MSK Flashcards
(225 cards)
definition lisfranc injury
spectrum of injury from sprain to complete disruption of tarso-metatarsal joints in midfoot, usually occuring at base of 2nd metatarsal
mechanism of injury associated with lisfranc injury
foot being caught in a hole; falling off horse with foot caught in stirrup; MVC, foot planted in hole, awkward step off curb; bunk bed fracture (leaps onto bunk bed, landing on toes with axial load on plantar flexed ankle
MOA of lisfranc injury
plantar flexion with ER of ankle
Physical Exam findings for lisfranc fracture dislocations
unable to weight bear, hemtama/ecchymosis on plantar aspect of foot
X-Ray orders for LisFranc fracture
3 views - AP, later, standard 45 degrees oblique of foot
XRay findings for Lisfranc injury
widening between bases of 1st and 2nd or 2nd and 3rd metatarsal bases; > 2mm = surgical intervention
Normal alignment of metatarsals and tarsal bones in midfoot
AP view: edge of base 2nd metatarsal lining up with medial edge of medial cuniform; oblique: medial edge of 3rd and 4th metatarsal should line up with medial edges of middle and lateral cuniforms
Pathognomonic for lisfranc injury on XRay
fleck sign: small bony fragment avulsed from second metatarsal base or medial cuniform
Indications for surgery for lisfranc
displaced fracture or subluxation > 2 mm
If highly suspicious for lisfranc despite normal Xrays…
- 30 degrees oblique XRay (eliminate overlap of metatarsals), 2. weight-baring stress views following nerve block, 3. CT of foot
ED MGMT of LisFranc injury
posterior back slab
carpal bones (5) list them
scaphoid, lunate, triquetrum, pisiform, hamate, capitate, trapezoid, trapezium
(3) Physical tests to r/o scaphoid injury
- palpate scaphoid on palmer aspect with wrist radially deviated; 2. thumb axial load tenderness at scaphoid location 3. snuffbox tenderness
what is the watson test?
identifies scapholunate ligament injury or scaphoid fracture; start with palmer aspect on scaphoid wrist deivated ulnar and flexed, then move wrist radially with slight extension; (+) if pain, apprehension or clunk/subluxation
MOI for perilunate injuries
FOOSH
definition of perilunate dissociation
capitate dislocated from lunate
definition of lunate dissociation
lunate dislocated from capitate (more proximal one)
definition of scapholunate dissociation
terry thomas/madonna sign: visible gaps between teeth; gap of > 3 mm between scaphoid and lunate
FOOSH + acute carpal tunnel syndrome =
perilunate dissociation until proven otherwise
Xray finding for lunate dissociation
spilled tea cup - lunate is out of the seat of the capitate
ED MGMT of perilunate dislocation
90 degrees flexed at elbow with finger traps placed 10 - 15 lbs of longitudinal traction for 10 mins, if dorsally displaced, extend wrist and apply traction, then flex with volar/palmer pressure applied to lunate until clunk heard; volar/palmer slab!
DRUJ
distal radial ulnar joint injury
MOI of DRUJ
FOOSH injury +/- distal radial fracture
Physical findings for DRUJ
more prominent ulnar styloid, crepitus or blocking with pronation or supination, piano key sign, ulnar fovea sign