into fissures and sulci Delicate intermediate meningeal layer, w/ numerous arachnoid villi, separated from pia mater by subarachnoid space w/c contains CSF Tough CT layer that forms a sac around the brain, has no associated epidural space, consists of a meningeal and periosteal layer, encloses the dural venous sinuses Only a potential space because the dura fuses w/ periosteum lining inside of the skull, separates meningeal and periosteal layer of dura A real space, allows blood to collect [as in subdural hemorrhage] Space between arachnoid and pia mater, containd CSF

Clinical notes Headache  Meningeal dura is sensitive to pain. Irritation or stretching is a common cause of headache; pain is commonly referred to regions supplied by branches of trigeminal nerve. Subdural hematoma  Skull trauma may cause shearing of bridging veins at points where they enter dural venous sinuses; venous blood may accumulate in subdural space forming a crescent-shaped hematoma not bound by sutures of the skull.  Pxs w/ chronic subdural hematoma experience headache, impairment of cognitive skills, and gait instability. Cavernous sinus hrombosis  May result from infection that is transported from face to cavernous sinus by superior ophthalmic vein.  Pxs may initially experience an internal strabismus resuting from a lesion of abducens nerve.  Pxs may later exhibit loss of all ocular movements because of occulomotor and trochlear nerve involvement and pain & numbness in face and scalp due to involvement of ophthalmic and maxillary divisions of trigeminal nerve.  An infection in cavernous sinus may spread to other cavernous sinus thru intercavernous sinuses. Folds of dural mater Falx cerebri Tentorium cerebelli Falx cerebelli Diaphragma sellae

Btw cerebral hemispheres, encloses superior + inferior sagittal sinus Supports occipital lobes, encloses transverse sinus Btw cerebellar hemisphere, encloses occipital sinus Horizontal projection that forms the roof of hypophyseal fossa

Innervation of cranial dura Anterior cranial fossa Meningeal br. of anterior and posterior ethmoidal N. Middle cranial fossa Meningeal br. of mandibular N. Enters thru foramen spinosum Meningeal br. of maxillary N. Enters thru foramen rotundum Posterior cranial fossa Meningeal br. of vagus N. Enters thru jugular foramen Meningeal br. of upper cervical Enters thru hypoglossal canal Blood supply of cranial dural mater Name Origin Anterior meningeal A, Ant + post ethmoidal A. Middle meningeal A. Maxillary A. Accessory meningel A. Maxillary or middle Meningeal A. Posterior meningeal A. Ascending pharyngeal A. and occipital A.

Distribution Anterior cranial fossa Middle cranial fossa Middle cranial fossa including trigeminal ganglion Posterior cranial fossa

 Obstruction of central retinal A. or one of its branches will result in partial or complete blindness because there are no functional anastomoses between internal carotid and external carotid A. Exttraocular muscles Name Superior rectus Inferior rectus Medial rectus Lateral rectus Superior oblique Inferior oblique Levator palpebrae superioris

Innervation Occulomotor N. Occulomotor N. Oculomotor N. Abducens N. Trochlear N. Occulomotor N. Occulomotor N.

Action Elevates and adducts pupil Depreses and adducts pupil Adducts pupil Abducts pupil Depresses and abducts pupil Elevates and abducts pupil Elevates upper eyelid

Testing the function of extraocular muscles Lateral rectus Px is directed to look far laterally Medial rectus Px is directed to look far medially Superior rectus Px is directed to look far laterally and then downward Superior oblique Px is directed to look far medially and then downward Inferior oblique Px is directed to look far medially and then upward EYEBALL  Receives blood supply from branches of ophthalmic A.  Receives innervation from nasociliary N. [from ophthalmic nreve]  Walls of eyeball Fibrous tunic / outer fibrous layer Comprises the sclera and cornea Vascular tunic / middle pigmented Comprises the choroids, ciliary body, iris Inner tunic / inner vascular layer Formed by retina [optic, ciliary, iridial parts]  Chambers of the eyeball Anterior chamber Posterior chamber

