Hand Pathologies Flashcards
Double Crush refers to…
Proximal N compression causes distal N to be more sensitive to impingement
Most commonly compressed N
Median (carpal tunnel)
Most commonly injured N
Radial
Carpal Tunnel Syndrome: risk factors
Fx
pregnancy
diabetic neuropathy
arthritis
tumor
synovitis
Carpal Tunnel Syndrome: possible cause
Repeated forceful grip + wrist flex (typing, construction)
But exact MOI not clearly defined
Carpal Tunnel Syndrome: conservative treatment
Neutral splint
Steroid injection
Median N glides
FDS/FDP Tendon glides (contraindicated if post-op)
Carpal Tunnel Syndrome: diagnosed with…
electrodiagnostic testing
Carpal Tunnel Syndrome: presentation
Paresthesia in volar thumb, index, mid.
Loss of dexterity (later stages).
High Radial N Injury: MOI
Humerus fx
High Radial N Injury: presentation
Radial N Palsy aka “Wrist Drop Deformity”
Still able to supinate (biceps takes over).
High Radial N Injury: treatment
Splint to prevent flexion contracture.
Resolves within 4mo.
If no improvement at 6mo = surgery.
Low Radial N Injury: what N is compressed?
PIN
Low Radial N Injury: MOI
Temporary compression of PIN (motor N).
Radial head fx, tumor, repetitive sup/pro.
Low Radial N Injury: presentation
“Saturday Night Palsy”
Sensation intact if only PIN affected
Ulnar N Injury: causes
Prolonged severe cubital tunnel.
Ulnar N laceration.
High Ulnar N Injury: presentation
Claw Hand
Sensory loss in ulnar N distrib (pinky & ulnar half of ring).
Weak FCU & FDP of pinky & ring.
Low Ulnar N Injury: presentation
Claw Hand
Sensory loss in ulnar N distrib.
Weak intrinsics.
Thenar & hypothenar musc wasting (Guyon’s Canal Syndrome).
Ulnar N Injury: treatment
Anti-claw splint.
Elbow ext splint.
Check ROM every other day.
Thumb UCL Injury: MOI
Hyperext + RD
Skier’s Thumb (rupture) or Gamekeeper’s Thumb (laxity)
Thumb UCL Injury: presentation
laxity of >15° with valgus stress, lack of firm end feel.
Thumb UCL Injury: treatment for complete tear
surgery
Thumb UCL Injury: treatment for partial tear
cast/splint 4-6wks
PIP Dislocation MOI
Most common = dorsal.
Hyperext + compressive stress.
Volar Plate often ruptures.
Boutinnere Deformity
Central tdn of extensor mechanism injured.
Hyperextended DIP & flexed PIP.
Swan Neck Deformity
Volar plate disrupted, lateral bands pull dorsally.
Flexed DIP & hyperextended PIP.
Mallet Finger
Direct axial load to digit, avulsion of terminal tdn on distal phalanx.
Flexed DIP.
Tendon Adhesions
Concern with both post-op and non-op tendon injuries.
Scar tissue in sheath from increased protein material.
Most commonly Zone 2 (because lowest vascularity).
Dequervain’s Tenosynovitis: MOI
Microtrauma of APL + EPB (1st extensor dorsal compartment).
Repeated thumb ABD w/ ulnar deviation (post-partum laxity & repeated picking up kid)
Dequervain’s Tenosynovitis: presentation
Pain in snuff box
How to distinguish OA vs RA
OA = unilateral
RA = bilateral
OA presentation
Grip compensation with CMC flex + MP hyperext + IP flex
RA - which side is more commonly affected & how does it present?
Radial side
Results in UD
Dupuytren’s Disease
Fibrosis & eventual contractures of palmar/digital fascia.
Trigger Finger
Thickening of FDS tendon sheath.
Sometimes nodules - tdn catches as it glides.
Ganglion Cyst
Synovial cyst
Often dorsal
