Anatomy Finals Complete Qa With Notes Mcnotes

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Superficial Back Q: The general name for an alternate pathway of blood flow in or around an organ, around a joint, or past an obstruction is called: A: Collateral Circulation When the body moves, vessels in certain locations may become constricted. Collateral circulation allows blood to flow around potential constrictions, such as at moveable joints. An arteriovenous anastomosis is a shunt between arterioles and venules that can divert blood away from a capillary bed. A periarticular network sounds good, and is pretty much descriptive of collateral circulation, but it's not the winner. A perivascular plexus is a collection of autonomic nerve fibers that follow blood vessels to reach a target to innervate (including the vessels themselves). A venous plexus is a network of small veins - the internal vertebral plexus around the dural sac is a good example. Q: When standing in the Anatomical Position the palms of the hands face: A: Anteriorly In the anatomical position, position, the body stands erect, upper limbs at the sides, palms facing forward or anteriorly, thumbs pointing away from the body. Q: The regionally named layer of tissue which encloses and binds muscle groups together is the: A: Deep Fascia Deep fascia is a dense layer of connective tissue that invests structures such as the muscles. Intermuscular septae are specific fascial planes that separate groups of muscles into different compartments, a concept that will be very important for understanding the limbs. A neurovascular bundle is a combination of a nerve and vasculature (arteries, veins, and lymphatics) which may travel together in a packet. These bundles may vary in size and do not always contain all of these elements. Skin is the most superficial structure of the body, and it is comprised of the epidermis and dermis. The subcutaneous tissue, also known as the hypodermis or superficial fascia, is the mostly fat filled layer which lays directly underneath the skin. Although skin and subcutaneous tissue cover the muscles, these layers do not directly invest and enclose regional muscle groups--that's the job of the deep fascia. Q: Hair, nails and teeth (enamel) originate in common with what layer? A: Epidermis Ectoderm is the embryonic layer that gives rise to skin, nails, hair, and the enamel of teeth, as well as some nervous and connective tissues, and even a type of endocrine tissue (suprarenal medulla). Q: The cutaneous branch of the posterior primary ramus of C2 is called the: A: The greater occipital nerve The greater occipital nerve is the dorsal primary ramus of spinal nerve C2--it provides cutaneous innervation to the skin of the back of the head. The accessory nerve is cranial nerve XI--it innervates trapezius. The great auricular nerve, the lesser occipital nerve, and ansa cervicalis are all structures from the cervical plexus, which is made of ventral primary rami. They will be studied with the head and neck. Q: In order to make an intramuscular injection, the needle must pass through several layers of tissue to reach the muscle. Choose the correct order of tissues the needle would pass through from superficial to deep. A: Epidermis, dermis, subcutaneous tissue, investing fascia, muscle The first layer through which the needle must cross is the skin, composed of the superficial epidermis and deeper dermis. Then comes the subcutaneous tissue--it's filled with fat and fairly loose. Finally, the investing fascia covers the muscle. Remember this sequence to keep yourself oriented when thinking about the different layers of skin and fascia! Q: From your observations while removing the skin from the cadaver, in which area did you find the skin to be the thickest? A: posterior surface of the neck and scalp Other than the palms of the hands and the soles of the feet, skin is thickest on the upper back, posterior neck and scalp. Why is a good question - perhaps it's an evolutionary adaptation for defense against back stabbing.

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Q: Loss of function, paralysis, of which muscle would result in drooping or sagging of the shoulder? A: trapezius The trapezius, innervated by the accessory nerve (CN XI), is the muscle responsible for elevating the tip of the shoulder. Erector spinae, which is innervated by the dorsal primary rami of C1-S5, extends and laterally bends the trunk, head and neck. Latissimus dorsi, innervated by the thoracodorsal nerve, allows the trunk to be lifted up to the arms (like with climbing or pull-ups). Levator scapulae, innervated by the dorsal scapular nerve, elevates the scapula. Rhomboidus major and minor are both innervated by the dorsal scapular nerve and aid trapezius in retracting the scapula. Deep Back and Spinal Cord Q: Which muscle is innervated by posterior primary rami? A: erector spinae Of all the answer choices, erector spinae is the only true back muscle listed. True back muscles act on the vertebral column, producing its movements and maintaining posture. These true back muscles are innervated by posterior (dorsal) primary rami. The other four muscles are superficial back muscles that aid with the movements of the limbs as well as with respiration. They mostly receive their nerve supply from the ventral rami of cervical nerves. Latissimus dorsi is innervated by the thoracodorsal nerve, which is made from branches of the ventral primary rami of C5 and C6. Levator scapulae and rhomboideus major are innervated by the dorsal scapular nerve, a branch of the ventral primary rami of C5. (The superior part of levator scapulae also receives some innervation from the ventral primary rami of C3 and C4.) Lastly, trapezius is innervated by the accessory nerve (CN XI) but also receives innervation from C3 and C4 ventral primary rami for proprioception. Q: Which structure does NOT contain efferent autonomic nerve fibers? Dorsal ramus of C4 Dorsal root of T6 Ventral root of T3 Ventral ramus of L2

A: Dorsal root of T6 The dorsal root of a spinal nerve contains afferent sensory nerve fibers and no efferent autonomic nerve fibers. The efferent autonomic nerve fibers, which originate in the lateral horn of the spinal nerve, travel out of the spinal cord through the ventral root of the spinal nerve. As the ventral and dorsal roots join to form the spinal nerve, the fibers from both roots intermingle, and the dorsal and ventral primary rami take a mix of fibers, including afferent sensory fibers from the dorsal root, and efferent motorfibers from the ventral root. Postganglionic sympathetic efferent fibers  join each spinal nerve v ia a gray ramus communicans . So, all of the other nerves listed do contain ef ferent autonomic fibers. Q: The clavipectoral fascia is penetrated by which artery? A: thoracoacromial artery The thoracoacromial artery pierces the clavipectoral fascia before giving off its four branches: pectoral, clavicular, deltoid, and acromial. It supplies pectoralis major, pectoralis minor, the deltoid muscle, and the acromioclavicular joint. acromioclavicular  joint. It is a branch off of the axillary artery. The axillary artery and all its other branches, including the anterior circumflex humoral and subscapular arteries, run deep to the clavipectoral fascia. The thoracodorsal artery is a branch of the subscapular artery which also runs deep to the fascia.

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Q: Loss of function, paralysis, of which muscle would result in drooping or sagging of the shoulder? A: trapezius The trapezius, innervated by the accessory nerve (CN XI), is the muscle responsible for elevating the tip of the shoulder. Erector spinae, which is innervated by the dorsal primary rami of C1-S5, extends and laterally bends the trunk, head and neck. Latissimus dorsi, innervated by the thoracodorsal nerve, allows the trunk to be lifted up to the arms (like with climbing or pull-ups). Levator scapulae, innervated by the dorsal scapular nerve, elevates the scapula. Rhomboidus major and minor are both innervated by the dorsal scapular nerve and aid trapezius in retracting the scapula. Deep Back and Spinal Cord Q: Which muscle is innervated by posterior primary rami? A: erector spinae Of all the answer choices, erector spinae is the only true back muscle listed. True back muscles act on the vertebral column, producing its movements and maintaining posture. These true back muscles are innervated by posterior (dorsal) primary rami. The other four muscles are superficial back muscles that aid with the movements of the limbs as well as with respiration. They mostly receive their nerve supply from the ventral rami of cervical nerves. Latissimus dorsi is innervated by the thoracodorsal nerve, which is made from branches of the ventral primary rami of C5 and C6. Levator scapulae and rhomboideus major are innervated by the dorsal scapular nerve, a branch of the ventral primary rami of C5. (The superior part of levator scapulae also receives some innervation from the ventral primary rami of C3 and C4.) Lastly, trapezius is innervated by the accessory nerve (CN XI) but also receives innervation from C3 and C4 ventral primary rami for proprioception. Q: Which structure does NOT contain efferent autonomic nerve fibers? Dorsal ramus of C4 Dorsal root of T6 Ventral root of T3 Ventral ramus of L2

A: Dorsal root of T6 The dorsal root of a spinal nerve contains afferent sensory nerve fibers and no efferent autonomic nerve fibers. The efferent autonomic nerve fibers, which originate in the lateral horn of the spinal nerve, travel out of the spinal cord through the ventral root of the spinal nerve. As the ventral and dorsal roots join to form the spinal nerve, the fibers from both roots intermingle, and the dorsal and ventral primary rami take a mix of fibers, including afferent sensory fibers from the dorsal root, and efferent motorfibers from the ventral root. Postganglionic sympathetic efferent fibers  join each spinal nerve v ia a gray ramus communicans . So, all of the other nerves listed do contain ef ferent autonomic fibers. Q: The clavipectoral fascia is penetrated by which artery? A: thoracoacromial artery The thoracoacromial artery pierces the clavipectoral fascia before giving off its four branches: pectoral, clavicular, deltoid, and acromial. It supplies pectoralis major, pectoralis minor, the deltoid muscle, and the acromioclavicular joint. acromioclavicular  joint. It is a branch off of the axillary artery. The axillary artery and all its other branches, including the anterior circumflex humoral and subscapular arteries, run deep to the clavipectoral fascia. The thoracodorsal artery is a branch of the subscapular artery which also runs deep to the fascia.

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Q: During a motorcycle accident, an 18-year-old male landed on the right lateral side of his rib cage with his right upper limb abducted. In the hospital he was found to have "winging" of the right scapula. Which nerve was likely damaged in the accident? A: Long thoracic nerve An injury to the long thoracic nerve denervates serratus anterior, meaning that there will be no muscle protracting the scapula and counteracting trapezius and the rhomboids, powerful retractors of the scapula. This means that the scapula will be winged backwards, which is this patient's main symptom. The long thoracic nerve is derived from the nerve roots of C5-7. This nerve is particularly vulnerable to iatrogenic injury during surgical procedures, such as mastectomies, because it is located on the superficial side of serratus anterior. The accessory nerve innervates trapezius--an injury to this nerve might lead to an inability to raise the acromion  of the shoulder. The lateral pectoral nerve is a small nerve that provides innervation to pectoralis major. The acromion of phrenic nerve innervates the diaphragm. The vagus nerve provides nerve provides parasympathetic innervation to the thorax and much of the abdominal viscera. The patient's symptoms do not fit with an injury to any of these nerves. Q: In the axilla the pectoralis minor is a landmark, being closely related to all of the following structures except: cephalic vein cords of the brachial plexus lateral thoracic artery medial pectoral nerve second part of the axillary artery A: cephalic vein The cephalic vein is the only structure listed that does not have a special relationship to pectoralis minor. The cords of the brachial plexus are found deep to pectoralis minor. The second part of the axillary artery is defined as the segment of the axillary artery which is covered by the pectoralis minor muscle. So, branches of the second part of the axillary artery, including the lateral thoracic artery, lie deep to pectoralis minor. The medial pectoral nerve pierces pectoralis minor to reach pectoralis major. Superficial Limbs Q: After trying to throw a curve ball, a pitcher lost sensation from the tip of the little finger. This indicates injury to which nerve? A: Ulnar nerve The ulnar nerve innervates the medial 1.5 digits on the palmar surface of the hand, and 2.5 digits on the dorsal side. So, this is the nerve responsible for innervating the tip of the little finger. The radial nerve innervates the dorsal side of the lateral 2.5 digits, but does not innervate the tips of these fingers. The median nerve, which innervates the palmar side of the lateral 3.5 digits, also innervates the fingertips of these 3.5 fingers. The musculocutaneous nerve does not provide cutaneous innervation to the skin, but its branch, the lateral antebrachial cutaneous nerve, innervates the lateral skin of the forearm. The medial antebrachial cutaneous nerve innervates the medial skin of the forearm " this nerve is a direct branch of the medial cord of the brachial plexus.

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Q: Varicosities in the subcutaneous veins of the medial thigh were observed at physical examination. The vein involved was most likely the: A: greater saphenous Remember: subcutaneous venous varicocities occur in the superficial veins due to valve failure in the perforating veins! Varicose veins can be caused by activities that allow blood to pool in the legs, like excessive standing. Since the greater saphenous vein is a superficial vein on the anteromedial side of the leg and thigh, it's our winner! The femoral vein is a deep vein that drains much of the thigh. It is not a vein that would become varicose. The lesser saphenous vein is a superficial vein that runs up the middle of the posterior leg. It could be the cause of varicose veins on the posterior lower leg. The popliteal vein is a deep vein behind the knee which receives the lesser saphenous vein and eventually becomes the femoral vein. It is deep in the leg, so it's not the type of vein that would become varicose. Finally, the pudendal veins drain the external genitalia--they are not really relevant here.