Contains aqueous humor Contains aqueous humor

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Vitreous chamber

Contains gelatinous vitreous body

 Other important features of eyeball Optic disc Referred to as blindspot because it has no visual receptors [rods/cones], pierced by central artery of retina Macula lutea Yellow spot, has a central depression called fovea centralis Fovea centralis Area of maximum visual acuity, has cones and no rods Pupil Acted upon by sphincter pupillae and dilator muscles Cornea Transparent and vascular membrane of fibrous tunic Lens Transparent biconvex disc, exerted by ciliary body and susp. Lig. Accommodation reflex / Near response  Characterized by convergence of pupils to maintain binocular vision  Constriction of pupil by sphincter pupillae muscles  Rounding of lens by ciliary muscle w/c reduces tension exerted on lens  A parasympathetic response mediated by oculomotor nerve via ciliary ganglion Clinical notes Pupillary light deficits  Deficits in response of 1 or both pupils to light may be caused by lesion of either afferent or efferent components of light reflex.  Afferent papillary defect [Marcus Gunn pupil] may result from optic N. lesions confirmed by swinging flashlight test. When normal eye is exposed to light, both pupils constrict; however when the flashlight is swung to affected eye, both pupils paradoxically dilate.  Lesions to occulomotor N. may result in an efferent papillary defect. In these pxs, the pupil is dilated on affected side and does not constrict in response to light shown in the other eye. If the lesion is complete, px may have a “blown pupil”. Papilledema  Due to an increase in intracranial CSF pressure, a swelling nerve at optic disk caused by reduced venous return from the retina. Visual field defects  Complete nasal and temporal visual field deficits are anopsias. Deficits in nasal or temporal half of a visual field are hemianopsias. Deficits in a quadrant of temporal or nasal visual field are quadrantanopsias.  Lesions in retina produce scotomas [small spot-like deficits in a part of a temporal or nasal visual field of the eye.  Complete optic nerve lesion results in monocular anopsia.  Complete optic chiasmal lesion produces bitemporal heteronymous hemianopsias [because of L and R temporal hemifields].  Lesions in visual pathway past the chiasm produce contralateral and binocular homonymous deficits, in the same part of the L or R nasal and temporal hemifield. Therefore a complete lesion of R optic tract will resut in a L homonymous hemianopsia.

Inf. Pharyngeal constrictor Cricopharyngeus muscle Longitudinal muscles Salpingopharyngeus Palatopharyngeus Stylopharyngeus

Vagus N. Recurrent laryngeal N.

Constricts pharynx Prevents entry of air into esophagus during swallowing

Vagus N. Vagus N. Glossopharyngea l

Elevates pharynx in swallowing Elevates pharynx in swallowing Elevates larynx and pharynx

Innervation of pharynx Pharyngeal plexus Provides most of the innervation of pharynx, receives contribution from the pharyngeal branch of vagus N, glossopharyngeal N, and superior cervical ganglion Accessory N. Provides motor nerve supply to all pharyngeal M. except stylopharyngeus Maxillary N. Provides sensory to mucous membrane of nasopharynx Glosspharyngeal N. Provides sensory to mucous membrane of nasopharynx Vagus N. Provides sensory to mucous membrane around entrance of larynx Blood supply and lymphatics of pharynx Name Branches Ascending pharyngeal A. From medial surface of external carotid A. Other arteries Ascending palatine, superior thyroid, and inferior thyroid A. Pharyngeal venous plexus Drains pharynx, goes to IVC Lymphatic supply Deep cervical LN, retropharyngeal and pretracheal nodes

PTERYGOPALATINE FOSSA Anteriorly Posterior surface of maxilla Posteriorly Pterygoid process and greater wing of sphenoid Medially Perpendicular plate of palatine bone Laterally Pterygomaxillary fissure Superiorly Body of sphenoid and orbital process of palatine bone Inferiorly Greater palatine canal  contents: 3rd part of maxillary A., maxillary N. , pterygoplatine ganglion ORAL CAVITY Anterior Lateral Superiorly Inferiorly

Teeth and gums Teeth and gums Hard and soft palate Anterior 2/3 of tongue and guuter of the floor

NASOPHARYNX  Opens to the nose via posterior choanae  Boundaries: o Superior: adenoid in the roof o Lateral: Eustachian tube opening  Fossa of Rosenmuller  Tensor veli palatine  Waldeyer’s ring: imaginary ring composed of tonsils namely: Nasophartynx Oropharynx Nasopharyngeal/adenoids – unpaired Palatine/faucial tonsils – paired [prominent cryps Tubal/tonsils of Gerlach - paired where food particles may lodged]

Vestibule  lies between lips and cheeks externally and teeth and gums internally  receives opening of parotid duct opposite the upper and 2nd molar tooth Teeth  Functions of the teeth Incisors 8 [4 in upper, 4 in lower jaw] For cutting food Canines 4 [2 in upper, 2 in lower jaw] For cutting and tearing food Premolars 8 [4 in upper, 4 in lower jaw] For crushing food Molars 8 [deciduous], 12 [permanent] For chewing and grinding food NOTE: Koplik spots are found in 2nd upper molar

Clinical notes  radiosensitive tumor: nasopharyngeal CA  nasopharyngeal CA starts at fossa of Rosenmuller caused by EBV  elastic cartilage are seen in: epiglottis, ear pinna, Eustachian tube  hyaline cartilage are seen in: bronchi, larynx, trachea

Differences between deciduous and permanent teeth Deciduous teeth/milk teeth/baby teeth Permanent teeth 20 [2 incisors, 1 canine, 2 molars in each half 32 [2 incisors, 1 canine, 2 premolars, 3 molars in jaw] each half jaw] Erupt at 6 mos. and is finished at 2 yrs Erupts at age 6 and alre all present at age 12 [except the last mola] Shed and replaced by permanent teeth at 6 yrs Last molar [wisdom tooth] erupts until 18-20 yrs

