anatomy Flashcards
where does the central slip insert and what does it do?
base of middle phalanx, extends PIP
where do the lateral bands insert and what do they do?
distal phalanx, extends DIP
what deformity does contracture of the oblique band of the retinacular ligament cause?
boutonierre deformity (volar displacement of lateral bands)
what deformity does loosening of the transverse band of the retinacular ligament cause?
swan neck deformity (dorsal translation of lateral bands)
what do the sagittal bands do?
keeps extensor mechanism tracking in midline during flexion of MP joint
course of radial artery to hand
runs between brachioradialis and FCR, enters dorsum of carpus by passing between FCR and APL/EPB tendons in the snuffbox, gives off superficial palmar branch (goes to superficial arch) and deep palmar arch
course of ulnar artery to hand
runs under FCU, runs lateral to ulnar nerve at the wrist, enters the hand through Guyon’s canal. lies on transverse carpal ligament
main blood supply to superficial palmar arch
ulnar artery
main blood supply to deep palmar arch
deep branch of radial artery
what is the most radial structure in the carpal tunnel?
FPL
where is flexor tendon zone 1?
distal to FDS insertion
where is flexor tendon zone 2?
FDS insertion to distal palmar crease/proximal A1 pulley
where is flexor tendon zone 3?
palm (A1 pulley to distal aspect of carpal ligament)
where is flexor tendon zone 4?
carpal tunnel
where is flexor tendon zone 5?
carpal tunnel to forearm
extensor tendon zone 1
terminal extensor tendon distal to or at DIP joint
extensor tendon zone 2
middle phalanx
extensor tendon zone 3
PIP joint (central slip)
extensor tendon zone 4
proximal phalanx
extensor tendon zone 5
MCP joint
extensor tendon zone 6
metacarpal
extensor tendon zone 7
wrist joint
extensor tendon zone 8
distal foream, extensor muscle belly
major and minor blood supply to scaphoid
major = dorsal carpal branch of radial artery, minor = superficial palmar arch
what makes up guyon’s canal?
roof = superficial palmar ligament
floor = deep flexor retinaculum, hypothenar muscles
ulnar border = pisiform and pisohamate ligament
radial border = hook of hamate
what makes up the TFCC?
dorsal and volar radioulnar ligament, central articular disc, meniscus homolog, ulnar collateral ligament, ECU subsheath, origin of ulnolunate and ulnotriquetral ligaments
what are the borders of the carpal tunnel?
radial = scaphoid tubercle, trapezium ulnar = hook of hamate, pisiform roof = transverse carpal ligament floor = proximal carpal row
what is the most radial structure in the carpal tunnel?
FPL
what muscles are innervated by the AIN?
FDP (index and middle finger), FPL, pronator quadratus
what are the connections of the ligament of struthers?
supracondylar process to medial epicondyle
what are the boundaries of the cubital tunnel?
roof: FCU fascia and Osborne’s ligament
floor: posterior and transverse bands of MCL and joint capsule
walls: medial epicondyle and olecranon
what are the connections of osborne’s ligament?
medial epicondyle to olecranon
what are the borders of Guyon’s canal?
floor - transverse carpal ligament, hypothenar muscles
roof - volar carpal ligament
ulnar border - pisiform and pisohamate ligament, abductor digiti minimi muscle belly
radial border - hook of hamate
what does the deep branch of the ulnar nerve innervate?
all interosseus muscles, third and fourth lumbricals, hypothenar muscles, adductor pollicis, medial head of FPB
what is the leash of henry?
recurrent radial vessels that fan across the PIN at the level of the radial neck
what is the arcade of frohse?
proximal edge of superficial portion of supinator
what does the PIN innervate?
common extensors (ECRB, EDC, ECM, ECU), deep extensors (supinator, APL, EPB, EPL, EIP), dorsal wrist capsule
what structure is involved in de quervain’s?
dorsal compartment 1 (APL, EPB)
