Fracture

 

FRACTURE I. 

Definition   Fracture

-any break in the continuity of the bone. - an interruption or disruption on the normal continuit continuity y of the bone that results from excessive force/stress or pathology that has weakened done.   Open/compound fracture - a fracture where there is a communication with the outside of environment. -the fracture site is communicates with the skin surface   Closed/simple fracture - fracture in which the skins remains in intact and there is no communication between the bone and the outside.

II. 

Related Anatomy

  Bone or osseous tissue- contains an abundant extracellular matrix matrix that

surrounds widely separated cells.   Structure of the bone:

 

  Diaphysis - is the bone’s shaft or bodybody- the long main portion of the bone   Epiphyses - are the proximal and distal ends of the bone   Metaphyses - are the regions between the diaphysis diaph ysis and epiphysis.   Articular cartilage- is a thin layer of hyaline cartilage covering the part

of the epiphysis where the bone forms an articulation. -reduces friction and absorbs shock at freely movable mov able  joints   Periostium- surrounds the external bone in the surface wherever it is not covered by articular cartilage. The periosteum also protects p rotects the bone, assists in fracture repair, helps nourish bone tissue and serves an attachment point for ligaments and tendons.   Medullary cavity or marrow cavity - is a hollow, cylindrical space within the diaphysis that contains fatty yellow bone marrow in adults.   Endosteum- is a thin membrane that lines the internal bone surface facing the medullary cavity.   Developmental of the bone   Membranous/ intramembranosus/mesenchymal or dermal bone

-is the simpler of the two methods of bone formation -formed by direct transformation of condense mesenchyme or primitive connective tissue,   Endochodral / intracartilagenous/cartilage bone - formed by replacing a pre-formed cartilage model. mode l.   Compact bone (substansia compacta)  - contains few spaces and is the

strongest from the bone tissue.    Osteon / harvesian system- functional unit of the bone.   Haversian canal- longitudinal channels.   Volkmann’s canal- transverse or oblique channels interconnecting one

harvesian canal to another.   Lacunae –   – cavities cavities filled with osteocytes that are uniformly spaced throughout the interstitial substance of the bone.   Canaliculi - slender,branching tubular passage interconnecting the lacunae. -essential for nutrition of bone cells.   Spongy bone(substantia spongiosa)

-makes up most of the inferior bone tissue of short, flat and irregularly shaped of the bones and most of the epiphysis of long bones. -composed of lamellae but with thin trabeculae.

 

-absent of harvesian system   Cellular component of bone:

Osteogenic cells  -unspecialized stem cells derived from mesenchyme, the tissue from which

almost all connective tissue are formed. -they are the only bone cells to division. -the resulting cells develop into osteoblast. Osteoblast -are bone-building cells. -responsible for bone formation -they synthesize and secrete the collagen fibers and other organic components needed to build the extracellular matrix of bone tissue. Osteocytes  – mature mature bone cells. -Main cells in the bone tissue and maintain its daily metabolism, such as the

exchange of the nutrients and wastes with the blood. Osteoclast - are huge cells derived from the fusion of as many as 50 monocytes and are concentrated in the endosteum.   Composition of the bone   Hydroxyapatite

-attributes to the hardness of the bone. -compose of the Ca, phosphate and carbonate -an inorganic component 70% of the weight of bone, the rest of which are 20%organic and 10%water   Type I collagen -90% of the organic component of bone. -also found in skin, tendon, blood vessels bone.  