Palatine tonsil  an accumulation of lymphoid tissue that lies in the tosillar fossa btw palatoglossal fold [ant] and palatopharyngeal fold [post] of the oropharynx  lies in muscular bed formed by superior pharyngeal constrictor muscles  Receives most of its blood supply from tonsillar branch of facial A. and ascending + descending palatine A, ascending pharyngeal A. and lingual A.  Innervated by tonsillar branches of glossopharyngeal N.  drained by lymph vessels in jugulogastric node Muscles of pharynx Name Circular muscles Sup. Pharyngeal constrictor Middle pharyngeal constrictor

Blood supply & innervaion of teeth Vessel Origin Sup. & inf. alveolar A. Branch of maxillary A., Sup. & inf. alveolar N Dental plexuses

Features Supplies both maxillary & mandibular teeth Supply maxillary & mandibular teeth

Innervation

Action

PALATE  Consists of bony plate and soft palate, separates oral cavity from nasal cavity Bony palate Anterior 2/3 of soft palate, contains the openings of incisive canal and greater and lesser palatine canals Soft palate Posterior 1/3 of palate, strengthened by palatine aponeurosis

Vagus N. Vagus N.

Constricts the pharynx Constricts the pharynx

Muscles of palate Name

Innervation

Action

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Levator veli palatini Vagus N. Tensor veli palatini N. to tnsor vli palatine Musculus uvulae Vagus N. Palatoglossus Vagus N. Palatopharyngeus Vagus N. NOTE: Muscles for mastication  Lateral pterygoids – opens mouth  Medial pterygoids – closes mouth Blood supply of palate Name Descending palatine A. Ascending palatine A. Nerves of palate Name Greater palatine N. Lessere palatine N. Nasopalatine N.

Elevates soft palate Tenses soft palate Elevates the uvulae Depresses the palate Elevates pharynx during swallowing

Branches Greater and lesser palatne A. None Canal Palatine canal Palatine canal Incisive canal

TONGUE Name Filiform papillae Fungiform papillae Valate papillae

Distribution Soft and hard palate Btw tensor and levator veli palatini

Distribution Hard palate and gums Soft palate Largest, Hard palate

Features Numerous, covers the ant. 2/3 of tongue on its upper surface Scattered on apex of tongue In its walls lie the taste buds

Other features of the tongue Foramen cecum Blind pouch lying at apex of sulcus terminalis, marks the origin of thyroid diverticulum [thyroglossal duct] Frenulum Midline mucosal fold w/c connects inferior surface of tongue to floor of mouth Sublingual gland Lies on upper surface of mylohyoid beneath the mucosa of the floor of mouth, supplied by sublingual A., innervated by submandibular ganglion Movements of the tongue Protrusion Retraction Refraction and elevation Depression

Genioglossus Styloglossus, hyaloglossus Styloglossus, palatoglossus Hyoglossus, genioglossus

Muscles of the tongue Extrinsic muscles Innervation Action Notes Palatoglossus Vagus N. Depresses palate, elevates tongue Pretty Styloglossus Hypoglossal N. Elevates and retracts tongue Sexy Genioglossus Hypoglossal N. Depresses and protrudes tongue Girl Hyoglossus Hypoglossal N. Depresses tongue Hiding Intrinsic muscles Innervation Action Sup. and inf. longitudinal Hypoglossal N. Alters shape of tongue Transverse and ertical Hypoglossal N. Alters shape of tongue NOTE: All extrinsic and intrinsic muscles of the tongue are innervated by hypoglossal nerve [except the palatoglossus, innervated by vagus via pharyngeal plexus] Innervation of tongue Mucosa of the anterior 2/3 Mucosa of posterior 1/3 Glosopharyngeal N. Hypoglossal N.

General somatic fibers: lingual N. [from mandibular N.] Taste fibers: facial N. [from chorda tympani and lingual N.] General visceral afferent: glossopharyngeal N. Taste fibers: glossopharyngeal N. Gives rise to pharyngeal branches to pharyngeal plexus, motor br. to stylophryngeus M., lingual branche to posterior 1/3 of tongue Supplies all extrinsic and intrinsic M. [except palatoglossus w/c is supplied by vagus N.]

Blood supply to tongue Name Origin Lingual A. External carotid A.

Branches Suprahyoid br., dorsal lingual A., deep lingual A., sublingual A.

Lymph drainage of tongue Tip of tongue Submental nodes Anterior 2/3 Submandibular and deep cervical nodes Posterior 1/3 Deep cervical nodes EXTERNAL NOSE  Consists of ala, dosum and bridge. Covered by ciliated pseudostratified-columnar epithelium [like epididymis] Floor Palatine process of maxilla, horizontal plate of palatine bone Roof Body of sphenoid, cribriform plate of ethmoid, frontal, nasal bone Lateral Superior, middle and inferior nasal conchae