Axilla, posterior Shoulder, arm Q: The cords of the brachial plexus are: A: at or below the clavicle, closely related to the axillary artery The cords of the brachial plexus are closely related to the axillary artery, at or below the level of the clavicle. You should have seen this in the dissection--the cords were wrapped around the axillary artery. The axillary vein is anterior to the axillary artery and is not associated with the cords of the brachial plexus. As far as the scalene muscles go, you'll learn more about this in the head and neck, but know that the roots, not the cords, of the brachial plexus are the structures found between the anterior and middle scalene muscles. Q: An open arterial anastomosis in the shoulder occurs between the suprascapular artery and which other artery? A: circumflex scapular The circumflex scapular artery, the dorsal scapular artery, and the suprascapular artery create arterial anastomoses around the scapula. This means that the scapula will be supplied with blood even if one of these arteries is ligated. Additionally, if the subclavian or axillary artery needs to be ligated, blood can flow from the dorsal scapular artery and suprascapular artery to the circumflex scapular artery. This effectively shunts blood from the first part of the subclavian artery to the third part of the axillary artery so that the upper limb will still receive blood. The connection between the suprascapular and circumflex scapular arteries is termed an open anastomosis because it is grossly visible, compared to the anastomosis with the dorsal scapular, which typically happens within small vessels. The anterior circumflex humeral artery supplies the deltoid muscle. It originates from the third part of the axillary artery and anastomoses with the posterior circumflex humeral artery. The thoracodorsal artery is a branch of the subscapular artery that supplies latissimus dorsi. The transverse cervical artery is a branch of the thyrocervical trunk that occasionally gives rise to the dorsal scapular artery. None of these arteries contribute to the scapular anastomoses.

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Q: The long thoracic nerve innervates which muscle? A: Serratus anterior Serratus anterior is innervated by the long thoracic nerve. Serratus anterior keeps the scapula held forward, balancing trapezius and the rhomboids which retract the scapula. If the long thoracic nerve is injured (which is common in surgery, since the long thoracic nerve is on the superficial side of serratus anterior), you may see a "winged scapula" protruding posteriorly. The anterior scalene muscle is innervated by C5-C7, and the middle scalene is innervated by C3-C8. Teres major is innervated by the lower subscapular nerve from the posterior cord of the brachial plexus. Subscapularis is innervated by the upper and lower subscapular nerves from the posterior cord of the brachial plexus. Q: The nerve which passes through the quadrangular space of the posterior shoulder innervates which muscle? A: Deltoid The quadrangular space is bounded medially by the tendon of the long head of the triceps, laterally by the humerus, superiorly by teres minor, and inferiorly by teres major. The posterior circumflex humeral artery and the axillary nerve traverse this space. The axillary nerve innervates 2 muscles: deltoid and teres minor. So, deltoid is the answer! Infraspinatus and supraspinatus are both innervated by the suprascapular nerve, off the superior trunk of the brachial plexus. Subscapularis is innervated by the upper and lower subscapular nerves, off the posterior cord of the brachial plexus. Teres major is also innervated by the lower subscapular nerve. Q: The axillary nerve arises directly from which part of the brachial plexus? A: posterior cord The axillary nerve and radial nerve are both terminal branches from the posterior cord. There are no nerves from the inferior trunk. The lateral cord gives off the musculocutaneous nerve and contributes a branch to the median nerve. The medial cord of the brachial plexus terminates with the ulnar nerve and a branch to the median nerve; it also gives off the medial pectoral nerve, the medial cutaneous nerve of the arm, and the medial cutaneous nerve of the forarm. The middle trunk of the brachial plexus has no direct branches. There is no superior cord of the brachial plexus--only a superior trunk! Q: Which of the following is not a direct branch of the axillary artery? anterior circumflex humeral posterior circumflex humeral thoracoacromial thoracodorsal subscapular A: thoracodorsal The thoracodorsal and circumflex scapular arteries are branches of the subscapular artery, which comes directly off the third segment of the axillary artery. The anterior and posterior circumflex humeral arteries are also direct branches of the third segment of the axillary artery. The thoracoacromial artery is a branch of the second part of the axillary artery.

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Q: If the second part of the axillary artery was interrupted, collateral blood flow could pass from branches of the thyrocervical trunk into which artery? A: Circumflex scapular One branch of the thyrocervical trunk is the suprascapular artery. This artery contributes to the scapular anastamosis with the dorsal scapular artery and the circumflex scapular artery. The circumflex scapular artery is a branch of the subscapular artery, which comes from the third part of the axillary artery. So, blood could flow from the suprascapular artery, through the scapular anastamosis, into the circumflex scapular artery, travel retrograde through the circumflex scapular artery and the subscapular artery, and reach the third part of the axillary artery. This would bypass any problems in the second part of the axillary artery. See Netter Plate 410B for a picture of this. The anterior and posterior humeral circumflex arteries are both branches of the third part of the axillary artery. These two arteries anastomose with each other. They would not help shunt blood from the first to the third part of the axillary artery. The deep brachial artery is a branch of the brachial artery found in the deep arm. The thoracoacromial artery is a branch of the second part of the axillary artery. None of these other arteries would help shunt blood over an interruption in the second part of the axillary artery. Q: In a fracture of the surgical neck of the humerus, which artery may be injured? A: Posterior circumflex humeral The posterior and anterior circumflex arteries wrap around the humerus near its surgical neck. A fracture to the surgical neck could damage either of these arteries or the axillary nerve. (Remember--the posterior circumflex humeral artery and the axillary nerve cross through the quadrangular space together.) The subscapular artery is a branch of the third part of the axillary artery--it branches to form the thoracodorsal artery and the circumflex scapular artery. The radial recurrent artery is a branch of the radial collateral artery--it contributes to collateral circulation around the elbow. The deep brachial artery is an artery in the deep arm--it is close to the humerus, so fracturing the humerus at mid-arm might result in damage to this vessel. Q: In a fracture of the midshaft of the humerus, which artery is most likely to be injured? A: Deep brachial The deep brachial artery is an artery in the deep arm, wrapping around the humerus in the radial groove. It is close to the humerus, so fracturing the humerus at mid-arm might result in damage to this vessel or the radial nerve. The subscapular artery is a branch of the third part of the axillary artery--it branches to form the thoracodorsal artery and the circumflex scapular artery. The posterior and anterior circumflex arteries wrap around the humerus near its surgical neck. A fracture to the surgical neck could damage either of these arteries or the axillary nerve. The radial recurrent artery is a branch of the radial collateral artery--it contributes to anastomoses around the elbow. The circumflex scapular artery is a branch of the subscapular artery. It travels to the posterior scapula to contribute to the scapular anastomosis. Q: The rotator cuff is composed of all of the following muscles except: A: teres major Teres major is not part of the rotator cuff. It does not insert on the greater or lesser tubercle of the humerus--instead, it inserts on the crest of the lesser tubercle of the humerus, which is distal to the lesser tubercle. It is innervated by the lower subscapular nerve and it is a medial rotator of the arm.

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The other four muscles comprise the rotator cuff--they all insert on the greater or lesser tubercles of the humerus. Supraspinatus inserts into the upper facet of the greater tubercle of the humerus and into the capsule of the shoulder joint. Infraspinatus inserts into the middle facet of the greater tubercle of the humerus and into the capsule of the shoulder joint. Teres minor inserts into the lower facet of the greater tubercle of the humerus and into the capsule of the shoulder joint. Subscapularis inserts onto the lesser tubercle of the humerus. Forearm and wrist Q: The anterior interosseous is a branch of which nerve? A: median The anterior interosseous nerve is a branch of the median nerve that provides motor innervation to the deep muscles in the flexor compartment, including flexor pollicis longus, the radial half of flexor digitorum profundus, and pronator quadratus. The other related nerve to think about is the posterior interosseous nerve, which is the terminal branch of the deep radial nerve. It provides sensory innervation to the wrist area. Q: What muscle is innervated by branches of both the median and ulnar nerves? A: Flexor digitorum profundus The median and ulnar nerve both innervate flexor digitorum profundus. Flexor carpi ulnaris is innervated by the ulnar nerve only. Flexor digitorum superficialis and flexor pollicis longus are innervated by the median nerve. Pronator quadratus is innervated by the anterior interosseus nerve, which is a branch of the median nerve. Q: The pulse of the radial artery at the wrist is felt immediately lateral to which tendon? A: Flexor carpi radialis The radial artery runs on the radial side of the wrist, lateral to the tendon of flexor carpi radialis. So, the radial pulse will be felt immediately lateral to this tendon. Remember--the radial artery enters the wrist on the anterior side. This means that the extensor tendons, which are on the posterior side of the wrist, will not be involved with the radial artery! The tendons for flexor digitorum profundus and superficialis are found more towards the center of the wrist, not on the wrist's lateral side. These tendons cross under the flexor retinaculum to reach the hand. Q: If the medial epicondyle of the humerus is fractured and the nerve passing dorsal to it is injured, which muscle would be most affected? A: Flexor carpi ulnaris The nerve passing dorsal to the medial epicondyle of the humerus is the ulnar nerve. In the forearm, the ulnar nerve innervates flexor carpi ulnaris and the ulnar side of flexor digitorum profundus. So, flexor carpi ulnaris would be most affected if the ulnar nerve was disrupted. What other symptoms might you see? Paralysis of hand muscles (except for the thenar compartment and the first two lumbricals) and numbness over the ulnar 1.5 digits in the hand! The extensor muscles (extensor digitorum and extensor carpi ulnaris) are in the posterior compartment of the forearm--they are innervated by the radial nerve. Flexor digitorum superficialis is innervated by the median nerve only. Although the ulnar side of flexor digitorum profundus would be impaired following the injury, the radial side of flexor digitorum profundus would still be innervated by the median nerve.

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Q: The main source of blood to the superficial palmar arterial arch is the: A: ulnar artery The ulnar artery is the main source of blood to the superficial palmar arterial arch; the arch is completed on the radial side by the superficial palmar branch of the radial artery. The radial artery is the main source of blood to the deep palmar arterial arch, which is completed on the ulnar side by the deep branch of the ulnar artery. Q: The signs and symptoms of carpal tunnel syndrome may vary among patients, but they always result from compression of what structure in the carpal canal? A: Median nerve Carpal tunnel syndrome is caused by a compression of the median nerve within the carpal tunnel. The carpal tunnel is a canal on the anterior side of the wrist. It is made of the carpal bones which are covered by the flexor retinaculum. It contains the tendon of flexor pollicis longus, the tendons of flexor digitorum superficialis and profundus, and the median nerve. If the sheath over the common flexor tendons, the ulnar bursa, becomes inflamed, this can compress the median nerve in the canal, leading to pain and weakness in the hand. None of the other structures mentioned in the question are contained in the carpal tunnel, so they would not be compressed in that space. Q: The point of insertion of the flexor digitorum superficialis tendon to the index finger is on the: A: middle phalanx The flexor digitorum superficialis tendon inserts on the middle phalanx of fingers 2-5; the flexor digitorum profundus tendon inserts on the base of the distal phalanx of fingers 2-5. Both muscles flex the metacarpophalangeal and proximal interphalangeal joints, but flexor digitorum profundus is the only muscle that flexes the distal interphalangeal joints. Q: Structures within the carpal tunnel include: A: Radial bursa The flexor retinaculum spans between the carpal bones to make the carpal tunnel. The contents of the carpal tunnel are: the tendons of flexor digitorum superficialis and flexor digitorum profundus (all contained in the ulnar bursa); the tendon of flexor pollicis longus (contained in the radial bursa) and the median nerve. So, the radial bursa is the only listed structure that is found in the carpal tunnel. The ulnar nerve is superficial to the flexor retinaculum - it's not in the carpal tunnel. The palmar aponeurosis and superficial palmar arterial arch are found on the superficial surface of the palm of the hand--they are not structures found at the wrist. Adductor pollicis is a muscle in the adductorinterosseous compartment of the hand - it is not found near the wrist.

