Hand / Wrist Muscles, Tendons, & Nerves

Question 1

Treatment for mallet finger

Answer 1

Non-operative splinting for 6-8 weeks, unless the injury is a large bony mallet or subluxation at the DIP joint, which is treated surgically.

Question 2

What causes a Boutonniere fracture?

Answer 2

Trauma –> rupture of central slip insertion on proximal phalanx → PIP flexion + DIP extension

Question 3

What side of wrist does RA more often affect?
Which joints?
Which tendon often ruptures?

Answer 3

Ulnar
MCP and DRUJ joints
RA may cause rupture of wrist extensor tendon (extensor pollicis longs).

Question 4

What joints in the hand does OA usually affect?

Answer 4

DIP and thumb CMC joints

Question 5

Which muscles in the forearm does the median nerve NOT innervate?

Answer 5

Innervates all forearm muscles except FCU and ulnar half of FDP.

Question 6

Which muscles does deep branch of ulnar nerve innervate? (5)

Answer 6

Hypothenar muscles, 3rd / 4th lumbricals, adductor polllicis, all interossei, and deep head of FPB (flexor pollicis brevis).