Medial

Nasal septum

 Formed by nasal bones, frontal process of maxillae, nasal part of frontal bones  Cartilaginous skeleton formed by septal cartilage, lateral nasal cartilages, alar cartilages NASAL CAVITY  Extends from naris [nostril] anteriorly and choanae posteriorlly Vestibule Functions to filter incoming air Olfactory ganglion Conveys sense of smell Respiratory ganglion Covered by vascular and glandular resp. mucosa Nasal conchae Increases surface area of respiratory epithelium to facilitate warming & humidifying of the inhaled air Nasal meatuses Superior nasal Receives opening of posterior ethmoidal air cells meatus Middle nasal meatus Receives opening of frontal and maxillary, anterior and middle ethmoid air cells Inferior nasal meatus Receives opening of nasolacrimal duct Lymph drainage of nasal cavity Vestibule Submandibular nodes Remainder of nasal cavity Upper deep cervical nodes Innervation of nasal cavity Name General somatic afferent Parasymphathetic fibers Sympathetic fibers Olfactory nerve Maxillary nerve

Origin Branches of ophthalmic and maxillary nerves Facial N. via pterygopalatine ganglion Superior cervical ganglion Convey sense of smell [olfaction] Supplies lateral wall of nasal cavity; its branch Nasopalatine N. [largest] supplies nasal septum and hard palate Ophthalmic nerve Supplies both septum & lateral wall of nasal cavity & dorsum of nose Blood supply of nasal cavity Name Branches Sphenopalatine A. Lateral and posterior nasal A. , it is the most common source of bleeding in the posterior nasal cavity Anterior ethmoidal A. Medial and lateral branches Other arteries Greater palatine, superior labil, posterior ethmoidal A. Clinical notes Epistaxis  Occurs often in the anterior part of nasal septum anterior to inferior concha. This is the area where the distribuition of the septal branches of the sphenopalatine and labial arteries meet and is referred to as Kiesselbach’s area [maxillary A., ophthalmic & facial A.] PARANASAL SINUSES  Lined by mucoperiosteum covered respiratory epithelium  Innervated by maxillary and ophthalmic N.  Functions: reduce weight of the skull, serve as resonators for sound production, warm and humidify the inspired air 1. Maxillary sinus  Largest of paranasal sinuses and is present at birth  Drains into middle meatus of the nasal cavity thru semilunar hiatus  Supplied by superior alveolar and infraorbital nerves Roof Floor of orbit, contains infraorbital groove and canal Floor Contains elevations produced by roots of number of teeth Posterior Forms infratemporal surface of maxilla Anterior Contains roots of premolar and canine teeth Medial Contains opening of sinus into nasal cavity Lateral Lies in zygomatic process of the maxilla 2. Sphenoid sinus  Drains into nasal cavity thru sphenoethmoidal recess  Divided into L and R sinuses by deviated bony septum  Supplied by lateral posterior superior nasal N. [from maxillary N.], lateral posterior nasal A., and posterior ethmoidal nerve and artery [from ophthalmic A.] 3. Ethmoid sinus Name Anterior ethmoid cells Middle ethmoid cells Posterior ethmoidal

Opening Infundibulum [middle] Ethmoid bulla [middle] Superior meatus

Innervation Anterior ethmoidal N. and A. Anterior ethmoidal N. and A. Anterior ethmoidal N. and A.

4. Frontal sinus  Opens by way of frontonasal duct into the ethmoidal infundbulum of the middle meatus  Supplied by supratrochlear and supraorbital N. and A.

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Clinical notes Sinusitis  Maxillary sinus is a common site of sinusitis [inflammation of mucosa] that may result from infection or obstruction of ostium that drains the maxillary sinus. It has a poor gravitational drainage because the ostium of the sinus is situated on superior part of medial wall of the sinus.

External ear Auricle

Lymph drainage of the paranasal sinuses Name Drainage Maxillary sinus Middle meatus [hiatus semilunaris] Frontal sinus Middle meatus [infundibulum] Sphenoid sinuses Sphenoethmoidal recess Ethmoidal sinus Anterior group Infundibulum and middle meatus Middle group Middle meatus above bulla ethmoidalis Posterior group Superior meatus

Middle ear Tympanic membrane

LARYNX  Provides a protective sphincter at the inlet of air passages; also for voice production  Regulates the passage of air during: phoation [speech], and inspiration or expiration Laryngeal skeleton Thyroid cartilage Cricoid cartilage Arytenoids cartilage Epiglottic cartilage

Largest of the laryngeal cartilage Unpaired hyaline cartilage, lies at C6 level, ring-shaped Paired hyaline cartilage, pyramidal shaped Leaf-shaped cartilaginous plate

