Hand and Wrist

Question 1

Name the 8 carpal bones and their orientation

Answer 1

Carpal Bones

• 2 rows of 4 bones each
• Proximal (lateral to medial)
  
  • Scaphoid, Lunate, Triquetrum, Pisiform
• Distal (lateral to medial)
  
  • Trapezium, Trapezoid, Capitate, Hamate
    
    • Trapezoid is on the insoid
    • Trapezium is for the thumb

Some Lovers Try Positions That They Can’t Handle

(proximal row lateral to medial; then distal row lateral to medial)

Metacarpals - 5 bones

Phalanges - 14 Bones (4*3 + 2 = 14)

Question 2

Name the 4 joints of the hand

Answer 2

1. Radiocarpal (RC) - wrist joint btw radius and proximal row of carpals
   
   1. Condyloid synovial joint - F, E, Add, Abd all possible
2. Intercarpal (IC)
   
   1. Gliding Synovial
3. Carpometacarpal (CMC)
   
   1. relatively immobile
4. Metacarpophalangeal (MCP)
   
   1. Condyloid synovial - F, E, Add, Abd
5. Interphalangeal (IP)
   
   1. Hinge Synovial joint - F and E only

Question 3

What muscles control wrist flexion, extension, abduction, and adduction?

Answer 3

• Adduction
  
  • FCU + ECU
• Abduction
  
  • FCR + ECRL/ECRB
• Flexion
  
  • FCU + FCR
• Extension
  
  • ECU + ECRL/ECRB

Question 4

Contents of the Canal of Guyon?

Answer 4

1. Ulnar Nerve and Artery
2. NO tendons

Question 5

Anatomic Snuff box contents?

Answer 5

• APL (lateral border)
• EPB
• EPL (medial border)
• Radial a. and superficial (cutaneous) branch of the radial n.

Question 6

How do you test for radial nerve function?

Answer 6

You test by resisting extending at the MCP joints

(you can’t test at IP joints because lumbricals and interossei provide extension and are innervated by deep branch of ulnar)