The Wrist and Hand Joints

Anatomy and Kinesiology

420:024

The Wrist and Hand Joints

Many sports require precise functioning of wrist & hand

Archery, bowling, golf, baseball, tennis, etc. require combined use of wrist & hand joints

Very complex 29 bones 25 joints 33 muscles

Objectives

Bones, bony landmarks and joints Muscles Movements

Bones

29 bones, including radius & ulna Carpals (8)

Two rows of 4 bones Metacarpals (5)

Numbered 1-5 Phalanges (14)

Three for each finger Two for the thumb

Thumb has a sesamoid bone in its flexor tendon Other sesamoids may occur in joints of fingers

Bones

Carpal bones form a three-sided arch Concave on palmar side creates the carpal tunnel Frequently a source of problems known as carpal tunnel

syndrome

Wrist and Hand Joints

Radiocarpal joint Biaxial ball and socket

Intercarpal joints Gliding/nonaxial

Carpometacarpal joints Fingers – Gliding/nonaxial Thumb – Biaxial saddle

Wrist and Hand Joints

Metacarpophalangeal joints Fingers – Biaxial ball and socket Thumb – Uniaxial hinge

Proximal interphalangeal joints Fingers – Uniaxial hinge

Distal interphalangeal joints Fingers – Uniaxial hinge

Interphalangeal joint Thumb – Uniaxial hinge

Objectives

Bones, bony landmarks and joint Muscles Movements

Wrist and Hand Muscles

Extrinsic muscles (15) All multiarticular

Elbow/wrist/hand (1) Elbow/wrist (6) Wrist/hand (8)

Intrinsic muscles (18)

Extrinsic Wrist and Hand Muscles (15) Elbow, Wrist and Hand (3)

Elbow flexion, wrist flexion, finger flexion (1) Elbow extension, wrist extension, finger extension (2)

Fingers 2, 3, 4, 5 Pinky

Elbow and Wrist (6) Elbow flexion, wrist flexion (3)

1 wrist abductor 1 wrist adductor 1 flexor only

Elbow flexion, wrist extension (2) 1 wrist abductor 1 wrist adductor

Elbow extension, wrist extension (1) Wrist adductor

Wrist and Hand (6) Wrist flexion, finger flexion (1) Wrist flexion, thumb flexion (1)

Wrist abductor Wrist extension, index finger extension (1) Wrist extension, thumb extension (2)

Wrist abductors Wrist flexion, thumb abduction (1)

Wrist abductor

Attachments Elbow, Wrist and Hand (3)

Elbow flexion, wrist flexion, finger flexion (1) Elbow extension, wrist extension, finger extension (2)

Fingers 2, 3, 4, 5 Pinky

Attachments Elbow, Wrist and Hand (3)

Elbow flexion, wrist flexion, finger flexion (1) Elbow extension, wrist extension, finger extension (2)

Fingers 2, 3, 4, 5 Pinky

Attachments

Elbow and Wrist (6) Elbow flexion, wrist flexion (3)

1 wrist abductor 1 wrist adductor 1 flexor only

Elbow flexion, wrist extension (2) 1 wrist abductor 1 wrist adductor

Elbow extension, wrist extension (1) Wrist adductor

Attachments

Elbow and Wrist (6) Elbow flexion, wrist flexion (3)

1 wrist abductor 1 wrist adductor 1 flexor only

Elbow flexion, wrist extension (2) 1 wrist abductor 1 wrist adductor

Elbow extension, wrist extension (1) Wrist adductor

Attachments

Elbow and Wrist (6) Elbow flexion, wrist flexion (3)

1 wrist abductor 1 wrist adductor 1 flexor only

Elbow flexion, wrist extension (2) 1 wrist abductor 1 wrist adductor

Elbow extension, wrist extension (1) Wrist adductor

Attachment Rules

Elbow/Wrist/Hand and Elbow/Wrist Muscles Wrist Flexors

Proximal: Medial or Lateral epicondyle of humerus Distal: Depends

Wrist Extensors Proximal: Medial or Lateral epicondyle of humerus Distal: Depends

Attachments

Wrist and Hand (6) Wrist flexion, finger flexion (1) Wrist flexion, thumb flexion (1)

Wrist abductor Wrist flexion, thumb abduction (1)

Wrist abductor Wrist extension, index finger extension (1) Wrist extension, thumb extension (2)

Wrist abductors

Attachments

Wrist and Hand (6) Wrist flexion, finger flexion (1) Wrist flexion, thumb flexion (1)

Wrist abductor Wrist flexion, thumb abduction (1)

Wrist abductor Wrist extension, index finger extension (1) Wrist extension, thumb extension (2)

Wrist abductors

Attachment Rules

Wrist/Hand Muscles Wrist Flexors

Proximal: Anterior or Posterior forearm Distal: Depends

Wrist Extensors Proximal: Anterior or Posterior forearm Distal: Depends

Intrinsic Muscles (18)