Laryngeal cavity and folds Vestibule Btw aditus [entrance from phaynx to laryx] and vestibular folds Vestibular fold Aka as false vocal cords, contains vestibular ligament and upper part of thyroarytenoid muscles. Rima vestibule – space btw paired vestibular fold Ventricle Btw vestibular fold and vocal cord. Saccule – evagination of the ventricle Ventricular Aka vocal fold or true vocal cord, contains the vocal ligament and vocalis part fold of thyroarytenoid muscles, produce thes sound of speech, controls air flow Rimma glottidis Interval btw paired vocal cords, narrowest part of laryngeal cavity, it opens and closes to regulate the passage of air Infraglottic Btw vocal fold and lower border of cricoid cartilage, continuous inferiorly w/ cavity trachea, related anteriorly to cricothyroid membrane Intrinsic & extrinsic muscles of larynx Name Innervation Action Cricothyroid Vagus N. Tenses and legthens vocal ligament Posterior cricoarythenoid Vagus N. Abducts the vocal cord Lateral cricoarythenoid Vagus N. Adducts vocal cord Transverse arythenoid Vagus N. Adducts the vocal cords Oblique arythenoid Vagus N. Adducts the vocal cords Thyroarythenoid Vagus N. Decreases tension and length of vocal lig. Vocalis Vagus N. Varies the length and tension of vocal cord Thyroepiglotticus Vagus N. Depresses the epiglottis Aryepiglotticus Vagus N. Depresses the epiglottis NOTE: All extrinsic muscles of larynx = recurrent laryngeal nerve except cricothyroid Cricothyoid – emergency airway for cervical injury Innervation of larynx Name Superior laryngeal N. Inferior laryngeal N.

Origin Vagus N. Recurrent laryngeal N.

Branches Internal and external laryngeal N. None

Clinical notes Superior laryngeal nerve lesions  Are largely asymptomatic because its fibers are mainly sensory. If motor fibers to cricothyroid are affected in a lesion of the external branch, a px may experience mild hoarseness and slight decrease in vocal strength w/ tendency to produce monotonous speech. Recurrent laryngeal nerve lesions  Both recurrent laryngeal nerves are susceptible to injury in surgical procedures involving thyroid gland. Lesions of recurrent laryngeal N. result in fixed vocal cord and transient hoarsness.  L recurrent laryngeal N. is injured more frequently than R because of its couse thru superior mediastinum.  In the mediastinum, the L recurrent laryngeal N. hooks around the arch of aorta and might be compressed by aortic aneurysm.  R recurrent laryngeal N. is found only in the neck, where it hooks around R subclavian A. Blood supply of larynx Name Origin Superior laryngeal A. Superior thyroid A. Inferior laryngeal A. Inferior thyroid A. EAR

Distribution Upper part of larynx Lower part of larynx

External acoustic meatus

Tympanic cavity Lateral wall Medial wall

Anterior wall Posterior wall Roof Floor Auditory ossicles Malleus [hammer] Incus [anvil] Stapes [stirrup] Inner ear Bony labyrinth

Collects sound waves and directs them to external auditory meatus, innervated by great auricular, auriculoyemporal and lesser occipital N. Consists of cartilaginous part [outer 1/3], bony part [inner 2/3], innervated by auriculotemporal N, auriculotemporal br. Of vagus N., supplied by superficial temporal, deep auricular and post. Auricular A. [Or tympanic cavity] Separates external acoustic meatus from tympanic cavity, conducts sound vibrations to ossicles of the middle ear, innervated by auriculotemporal N. and auricular br. Of vagus N. on outer surface and tympanic br. of glossopharyngeal N. on its inner surface Air-filled cavity w/in petrous temporal bone, contains the auditory ossicles, communicates w/ nasopharynx [via auditory tube], and mastoid air cells [via aditus ad anthrum] [membranous] Formed by tympanic membrane + epitympanic recess [labyrinthine] Separates tympanic cavity from inner ear Oval window/fenestra vestibule – closed by footplate of stapes Round/fenestra cochlea – closed by secondary tympanic membrane Cochleariform process – serves as pulley for tendon of tensor tympani Aka carotid wall, pierced by caroticotympanic canalliculus Aka mastoid wall, contains facial canal and pyramidal eminence Aka tegmental wall, formed by tegmen tympani Aka jugular wall, formed by jugular fossa of temporal bone Transmits the sound waves received at tympanic membrane to perilymph of ear, covered by mucous membrane Attaches to tympanic membrane Its body articulates w/ head of malleus Its neck receives th attachment of stapedius tendon