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Anterior and Medial Thigh Q: The femoral canal contains the: A: Deep inguinal lymph node(s) The femoral canal usually contains a deep inguinal lymph node, called the gland or node of Cloquet. This canal opens to the abdominal cavity through the femoral ring, so it might be the site of a femoral hernia. The femoral artery and vein are enclosed in the femoral sheath with the femoral canal, but they are not in the femoral canal. The femoral nerve is also in the femoral triangle, but it is not enclosed by the femoral sheath. It is the most lateral structure in the femoral triangle. The ilioinguinal nerve is not really part of the anatomy of this region. It innervates muscles of the lower abdominal wall and is associated with the superficial inguinal ring. Make sure to remember the difference between the femoral canal and femoral sheath! Q: Which structure does NOT enter or leave the inguinal region by passing deep to the inguinal ligament? A: round ligament of the uterus The round ligament of the uterus travels through the inguinal canal, superior to the inguinal ligament. It eventually leaves the canal through the superficial ring, enters the perineum, and terminates in the labia majora. So, it is never passing deep to the inguinal ligament. The femoral nerve, artery, and vein all travel deep to the inguinal ligament to enter the femoral triangle. The psoas major also travels deep to the inguinal ligament. It then joins with the iliacus to form the iliopsoas, which inserts on the lesser trochanter of the femur via the iliopsoas tendon. Q: When walking, the action of the iliopsoas muscle results in what motion at the hip joint? A: flexion The iliopsoas is a combination of the iliacus muscle and the psoas major which inserts on the lesser trochanter of the femur. It is the most powerful hip flexor. Other hip flexors include sartorius, rectus femoris, and pectineus. These muscles are in the anterior compartment of the thigh, with the exception of pectineus (medial compartment). The abductor muscles are in the lateral compartment of the thigh. They include gluteus medius and minimus, tensor fasciae latae, piriformis, and obturator internus. Adductor longus, brevis, and magnus are muscles in the medial compartment which adduct the hip. The major hip extenders are the hamstrings--semimembranosus, semitendinosus, and biceps femoris. They are in the posterior compartment. Gluteus maximus, in the lateral compartment, is also an important muscle for powerfully extending the hip. Finally, the adductors and gluteus medius, minimus, and tensor fasciae latae are the medial rotators of the thigh. Q: The pulse of the femoral artery is best felt at which superficial reference point? A: femoral triangle The femoral artery passes through the femoral triangle. It lies between the femoral nerve on its lateral side and the femoral vein on its medial side. This is where you would take the femoral pulse. Anterior to the ankle joint, you can feel for the pulse of the dorsalis pedis artery. In the popliteal fossa, you can feel for the pulse of the popliteal artery. (Although, this can be somewhat difficult since the popliteal artery is deep to the popliteal nerve and vein.) Q: What anterior thigh muscle must be retracted to expose the adductor canal and its contents? A: Sartorius

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Sartorius is the roof of the adductor canal. If it was retracted, the contents of the adductor canal would be exposed. The structures contained in the adductor canal are: the femoral artery, femoral vein, saphenous nerve, and nerve to vastus medialis. Adductor longus and magnus make the posterior boundary of the canal, and vastus medialis is the lateral boundary of the canal. Q: Which of the following is NOT located within the adductor canal? A: Deep femoral artery The adductor canal contains: the femoral artery, femoral vein, saphenous nerve, and nerve to vastus medialis. Adductor longus and magnus make the posterior boundary of the canal, and vastus medialis is the lateral boundary of the canal. The roof of the canal is formed by sartorius. The deep femoral artery branches from the femoral artery in the femoral triangle; it then travels deep in the thigh, posterior to adductor longus. So, it is deep to the canal. The deep femoral artery supplies blood to the posterior compartment of the thigh through perforating branches. Q: Inability to extend the knee and loss of cutaneous sensation over the anterior surface of the thigh would indicate a lesion or compression of the: A: Femoral nerve The femoral nerve innervates the quadriceps, which are the muscles that extend the knee. It also provides cutaneous innervation to the anterior thigh and medial leg. This means that the symptoms here fit with an injury to the femoral nerve. The superior gluteal nerve supplies gluteus minimus and medius--two muscles that are important abductors of the hip. These muscles stabilize the pelvis when walking. The lateral femoral cutaneous nerve is a sensory nerve only--if this nerve was injured, the patient would have a loss of sensation over the lateral thigh but no motor weakness. The sciatic nerve is found in the posterior thigh--it does not innervate any muscles directly, but its branches are the common fibular and tibial nerve. If the sciatic was damaged and these two branches were lost, there would be severe motor and sensory deficits throughout the posterior thigh and the leg and foot. The obturator nerve innervates the medial compartment of the thigh--an injury to this nerve would cause weakness in adduction and medial rotation. Hip, Posterior Thigh, Leg Q: What muscle passes through the lesser sciatic foramen? A: obturator internus Obturator internus leaves the pelvis by passing through the lesser sciatic foramen. It eventually inserts on the greater trochanter of the femur and helps to laterally rotate and abduct the thigh. Piriformis leaves the pelvis through the greater sciatic foramen and also inserts of the greater trochanter of the femur. It helps with the same movements as obturator internus--lateral rotation and abduction of the thigh. The other muscles listed act at the hip, but they are not related to the greater or lesser sciatic foramen. Gluteus minimus originates on the ilium and inserts on the greater trochanter of the femur--it abducts and medially rotates the thigh. Quadratus femoris is a lateral rotator of the thigh which originates on the ischial tuberosity and inserts on the quadrate line. Superior gemellus is another lateral rotator of the thigh which inserts with obturator internus on the obturator tendon.

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Q: In order to avoid injury to the sciatic nerve, intramuscular injections should be given in which quadrant of the buttock? A: upper lateral An injection in the posterior hip region is best placed in the upper, outer quadrant of the hip, just inferior and posterior to the anterior superior iliac spine. This is an area where there are not many nerves and vessels that could be injured by the injection. There are several nerves in the posterior hip region that may be injured if intramuscular injections are carelessly placed in the other quadrants of the buttock, including the sciatic nerve, posterior femoral cutaneous nerve, inferior gluteal nerve, and superior gluteal nerve. Q: The femoral artery enters the popliteal fossa (becoming the popliteal artery) by passing through the: A: Adductor hiatus The adductor hiatus is a split in the adductor magnus muscle found at the end of the adductor canal. At the adductor hiatus, the femoral vessels pass through to reach the posterior surface of the leg, changing names to become the popliteal vessels. The femoral triangle is an area in the proximal anteromedial thigh, bounded by the inguinal ligament, sartorius, and the medial edge of adductor longus. It contains the femoral nerve and the three structures covered by the femoral sheath: the femoral artery, vein, and canal. The femoral canal is a structure in the femoral sheath that usually holds a deep inguinal lymph node; it may also be the site of a femoral hernia. The saphenous opening is an opening in the fascia lata where the great saphenous vein passes deep to join the femoral vein. Q: The short head of biceps femoris muscle is innervated by which nerve? A: Common fibular The short head of biceps femoris is innervated by the common fibular nerve; all the other muscles in the hamstring compartment are innervated by the tibial nerve. Both of these nerves are branches of the sciatic nerve. The inferior gluteal nerve innervates gluteus maximus. The obturator nerve innervates the medial, adductor compartment of the thigh. The femoral nerve innervates the muscles of the anterior thigh. Q: The deep femoral artery is the principle blood source for the muscles in which compartment of the thigh? A: Posterior The deep femoral artery supplies the posterior compartment of the thigh with three to four perforating arteries. These arteries pierce adductor magnus and supply blood to the hamstrings--biceps femoris, semitendinosus, and semimembranosus. The anterior compartment of the thigh (the quadriceps) receives blood from the femoral artery. The medial compartment of the thigh receives blood from the obturator artery and medial circumflex femoral artery, as well as the deep femoral. The gluteal region receives blood from the superior and inferior gluteal arteries. Q: A fracture of the ischial tuberosity might be expected to most directly affect the muscles that produce which lower limb movement? A: flexion at the knee The ischial tuberosity is the origin for the hamstrings muscles which are the muscles that allow for extension at the hip and flexion at the knee. If the ischial tuberosity was fractured, the hamstrings would be separated from their origin and would not function properly. The most important hip abductors are gluteus medius and minimus. These muscles are most commonly damaged by an injury to the superior gluteal nerve. The hip adductors are adductor

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longus, brevis and magnus, which insert on the linea aspera of the femur and are innervated by the obturator nerve. The muscles responsible for extending the knee are the quadriceps. They take origin from the surface of the femur and the anterior inferior iliac spine (rectus femoris). The quadriceps are innervated by the femoral nerve. Finally, the hip flexors are rectus femoris (from the quadriceps), pectineus, iliopsoas, and sartorius. These muscles have diverse origins, and are mostly innervated by the femoral nerve. Q: The medial thigh muscles rotate the femur medially, counterbalanced by muscles of the _____________ thigh, including the ___________ muscle, which rotates the femur laterally. A: Lateral; piriformis A good way to answer this question is to look for a muscle that is a lateral rotator of the thigh and then make sure that the compartment that it is listed with is correct. Piriformis laterally rotates the thigh; it is a member of the lateral compartment which includes other muscles that laterally rotate the thigh, like obturator internus and the superior and inferior gemellus muscles. So, this is the best answer. Tensor fasciae latae is in the lateral compartment, but it's a medial rotator of the thigh, so this is not a correct answer. Rectus femoris is one of the quadriceps muscles, found in the anterior compartment of the thigh. This compartment extends the knee and flexes the hip, but these muscles do not rotate the thigh. Biceps femoris is a muscle in the posterior compartment--it's a hamstring muscle that extends the hip and flexes the knee. Q: The hamstrings muscles are supplied by branches of which artery? A: Deep femoral The deep femoral artery supplies the posterior compartment of the thigh with three to four perforating arteries. These arteries pierce adductor magnus and supply blood to the hamstrings--biceps femoris, semitendinosus, and semimembranosus. The fibular artery is a branch of the posterior tibial artery which supplies the muscles and fascia of the lateral leg and ankle. The obturator artery comes from the anterior division of the internal iliac artery; it delivers blood to the medial thigh and hip. The internal pudendal artery is the major source of blood to the perineum. The superficial femoral artery is the name used clinically for the femoral artery after the deep femoral is given off. Therefore, the short segment of femoral artery proximal to the deep/superficial division is sometimes called the common femoral. Q: Of the branches of the internal iliac artery, the one exiting from the greater sciatic foramen superior to the piriformis muscle is the: A: Superior gluteal artery Piriformis is the key to the posterior thigh, and there are many important nerves and arteries that exit the greater sciatic foramen and enter the posterior thigh either above or below piriformis. The superior gluteal artery and nerve are 2 structures that travel through the greater sciatic foramen superior to piriformis. There are many structures that travel through the greater sciatic foramen inferior to piriformis and lie in the posterior thigh. From medial to lateral, these structures are: pudendal nerve, nerve to obturator internus, nerve to quadratus femoris, inferior gluteal artery, posterior femoral cutaneous nerve, inferior gluteal nerve, and sciatic nerve. See Netter plates 502 and 503 for a picture. You should know what nerves and vessels are superior and inferior to piriformis! None of the other arteries mentioned travel superior to piriformis to reach the posterior thigh. The iliolumbar artery is a branch of the posterior division of the internal iliac. It travels on the posterior body wall to supply blood to the iliacus, psoas major, and quadratus lumborum. The internal pudendal artery is a branch from the anterior division of the internal iliac artery. It leaves the pelvis with the inferior gluteal artery, traveling inferior to piriformis. It enters the perineum through the lesser sciatic foramen to supply muscles, skin, and the erectile bodies there. Finally, the lateral sacral arteries are branches of the posterior division of the internal iliac artery--they are on the posterior body wall

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and they supply the sacrum, sacral nerve rootlets, meninges, and the nearby muscles. Q: A patient complains of localized pain in a swollen lower calf and cannot strongly plantar flex his foot. What tendon may have ruptured? A: calcaneal Gastrocnemius and soleus insert on the calcaneus via the calcaneal tendon, a tendon of the lower calf which is the thickest and strongest tendon of the body. These muscles are important plantarflexors of the foot, so it is likely that the tendon connected to these muscles has been damaged. The other tendons/muscles listed and their actions are as follows: Fibularis teritus: everts the foot; flexor digitorum longus: flexes toes 2-5; flexor hallucis longus: flexes toe 1; tibialis anterior: inverts and dorsiflexes the foot. Since none of these actions is disrupted, the other tendons are probably fine. Q: A football player tears his calcaneal tendon. You would expect to find weakness in: A: Plantarflexion of the foot The calcaneal tendon is the thickest and strongest tendon of the body. It is the tendon that gastrocnemius and soleus--the major plantarflexors of the posterior compartment--use to insert on the dorsum of calcaneus. So, if this tendon was ruptured, gastrocnemius and soleus would not be inserting on the calcaneus, and the football player would be unable to plantarflex his leg. Dorsiflexion would be impaired if there was damage to the anterior compartment of the leg. Specifically, an injury to tibialis anterior or the deep fibular nerve would lead to a weakness in dorsiflexion. Eversion would be impared if there was an injury to the fibularis muscles--fibularis tertius, fibularis longus, and fibularis brevis--which are all responsible for everting the foot. Inversion would be impaired if there was damage to tibialis anterior and tibialis posterior. These are the two muscles which invert the foot. And remember--extending the knee is done by the quadriceps muscles in the anterior thigh. They are innervated by the femoral nerve, so an injury to this nerve or to the quadriceps muscles themselves might impair extension at the knee. Anterior Leg and Foot Q: The lateral plantar nerve is a branch of which nerve? A: Tibial nerve The lateral and medial plantar nerves are both branches of the tibial nerve. These branches continue to the plantar surface of the foot, innervating the muscles on the plantar surface of the foot and providing cutaneous innervation to the skin of the sole. The deep fibular nerve innervates the anterior compartment of the leg, the muscles on the dorsum of the foot, and provides sensory innervation to the web of skin between the first and second toe. The femoral nerve innervates the anterior (quadriceps) compartment of the thigh, which allows for extension at the knee. The saphenous nerve is a branch of the femoral nerve that travels with the great saphenous vein; it provides cutaneous innervation to the skin of the medial side of the leg and medial side of the foot. The sural nerve is a cutaneous nerve that provides sensory innervation to the skin of the posterior surface of the lower leg and the skin of the lateral side of the foot.

