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

Objectives Bones, bony landmarks and joint Muscles Movements

Wrist and Hand Muscles Extrinsic muscles (15) Intrinsic muscles (18) 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) 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)

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) 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) 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) 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

Attachments Wrist and Hand (6) Wrist flexion, finger flexion (1) Wrist flexion, thumb flexion (1) Wrist abductor Wrist flexion, thumb abduction (1) 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 extension, index finger extension (1) Wrist extension, thumb extension (2) Wrist abductors

Attachment Rules Wrist/Hand Muscles Wrist Flexors Wrist Extensors Proximal: Anterior or Posterior forearm Distal: Depends Wrist Extensors

Intrinsic Muscles (18)