Contains the membranous labyrinth suspended in peilymph [K↓, Na↑ like ECF]. It includes cochlea, vestibule, and semicircular canals o Vestibular portion [pars superior] – balance o Cochlear portion [pars inferior] - hearing Membranous Contains the endolymph [K↑, Na↓, like ICF]. It includes cochlear duct, utricle labyrinth and semicircular ducts  Otolith organs [Saccule, Utricle - respond to Linear acceleration]  Semicircular canal [respond to Angular acceleration] NOTE: organ of corti – sensory organ of the ear; Gasserian ganglion – largest ganglion Muscles related to middle ear Stapedius muscle Contracts reflexly in response to loud sounds, innervated by facial N. Tensortympani M. Contracts reflexly in response to loud sounds, innervated by N. to tensor tympani [from N. of medial ptrygoid, br. of mandibular N.] Clinical notes Hyperacusis  The stapedius contracts reflexively to protect inner ear from high intensiy vibrations. A lesion of facial nerve, if it includes the nerve to stapedius, results in hyperacusis [increased sensitivity to loud sounds]. Types of hearing loss  Conductive hearing loss result from interference of sound transmission thru external or middle ear. Middle ear infections in children and otosclerosis in adults are the common causes.  Sensorineural hearing loss may result from loss of hair cells in cochlea or lesion to cochlear part of CN VIII or to CNS auditory pathways. Test to determine hearing loss type  Weber’s test – used to determine whether a px has a hearing loss but does not determine whether it is conductive or sensorineural. A vibrating tuning fork is placed in midline of the skull or on the bridge of nose; normally vibrations reach the normal ear by both bone and air conduction, but they interfere w/ each other making the normal ear less sensitive. Pxs w/ sensorineural hearing loss will hear the vibrations better in normal ear.  Rinne’s test – used to determine whether a px has a conductive hearing loss. The base of the vibrating tuning fork is placed on mastoid process. When the px no longer hears the vibrations, the tuning fork is then placed next to the external ear. Normally, airborne vibrations are heard better than those conducted thru skull bones because of the efficiency of middle ear, so the px should again hear the vibrations. If the px has condutive hearing loss, the tuning fork cannot be heard when placed next to external ear. Nerves related to middle ear Name Origin Tympanic N. Glossopharyngeal N. Lesser petrosal N. Tympanic N. Caroticotympanic N. Internal carotid plexus Facial N. Chorda tympani Facial N. Nerves related to inner ear Name Origin

Distribution Tympanic cavity, mastoid air cells, auditory tube Middle cranial fossa structures Anterior wall Petrous temporal bone area Infratemporal fossa Distribution

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Vestibulocochlear N. Vestibular N. Cochlear N.

Vestibular ganglion Vestibulocochlear N. Vestibulocochlear N.

Internal auditory meatus Macule and cristae ampullares Spiral organ of corti

RAPID REVIEW  Largest and most important interfascial space: retropharyngeal space  Congenital torticollis [wry neck] – flexion deformity of neck due to a fibrous tissue tumor  Spasmodic torticollis [cervical dystonia] – abnormal tonicity of neck involving trapezius and sternocleidomastoid muscles  MC iatrogenically injured nerve: Accessory N.  Serves as “internal barometer” when venous pressure rises: external jugular vein  Largest endocrine gland of the body: thyroid gland [C5-T1]  Largest branch of thyroid artery: inferior thyroid artery  Largest branch of vertebral A: posterior inferior cerebellar A.  An artifact found only in dried skull: foramen lacerum [in life it is filled w/ cartilage]  Principal muscle of cheeks: buccinator  Main nerve for secretomotor fibers of submandibular and sublingual glands: facial N.  Largest of the paired salivary glands: parotid gland  Stensen’s duct [parotid], wharton’s duct [submandibular]  Major retractor of the lower jaw: temporalis  Indirect trauma to orbital walls produces: blowout fracture  Common in boxers and basketball players: periorbital echymosis  Skeleton of eyelids: tarsal plates  Sensory nerve to eyeball: Nasociliary N.  Largest part of the vascular layer of eyeball, lines the sclera: Choroids  Ciliary processes: secretes aqueous humor w/c fills posterior eye chamber  Vitreous chamber: comprises the bulk of the eyeball  Fovea centralis: area of most acute vision [maximum visual acuity] – contains only cones, no rods  Prevents air entry into esophagus between swallowing: cricopharyngeus muscle  Entrance from pharynx into larynx: aditus  1st bones to be fully ossified: auditory ossicles  Smallest striated muscle of the body: stapedius  Skin is thin in eyelids and genitals  Skin is the largest organ  Facial nerve branches: Temporal, zygomatic, maxillary, mandibular, cervical Lesions in primary visual pathways  Sorbitol – sugar accumulation in lens in DM cataract  Glaucoma – diuretic of choice: acetazolamide  Central retinal artery lesion – blindness  Ophthalmologic emergencies – chemical burns and central retinal artery occlusion Amaurosis fugax – TIA of eyes  Temporal, parietal, occipital  Optic nerve – blindness in ipsilateral area  Optic chiasm – bilateral hemianopsia  Meyor’s loop – optic radiation   Optic pathway: o Cornea → lens → retina → optic nerve → optic chiasm → optic tract → lateral geniculate body → optic radiation → visual field  Flow of aqueous humor: o Choroids plexus → posterior chamber → iris → anterior chamber → canal of schelm → iricorneal junction → sclera  Flow of tears: o Excretory duct → fornix → cornea → conjunctiva → lacus lacrimalis → lacrimal puncta → lacrimal canaliculi → lacrimal sac → nasolacrimal duct→ inferior meatus of nose Clinical notes on the eyes Nystagmus Astigmatism Emetropia Myopia Hyperopia Presbyopia Diplopia Exopthalmus Pink eye / conjunctivitis Pterygium Keratitis Photophobia Kayser-fleisher rings