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Q: The most usual site for feeling the pulsations of the dorsalis pedis artery in the foot is: A: Just lateral to the tendon of extensor hallucius longus muscle The dorsalis pedis artery is the continuation of the anterior tibial artery which continues on to the dorsum of the foot. The name change from anterior tibial to dorsalis pedis occurs at the level of the ankle. As the artery crosses into the foot, it lies just lateral to the tendon of extensor hallucis longus, so that's where you would feel a pulse. See Netter Plate 513 for a picture. The pulse of the posterior tibial artery, which comes from the posterior compartment of the leg, might be felt behind the medial malleolus. The pulse of the fibular artery might be felt behind the lateral malleolus, but that pulse would be very weak. There are no special pulses associated with the tendon of fibularis tertius or the second dorsal metatarsal space. Joints of upper and lower limbs Q: The shoulder is most often dislocated in which direction? A: Anterior The shoulder is covered by the muscles of the rotator cuff--subscapularis inserts on the lesser tubercle of the humerus, and supraspinatus, infraspinatus and teres minor insert on the greater tubercle of the humerus. This set of muscles provides support on the superior, anterior, and posterior sides of the shoulder joint. There are no muscles supporting the inferior aspect of the shoulder joint. However, despite the subscapularis muscle and the glenohumeral bands, most shoulder dislocations still occur in the anteroinferior direction, with the humeral head dislocating forward and downward. Q: Which of the following structures is unique to a synovial joint? A: joint cavity The joint cavity, or synovial cavity, is the one structure that is unique to a synovial joint. This cavity is lined by a synovial membrane or articular cartilage and supported by a joint capsule or capsu lar ligament. The synovial membrane is made of vascular connective tissue which produces synovial fluid that fills the joint cavity. Accessory and collateral ligaments, bursae, and fibrocartilage may be found at synovial joints, but they are not unique to synovial joints. Q: Which ligament limits extension at the hip joint? A: Iliofemoral The iliofemoral ligament is a Y-shaped ligament extending from the anterior inferior iliac spine to the anterior surface of the intertrochanteric line of the femur. It prevents hyperextension of the hip joint during standing by screwing the femoral head into the acetabulum. (The ischiofemoral ligament also helps to prevent hyperextension of the hip joint by screwing the femoral head into the acetabulum.) Ligamentum capitis femoris attaches the head of the femur to the acetabular fossa. The pubofemoral ligament connects the pubic portion of the rim of the bony acetabulum to the medial surface of the femoral neck. It prevents overabduction of the hip joint. Zona orbicularis is a band of circularly oriented ligamentous fibers that reinforce the capsule of the hip joint--it helps keep the head of the femur in its socket.

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Abdominal Wall Q: The inferior border of the rectus sheath posteriorly is called the: A: arcuate line The rectus sheath is a tough, tendinous sheath over the rectus abdominis muscle. It covers the entire anterior surface of the rectus abdominis. However, on the posterior side of the muscle, the sheath is incomplete-- it ends inferiorly at the arcuate line. Below the arcuate line, the rectus abdominis is covered by transversalis fascia, not the rectus sheath! The linea alba is also related to the rectus abdominis--it is a ligament that runs down the middle of the abdomen, bisecting the rectus abdominis. It is made by the intermingling of the aponeuroses of the external oblique, internal oblique, and transversus abdominis. It's a good place to make a vertical incision. All of the other answer choices are related to the inguinal canal. The falx inguinalis (sometimes called the inguinal falx or conjoint tendon), is the inferomedial attachment of transversus abdominis with some fibers of internal abdominal oblique--it contributes to the posterior wall of the inguinal canal. The inguinal ligament is the ligament that connects the anterior superior iliac spine with the pubic tubercle--it makes the floor of the inguinal canal. The internal (deep) inguinal ring is the entrance to the inguinal canal, where the transversalis fascia pouches out and creates an opening through which structures can leave the abdominal cavity. Q: The posterior layer of the rectus sheath ends inferiorly at the A: Arcuate line The arcuate line is an anatomical feature on the inner surface of the abdominal wall. It is the point at which the posterior lamina of the rectus sheath ends and transversalis fascia lines the inner surface of rectus abdominis. The intercrestal line is an imaginary line drawn in the horizontal plane at the upper margin of the iliac crests. It is a landmark used to find the L4 vertebra, which is useful when performing a spinal tap. Linea alba is an aponeurotic band on the midline of the anterior abdominal wall, which extends from the xiphoid process to the pubic symphysis. It is formed by the combined abdominal muscle aponeuroses, and it provides a useful site for a midline incision in the abdomen. The pectineal line is a structural feature of the pubic bone. It is an oblique ridge on the lateral part of the superior ramus. Finally, the semilunar line is the lateral margin of the rectus abdominis, formed by the fused aponeuroses of the abdominal wall muscles at the lateral margin of the rectus sheath.

Q: Surgical approaches to the abdomen sometimes necessitate a midline incision between the two rectus sheaths, i.e., through the: A: Linea alba The linea alba is an aponeurotic band on the midline of the anterior abdominal wall, which extends from the xiphoid process to the pubic symphysis. It is formed by the combined abdominal muscle aponeuroses. Because there are no major arteries or nerves running in the linea alba, it provides a useful site for a midline incision in the abdomen. The linea aspera is a vertical ridge on posterior surface of the femur. The arcuate line is the point at which the posterior lamina of the rectus sheath ends, and transversalis fascia lines the inner surface of rectus abdominis. The semilunar line is the lateral margin of the rectus abdominus, formed by the fused aponeuroses of the abdominal wall muscles. The iliopectineal line is a line on the pelvic bones, formed by the arcuate line of the ilium and the pectineal line of the pubis. (Note--the arcuate line of the ilium is totally different than the arcuate line of the rectus sheath!) This line is important because it marks the boundary between the abdominal cavity and the pelvic cavity.

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Inguinal Region Q: Which structure passes through the deep inguinal ring? A: round ligament of the uterus The round ligament of the uterus passes through the deep inguinal ring and runs through the inguinal canal. It is a derivative of the gubernaculum, a structure which pulled the gonads into place during embryonic development. In males, the scrotal ligament is what remains from the gubernaculum. Also keep in mind that, in males, the spermatic cord passes through the deep inguinal ring. Of the other answer choices, the ilioinguinal nerve is the only other one that courses through the inguinal canal. Remember--it leaves through the superficial ring and gives off the anterior labial or scrotal branch as a cutaneous continuation. However, the ilioinguinal nerve does not pass through the deep ring - it enters the inguinal canal on the side. The iliohypogastric nerves run between the internal oblique and transversus abdominis in the abdominal wall, piercing the internal oblique at the anterior superior iliac spine to travel deep to just the external oblique. The inferior epigastric artery runs between the transversus abdominis and the peritoneum, forming the lateral umbilical fold. The medial umbilical ligament is the obliterated umbilical artery--it lies within the medial umbilical fold of peritoneum. Q: The boundaries of the inguinal triangle include all except: A: Arcuate line The inguinal triangle is the site for direct inguinal hernias. It is defined medially by the lateral border of rectus abdominus, inferiorly by the inguinal ligament, and superiorly by the inferior epigastric artery Q: The superficial inguinal ring is an opening in which structure? A: External abdominal oblique aponeurosis The superficial inguinal ring is a slit-like opening between the diagonal fibers of the external abdominal oblique. It is bounded by the medial and lateral crus, and it forms the exit of the inguinal canal. The falx inguinalis is composed of arching fibers of the internal abdominal oblique and the transversus abdominis. It forms the roof of the inguial canal, and the posterior wall medially where it inserts as the conjoint tendon (onto the pubic crest and medial part of the pectineal ligament. Scarpa's fascia is the membranous layer of subcutaneous fascia. Finally, transversalis fascia is found laterally on the posterior wall of the inguinal canal, forming the area of weak fascia in that wall. Q: If a hernia enters into the scrotum, it is most likely a(n): A: Indirect inguinal hernia Indirect inguinal hernias cross through the deep inguinal ring, passing deep to the internal spermatic fascia. This means that they can enter the scrotum fairly easily, and indirect inguinal hernias are often found in the scrotum. Direct inguinal hernias are not covered by the internal spermatic fascia; they enter the inguinal canal next to the spermatic cord, and rarely enter the scrotum. (However, direct inguinal hernias can enter the scrotum on rare occasion, so don't assume that you are dealing with an indirect inguinal hernia just because it has entered the scrotum.) A femoral hernia is protrusion of abdominal viscera through the femoral ring into the femoral canal. It appears as a mass in the femoral triangle, inferolateral to the pubic tubercle. An obturator hernia is a protrusion of a loop of bowel through the obturator canal.

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Q: Which nerve passes through the superficial inguinal ring and may therefore be endangered during inguinal hernia repair? A: Ilioinguinal The ilioinguinal nerve enters the inguinal canal from the side (instead of passing through the deep inguinal ring). It leaves the inguinal canal by passing through the superficial inguinal ring to exit the canal, so it might be injured during inguinal hernia repair. The femoral branch of the genitofemoral nerve travels lateral to the superficial inguinal ring. The iliohypogastric nerve and the subcostal nerve travel superior to the inguinal canal and superficial inguinal ring. Finally, the obturator nerve is a branch of the lumbar plexus which innervates muscles in the thigh. To reach the thigh, this nerve travels deep to the inguinal canal, and it is not involved with this region. Peritoneal Cavity and intestines Q: Which of the following veins does not run a course parallel to the artery of the same name? A: inferior mesenteric The inferior mesenteric vein and inferior mesenteric artery do not run in tandem. The inferior mesenteric vein is part of the portal venous system--it drains into the splenic vein which drains into the hepatic portal vein. The inferior mesenteric artery is a branch off the descending aorta at the level of the L3 vertebral body. However, the inferior mesenteric artery and vein supply/drain the same region: the descending and sigmoid colon and the rectum. The superior epigastric vessels run together and are the continuation of the internal thoracic artery and vein. The superficial circumflex iliac vessels run together in the superficial fat of the abdominal wall. The superior rectal vessels are the terminal ends of the inferior mesenteric vessels, found on the superior surface of the rectum. The ileocolic artery and vein are branches off the superior mesenteric vessels. They are both running in the mesentery, supplying/draining the cecum, appendix, and terminal portion of the ileum. Q: Meckel's diverticulum: A: a site of ectopic pancreatic tissue Meckel's diverticulum is an out-pouching of the small bowel that is present in 2% of the people and usually occurs about 2 feet before the junction with the cecum. It can be lined by the mucosa of the stomach and ulcerate. Or, it can be lined with ectopic pancreatic tissue. An abnormal persistence of the urachus is called a urachal fistula. Since the urachus is attached to the bladder, this can be detected if yellow fluid (urine) is seen coming from the umbilicus of a newborn. A failure of the midgut loop to return to the abdominal cavity is called an omphalocele. In this instance, the midgut remains in the body stalk, where it had left the gut to rotate. Polyhydramnios is an excess production of amniotic fluid , often caused by anencephaly or an esophageal fistula. The other conditions will be covered more in embryology - for now, focus on Meckel's diverticulum. Q: The artery of the midgut is the: A: Superior mesenteric The superior mesenteric artery is the artery of the midgut. The celiac trunk is the artery of the foregut, and the inferior mesenteric arery is the artery of the hindgut. The splenic artery is a branch of the celiac artery, and the proper hepatic artery is a branch of the common hepatic artery, which is a branch of the celiac artery.

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Stomach and Spleen Q: Which of the following structures does not lie at least partially in the retroperitoneum? A: spleen The spleen is the only organ listed which is covered entirely by visceral peritoneum. About the other organs... The kidney and suprarenal glands are retroperitoneal organs. This is different than the secondarily retroperitoneal organs that started out in a mesentery and then got pushed against the posterior wall. The kidneys and the suprarenal glands began developing in the retroperitoneum and stayed there. The duodenum and pancreas are partially peritonealized and partially retroperitoneal. The first two centimeters of the superior duodenum is peritonealized, but the rest of the duodenum, until the duodenojejunal junction, is retroperitoneal. For the most part, the pancreas is secondarily retroperitoneal, although the tail of the pancreas is peritonealized, lying within the splenorenal ligament. Q: The spleen contacts all of the following organs EXCEPT: A: jejunum The spleen is not in contact with the jejunum. The jejunum lies medial and inferior to the spleen. The kidney is in contact with the posteromedial surface of the spleen. The left colic flexure is in contact with the inferomedial surface of the spleen. The tail of the pancreas touches the hilum of the spleen. The stomach is in contact with the anteromedial surface of the spleen. See Netter Plate 289 for a picture of the different impressions on the spleen. Q: Which is not a boundary of the epiploic (omental) foramen? A: Aorta The epiploic (omental) foramen is a passageway between the greater peritoneal sac and the lesser peritoneal sac. It is located posterior to the hepatoduodenal ligament and the first part of the duodenum. The caudate lobe of the liver forms the posterior wall of the epiploic foramen. The aorta is retroperiteoneal, and it does not form a boundary of this foramen. Q: Which of the following is NOT in contact with the spleen? A: Duodenum The duodenum is not in contact with the spleen. The inferior portion of the spleen contacts the left colic flexure. The superior portion of the spleen contacts the diaphragm--the spleen is convexly curved to fit the concavity of the diaphragm. The tail of the pancreas inserts into the hilum of the spleen. The stomach contacts the anteriomedial portion of the spleen. You should really know what organs contact the spleen and where these organs contact the spleen! Q: The fundus of the stomach receives its arterial supply from the: A: Splenic As it enters the hilum of the spleen, the splenic artery gives off short gastric arteries which supply blood to the fundus of the stomach. These short gastric arteries travel in the gastrosplenic ligament to reach the fundus. The common hepatic artery does not directly supply the stomach--it gives off the gastroduodenal artery, which supplies the right portion of the greater curvature of the stomach with the right gastro-omental artery. The inferior phrenic artery is a branch of the aorta which supplies blood to the diaphragm. The left gastro-omental artery is a branch of the splenic artery which supplies the left half of the greater curvature. The right gastric artery is a branch of the