Epidemiology   Clavicular Fracture

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Childhood under 25 years old 8% middle third of clavicle 15% lateral 1/3 of clavicle 5% medial 1/3 of clavicle

 

  6% of fracture involved carpal bones

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70% carpal fracture involve the scaphoid 80% middle third of scaphoid 15% proximal third of scaphoid 4% distal third of scaphoid 1% distal tubercle

  The most fracture site was the distal forearm with a peak in girls and boys at          

11-12 years of age.   Hip fracture: mostly affected are the elderly 60-70 y/o  The sex specific incidence was 43 to 74 for boys and girls respectively with the incident ratio of 1:7   Distal forearm fracture-24% followed by Tibia/fibular shaft 13%  Forearm shaft 11% 

III.  ETIOLOGY    Pathologic fracture

o

-occur in bones weakened by b y preexisting disease such as tumor, cysts, osteomyelitis, or osteoporosis o  Traumatic fracture    Direct- fracture at the site of impact     Indirect- fracture caused by a force transmitted to the bone from some  parts of the body.    Muscular traction- fracture caused by sudden contraction of a muscle.  • Trauma  Trauma  • Motor vehicle accidents  accidents   • Assault  Assault  • Overuse (marathon runners, military); sudden changes in training (duration, intensity) • Participation in sports, including dance (recreational or competitive)  competitive)   • Advanced age  age  • Women: postmenopausal osteoporosis; osteoporosis; military: stress fractures • Men: hypogonadism (erectile (erectile dysfunction, prostate cancer)

IV. 

PATHOPHYSIOLOGY I.  According to completeness   Incomplete   Greenstick fracture- occurs in children, in which the bone is bent and broken only part of the way through its shaft,

 

  Fissured fractured- a mere splint of the bone without displacement

of the bone fragments.   Perforating fracture- (+)hole such as bullets   Depressed- saucer or gutter shaped in which a problem of a bone is driven inward towards the body.     Complete Impacted fracture- broken ends driven into each other Comminuted fracture- bone broken to a several pieces or fragments. Complicated fracture- (+) injury to some organs or important structure near the fracture site site II. 

According to displacement 1.  Transverse fracture- fracture surface is perpendicular to the long axis; caused by angulatory force 2.  Oblique fracture- fracture surface forms an angle with the axis ax is of the shaft. 3.  Spiral fracture- break coils around the bone due to torsional force. 4.  Comminuted fracture   Lateral displacement   Angulated displacement   Overlapped displacement   Rotational displacement

Types of union:   Delayed union 

  occurs fracture fails to consolidate consolidate in the time time required required for union to take

 place   healing process is retarded, however ,forming a firm union is still possible in sufficient length of time Causes: -  -  -  -  -  -  - 

inaccurate reduction –  reduction –  alignment  alignment of fracture inadequate or interrupted immobilization serve local traumatization impairment of bone circulation (+) infection Loss of bone substance Distraction or separation of bone fragments

  Malunion  –   –  union  union in poor position

 

-  Malalignment of fracture site at the time of immobilization -  Mobility of fracture site at the time of immobilization   Non-union –   –  present  present when process of bone repair have h ave ceased after having failed

to form a firm union -   No fracture should be considered ununited until atleast 6 months -  Pseudoarthrosis Pseudoarthrosis –   –  sometimes  sometimes used interchangeably with non –  non  –   union -  Special form of non –  non –  union  union in which bone ends, covered by fibrocartilage, are separated by a cleft or false joint, surrounded by a pseudocapsule than often contains synovial fluid Specific types of fracture:   Jefferson’s  fracture/ Burst fracture of  atlas     burst fracture of ring atlas   MOI: usually a sequelae of another cervical spine injury

  Hangman’s fracture/Traumatic spondylolisthesis  of  axis    MOI: hyperextension and axial compression   Flexion teardrop  fracture 

  Retropulsion of the larger portion of a vertebral body bod y into the spinal canal

detatched from an anterior fragment (teardrop)   Subaxial cervicalspine (C3 –  (C3 –  C7)  C7)   Most severe flexion compression injury   Burst fracture of  spine    fracture of the anterior and middle columns with fragment displaced into neural canal.   Scapular Fracture    Tenderness over the scapular and acromial a cromial region   MOI: direct blow in the shoulder usually after a significant traumatic evident.   Clavicular  fracture  

  Pain in the shoulder region

  May or may not have an obvious deformity.   Majority occur in childhood and adults