Rapid eyeball movement Defective curvature of refractive surface of the eye Norman vision Nearsigtedness [needs concave lens] Farsightedness [needs convex lens] Impaired vision due to old age Double vision due to paralysis of extraocular eye muscles Protrusion of eyeball seen in hyperthyroidism Palpebral conjunctival inflammation [mucus – bacteria, red – viral] White scar tissue in the eye Corneal inflammation Morbid fear of light as seen in rabies Rings around limbus as seen in 29ilson’s disease

Arcus seniles Diabetic retinopathy Horner’s syndrome Glaucoma Papilledema Hyphema

Benign peripheral corneal degeneration Uncontrolled sugar In blood causes fat deposition in retina Constricted pupil w/ sinking, redness and dryness of the eyes Blockage of drainage of aqueous humor Edema of retina due to increased ICP Hemorrhage of the anterior chamber of eye

Clinical notes on eyelids Ablepharon Absent eyelid Ankyloblepharon Fused eyelids Cryptholthalmos Overlying skin hiding the eye Coloboma 1 or both upper eyelid has vertical fissure Ectropion Eversion of eyelid Entropion Inversion of eyelid Distichiasis Accessory row of eyelashes Blespharitis Inflammation of lid margin affecting Meibonian gland Hordeolum / stye Acute, solitary, circumscribed glands of Beis [ciliary glands] Chalazion Chronic granulosa/cysts of Meibonian glands Ptosis Drooping of eyelid involving CN 3 [occulomotor nerve] MISCELLANEOUS Summary of important landmarks Linea semilunaris Spleen Kidney Tracheal bifurcation Oropharynx Laryngopharynx Thyroid gland Cricoid cartilage, trachea starts Superior angle of scapula Suprasternal or jugular notch Spine of scapula Sternal angle of Louis, trachea ends Tracheal bifurcation Inferior angle of scapula, IVC passes Xiphisternal joint Abdominal aorta, celiac A. Duodenum Pancreas, SMA, spinal cord in adults end Spinal dura Lowest costal margin [10th rib], IMA Common iliac artery Sacral promontory Recto-Sigmoid colon

Crosses costal margin near tip of 9th costal cartilage Axis of ribs 9-12, Upper 3 lumbar vertebrae Sternal angle C2-3 vertebrae C4, 5, 6 vertebrae C5-T1 C6 vertebrae T2 T2/3 T3 2nd costal cartilage & lower border of T4/T5 T6 T8 T9 T12 & divides at L4 into R and L common iliac A. L1-L2 [2nd part is at bodies of L1,2,3 Level of L1 L2 L3 L4 S2-3 S3

Dermatomes C2 Back C5 Tip of shoulder, perianal region C6 Thumb C7 Middle finger C8 Small finger T4 Nipple T7 Xiphoid process T10 Umbilicus L1 Inguinal ligament L4-5 Big toe, kneecaps S1 Small toe S2, 3, 4 Erection & sensation of penile zones Most common Most mobile segment of omentum MC bone injury invoving the face MC nerve involved in TOS Most posterior cavity w/in peritoneal cavity Most posterior extension of lateral thyroid lobule MC carpal bone dislocation MC carpal bone fracture MC tarsal bone fracture MC fractured bone MC damaged nerve in px w/ shoulder dislocation Firs carpal bone to ossify [at 1st year of life]

R lower segment Nasal bone trauma Ulnar nerve Morrison’s pouch Tubercle of Zuckerkandl Lunate Scaphoid Calcaneus Clavicle Axillary nerve Capitate

IMPORTANT MNEUMONICS

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Aoric branches  Aortic arch gives off the Bracheiocephalic trunk, the left Common Carotid, and the left Subclavian artery [ABC'S] Axillary artery branches [from proximal to distal]  Superior thoracic, Thoracoacromial, Lateral thoracic, Subscapular, Anterior circumflex humeral, Posterior circumflex humeral [Screw The Lawyer, Save A Patient] Thoracoacromial artery branches  Clavicular Acromial Pectoral Deltoid [CAlifornia Police Department] Subclavian artery branches [Very Tired Individuals Sip Strong Coffee Served Daily]  Vertebral artery  Thyrocervical trunk ---Inferior thyroid ---Superficial cervical ---Suprascapular  Costocervical ---Superior intercostal ---Deep cervical Coeliac trunk branches  Left gastric artery, Hepatic artery, Splenic artery [Left Hand Side] Internal iliac artery branches  ileolumbar, Lateral sacral, Gluteal [superior and inferior], Pudendal [internal], Inferior vesical [uterine in females], Middle rectal, Vaginal, Obturator, Umbilical [I Love Going Places In My Very Own Underwear] Superior thyroid A. branches:  Muscular, Infrahyoid, Superior laryngeal, Sternomastoid, Cricothyroid, Glandular [May I Softy Squeeze Charlie’s Glans] External carotid A. branches  Superior thyroid, Lingual, Facial, Ascending pharyngeal, Occipital, Posterior auricular, Superficial temporal, Maxillary [Shiela Lies Flat As Oscar’s Penis Stops Masturbating] Femoral artery deep branches [Put My Leg Down Please]  Profundus femoris (deep femoral artery)  Medial circumflex femoral artery  Lateral circumflex femoral artery  Descending genicular arteries  Perforating arteries Lumbar plexus branches  Iliohypogastric, Ilioinguinal, Genitofemoral, Lateral femoral cutaneous, Obturator, Femoral [I Get Laid On Fridays] Trigeminal Nerve: where branches exit the skull  Superior obital fissure [V1], foramen Rotundum [V2], foramen Ovale [V3] [Standing Room Only] Vagus Nerve: pathway into thorax  Left Vagus nerve goes to Anterior descending into the thorax [I Left my Aunt in Vegas] Facial nerve branches  Temporal branch, Zygomatic, Buccal mandibular [Two Zombies Bugging] Deep tendon reflexes: root supply "1, 2, 3, 4, 5, 6, 7, 8":  S1-2: ankle  L3-4: knee  C5-6: biceps, supinator  C7-8: triceps Bronchopulmonary segments of right lung