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proper hepatic artery which supplies the right half of the lesser curvature. See Netter Plate 290 to get a good picture of these arteries and their areas of distribution. Duodenum, liver, pancreas, gallbladder Q: Which organ becomes retroperitoneal during rotation of the gut tube? A: duodenum This question is asking you to identify the organ that is secondarily retroperitoneal. This means that it started out peritonealized but became pressed against the posterior body wall and stuck there during development. Except for the first few centimeters of the superior segment and the duodenojejunal junction, the duodenum is a secondarily retroperitoneal organ - it used to have a mesentery, but that was lost during gut rotation. Although the kidney is a retroperitoneal organ, it is not secondarily retroperitoneal - it started developing in the retroperitoneum and stayed there. The spleen, stomach, and transverse colon are all peritonealized. What segments of the colon are peritonealized? The cecum, transverse colon, and the sigmoid colon are peritoneal, but the ascending and descending colon are retroperitoneal. Q: The division between the true right and left lobes (internal lobes) of the liver may be visualized on the outside of the liver as a plane passing through the: A: gallbladder fossa and inferior vena cava This question is asking you to identify the structures that make the line that separates the true/functional lobes of the liver. The concept of functional lobes contrasts with traditional anatomical terminology, which separated the liver into the left, right, quadrate and caudate lobes. These traditional lobes were based on anatomical appearance, while the functional lobes are based on the distribution of the portal vein, hepatic arteries, and hepatic bile ducts. The functional lobes of the liver are separated into a right and left lobe by the gallbladder fossa and the inferior vena cava. So, the old "right lobe" corresponds to the functional right lobe, while the caudate, quadrate, and left lobes under anatomical terminology are lumped together as one big left lobe. Q: The inferior mesenteric vein usually joins which vein? A: Splenic The inferior mesenteric vein usually empties into the splenic vein. The splenic vein and the superior mesenteric vein then unite to form the portal vein. Look at Netter Plate 290 for a picture of this. Remember--the inferior vena cava and left renal vein are caval veins--they are not involved in draining the gut. Kidneys and retroperitoneum Q: The vagus nerve passes into the abdomen by passing through the A: Esophageal hiatus Remember back to the thorax--the vagus joins the esophageal plexus and covers the esophagus. The anterior and posterior vagal trunks form from the esophageal plexus-- they pass into the abdomen through the esophageal hiatus, on the anterior and posterior surfaces of the esophagus. The aortic hiatus is deep to the median arcuate ligament--it transmits the aorta and the thoracic duct. The caval foramen is found in the central tendon of the diaphragm; it transmits the inferior vena cava. Psoas major is deep to the medial arcuate ligament, and quadratus lumborum is deep to the lateral arcuate ligament.

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Q: The pararenal fat in the kidney bed is an elaboration of: A: Extraperitoneal connective tissue Each kidney is embedded in two layers of fat, with a membrane (the renal fascia), in between the layers. Inside the renal fascia, and directly atop the kidney, is the perirenal fat. Outside the renal fascia, you will find the pararenal fat, which is an elaboration of extraperitoneal connective tissue. Although the kidney is not peritonealized, the peritoneum from the posterior body wall lies over the anterior surface of the pararenal fat. The kidney is not a secondarily retroperitoneal organ--it began development in the retroperitoneum. So, it does not have a fusion fascia. Q: The cisterna chyli accompanies which structure as it passes through the diaphragm? A: Aorta In 25-50% of cases, the inferior portion of the thoracic duct includes a dilated portion called the cisterna chyli. When present, all of the lymph trunks draining the abdomen and lower limbs dump into it, as well as the most inferior intercostal lymph trunks. When it is not present, these trunks simply empty into the thoracic duct. So, the cisterna chyli is a portion of the thoracic duct, and the thoracic duct passes through the diaphragm with the aorta at the T12 level. The inferior vena cava passes through the central tendon of the diaphragm at the T8 level. The esophagus and vagal branches pass through the right crus of the diaphragm at the T10 level. The greater thoracic splanchnic nerves pass through the fibers of the left and right crus. Q: The nerves of the lumbar plexus are arranged around specific muscles of the posterior abdominal wall. Which of these nerves lies immediately medial to the psoas major muscle? A: Obturator The obturator nerve lies along the medial border of the psoas major muscle. The femoral nerve lies along the lateral border of the psoas major muscle, between psoas major and iliacus. The genitofemoral nerve pierces psoas major then lies on top of that muscle. The ilioinguinal nerve emerges at the lateral border of psoas major, then travels laterally. Thoracic Wall, Pleura, Pericardium Q: The second costal cartilage can be located by palpating the: A: sternal angle The sternal angle is the point where the costal cartilage attaches the second rib to the sternum. This is an important anatomical landmark to remember--it is used to find the valves when auscultating the heart! The costal margins are formed by the medial borders of the 7th through 10th costal cartilages. They are easily palpable and extend inferolaterally from the xiphisternal joint. The sternal notch/jugular notch is the notch located at the superior border of the manubrium, between the sternal ends of the clavicles. The sternoclavicular joints are simply the joints connecting the sternum with the clavicles. Finally, the xiphoid process is the bone that makes the inferior part of the sternum. Q: The thoracic wall is innervated by: A: intercostal nerves Intercostal nerves are the ventral primary rami of spinal nerves T1-T11. They provide motor innervation to intercostal muscles, abdominal wall muscles (via T7-T11) and muscles of the forearm and hand (via T1). They provide

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sensory innervation to the skin of the chest and abdomen on the anterior and lateral sides. The other nerves listed do not innervate the chest wall. Dorsal primary rami provide motor innervation to true back muscles and sensory innervation to the skin on the back. The lateral pectoral nerve provides motor innervation to pectoralis major only, while the medial pectoral nerve provides motor innervation to pectoralis major and minor. The thoracodorsal nerve provides motor innervation to latissimus dorsi. Q: The sternocostal surface of the heart is formed primarily by the anterior wall of which heart chamber? A: right ventricle The heart has three important surfaces: an anterior surface, a diaphragmatic surface, and a pulmonary surface. The anterior surface, or sternocostal surface, is mostly made up of the right ventricle. The diaphragmatic surface is mostly the left ventricle, but a little bit of the right ventricle sits on the diaphragm as well. Finally, the pulmonary surface, which is on the left, is mostly made up of the left ventricle. Q: The first rib articulates with the sternum in close proximity to the: A: sternoclavicular joint The first rib articulates with the sternum directly below the sternoclavicular joint. The nipple is found in the fourth intercostal space, between the 4th and 5th ribs. The sternal angle is connected to the costal cartilage of rib 2. Finally, the xiphoid process is located just below the point where the costal cartilage of rib 7 articulates with the sternum. The root of the lung consists of the main bronchus, pulmonary and bronchial vessels, lymphatic vessels, and nerves entering and leaving the lung. Q: The portion of the parietal pleura that extends above the first rib is called the : A: cupola The cupola is the cervical parietal pleura which extends slightly above the level of the 1st rib into the root of the neck. The costodiaphragmatic recess is the part of the pleural sac where the costal pleura changes into the diaphragmatic pleura. It is the lowest extent of the pleural sac. The costomediastinal recess is found where the costal pleura becomes the mediastinal pleura. Endothoracic fascia is connective tissue between the inner chest wall and costal parietal pleura. The costocervical recess is a made up term. Q: A needle inserted into the 9th intercostal space along the midaxillary line would enter which space? A: Costodiaphragmatic recess The costodiaphragmatic recess is the lowest extent of the pleural cavity or sac. It is the part of the pleural sac where the costal pleura changes into the diaphragmatic pleura. It is also the area into which a needle is inserted for thoracocentesis, and it is found at different levels at different areas of the thorax. At the mid clavicular line, the costodiaphragmatic recess is between ribs 6 and 8; at the midaxillary line it is between 8 and 10; and at the paravertebral line it is between 10 and 12. So, inserting the needle just above the 9th rib at the midaxillary line should put you in the costodiaphragmatic recess. The cardiac notch is a structure on the left lung which separates the lingula below from the upper portion of the superior lobe of left lung. The costomediastinal recess is found where the costal pleura becomes the mediastinal pleura. The cupola is the part of the pleural cavity which extends above the level of the 1st rib into the root of the neck. The oblique pericardial sinus is an area of the pericardial cavity located behind the left atrium of the heart.

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Q: The pleural cavity near the cardiac notch is known as the: A: Costomediastinal recess The costomediastinal recess is an area right next to the cardiac notch, which is an indentation in the superior lobe of the left lung. If you take a very deep breath, the lingula of the left lung, which is formed by the cardiac notch, will tend to expand into the costomediastinal recess. The costodiaphragmatic recess is the lowest extent of the pleural cavity or sac. It is the part of the pleural sac where the costal pleura changes into the diaphragmatic pleura. The cupola is the part of the pleural cavity which extends above the level of the 1st rib into the root of the neck. The hilum is found on the medial surface of the lung--it is the point at which the structures forming the root enter and leave the lung. The pulmonary ligament is a fold of pleura located below the root of the lung, where the visceral pleura and the mediastinal parietal pleura are continuous with each other. Q: The ductus arteriosus sometimes remains open after birth requiring surgical closure. When placing a clamp on the ductus, care must be taken to avoid injury to what important structure immediately dorsal to it? A: Left recurrent laryngeal nerve The left recurrent laryngeal nerve is a branch of the vagus that wraps around the aorta, posterior to the ductus arteriosus or ligamentum arteriosum. It then travels superiorly to innervate muscles of the larynx. It's important to protect this nerve during surgery! If the left recurrent laryngeal nerve becomes paralyzed, a patient might experience a hoarse voice or even have difficulty breathing due to a laryngeal spasm. You should make sure that you understand what this nerve does, what types of procedures might injure this nerve, and the effects of a damaged left recurrent laryngeal! The accessory hemiazygos vein is a vein on the left side of the body. It drains the posterolateral chest wall and empties blood into the azygos vein. The left internal thoracic artery is a branch of the left subclavian artery that supplies blood to the anterior thoracic wall. The left phrenic nerve runs lateral to the vagus nerve and its branches in the thorax; it is not close enough to be damaged by the surgery. The thoracic duct is deep in the chest - it travels between the azygos vein and the aorta, posterior to the esophagus. Q: The sternal angle is a landmark for locating the level of the: A: Second costal cartilage he sternal angle is a very important anatomical landmark which is used when placing the stethoscope and listening for heart sounds. The sternal angle is the location of the attachment of the costal cartilage of the second rib to the sternum. So, once you locate the sternal angle on a patient, you know the location of the second rib, and you can use that landmark to find the right spots to auscultate each valve of the heart. Also remember that a horizontal plane through the sternal angle passes through the T4/T5 intervertebral disc and marks the inferior boundary of the superior mediastinum.

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Heart Q: Blockage of which of the following arteries would lead to ischemia of the apex of the heart? A: Anterior interventricular (descending) The anterior interventricular artery is a branch of the left coronary artery. It supplies both ventricles as well as the interventricular septum. It also reaches the apex, supplying that area as well. The left circumflex artery is the other major branch of the left coronary artery. It supplies the posterior surface of the left ventricle, but does not reach the apex of the heart. The right coronary artery has two major branches: the right marginal and the posterior interventricular artery. (The right coronary also gives off two smaller branches to the SA node and the AV node.) The right marginal artery supplies the right ventricle, while the posterior IV artery supplies the interventricular septum and the two ventricles. Neither of these arteries provides a major source of blood to the apex of the heart. Q: A stethoscope placed over the left second intercostal space just lateral to the sternum would be best positioned to detect sounds associated with which heart valve? A: pulmonary The best place to listen to heart valves is not at their actual sternocostal projections. If you place your stethoscope exactly where a valve is located, you may not hear anything because the valve might be deep in the chest or the sound might be muffled by bone or cartilage. Instead, you want to listen to the valves by putting your stethescope at a point downstream from the valve where you can hear the blood flowing and colliding with the muscular chest wall. There are points of auscultation for all four heart valves: Pulmonic: left second intercostal space, lateral to the sternal angle; Aortic: right second intercostal space, lateral to the sternal angle; Mitral: left fifth intercostal space, 8cm away from the midline; Tricuspid: left fourth intercostal space, just lateral to the sternum. Learn these points of auscultation very well, because you will be using them again and again! Q: Which valves would be open during ventricular systole? A: Aortic and pulmonary Remember that ventricular systole is the period when the ventricles are contracting. This contraction forces blood out of the heart, which pushes the aortic and pulmonary valves open. During systole, the tricuspid and mitral valves are closed. They are prevented from prolapsing (being pushed back into the atrium) by the chordae tendinae and papillary muscles. Q: Which chamber's anterior wall forms most of the sternocostal surface of the heart? A: right ventricle The heart has three important surfaces: an anterior surface, a diaphragmatic surface, and a pulmonary surface. The anterior surface, or sternocostal surface, is mostly made up of the right ventricle. The diaphragmatic surface is mostly the left ventricle, but a little bit of the right ventricle sits on the diaphragm as well. Finally, the pulmonary surface, which is on the left, is mostly made up of the left ventricle.

