UE Muscle Packet

Brachialis

PA: Distal ½ of anterior surface of humerus

DA: Coronoid process and ulnar tuberosity

A: Elbow flexion

N: Musculocutaneous (C5, C6) and Radial (C5, C7)

Aconeus

PA: Lateral epicondyle of humerus

DA: Lateral surface of olecranon and superior part of posterior surface of ulna

A: Elbow extension, stabilizes elbow joint

N: Radial (C7, C8, T1)

Palmaris Longus

PA: Medial epicondyle of humerus (common flexor origin)

DA: Distal half of flexor retinaculum and apex of palmar aponeurosis

A: Wrist flexion, tenses palmar aponeurosis

N: Median (C7, C8)

Flexor Digitorum Superficialis

PA:

• Humeroulnar head: Medial epicondyle (common flexor origin) coronoid process

• Radial head: Superior ½ of anterior border of radius

DA: Shafts of middle phalanges 2nd - 5th digits

A: DIP flexion of 2nd - 5th digits

N:

• Medial part: Ulnar (T1)

• Lateral part: Median (anterior interosseous) (C8)

Flexor Digitorum Profundus

PA: Proximal ¾ of medial and anterior surface of ulna and interosseous membrane

DA:

• Medial part: Base of distal phalanges of 4th and 5th digits

• Lateral part: Base of distal phalanges of 2nd and 3rd digits

A: DIP flexion of 2nd - 5th digits

N:

• Medial part: Ulnar (T1)

• Lateral part: Median (anterior interosseous) (C8)

Flexor Pollicis Longus

PA: Anterior surface of radius and adjacent interosseous membrane

DA: Base of distal phalanx of 1st digit

A: IP and MP flexion of 1st digit

N: Median (anterior interosseous) (C8)

Extensor Digitorum

PA: Lateral epicondyle of humerus (common extensor origin)

DA: Extensor expansions of 2nd - 5th digits

A: MP, DIP, and PIP extension of 2nd - 5th digits

N: Radial (posterior interosseous) (C7)

Extensor Digiti Minimi

PA: Lateral epicondyle of humerus (common extensor origin)

DA: Extensor expansion of 5th digit

A: MP, DIP, and PIP extension of 5th digit

N: Radial (posterior interosseous) (C7)

Extensor Indicis

PA: Posterior surface of distal third of ulna and interosseous membrane

DA: Extensor expansion of 2nd digit

A: MP, DIP, PIP extension of 2nd digit enabling its independent extension. Wrist extension.

N: Radial (posterior interosseous) (C7)

Opponens Pollicis

PA: Flexor retinaculum and tubercles of scaphoid and trapezium

DA: Lateral side of 1st metacarpal

A: Opposition of 1st digit

N: Median (recurrent branch) (C8)

Flexor Pollicis Brevis

PA: Flexor retinaculum and tubercles of scaphoid and trapezium

DA: Lateral side of base of proximal phalanx of 1st digit

A: MP flexion of 1st digit

N:

• Superficial head: Median (recurrent branch) (C8)

• Deep head: Ulnar (deep branch) (T1)

Adductor Pollicis

PA:

• Oblique head: base of 2nd and 3rd metacarpals, capitate, and adjacent carpals

• Transverse head: anterior surface of shaft of 3rd metacarpal

DA: Medial side of base of the proximal phalanx of 1st digit

A: CMC adduction of 1st digit

N: Ulnar (deep branch) (T1)

Abductor Digiti Minimi

PA: Pisiform

DA: Medial side of base of proximal phalanx of 5th digit

A: MP abduction and flexion of 5th digit

N: Ulnar (deep branch) (T1)

Flexor Digiti Menimi Brevis

PA: Hook of hamate and flexor retinaculum

DA: Medial side of base of proximal phalanx of 5th digit

A: MP flexion of 5th digit

N: Ulnar (deep branch) (T1)

Opponens Digiti Minimi

PA: Hook of hamate and flexor retinaculum

DA: Medial border of 5th metacarpal

A: Opposition of 5th digit

N: Ulnar (deep branch) (T1)

Palmar Brevis

MA: Skin on the medial border of the hand

LA: Medial border of the palmar aponeurosis

A: Wrinkles the skin of the hypothenar eminence and deepens the hollow of the palm

N: Ulnar (superficial branch) (C8, T1)

Lumbricals

PA: Tendons of flexor digitorum profundus

DA: Lateral sides of extensor expansion of 2nd - 5th digits

A: MP flexion, DIP, PIP extension of 2nd - 5th digits

N:

• Radial 2 digits: Median (T1)

• Ulnar 2 digits: Ulnar (deep branch) (T1)

Palmar Interossei (1-3)

PA: Palmar surface of 2nd, 4th, and 5th metacarpals. (unipennate)

DA: Base of proximal phalanges; extensor expansion of 2nd, 4th, 5th, digits:

• 1st into ulnar side of 2nd digit

• 2nd and 3rd into radial side of 4th and 5th digits

A: Adduction of digits 2, 4, and 5, toward axial line, assists lumbricals in MP flexion. Extension of PIP, DIP, and extensor expansions of 2nd, 4th, 5th digits.

N: Ulnar (deep branch) (T1)