 In order from superior to inferior: Apical Posterior Anterior Lateral Medial Superior Medial basal Anterior basal Lateral basal Posterior basal [A PALM Seed Makes Another Little Palm] Wrist bones [prone to avascular necrosis]  Scaphoid, Lunar, Triquetrum, Pisiform, Trapezoid, Trapezium, Capitate, Hammate [Some Lovers Try Position That They Can’t Handle] Carpal bones [multangular names]  Navicular, Lunate, Triquetrum, Pisiform, Greater Multangular [trapezium], Lesser Multangular [trapezoid], Capitate, Hamate

Tarsal bones [superior to inferior, medial to laeral]  In order (right foot, superior to inferior, medial to lateral): Talus Calcanous Navicular Medial cuneiform Intermediate cuneiform Lateral cuneifrom Cuboid [Tall Californian Navy Medcial Interns Lay Cuties] Elbow  Muscles that bend/flex it: 3B’s - Brachialis, Biceps, Brachioradialis Ureter to ovarian/ testicular artery  Ureters [water] is posterior to it Kidney hilums at transpyloric plane L1  L1 goes thru hilum of only 1 kidney and it’s the left Erector spinae muscles  Iliocostalis, Longissimus, Spinalis [I Love Sex – lateral to medial] Scrotum layers  From superficial to deep: Skin Dartos External spermatic fascia Cremaster Internal spermatic fascia Tunica vaginalis Testis [Some Damn Englishman Called It The Testis] Collagen types [memorize]  Type 1 – bone = 90% of tendon and fascia  Type 2 = car Two lage, caritilage, vitreous body, nucleous pulposus  Type 4 – under the floor, bone marrow, basal ganglia  K+ – epidermal plates Internal jugular vein: tributaries  From inferior to superior: Middle thyroid Superior thyroid Lingual Common facial Pharyngeal Inferior petrosal sinus [Medical Schools Let Confident People In] Inferior vena cava tributaries [I Like To Rise So High]  Illiacs, Lumbar, Testicular, Renal, Suprarenal, Hepatic vein. Carotid sheath contents [I See 10 CC's in the IV]  I See (I.C.) = Internal Carotid artery  10 = CN 10 (Vagus nerve)  CC = Common Carotid artery  IV = Internal Jugular Vein Retroperitoneal structures list [SAD PUCKER]  Suprarenal glands, Aorta & IVC, Duodenum (half), Pancreas, Ureters, Colon (ascending & descending), Kidneys, Esophagus (anterior & left covered), Rectum Superior mediastinum: contents [PVT Left BATTLE]  Phrenic nerve, Vagus nerve, Thoracic duct, Left recurrent laryngeal nerve (not the right), Brachiocephalic veins, Aortic arch (and its 3 branches), Thymus, Trachea, Lymph nodes, Esophagus Diaphram aperatures: spinal levels [Come Enter the Abdomen]  Vena Cava [8], Esophagus [10], Aorta [12] Superior orbital fissure  Lacrimal nerve, Frontal nerve, Trochlear nerve, Superior branch of occulomotor nerve, Abducent nerve, Nasociliary nerve, Inferior branch of occulomotor nerve [Live Free To See Absolutely No Insult] Cubital fossa contents [My Bottoms Turned Red]  From medial to lateral: Median nerve, Brachial artery, Tendon of biceps, Radial nerve Posterior mediastinum structures  There are 4 birds:  The esophaGOOSE (esophagus)  The vaGOOSE nerve  The azyGOOSE vein  The thoracic DUCK (duct) Tarsal tunnel: contents  From superior to inferior: Tibialis posterior, flexor Digitorum longus, posterior tibial Artery, tibial Nerve, flexor Hallucis longus [Tiny Dogs Are Not Hunters] Spermatic cord contents [Piles Don't Contribute To A Good Sex Life]  Pampiniform plexus, Ductus deferens, Cremasteric artery, Testicular artery, Artery of the ductus deferens, Genital branch of the genitofemoral nerve, Sympathetic nerve fibers, Lymphatic vessels

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