Ch 4 - MSK: Wrist

Question 1

Describe the ROM of the wrist.

Answer 1

• Flexion: 80°
• Extension: 70°
• Ulnar deviation 30°
• Radial deviation: 20°

Question 2

What is the proximal row of carpal bones in the radial to ulnar direction?

Answer 2

“Some Lovers Try Positions” 
 – Scaphoid
 – Lunate
 – Triquetrum
 – Pisiform

Question 3

What is the distal row of carpal bones in the radial to ulnar direction?

Answer 3

“That They Can’t Handle”
 – Trapezium
 – Trapezoid
 – Capitate
 – Hamate

Question 4

Describe muscles and innervation involved with wrist flexion.

Answer 4

• FCR (median n, median + lateral cords: C6, C7)
• FCU (ulnar n, medial cord: C8, T1)
• Palmaris longus (median n, medial + lateral cords: C7, C8)
• FDS (median n, medial + lateral cords: C7, C8, T1)
• FDP (median n, medial + lateral cords C7, C8, T1 to 2nd and 3rd digit; ulnar n, medial cord: C7, C8, T1 to 4th and 5th digit)
• FPL (median n, medial + lateral cords: C8, T1)

Question 5

Describe muscles and innervation involved with wrist Extension.

Answer 5

• ECRL (radial n, posterior cord: C6, C7)
• ECRB (radial n, posterior cord: C6, C7)
• ECU (radial n, posterior cord: C7, C8)
• EDC (radial n, posterior cord: C7, C8) • EDM (ulnar n, medial cord: C8, T1)
• Extensor indicis (radial n, posterior cord: C6, C7, C8)
• EPL (radial n, posterior cord: C6, C7, C8)

Question 6

Describe muscles and innervation involved with ulnar deviation of the wrist (adduction).

Answer 6

• FCU (ulnar n, medial cord: C8, T1)

* ECU (radial n, posterior cord: C7, C8)

Question 7

Describe muscles and innervation involved with radial deviation of the wrist (abduction).

Answer 7

• FCR (median n, medial + lateral cords: C6, C7)

* ECRL (radial n, posterior cord: C6, C7

Question 8

What is in the first compartment on the wrist?

Answer 8

– Abductor pollicis longus

– Extensor pollicis brevis

Question 9

What is in the second compartment on the wrist?

Answer 9

– Extensor carpi radialis longus

– Extensor carpi radialis brevis

Question 10

What is in the third compartment on the wrist?

Answer 10

– Extensor pollicis longus

Question 11

What is in the fourth compartment on the wrist?

Answer 11

– Extensor digitorum communis

– Extensor indices proprius

Question 12

What is in the fifth compartment on the wrist?

Answer 12

– Extensor digiti minimi

Question 13

What is in the sixth compartment on the wrist?

Answer 13

– Extensor carpi ulnaris

Question 14

What wrist joint is commonly involved in OA?

Answer 14

First carpometacarpal (CMC) joint of the thumb

Question 15

Describe testing for CMC OA.

Answer 15

Axial compression of the metacarpal on the trapezium gives a painful grinding sensation

Question 16

Describe wrist involvement of RA.

Answer 16

– Ulnar deviation of the MCPs
– Radial deviation of the wrist
– Dorsal subluxation of the ulna
– Erosion of the ulnar styloid at the end stag

Question 17

Which tendons are involved in de Quervain’s tenosynovitis?

Answer 17

APL

EPB

Question 18

What is a ganglion cyst?

Answer 18

Synovial fluid-filled cystic structure that arises from the synovial sheath of the joint space

Question 19

Where do ganglion cysts typically occur in the wrist?

Answer 19

60% dorsal aspect

Question 20

What are treatments for ganglion cyst?

Answer 20

• Immobilization
• Aspiration of the cyst (90% recurrence)
• Surgical removal (10% recurrence)

Question 21

What is Kienböck’s disease?

Answer 21

Osteonecrosis of the lunate

Question 22

What is the cause of Kienböck’s disease?

Answer 22

Vascular impairment Repeated stress or fx

Question 23

What are risk factors for Kienböck’s disease?

Answer 23

• Poor vascular supply

* Short ulnar variance

Question 24

What is the clinical presentation of Kienböck’s disease?

Answer 24

• Ulnar-sided pain, stiffness, and swelling over the dorsal aspect of the wrist directly over the lunate
• Reduced grip strength