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Q: The heart sound associated with the mitral valve is best heard: A: In the 5th left intercostal space The four valves of the heart can be auscultated at very distinct spaces. The mitral valve can be ausculatated in the left 5th intercostal space, slightly below the nipple.The aortic valve can be ausculatated in the 2nd right intercostal space, just lateral to sternal angle. The pulmonary valve can be auscultated in the 2nd left intercostal space, just lateral to sternal angle. The tricuspid valve can be auscultated in the 4th left intercostal space, just lateral to sternum. Q: The sound associated with tricuspid stenosis (narrowing) in a 40-year-old male would be best heard at which location on the anterior chest wall? A: xiphoid area, just off the sternum It's best to listen to sounds associated with the tricuspid valve at the fourth left intercostal space, just lateral to the sternum. The answer that comes the closest to this is E. What would you hear in the other spaces? Below the left nipple, in the fifth intercostal space, you would be auscultating the mitral valve. This is also the valve that you can hear at the apex of the heart. The right 2nd intercostal space near the sternum is the site for auscultating the aortic valve. Finally, it would be difficult to hear anything over the sternal angle, since the stethoscope would be over bone, which would blunt any sounds! Q: Which structure does NOT lie in the coronary sulcus? A: right marginal artery The coronary sulcus is the groove which separates the atria from the ventricles. The right and left coronary arteries, circumflex artery, and coronary sinus all lie in this groove. The right marginal artery is a branch of the right coronary artery which lies on the right ventricle and supplies that chamber of the heart. Q: Which structure contains postganglionic sympathetic fibers? A: ulnar nerve When a nerve fiber reaches the sympathetic chain, there are three things that can happen. First, the nerve fibers can enter a ganglia, synapse at that level, and rejoin the spinal nerve via the grey ramus communicans. Second, the preganglionic nerve fibers can travel up or down the trunk, synapse in a ganglia at another level, and then rejoin a spinal nerve. This is how sympathetic fibers join spinal nerves at the cervical and lumbar levels, which are above and below the lateral horn. Third, some preganglionic fibers do not synapse in the trunk and, instead, form splanchnic nerves. These nerves descend into the abdomen and synapse in other ganglia. The greater thoracic splanchnic nerve contains preganglionic fibers that are destined to synapse in the celiac plexus. The recurrent laryngeal nerve provides motor and sensory innervation to the upper esophagus and pharynx. Finally, the vagus nerve is a mixed nerve that carries preganglionic parasympathetic fibers. None of these nerves carry postganglionic sympathetic fibers. The ulnar nerve innervates muscles of the hand, arm, and provides some sensory innervation to skin of the hand and arm. It is derived from ventral rami of spinal nerves, all of which carry postganglionic sympathetic fibers (for vascular smooth muscle, arrector pili muscles, and sweat glands).

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Q: While listening to a patient's heart sounds with a stethoscope, you identify a high-pitched sound in the second right intercostal space, just lateral to the edge of the sternum. Your correct conclusion is that you have detected stenosis of which heart valve? A: Aortic The four valves of the heart can be auscultated at very distinct spaces. The aortic valve, which separates the left ventricle from the aorta, can be auscultated in the 2nd right intercostal space, just lateral to sternal angle. Since this is the space where the murmur is heard, the problem must be with the aortic valve. The mitral valve, which separates the left atrium from the left ventricle, can be auscultated in the left 5th intercostal space, slightly below the nipple. The pulmonary valve, which separates the right ventricle from the pulmonary artery, can be auscultated in the 2nd left intercostal space, just lateral to sternal angle. The tricuspid valve, which separates the right atrium from the right ventricle, can be auscultated in the 4th left intercostal space, just lateral to sternum. Q: Which feature is found only in the left lung? A: cardiac notch The cardiac notch is only found on the left lung, which makes sense since the heart is located on the left side of the mediastinum. The horizontal fissure is a deep groove that separates the middle lobe from the upper lobe of the right lung. The left lung does not have a horizontal fissure. The oblique fissure is found in both lungs. It separates the upper lobe from the lower lobe in both lungs and the middle lobe from the lower lobe in the right lung. Both lungs also have a superior lobar bronchus leading to their superior lobes. Finally, the right lung has three lobes while the left lung has two lobes. Q: Which statement is true about the right lung? A: its upper lobar bronchus lies behind and above the right pulmonary artery

The structures at the root of the lung have different relationships in the right and left lungs. On both sides, the pulmonary veins are anterior and inferior while the bronchus is posterior. The difference between the two sides involves the pulmonary arteries. On the right side, the arteries are anterior to the bronchus, while on the left side the arteries are superior to the bronchus. The right lung is slightly larger than the left lung, and the lingula is found in the left lung only. Neither lung is in the mediastinum--the mediastinum is the space between the two pleural sacs. Finally, the phrenic nerve passes anterior to the root of the lung--on both the left and right sides. Q: Which vessel courses across the mediastinum in an almost horizontal fashion? A: left brachiocephalic vein The left brachiocephalic vein joins with the right brachiocephalic vein to form the superior vena cava on the right side of the body. So, the left brachiocephalic vein must course across the mediastinum to reach its destination. The left subclavian artery and vein are lateral to the mediastinum, while the left jugular and common carotid travel vertically.

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Posterior Mediastinum Q: The aorta is located in which mediastinal compartment(s)? A: middle and posterior The ascending aorta is located in the middle mediastinum, along with the other great vessels. The aortic arch is located in the lowest part of the superior mediastinum (its lower border lies at the level of the sternal angle). The descending aorta is in the posterior mediastinum. Remember what's in what part of the mediastinum--it's important! Q: Most of the drainage of the thoracic body wall reaches the superior vena cava via the azygos vein. A notable exception is the left superior intercostal vein, which normally drains into the: A: Left brachiocephalic vein The left superior intercostal vein drains intercostal spaces 2-4, and then drains into the left brachiocephalic vein. See Netter Plate 231 for a picture of this relationship. The left bronchial vein is a small vein that removes venous blood from the lungs--it drains into the accessory hemiazygos vein. The left pulmonary veins carry oxygenated blood from the lung to the left atrium of the heart. The left subclavian vein is a continuation of the left brachiocephalic vein--this vein drains blood from the arm into the left brachiocephalic vein. The superior vena cava is formed by the junction of the left and right brachiocephalic veins; it delivers blood to the right atrium. Pelvis and Pelvic Viscera Q: The part of the uterine wall which is not shed during menstruation is the: A: myometrium This question is phrased in a slightly tricky way, so it's important to break it down before looking at the answers. There are two things to think about here. First, you need to decide if a structure is part of the uterus. If it is part of the uterus, then you need to decide if it is shed during menstruation. The correct answer will be a structure that is part of the uterus but is not shed during menstruation. Answers about structures that are not shed during menstruation because they are not part of the uterine wall are incorrect. The myometrium is our correct answer. It is the middle muscular component of the uterine wall and it is not shed during menstruation. The endometrium is the inner mucosal coat of the uterus. It exhibits many characteristic changes during the menstrual cycle and all but its stratum basalis is shed during menstruation. The mesometrium is the mesentary of the uterus which forms the major part of the broad ligament of the uterus. It is not even part of the uterine wall, so it's not the answer to look for. Cervical mucosa lines the cervix, which is the inferior portion of the uterus. This mucosa is shed during menstruation. Finally, the uterus does not have rugae - rugae are the folds found in the lining of the vagina (and stomach). Q: The extension of the vaginal lumen around the intravaginal part of the uterine cervix is the: A: fornix The cervix is the inferior end of the uterus that projects into the vagina. This means that the vagina comes up and wraps around the cervix, creating the vaginal fornix. There are multiple fornices at the top of the vagina: anterior, posterior, and lateral. The cervical canal is the passageway through the cervix to the vagina. The uterine lumen is the hollow center of the uterus. The rectouterine and uterovesicular pouches are two peritoneal folds found in the pelvic cavity. The rectouterine pouch is a peritoneal fold extending across the floor of the pelvic cavity from the sacrum (beside the rectum) to the uterus. The uterovesicular pouch is a peritoneal fold extending from the uterus to the bladder.

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Q: Under normal conditions, fertilization occurs in which part of the female reproductive tract? A: ampulla of the uterine tube Fertilization normally takes place in the ampulla of the uterine tube. This is the middle segment of the uterine tube, and it is the longest and widest segment. The infundibulum is the funnel-shaped distal end of the uterine tube, and the isthmus is the narrowest part of the uterine tube which connects directly to the uterus. The uterine lumen is the site of implantation, not fertilization. Finally, the cervical canal is the pathway out of the uterus at its inferior end-- it would not be an appropriate site for fertilization or implantation. Q: Which structure does NOT form part of the boundary defining the trigone of the bladder? A: urachus The trigone of the bladder is bounded by the openings of the left and right ureteric orifices superolaterally, the interureteric crest between the openings of the ureters and the internal urethral orifice inferiorly. The urachus is the structure that joins the apex of the fetal bladder to the umbilicus. After birth, it becomes the median umbilical ligament. Q: Which of the following is considered a part of the broad ligament? A: mesovarium The mesovarium, mesometrium, and mesosalpinx are the three peritoneal sections that create the broad ligament. The mesosalpinx covers the uterine tube and hangs below it to meet with the mesovarium. The mesovarium covers the ovary and ovarian ligament. It extends posteriorly from the mesosalpinx like a shelf. The mesometrium makes up the rest of the broad ligament. The ovarian ligament is located in the broad ligament but is not part of the broad ligament. It is a round cord that attaches the ovary to the uterus just below the point where the uterine tube enters the uterus. The round ligament of the uterus reaches the lateral surface of the uterus below the uterine tube. It is continuous with the ovarian ligament and it holds the fundus of the uterus forward. The suspensory ligaments of the ovary are peritoneal folds that cover the ovarian neurovascular supply as these vessels pass over the pelvic brim to reach the ovary. Finally, the uterosacral ligament connects the isthmus of the uterus to the sacrum. It is important for the support of the uterus, and it is found in the rectouterine fold. Q: Which of the following does not conduct spermatozoa? A: duct of the seminal vesicle The duct of the seminal vesicle carries seminal fluid, a basic fluid containing fructose. The contents of the seminal fluid buffers the acid in the vagina and provides nutrients for sperm. The duct of the seminal vesicle joins with the ampulla of the ductus deferens (which is carying sperm) to form the ejaculatory duct. This is the first place where seminal fluid mixes with sperm. Sperm is first formed in the seminiferous tubules. They then travel from the head to the tail of the epididymis, through the ductus deferens, into the ejaculatory duct where they mix with seminal fluid, into the prostatic urethra, through the rest of the urethra, and then out the penis. So, all of the other answer choices are places that are important for the passage of sperm. Q: The most inferior extent of the peritoneal cavity in the female is the: A: rectouterine pouch

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Remember: The rectouterine and vesicouterine pouches are the two pouches created by draping the peritoneum over the pelvic organs. These pouches are the two lowest extents of the peritoneal cavity, so to answer this question, you  just need to decide wh ich one goes lower. Since th e uterus is folded ov er the bladder, the rec touterine pouch can extend to a slightly lower level than the vesicouterine pouch, which makes C the correct answer. The pararectal fossa is formed by lateral reflections of perineum over the superior one third of the rectum; this space gives the rectum room to fill with feces. The paravesicular fossa is a space near the bladder that allows the bladder to expand. Why is the rectovesicular pouch incorrect? It's only found in males, not females! (But, if the question had asked about males, the rectovesicular pouch would have been the correct answer.) Q: The prostate gland: A: Encircles the urethra; Is extraperitoneal There are two true statements here. First, the prostate gland encircles the urethra. It circles around the first part of the urethra, the prostatic urethra. This is why urinary retention is one symptom of prostatic hypertrophy--if the prostate is enlarged, it may close around the urethra, occluding this passage and preventing urine from exiting the bladder. The prostate gland is also extraperitoneal. Remember: the rectovesicular pouch, a fold of peritoneum that hangs between the bladder and rectum, is the lowest extent of the peritoneal cavity in males . But, the prostate is found on the posterior side of the bladder, below the point where the peritoneal membrane created this fold. So, it is an extraperitoneal organ. The lobes of the prostate are: anterior, posterior, lateral, and middle. Finally, the prostate would not be imaged using an intravenous urogram. In an intravenous urogram, a patient is given IV contrast, and radiographic images are taken as the contrast is excreted, passing through the kidneys, ureters, and bladder. Since the prostate is not part of this excretory pathway, it would not be viewed through this method. Q: The part of the broad ligament giving attachment and support to the uterine tube is the: A: Mesosalpinx The mesosalpinx is the part of broad ligament that supports the uterine tube. The mesosalpinx extends inferiorly to meet the root of the mesovarium; it attaches the uterine tube to the mesometrium. The mesometrium is the part of the broad ligament below the junction of the mesosalpinx and the mesovarium; it attaches the body of the uterus to the pelvic wall. The mesovarium is the part of broad ligament that forms a shelf-like fold supporting the ovary--it attaches the ovary to the mesometrium and mesosalpinx. The round ligament of the uterus is a connective tissue band that attaches to the inner aspect of the labium majus and the uterus. It is found in the broad ligament, and it traverses the inguinal canal. Q: Which structure is NOT found within the true pelvis? A: femoral nerve To answer this question, you need to understand what the true pelvis is. The true pelvis is the area beneath the pelvic brim (pelvic inlet), where the pelvic viscera are located. The false pelvis is the area above the pelvic brim, bounded by the iliac blades. Now, you just need to think about the structures listed and determine which ones are in which location. The femoral nerve is the structure that is not in the true pelvis. After coming off the lumbar plexus with contributions from L2, 3, and 4, the femoral nerve runs along the border between the psoas major muscle and the iliacus to travel into the lower limb. It never descends below the pelvic brim, so it is not in the true pelvis. Hypogastric nerves connect the superior and inferior hypogastric plexuses. Since the inferior hypogastric plexus is lying between the pelvic viscera and the pelvis wall, in the true pelvis, the hypogastric nerves should also be in the true pelvis. The internal pudendal artery is a branch of the anterior division of the internal iliac artery. It lies in the true pelvis and supplies blood to the perineum. The obturator artery is a branch of the anterior internal iliac artery or, if it is the aberrant obturator, the inferior epigastric artery. It is in the true pelvis, and exits the pelvis through the obturator foramen. The pelvic splanchnic nerves represent the sacral portion of the craniosacral outflow

