Revision: frxs Flashcards
clavicle frx cause, result, who is most at risk, state of acromioclavicular joint
cause: -indirect force from outstretched hand through forearm and arm to shoulder
- fall directly onto shoulder
- during delivery if the baby is broad-shouldered (but the bones usually heal fast)
result: -med frag is pulled up due to sternocleidomastoid muscle
- lat frag drops as trapezius cannot hold the weight of the U/limb -> shoulder drops
- lat frag can also be pulled med by adductor muscles eg pec M.
- due to the subcut position, the end of the superior directed frag is prominent -> palpable a/o apparent
very frequent, esp in children, where it is often incomplete -> greenstick frx -> 1 side of bone is broken and other is bent
the strong coracoclavicular ligament usually prevents disloc of AC joint
cause of clavicle frx
-indirect force from outstretched hand through forearm and arm to shoulder
- fall directly onto shoulder
- during delivery if the baby is broad-shouldered (but the bones usually heal fast)
result of clavicle frx
-med frag is pulled up due to sternocleidomastoid muscle
- lat frag drops as trapezius cannot hold the weight of the U/limb -> shoulder drops
- lat frag can also be pulled med by adductor muscles eg pec M.
- due to the subcut position, the end of the superior directed frag is prominent -> palpable a/o apparent
people most at risk of clavicle frxs
clavicle frxs are very frequent, esp in children, where it is often incomplete -> greenstick frx -> 1 side of bone is broken and other is bent
state of acromioclavicular joint after clavicle frx
the strong coracoclavicular ligament usually prevents disloc of AC joint
scapula frx cause, complications, most common site, treatment
caused by severe trauma eg a pedestrian-vehicle accident
usually also involves frxed ribs
often involves acromion
little treatment is needed as the bone is surrounded by muscle
types of humeral frx
frxs to surgical neck (the most common)
avulsion frx of greater tubercle of humerus
transverse and spiral frx of shaft
intercondylar frx
avulsion frx
fragment of bone tears away from main mass due to physical trauma
frx to surgical neck of humerus cause and result
cause: minor fall onto a hand is transmitted to humerus, esp common in the elderly w/ osteoporosis
result: often 1 fragment is pushed into the spongy bone of the other (impacted frx) -> the site is sometimes stable -> humerus can be moved w/ little pain
axillary nerve injury
impacted frx
one bone is firmly driven into another
avulsion frx of greater tubercle of humerus found most commonly in, cause, result
seen most commonly in middle aged and elderly
cause: usually from a fall onto the acromion, although it can also be due to a fall onto the hand when the arm is abducted
result: subscapularis pulls the humerus into medial rotation
transverse frx of shaft of humerus cause, result, healing
cause: direct blow to arm (fall on outstretched hand leads to spiral frx)
result: deltoid pulls prox frag laterally
healing: as the humerus is surrounded by muscle and a well developed periosteum, it heals well
spiral frx of humeral shaft cause, results in
caused by a fall on outstretched hand, leads to foreshortening
intercondylar frx of humerus cause, result
caused by a severe fall on a flexed elbow
results in the olecranon process being driven like a wedge between the med and lat condyles
radius and ulna injury characteristics, types
characteristics: due to the IO membrane the frx of 1 bone usually leads to the dislocation of the other
- direct injury leads to transverse frx at middle third of bone
- usually is the result of severe injury
types: -Colle’s frx w/ avulsion of ulnar styloid process
- epiphyseal plate injuries
Colle’s frx cause, found most commonly in, result, healing, site, result in ulna
cause: forced dorsiflexion of wrist due to breaking fall w/ hand
found most commonly >50 years old in women (as they are more at risk from osteoporosis)
result: -complete transverse frx of distal 2cm
- distal fragment is displaced dorsally and comminuted (broken to pieces)
- posterior displacement and tilt of distal frag of radius -> DINNER FORK DEFORMITY
- radial angulation of wrist, radial shortening
heals well due to good blood supply
site is distal end of radius
results in avulsion of ulnar styloid
result of Colle’s frx
- complete transverse frx of distal 2cm
- distal fragment is displaced dorsally and comminuted (broken to pieces)
- posterior displacement and tilt of distal frag of radius -> DINNER FORK DEFORMITY
- radial shortening and radial angulation of wrist
- results in avulsion of ulnar styloid
avulsion of ulnar styloid cause
colle’s frx, as the radius no longer projects more distally than the ulna
epiphyseal plate injuries of radius cause, most common in, result
cause: distal radius frx where the frx line extends through dist epiphyseal plate
most commonly found in older children due to freq falls where the force is transmitted from hand to radius and ulna
result: the healing process can lead to malalignment of plate and disturbance of radial growth
scaphoid frx cause, site, diagnosis, healing
cause: fall on palm of abducted hand
site: across narrow part of scaphoid
diagnosis: easily misdiagnosed on x rays as a severely sprained wrist
- however after 10-14 days later x rays show frx due to bone resorption
healing: takes more than 3 months normally due to poor blood supply
- can lead to necrosis of prox scaphoid/degenerative joint disease of wrist, may need to be fused surgically (arthrodesis)
metacarpal frx cause, healing
if only 1 MC is frx then the closely bound other MCs hold it in place
if, due to severe crushing injury to hand, >1 MC is frxed, leads to instability
boxer’s frx is the 5th MC:
cause: head of bone rotates over distal end of shaft leading to flexion deformity from a punch w/ closed hand and abducted wrist
good blood supply leads to quick healing
phalanges frx cause, result
crushing injuries are common and very painful
distal phal: comminuted and haematoma forms (very painful)
middle and prox phals: from crushing/hyperextension
hamate frx result
ulnar nerve and artery damage
non union of frxed bony parts due to traction from muscles
