Forearm and Hand

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Humeral Head: medial epicondyle of humerus

  • Ulnar head: coronoid process of ulna

• Insertion:

  • Lateral surface of radius (distal to supinator)

• Innervation:

  • Median Nerve

• Main action:

  • Elbow flexion

  • Pronation of forearm

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Medical epicondyle of humerus

• Insertion:

  • Base of 2nd metacarpal

• Innervation:

  • Median nerve

• Main action:

  • Wrist flexion

  • Wrist abduction (radial deviation)

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Medial epicondyle of humerus

• Insertion:

  • Flexor retinaculum and palmar aponeurosis

• Innervation:

  • Median nerve

• Main action:

  • Wrist flexion

  • Tenses palmar aponeurosis

can be absent in some people

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Humeral head: medial epicondyle of humerus

  • Ulnar head: olecranon process and posterior border ulnar

• Insertion:

  • Pisiform, hook of hamate, base of 5th metacarpal

• Innervation:

  • Ulnar nerve

• Main action:

  • Wrist flexion

  • Wrist adduction (ulna deviation)

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Humero-ulnar head: medial epicondyle of humerus and conoid process of ulna

  • Radial head: Anterior radius (proximal half)

• Insertion:

  • Shafts of middle phalanges of digits 2-5

• Innervation:

  • Median nerve

• Main action:

  • Metacrapophalangeal joint flexion

  • Proximal interphalanges joint flexion

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Proximal ¾ of anterior surface off ulna

  • Interosseous membrane

• Insertion:

  • Base of distal phalanges of digits 2-5

• Innervation:

  • Medial half: ulna nerve

  • Lateral half: median nerve (via anterior interosseous nerve)

• Main action:

  • Distal interphalangeal joint flexion

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Anterior surface of radius

  • Interosseous membrane

• Insertion:

  • Base of distal phalanx of 1st digit

• Innervation:

  • Median nerve (via anterior interosseous nerve)

• Main action:

  • Flexion of 1st digit (thumb)

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Distal ¼ of anterior surface of ulnar

• Insertion:

  • Distal ¼ of anterior surface of radius

• Innervation:

  • Median nerve (via anterior interosseous nerve)

• Main action:

  • Pronation of forearm

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Lateral supracondylar ridge of humerus

• Insertion:

  • Lateral surface of distal radius

• Innervation:

  • Radial Nerve

• Main action:

  • Flexor of the forearm in mid prone position

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Lateral supracondylar ridge of humerus

• Insertion:

  • Base of the 2nd metacarpal

• Innervation:

  • Radial nerve

• Main action:

  • Wrist extension

  • Wrist abduction

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Lateral epicondyle of humerus

• Insertion:

  • Base of the 3rd metacarpal

• Innervation:

  • Radial nerve (via deep branch)

• Main action:

  • Wrist extension

  • Wrist abduction

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Lateral epicondyle of humerus

• Insertion:

  • Extensor expansion of digits 2-4

• Innervation:

  • Radial nerve (via deep branch)

• Main action:

  • Metacarpophalangeal joint extension (digits 2-5)

  • Proximal interphalangeal joint extension (digits 2-5)

  • Distal interphalangeal joint extension (digits 2-5)

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Lateral epicondyle of humerus

• Insertion:

  • Extensor expansion of 5th digit

• Innervation:

  • Radial nerve (via deep branch)

• Main action:

  • Metacarpophalangeal joint extension (5th digit)

  • Proximal interphalangeal joint extension (5th digit)

  • Distal interphalangeal joint extension (5th digit)

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Lateral epicondyle of humerus

  • Posterior border of ulna

• Insertion:

  • Base of 5th metacarpal

• Innervation:

  • Radial nerve (via deep branch)

• Main action:

  • Wrist extension

  • Wrist adduction

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Humeral head (superficial): lateral epicondyle of humerus, radial collateral and angular ligament

  • Ulnar head (deep): lateral aspects of proximal ulna

• Insertion:

  • Proximal third of radius, lateral, posterior and anterior surfaces

• Innervation:

  • Radial nerve (via deep branch)

• Main action:

  • Forearm supination

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Posterior surface of proximal hand of ulna and radius

  • Interosseous membrane

• Insertion:

  • Base of 1st metacarpal

• Innervation:

  • Radial nerve (via posterior interosseous nerve)

• Main action:

  • Abduction of thumb (which occurs at carpometacarpal joint)

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Posterior third of distal third radius

  • Interosseous membrane

• Insertion:

  • Base of proximal phalanx of 1st digit

• Innervation:

  • Radial nerve (via posterior interosseous nerve)

• Main action:

  • Metacarpophalangeal joint extension (1st digit)

  • Carpometacarpal joint extension (1st digit)

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Posterior surface of middle third ulna

  • Interosseous membrane

• Insertion:

  • Base of distal phalanx of 1st digit

• Innervation:

  • Radial nerve (via posterior interosseous nerve)

• Main action:

  • Interphalangeal joint extension (1st digit)

  • Metacarpophalangeal joint extension (1st digit)

  • Carpometacarpal joint extension (1st digit)

Origin:

Insertion:

Innervation:

Main action:

• Origin:

  • Posterior surface of distal third ulna

  • Interosseous membrane

• Insertion:

  • Extensor expansion 2nd digit

• Innervation:

  • Radial nerve (via posterior interosseous nerve)

• Main action:

  • Extend second digit (allows independent extension)

Origin:

Insertion:

Innervation:

Main action:

• Origin:

• Insertion:

• Innervation:

• Main action: