SGL Case 4 - Anatomy

Hand/Wrist Osteology

100

This joint lies intermediate to the carpo-metacarpal joint and proximal interphalangeal joint

Metacarpo-phalangeal (MCP) Joint

200

This bone can be palpated in a divot on the dorsal surface of the hand in line with the third metacarpal

Lunate

Bonus: Lunate fractures usually result from what mechanism of injury?

300

These bony projections allow for abduction and adduction of the wrist joint

The radial and ulnar styloid processes

Bonus: Why can the wrist be abducted more than it can be adducted?

400

The wrist joint is made up of these 5 structures

4 bones: radius, scaphoid, lunate and triquetrum

cartilage: articular disc over the ulnar head

500

Name the 4 carpal bones of the proximal row (lateral to medial) and the 4 carpal bones of the distal row (lateral to medial)

Proximal row (L -> M): scaphoid, lunate, triquetrum, pisiform

Distal row (L -> M): trapezium, trapezoid, capitate, hamate

Anatomy Affected in RA

100

Tenosynovitis (tendon + synovial sheath inflammation) of the flexor tendons of the carpal tunnel can cause carpal tunnel syndrome symptoms in RA patients. Name them all

4 tendons of flexor digitorum superficialis

4 tendons of flexor digitorum profundis

tendon of flexor pollicis longus

200

Weakening of this wrist-stabilizing ligament contributes to the ulnar deviation characteristic of rheumatoid arthritis

Radial collateral ligament

300

De Quervain's tenosynovitis (often found in RA patients) affects these 3 tendons comprising the anatomical snuffbox

abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus

Bonus: Name/demonstrate the clinical test for De Quervain's tenosynovitis

400

While RA often affects multiple joints in the upper limb, this joint is usually unaffected

Distal interphalangeal joints

500

Tenosynovitis (tendon + synovial sheath inflammation) of the tendon of this forearm posterior compartment muscle can lead to erosion of the ulnar styloid process

Extensor carpi ulnaris