Hand and Wrist

Question 1

Describe the radiocarpal joint?

Answer 1

• condyloid joint
• articulation of the radius with proximal row of carapl bones
• Motions that occur here: flexion, extension, ulnar deviation, radial deviation, circumduction

Question 2

Name the 8 carpal bone

Answer 2

• Scaphoid
• lunate
• triquetrium
• pisiform
• trapexium
• trapezoid
• Capitate
• Hamate

Question 3

Describe the midcarpal bones

Answer 3

• intercarpal joints, plane joints–sliding and gliding
• Between proximal and distal row of carpal bones
• between adjacent carpal bones

Question 4

Describe the carpometacarpal joint?

Answer 4

• 1st CMC– the thumb is a saddle joint, very mobile, and allows for many motions: flexion, extension, abduction, adduction, opposition, and circumduction
• 2nd and 3rd CMC–index and middle fingers, fixed, irregular joints–no movement
• 4th CMC: ring finger, irregular joint, slightly mobile, 10 degrees of flexion, and also extension. (use when closing your fist)
• 5th CMC–pinky finger, irregular, more mobile, 20 degrees, flexion, extension, abduction, adduction, and opposition

Question 5

Describe the 5 metacarpalphalangeal joints

Answer 5

• 1st mcp: restricted condyloid, thumb, functions as a hinge joint (flex, extension)
• 2nd-5th MCP: true condyloid, knuckles of the fingers, flexion, extension, abduction. adduction, circumduction

Question 6

Describe the interphalangeal joints

Answer 6

• Only IP joint in the thumb
• hinge joint, actions: flexion and extension

Question 7

What does the wrist complex do?

Answer 7

• controls the length– tension relationship in the many joints of the hand
• The wrist is key to proper hand function–finger muscles are bale to function at their best when the wrist is in optimum position

Question 8

What are the wrist (radiocarpal) joint structures?

Answer 8

• capsule- strong but somewhat loose joint capsule to permit biaxial motions of the wrist
• Capsule is reinforced ligaments
• Midcarpal joint of the hand acts as functional unit to help facilitate radial and ulnar deviation at the wrist
• Ligaments: palmar, dorsal, ulnar, and radial collateral

Question 9

Describe palmar (volar) radiocarpal & dorsal radiocarpal

Answer 9

• Palmar radiocarapal ligament: on anterior surface of wrist, becomes taut and stabilizes with wrist extension
• Dorsal radiocarpal ligament: on posterior surface of wrist, becomes taught on wrist flexion

Question 10

Describe ulnar collateral and radial collateral ligament?

Answer 10

• Ulnar collateral: on medial side of the wrist, becomes taut and stabilizes with wrist and radial deviation
• Radial collateral: on lateral side of wrist, beocmes taut and stabilizes with wrist ulanr deviation.

Question 11

What are the biomechanics of the wrist?

Answer 11

• when the wrist is in slight ulnar deviation, it produces hand position good for power actvities (hammering, sawing, ect)
• when the wrist is in slight extension and radial deviation it is good for prescision activities (writing, seqing, buttoning a shirt)

Question 12

What are the anterior and posterior wrist muscles?

Answer 12

Anterior:
* Flexor carpi radialis
* Flexor carpi ulnaris
* Palmaris longus

Posterior:
* Extensor carpi radialis brevis
* Extensor carpi radialis longus
* Extensor carpi ulnaris