Wrist

Question 1

Name the structures bound by the extensor retinaculum of the wrist.

Answer 1

From lateral to medial, grouped by common synovial sheaths:

• Abductor pollicis longus + Extensor pollicis brevis
• ECRL + ECRB
• Extensor pollicis longus
• Extensor indicis + Extensor digitorum
• Extensor digiti minimi
• ECU

Question 2

What is the motor supply to the extensor muscles bound by the extensor retinaculum?

Answer 2

All from the radial nerve.  Specifically:
- Radial nerve directly
- Posterior interosseous nerve.
- Deep branch of radial nerve
All are C6 or C7 or C8

Question 3

Describe the sensory supply to the hand.

Answer 3

Radial: Dorsum of hand excluding distal digits
Ulnar: 5th digit and half of 4th digit
Median: 1st, 2nd, 3rd digit and half of 4th digit