Hand and Wrist Flashcards
Site of compression of the median nerve
Supracondylar process/ligament of Struthers
Lacertus fibrosus
Between humeral and ulnar heads of Pronator teres
Fibrous origin of FDS (sublimus bridge)
Ganzer’s accessory FPL (AIN compression)
Sites of compression of ulnar nerve
Medial intermuscular septum
Arcade of Struthers
Hypertrophied medial head of triceps
Cubital tunnel (Osborne’s ligament)
Anconeus epitrochlearis
Between humeral and ulnar heads of FCU
Deep flexor-pronator aponeurosis
Sites of compression of radial nerve
FREAS
Fibrous bands proximal to radiocapitellar joint
Radial recurrent vessels (Leash of Henry)
ECRB leading edge
Arcade of Frohse
Supinator (as it exits)
Order of innervation of Radial nerve and PIN
Radial
Triceps, lateral 1/3 of brachialis, anconeus, brachioradialis, ECRL
PIN
ECRB, Supinator, ECU, EDC, EDM, APL, EPL, EPB, EI
Order of innervation of ulnar nerve
FCU, FDP 3&4, ADM, ODM, FDM, Lumbricals 3&4, Deep head FPB, Adductor pollicus, Interossei
Order of innervation of median nerve / AIN
AIN
FDP 1&2
FPL
PQ
Median
PT, FCR, PL, (AIN) FDS, APB, FPB (superficial), OP, Lumbricals 1&2
Principles of tendon transfers (8)
SADISSMS
Strength (Will lose 1 power grade)
Amplitude (Equal excursion)
Direction (straight line of pull)
Integrity (one tendon, one function)
Synergism
Sensate joint
Mobile joint
Soft tissue coverage
Tendon transfers for high radial nerve palsy and PIN palsy
Elbow extension
Deltoid/lat dorsi/biceps to triceps
Wrist extension
PT to ECRB
**When only PIN out, do side to side ECRL to ECRB
Digit extension
FCR to EDC
Thumb extension
PL (or FDS long/ring) to EPL
Transfers for a low median nerve palsy
Opponensplasties
Bunnell: FDS (ring) to base of prox. phalanx or APB (using FCU as a pulley)
Burkhalter: EIP to APB
Camitz: PL to APB
Huber: ADM to APB
Tendon transfers for high median nerve palsy.
Thumb opposition
Opponensplasty (can’t use FDS! Use EIP)
Index/long flexion
FDP ring/small to FDP index/long
Thumb IP flexion
Brachioradialis to FPL
Tendon transfers for ulnar nerve palsy
Thumb pinch
FDS (ring) or ECRB* to adductor pollicis
Index pinch
EIP or APL slip to 1st dorsal interosseous
Ring/Small clawing
FDS to radial lumbrical insertion (Stiles Bunnell)
(another option for claw digit: Zancolli Lasso - FDS cut, woven back over A1 pulley to itself)
*ECRB may require graft for required length
Thumb tendon insertions:
APB/FPB/OP
APL/EPB/EPL
APB: prox phalanx
FPB: prox phalanx
OP: metacarpal
APL: metacarpal
EPB: base prox phalanx
EPL: base distal phalanx
Name the classification for basal joint thumb arthritis.
Bonus: Name of basal thumb AP xray
Eaton & Littler
- Slight joint narrowing
- Sclerotic CMC, osteophytes <2mm
- Osteophytes >2mm
- Pan-trapezial OA
Roberts view
Contributions to DRUJ stability
DRUL: primary stabilizer of dorsal displacement of radius
PRUL: primary stabilizer of palmar displacement of radius
Bony DRUJ: confers approx 20% of DRUJ stability
Distal IOM: contributes to dorsal stability of radius
ECU sheat and Ulnocarpal ligs: contribute minimally to DRUJ stability.
Outline classification and mgmt of Kienbock’s dz
Lichtman classification:
- Normal xray (cast 6 weeks)
- Lunate sclerosis
3A. Lunate collapse with NO scaphoid rotation
(Tx is forage/decompression, vasc BG to lunate, capitate shortening osteotomy, radial wedge if ulnar positive, radial shortening if ulnar negative)
3B. Lunate collapse WITH scaphoid rotation
(Tx is lunate excision with STT/SC fusion; or PRC)
- Pancarpal OA
(Tx is wrist fusion)
Percunateously fixed scaphoid fractures vs cast treatment?
Faster rate of healing
Earlier return to work
In a DISI deformity, what does the scaphoid do?
Flexes and PRONATES
Mayfield classification
- Scapholunate
- Scaphocapitate
- Lunotriquetral
- Volar lunate dislocation
Stages of SLAC wrist and stages of SNAC wrist
SLAC
- Arthritis b/w scaphoid and radial styloid
- Arthritis of whole scaphoid fossa
- Capitolunate arthritis
SNAC
- Arthritis b/w scaphoid and radial styloid
- Scaphocapitate arthritis
- Capitolunate arthritis
Periscaphoid arthrosis (proximal lunate and capitate may be maintained)
Both end off with pan carpal arthritis.
List xray findings of scapholunate dissociation.
AP
Widened SL interval, scaphoid(signet)ring sign, triangular shaped lunate (extended lunate), widened triquetrum (from also being extended), decreased carpal height ratio (<54%)
Lateral
SL angle >60degrees, Lunate/triquetrum dorsiflexed (DISI), Radiolunate angle >15deg, Carpal V sign of Taleisnik (normally volar margins of scaphoid and DR assume a C shape)
How do you measure the carpal height ratio?
Carpal height/3rd MC length
Carpal height: distance between DR articular surface and distal articular surface of capitate
Average is 54%
Explain Bunnell test for intrinsic muscle tightness
More PIP flexion with MCPs flexed than with MCPs extended.
MCP extension places intrinsics on stretch.
MCP flexion relaxes intrinsics.