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(parasympathetic) of the autonomic nervous system. They come from the ventral rami of the second, third, and fourth sacral nerves. So, that puts them in the true pelvis, too. Q: A structure which takes the form of a hood anterosuperior to the clitoris: A: prepuce The prepuce is a fold of smooth skin that extends over the glans clitoris. It is formed by the joining of the anterior divisions of the labia minora. The frenulum of the clitoris is a small fold found posterior to the clitoris. It is formed by the joining of deeper, posterior, divisions of the labia minora. The labia majora are fat-filled elevations of skin lying on each side of the vestibule of the vagina. The labia minora are smaller folds of skin lying medial to the labia majora. They extend posteriorly and inferiorly from the clitoris. Q: A structure which is homologous to the male scrotum: A: labia majora The labia majora and scrotum are homologous structures. The labia minora is the female counterpart of the pentscrotal raphe. The glans of the clitoris and glans of the penis are homologous structures. Finally, the shaft of the corpus cavernosum in the female is the shaft of the clitoris, which is homologous to the shaft of the penis. Q: The male pelvis tends to differ from the female pelvis in that the male pelvis often has a: A: Smaller subpubic angle There are four major differences between the male and female pelvis. First, the subpubic angle and pubic arch are greater in the female pelvis than in the male pelvis. This is why B is correct-- the male pelvis has a smaller subpubic angle than the female pelvis. A second difference between the female and male pelvis is that the pelvic inlet for females is rounded, while for males it is heart shaped. Third, the pelvic outlet for females is larger than in males. Finally, the female pelvis has iliac wings that are more flared than in males. Q: The rectouterine pouch is the lowest extent of the female peritoneal cavity. At its lowest, it provides a coat of peritoneum to a portion of the: A: Vagina In females, the rectouterine pouch is a peritoneal fold reflecting from the rectum to the posterior fornix of the vagina. At its lowest extent, the rectouterine fold is draped over the posterior fornix of the vagina. This means that surgeons can make an incision in the posterior fornix of the vagina and enter the rectouterine pouch to harvest eggs from the ovaries or remove an ectopic pregnancy. Take a look at Netter Plate 337 for a picture of this relationship. Pelvic Neurovasculature Q: Preganglionic parasympathetic nerve fibers within the pelvic (inferior hypogastric) plexus arise from S2, 3, 4 and enter the plexus via: A: pelvic splanchnic nerves Pelvic splanchnic nerves carry parasympathetic fibers from the lateral horn of the spinal cord at the S2, 3, and 4 levels. They can be seen coming off of the ventral primary rami of S2, 3, and 4 and going to the inferior hypogastric plexus. These nerves provide parasympathetic innervation to the pelvic viscera and the GI tract distal to

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the left colic flexure. (Remember, the vagus gives parasympathetic innervation to the rest of the gut.) Sacral splanchnic nerves come off the sacral sympathetic chain ganglia, carrying sympathetic fibers that will go to the inferior hypogastric plexus. To remember the difference between the pelvic and sacral splanchnics, just remember that the sacral splanchnics are named after a spinal cord segment, just like the thoracic, lumbar, and cervical splanchnics that you know and love. These all carry sympathetic fibers. Pelvic splanchnics are not named after a spinal cord segment and they're different--they carry parasympathetic fibers. The grey rami communicantes are structures that postganglionic sympathetic neurons travel on to get out of the sympathetic trunk and rejoin a spinal nerve. There are gray rami in the pelvis. The white rami communicantes are structures that preganglionic sympathetic fibers use to get out of a spinal nerve to enter the sympathetic trunk. White rami are seen between the T1 to L2 levels, but not in the pelvis. Finally, the hypogastric nerves carry postganglionic sympathetic nerves from the superior hypogastric plexus to the inferior hypogastric plexus. Q: Blood supply to the superior portions of the bladder typically arises from the ____________ arteries. A: Umbilical The umbilical artery supplies the superior part of the bladder by giving off the superior vesical arteries. In males, this artery supplies the ductus deferens via the artery of the ductus deferens. Distal to those branches, the umbilical artery is not patent, and it becomes the medial umbilical ligament. The middle rectal artery supplies blood to the middle of the rectum, while the obturator artery supplies blood to the medial thigh and hip. The inferior gluteal artery supplies blood to gluteus maximus, and the uterine artery supplies blood to the uterus. Perineum and external Genitalia Q: The boundaries of the perineum include all the following except: A: sacrospinal ligament The sacrospinal ligament connects the sacrum to the ischial spine. Together with the sacrotuberous ligament, it converts the greater and lesser sciatic notches into greater and lesser sciatic foramina. However, it is not near the perineum--it is more important as a landmark that creates the greater and lesser sciatic foramina which helps to organize the structures exiting the pelvis. The bounderies of the perineum are as follows. Anterior: pubic symphysis; Anterolateral: ischiopubic rami; Lateral: ischial tuberosities; Posterolateral: sacrotuberous ligament; Posterior: tip of the coccyx. These boundaries create two triangles in the perineum: the urogenital triangle and the anal triangle. The urogenital triangle is the anterior subdivision, bounded by the pubic symphysis, ischiopubic rami, and the posterior margin of the perineal membrane, which corresponds to an imaginary line between the two ischial tuberosities. The anal triangle is the posterior division of the perineum. It starts off where the urogenital triangle ends: at the posterior margin of the perineal membrane. Then, it is bounded by the sacrotuberous ligament and the tip of the coccyx. It's important to look at these triangles and orient yourself to them using the bones in your bone set--you'll realize that the perineum is not contained in one flat plane; instead, the triangles are at angles to each other. Q: A condensation of fibrous tissue in the female located at the center of the posterior border of the perineal membrane is the: A: perineal body The perineal body is an irregular fibromuscular mass located at the center of the posterior border of the perineal membrane. It is the site where many muscles converge, including bulbospongiosus, external anal sphincter, and the superficial and deep transverse perineal muscles. This is found only in females; the male homolog for this structure is the central tendinous point.

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Frenulum is a word that refers to a small fold, and there are two in the female perineum, so this isn't even specific enough to be a good answer. The frenulum of the clitoris is a structure lying deep to the clitoris, formed by the deep labia minora. This structure is not near the posterior border of the perineal membrane; it is clearly in the urogenital triangle. There is also a frenulum of the labia minora which is just anterior to the perineal body, also in the urogenital triangle. Although the frenulum of the labia minora is sort of superficial to the center of the posterior border of the perineal membrane, the question is asking for a structure that is closely associated with the perineal membrane. This means that structures of the external genitalia will be wrong answers. The posterior labial commissure is another structure of the external genitalia which is located over the posterior border of the perineal membrane, and it's also a wrong answer for the same reason. The anococcygeal ligament is a ligament that attaches the external anal sphincter to the coccyx. It is located in the anal triangle. The pubovesicular ligament attaches the bladder to the pubic bone. It is more associated with the pelvic viscera as opposed to the perineum. Q: The artery which supplies blood to the major erectile body in both the male and female is the: A: deep artery of the penis/clitoris The deep artery supplies the corpus cavernosum of the penis/clitoris, which is the major erectile body. It is one of the two terminal branches of the internal pudendal artery, with the other one being the dorsal artery of the penis/clitoris. This artery supplies superficial structures. The artery of the bulb supplies blood to the bulb of the penis and the bulb of the vestibule. Although the bulbs are erectile tissue, the corpus cavernosum is the main erectile body. The posterior labial/scrotal artery supplies exactly what you would guess--the posterior labia or scrotum. It is a branch of the perineal artery. Finally, the superficial external pudendal artery supplies the skin and superficial fascia of the upper medial thigh, as well as the skin of the pubic region. It is a superficial branch of the femoral artery. Q: The vestibular bulbs/bulb of the corpus spongiosum are firmly attached to the: A: perineal membrane The bulbs of the vestibule/bulb of the corpus spongiosum are pieces of erectile tissue that attach to the perineal membrane. They are covered by the bulbospongiosis muscle. The ischiopubic rami, pubic symphysis, and ischial tuberosities are bony structures important for defining the boundaries of the perineum. The crura of the corpora cavernosa attach to the ischiopubic rami and the perineal membrane. Q: The part of the male reproductive tract which carries only semen within the prostate gland is the: A: ejaculatory duct The ejaculatory duct is a duct which courses through the prostate gland and contains only semen. Remember, semen is the combination of sperm from the ductus deferens, seminal fluid from the seminal vesicle, and secretions of the prostate gland. The ejaculatory duct is formed by the union of the duct of the seminal vesicle and the ampulla of the ductus deferens, and it is the site where sperm and seminal fluid mix. The prostatic urethra is also contained in the prostate gland, and it carries semen, but it also carries urine out of the bladder. The membranous urethra is the continuation of the prostatic urethra outside of the prostate gland, and it carries both semen and urine as well. The seminal vesicle is a structure on the posterior surface of the bladder that produces seminal fluid. The ductus deferens is a passageway that carries sperm from the epididymis to the ejaculatory duct. Q: The perineum is bounded by all of the following skeletal elements except: A: spine of the ischium The bounderies of the perineum are as follows. Anterior: pubic symphysis; Anterolateral: ischiopubic rami; Lateral: ischial tuberosities; Posterolateral: sacrotuberous ligament; Posterior: tip of the coccyx. The spine of the ischium, which projects into the pelvis toward the lateral pelvic wall, does not make up a boundary of the perineum

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Anterior Triangle of the neck Q: Which muscle is innervated by a branch of the ansa cervicalis? A: sternohyoid The sternohyoid muscle is one of the strap muscles which runs from the manubrium and the sternal end of the clavicle to the hyoid bone. It is innervated by the ansa cervicalis, and it depresses and stabilizes the hyoid bone. Platysma is a muscle of facial expression; it is innervated by the cervical branch of CN VII, the facial nerve. Sternocleidomastoid and trapezius are both innervated by the accessory nerve (CN XI). Sternocleidomastoid receives fibers from C2 and C3 for proprioception, while trapezius receives proprioceptive fibers from C3 and C4. Q: The layer of encircling cervical fascia that splits to enclose sternocleidomastoid and trapezius muscles is the: A: Superficial layer of deep fascia The superficial layer of deep cervical fascia extends between trapezius and sternocleidomastoid in the posterior triangle and between the paired sternocleidomastoid muscles in the anterior triangle. Superficial fascia is the same as subcutaneous tissue--the tissue that you see as you remove the skin. Infrahyoid fascia is the layer of deep fascia that covers the strap muscles in a sheet. Prevertebral fascia is the deep fascia surrounding the vertebral column and the associated muscles (like the scalenes). Finally, the visceral fascia is the fascia that encloses the deep structures of the neck, including the thyroid, the larynx and trachea, and the esophagus. The anterior part of that fascia is the pretracheal fascia, and the posterior part of the visceral fascia is the buccopharyngeal fascia. To get a better picture of this, see Netter plate 30. Q: Which of the following is a dorsal ramus of a spinal nerve? A: greater occipital nerve The greater occipital nerve is the cutaneous branch of the dorsal primary ramus of spinal nerve C2 - it provides cutaneous innervation to the posterior scalp. The other nerves listed are all nerves from the cervical plexus, which is formed by ventral primary rami C1-C4. The supraclavicular nerves come from C3 and C4 in the cervical plexus. These cutaneous nerves provide sensory innervation to the skin of the root of the neck, upper chest, and upper shoulder. The great auricular nerve comes from C2 and C3 branches; it provides sensory innervation to the ear and the skin below the ear. The lesser occipital nerve comes from C2 only - it innervates the skin behind the ear. The transverse cervical nerve is also a cutaneous branch from the cervical plexus--from C2 and C3, providing sensory innervation to the skin of the neck anteriorly. Q: Which of the following is true of the inferior thyroid arteries? A: They often supply all four parathyroid glands The inferior thyroid arteries are branches of the thyrocervical trunk. (The superior thyroid arteries are branches of the external carotid artery.) The inferior thyroid arteries are closely associated with the middle cervical sympathetic ganglia and supply the inferior poles of the thyroid. They are found on the posterior surface of the thyroid gland, which is where the parathyroid glands are located. So, they are the primary source of blood for the four parathyroid glands. Q: These structures are all located in the superficial fascia of the neck EXCEPT A: Omohyoid muscle

