wrist/hand Flashcards
Percentage of upper limb function comprised by the hand
90%- 40-50% thumb
number of joints/ligaments in wrist?
more than 20 joints, 26 ligaments
joint of TFCC
ulnocarpal
proximal row of carpals
scaphoid lunate triquetrum pisiform
distal row of carpals (radial to ulnar)
trapezium, trapezoid, capitate, hamate
describe the two types of ligaments within the carpal bones
extrinsic volar ligaments: wrist stability
intrinsic ligaments: rotation restraints
ligaments of the finger
Ulnar/radial collateral
transverse retinacular: holds extensor mechanism at PIP joint
oblique retinacular ligament:
function of pulley system?
restrain flexor tendons sfrom bowstrining- completed by the annular (A1-A5 and thumb (A1, A@) and the cruciate (C1-C3)
function of the velar plate
attaches to base of proximal phalanx- strong capsulogliamentous support- resists hyper extension
extensor compartments
1: abductor pollicis longus, extensor pollicis brevis
2: extensor carpi radialis longus and brevis
3: extensor pollicis longus
4: extensor digitorum, extensor indicis
5: extensor digiti minimi
6: extensor carpi ulnaris
attachments of the transverse carpal ligament
radial: tubercle of trapezium and scaphoid
ulnar: hook of hamate and pisiform
**serves as attachment site for muscles, maintains transverse carpal arch and restrains bowstringing protects median nerve
(carpal tunnel site_
function of TFCC
improves joint congruency, cushions against compressive forces: transmits~20% of axial load from hand to forearm
intrinsic hand muscles (all of the rest are extrinsic )
abductor digiti minimi, fexor digiti minimi, interossei, lumbricals, adductor pollicis brevis, flexor pollicis brevis, opponens pollicis, adductor pollicis
Flexor tendon zones (fingers)
1: DIP joint distal
2: DIP joint to Distal Palmar Crease
3: distal palmar crease proximal to transverse carpal ligament
4: carpal tunnel
5: carpal tunnel to musculotendionous junction of flexor tendons
Flexor tendon zones (thumb)
1: IP joint distal
2: IP joint proximal to MP joint
3: MP joint proximal to transverse carpal ligament
Extensor tendon zones
1: DIP joints
2: middle phalanx
3: PIP joints
4: proximal phalanx
5: MP joints
6: metacarpals
7: carpals
extensor tendon zones (thumb)
IP joint middle phalanx MP joint 1st metacarpal carpals
limitations of pronation/supination
pronation: limited by impaction between radius and ulna
supination: limited by interossious membrane
flexion at the wrist
60% midcarpal joint
extension at wrist
66.5% radiocarpal joint
radial deviation
occurs at mid carpal joint
ulnar deviation
occurs primarily at radiocarpal joint
wrist ROM
pronation 0-75 supination 0-85 flexion 80 extension 70 radial deviaion 15 ulnar deviation 45
distal radio ulnar joint
ulnar convex
radial concave
radius on ulna- rolls and glides in SAME direction
radiocarpal
biconcave- convex carpals roll and glide in opposite direction for flexion/extension/radial/ulnar deviation
during radial deviation and ulnar deviation what happens at the proximal row?
radial deviation: flexes
ulnar deviation: extends
midcarpal joints
all distal convex moving on concave proximal EXCEPT concave trapezium/trapezoid moving on convex scaphoid
thumb ROM
radial abd: 55-60 palmar abd: 55-60 opposition: 0 MP flexion50-55 Ip flexion: 85-90
finger ROM
MP: 85-90 MP extension 30--45 MP abduction :20-30 PIP flexion: 100-115 DIP flexion: 80-90 DIP extension: 20 composite flexion: pulp to distal palmar crease 0 cm- funcitonal 1-2 cm
MCP and interphalangeal joints
concave on convex