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The omohyoid muscle is a muscle found in the anterior and posterior triangle of the neck. It depresses and stabilizes the hyoid bone. Like all muscles (except the muscles of facial expression), the omohyoid is not found in the superficial fascia. The external jugular vein is a small vein found in the superficial tissue on the lateral side of the neck. The platysma is a muscle of facial expression that draws down the corners of the mouth and depresses the mandible. It inserts into the skin, so it is found in the superficial fascia. The cervical branch of the facial nerve, which innervates the platysma, is also in the superficial fascia. Finally, the transverse cervical nerve is a branch of the cervical plexus that innervates the skin of the anterior neck. Because it is providing cutaneous innervation, it is found in the superficial fascia. Q: The superior belly of the omohyoid forms the anterior border of which cervical triangle? A: Carotid The carotid triangle is bounded anteriorly by the superior belly of the omohyoid muscle, laterally by the sternocleidomastoid, and superiorly by the posterior belly of the digastric. The carotid vessels and carotid sheath can be found in this triangle. The muscular triangle is bounded by the midline as its medial border, the superior belly of the omohyoid as its superolateral border, and sternocleidomastoid as its inferolateral border. The strap muscles, thyroid, and parathyroids are found in this triangle. The omoclavicular triangle, in the posterior neck, is bounded superiorly by the inferior belly of the omohyoid muscle, anteriorly by the sternocleidomastoid muscle, and inferiorly by the clavicle. The third part of the subclavian artery and the subclavian vein are located in this triangle. The posterior triangle of the neck is bounded anteriorly by the sternocleidomastoid muscle, posteriorly by trapezius, and inferiorly by the clavicle. The submandibular triangle is bounded anteriorly by the anterior belly of the digastric, posteriorly by the posterior belly of the digastric, and superiorly by the lower border of the mandible. It contains the superficial portion of the submandibular gland and the facial artery and vein. Q: The cervical plexus innervates all of the following structures EXCEPT: A: Platysma is a muscle of facial expression. It inserts into the skin and helps lower the angle of the mouth and depress the mandible. It is innervated by the cervical branch of the facial nerve (CN VII). All of the other muscles or areas of skin are innervated by branches of the cervical plexus, a plexus made of the ventral primary rami of the C1C4 spinal nerves. The diaphragm is innervated by the phrenic nerve, which is made from the C3, C4 and C5 ventral primary rami. The omohyoid muscle is innervated by ansa cervicalis, a motor branch of the cervical plexus. The skin over the thyroid cartilage is innervated by the transverse cervical nerve, a cutaneous sensory nerve from C2 and C3 roots of the cervical plexus. The skin over the clavicle is innervated by other cutaneous sensory nerves from the C3 and C4 roots of the cervical plexus--the supraclavicular nerves. Q: Which of the following statements about the cervical plexus is true? A: The cervical plexus consists solely of the ventral primary rami of spinal nerves C1-C4. It supplies cutaneous innervation through nerves like the lesser occipital, great auricular, supraclavicular and transverse cervical. It also supplies motor innervation to the strap muscles through the ansa cervicalis. So, it has a motor and sensory component. It does not innervate the platysma--platysma is a muscle of facial expression innervated by the cervical branch of the facial nerve (CN VII). Posterior Triangle of the Neck Q: Which statement is true of the internal jugular vein? A: It is accompanied by the deep cervical chain of lymph nodes he deep cervical chain of lymph nodes runs closely with the internal jugular vein. The internal jugular vein does not drain all of the thyroid gland--the superior and middle thyroid veins drain into the internal jugular vein, but the inferior thyroid veins drain directly into the brachiocephalic veins. The internal jugular vein does not drain into the

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external jugular vein. The external jugular vein is a smaller vein on the lateral neck which drains into the subclavian vein. The internal jugular vein meets the subclavian vein, and the two vessels join to form the brachiocephalic vein. The prevertebral fascia is found deep in the neck, over the vertebrae and the prevertebral muscles. So, the internal  jugular vein is very su perficial to this f ascia. Finally, the sternocleidomastoid muscle crosses over the internal jugular vein. Q: Which structure lies immediately anterior to the right anterior scalene muscle at its costal attachment? A: Subclavian vein The subclavian vein lies anterior to the right and left anterior scalene muscles. It can be found coursing over the anterior scalene muscles on both the right and left sides. The subclavian arteries lie posterior to the anterior scalene muscles--they travel between the anterior and middle scalenes on both sides of the neck. The thoracic duct is found on the left side only--it would not be on the right side of the neck. On the left side, the thoracic duct enters the left brachiocephalic vein where it is formed by the union of the subclavian and internal jugular veins. So, the thoracic duct does contact the anterior scalene muscle, but only on the left side of the neck. The thyrocervical trunk is a branch of the first part of the subclavian artery, medial to the anterior scalene. It is not in contact with the anterior scalene. Finally, the vagus nerve travels with the carotid vessels in the carotid sheath. It is anterior to the anterior scalene, but not in immediate contact with the muscle. This means that subclavian vein is the best answer. Q: Which of the following hyoid muscles is an important landmark in both the anterior and posterior triangles of the neck? A: omohyoid The omohyoid muscle is an important landmark in both the anterior and posterior triangles of the neck. In the anterior triangle, the superior belly of the omohyoid muscle serves as the superolateral border of the muscular triangle and the anterior border of the carotid triangle. In the posterior triangle, the inferior belly of the omohyoid muscle divides the omoclavicular triangle from the occipital triangle. So, in both the anterior and posterior triangles, the omohyoid is an important muscle that subdivides the triangles. All of the other listed muscles are associated with the anterior triangle only. Geniohyoid runs from the hyoid bone to the genu of the mandible-- it is a deep muscle on the floor of the mouth. It is found deep to the submental triangle. Mylohyoid is another muscle associated with the floor of the mouth--it is in the submandibular triangle and the submental triangle. Sternohyoid is a strap muscle -- it is in the muscular triangle. Finally, stylohyoid is a small muscle innervated by the facial nerve which retracts and elevates the hyoid. It is found in the submandibular triangle. Carotid Sheath, Pharynx, Larynx Q: In performing a thyroidectomy, caution should be exercised when ligating (tying) the inferior thyroid artery, as it lies in a very close relationship to which nerve? A: recurrent laryngeal The recurrent laryngeal nerve crosses the inferior thyroid artery near the lower lobe of the thyroid. This means that the recurrent laryngeal nerve would be at risk in any surgery involving the inferior thyroid artery or the inferior poles of the thyroid. The recurrent laryngeal nerve becomes the inferior laryngeal nerve at the inferior border of cricopharyngeus, and this nerve continues on to innervate all the muscles of the larynx with the exception of cricothyroid. So, you really need to take care to protect the recurrent laryngeal nerve--injuring this structure could lead to hoarseness, permanent loss of voice, or even death due to a laryngeal spasm. None of the other listed nerves are related to the inferior thyroid artery. Ansa cervicalis is a branch of the cervical plexus which hangs in front of the internal jugular vein. It innervates the strap muscles. The hypoglossal nerve

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winds behind the internal jugular vein, then sweeps around lateral to the carotid vessels and into the floor of the mouth, where it innervates the tongue muscles. The phrenic nerve lies on top of the anterior scalene muscles--it then travels through the thorax to innervate the diaphragm. Finally, the vagus is found in the carotid sheath--it is associated with the common carotid and the internal carotid arteries. Q: The carotid body is innervated by a branch of the: A: Glossopharyngeal nerve (CN IX)

The carotid body is innervated by the carotid branch of the glossopharyngeal nerve. It is a small, reddish-brown ovoid mass that lies on the medial side of the carotid bifurcation, serving as a chemoreceptor that monitors the level of carbon dioxide in the blood. The hypoglossal nerve (CN XII) innervates the muscles of the tongue. The spinal accessory nerve is a motor nerve that innervates the sternocleidomastoid and the trapezius. The sympathetic trunk provides sympathetic innervation to the head and neck. Finally, the vagus nerve supplies motor innervation to the muscles of the pharynx and larynx, with the exception of stylopharyngeus, and the muscles of the palate, with the exception of tensor veli palatini. Q: The "danger zone" of the scalp is recognized as which of the following layers? A: loose connective tissue The scalp is comprised of the following layers, from superficial to deep: Skin, Connective tissue, Aponeurosis, Loose connective tissue, and Pericranium. If you take the first letter of each, it spells SCALP. So, now that you know the order of the layers, you need to figure out which one is the danger zone--the place where infections can spread very quickly. And that layer is layer 4, the loose connective tissue. Pus or blood can spread easily in this layer, and infections in this layer can pass into the cranial cavity through emissary veins. So, infections in the loose connective tissue can pass into intracranial structures such as the brain and meninges. Although layer 2 is a connective tissue layer, too, this layer is a bit thicker and is not a place where infections can easily spread. Q: An infection in which scalp layer is likely to spread most readily? A: loose areolar tissue Loose areolar tissue is another name for the loose connective tissue layer of the scalp. Pus or blood can spread easily in this layer, and infections in this layer can pass into the cranial cavity through emissary veins. So, infections in the loose connective tissue can pass into intracranial structures such as the brain and meninges. This can also be called the "danger layer" of the scalp. Remember--the scalp is comprised of the following layers, from superficial to deep: Skin, Connective tissue, Aponeurosis, Loose connective tissue, and Pericranium. (SCALP!) Although layer 2 is a connective tissue layer, too, this layer is a bit thicker and is not a place where infections can easily spread. Q: The glossopharyngeal nerve exits the skull via what opening? A: Jugular foramen The glossopharyngeal nerve (CN IX), vagus (CN X) and accessory nerve (CN XI) exit the skull at the  jugular foramen. The posterior meningeal artery enters the skull through this space. The mandibular division of the trigeminal nerve (V 3) exits the skull through foramen ovale. The carotid canal is the place where the internal carotid artery and the internal carotid nerve plexus enter the skull. The hypoglossal canal is where the hypoglossal nerve (CN XII) leaves the skull. The stylomastoid foramen is the hole that the facial nerve (CN VII) uses to exit the skull.

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Parotid Gland and Face Q: Which nerve provides motor innervation to the buccinator muscle? A: buccal branches of VII The buccal branches of the facial nerve provide motor innervation to the buccinator muscle. Remember, these buccal branches of the facial nerve are motor nerves only--they do not do any sensory innervation. Don't mix this nerve up with the buccal nerve, which is a branch of the mandibular division of the trigeminal nerve (V 3)! The buccal nerve is a sensory nerve only--it does not innervate any muscles; it only gives sensory innervation to the skin of the cheek and the mucosal lining of the cheek. The auriculotemporal nerve is also part of the mandibular division of the trigeminal nerve--it carries the postganglionic parasympathetic fibers to the parotid gland and provides sensory innervation to the skin of the anterosuperior ear, part of the external auditory meatus, and the temporomandibular  joint. The marginal mand ibular nerve is anothe r branch of the facial nerve--it innervates the muscles of facial expression on the lower lip and chin. Q: Which nerve provides cutaneous innervation to the skin of the angle of the mandible? A: great auricular nerve The great auricular nerve is a branch of the cervical plexus that provides cutaneous innervation to the skin of the ear and skin below the ear, including the angle of the mandible. The auriculotemporal nerve is a branch of the mandibular division of the trigeminal nerve (V3) with two important functions. First, it carries postganglionic parasympathetic fibers to the parotid gland. Second, the auriculotemporal nerve provides sensory innervation to the skin of anterosuperior ear, part of the external auditory meatus, and the temporomandibular joint. The lesser petrosal nerve is not a sensory nerve--it is a branch of the glossopharyngeal nerve that carries preganglionic fibers to the otic ganglia. Finally, the buccal branches and marginal mandibular branches of the facial nerve are motor nerves only--not sensory nerves! The buccal branches of the facial nerve innervate the buccinator and the other muscles of facial expression above the lip. The marginal mandibular branch innervates the muscles of facial expression of the lower lip and chin. Q: Which nerve carries postganglionic parasympathetic fibers to the parotid gland? A: Auriculotemporal nerve The auriculotemporal nerve is a branch of the mandibular division of the trigeminal nerve (V 3). It has two important functions: First, it carries postganglionic parasympathetic fibers to the parotid gland. These fibers come from the otic ganglia, where they synapsed with the presynaptic fibers from the glossopharyngeal nerve (CN IX). These presynaptic fibers were carried to the otic ganglia by the lesser petrosal nerve. Second, the auriculotemporal nerve provides sensory innervation to the skin of anterosuperior ear, part of the external auditory meatus, and the temporomandibular joint. The great auricular nerve is a sensory nerve from the cervical plexus--it innervates the skin of the ear and the skin below the ear. The marginal mandibular nerve is a branch of the facial nerve--it innervates the muscles of facial expression for the lower lip and chin. Q: A patient is unable to wink; what muscle is affected? A: orbicularis oculi Orbicularis oculi is a muscle of facial expression that closes the eyelid for winking. It is innervated by the temporal and zygomatic branches of the facial nerve. Frontalis is the anterior belly of the epicranius muscle; it elevates the eyebrows and wrinkles the forehead. It is innervated by the temporal branches of the facial nerve (VII). Levator palpebrae superioris elevates the upper eyelid; it is innervated by the oculomotor nerve (III). The superior tarsal muscle