Chap 7: Wrist and Hand ACTION, ORIGIN, INSERTION, SPINAL + PERIPHERAL NERVE INNERVATION

Flexor Carpi Radialis

Action: Flex the wrist (radiocarpal joint); Radially deviate the wrist (radiocarpal joint); May assist to flex the elbow (humeroulnar joint)

Origin: Common flexor tendon from medial epicondyle of humerus

Insertion: Bases of 2nd and 3rd metacarpals

Spinal + Peripheral Nerve Innervation: Median C6 to C8

Flexor Carpi Ulnaris

Action: Flex the wrist (radiocarpal joint); Ulnarly deviate the wrist (radiocarpal joint); Assist to flex the elbow (humeroulnar joint)

Origin: Humeral head: Common flexor tendon from medial epicondyle of humerus; Ulnar head Posterior surface of proximal two-thirds of ulna

Insertion: Pisiform, hook of the hamate, and base of 5th metacarpal

Spinal + Peripheral Nerve Innervation: Ulnar C7 and C8, T1

Palmaris Longus

Action: Tense the palmar fascia; Flex the wrist (radiocarpal joint); May assist to flex the elbow (humeroulnar joint)

Origin: Common flexor tendon from medial epicondyle of humerus

Insertion: Flexor retinaculum and palmar aponeurosis

Spinal + Peripheral Nerve Innervation: Median C6 to C8, T1

Flexor Digitorum Superficialis

Action: Flex the 2nd through 5th fingers (metacarpophalangeal joint and proximal interphalangeal joints); Flex the wrist (radiocarpal joint)

Origin: Common flexor tendon from medial epicondyle of humerus, ulnar collateral ligament, coronoid process of ulna, interosseous membrane, and proximal shaft of radius

Insertion: Sides of middle phalanges of 2nd through 5th fingers

Spinal + Peripheral Nerve Innervation: Median C7 and C8, T1

Flexor Digitorum Profundus

Action: Flex the 2nd through 5th fingers (metacarpophalangeal joint and distal interphalangeal joint), Assist to flex the wrist (radiocarpal joint)

Origin: Anterior and medial surfaces of proximal three quarters of ulna

Insertion: Bases of distal phalanges, volar surface of 2nd through 5th fingers

Spinal + Peripheral Nerve Inervation: 2nd and 3rd fingers: Median C7 and C8, T1; 4th and 5th fingers: Ulnar C7 and C8, T1

Flexor Pollicis Longus

Action: Flex the thumb (interphalangeal joint; Flex the thumb (metacarpophalangeal and carpometacarpal joints); Assist to flex the wrist (radiocarpal joint)

Origin: Anterior surface of radius and interosseous

membrane

Insertion: Base of distal phalanx of thumb

Spinal + Peripheral Nerve Innervation: Median C6 to C8, T1

Extensor Carpi Radialis Longus + Brevis

Action: Extend the wrist (radiocarpal joint); Radialy deviate the wrist (radiocarpal joint); Assist to flex the elbow (humeroulnar joint)

Origin: Longus: Distal one-third of the later supracondylar ridge of humerus; Brevis: Common extensor tendon from the lateral epicondyle of the humerus

Insertion: Longus: Base of 2nd metacarpal; Brevis: Base of 3rd metacarpal

Spinal + Peripheral Nerve Innervation: Longus: Radial C5 to C8; Brevis: Radial C6 to C8

Extensor Carpi Ulnaris

Action: Extend the wrist (radiocarpal joint); Ulnarly deviate the wrist (radiocarpal joint)

Origin: Common extensor tendon from lateral epicondyle of humerus

Insertion: Base of 5th metacarpal

Spinal + Peripheral Nerve Innervation: Radial C6 to C8

Extensor Digitorum

Action: Extend the 2nd through 5th fingers (metacarpophalangeal and interphalangeal joints); Assist to extend the wrist (radiocarpal joint)

Origin: Common extensor tendon from lateral epicondyle of humerus

Insertion: Bases of middle and distal phalanges of 2nd through 5th fingers

Spinal + Peripheral Nerve Innervation: Radial C6 to C8

Extensor Indicis

Action: Extend the 2nd finger (metacarpophalangeal joint); Adduct the second finger; May assist to extend the wrist (radiocarpal joint)

Origin: Posterior surface of distal shaft of ulna and interosseous membrane

Insertion: Tendon of the extensor digitorum at the level of the 2nd metacarpal

Spinal + Periperal Nerve Innervation: Radial C6 to C8

Abductor Pollicis Longus

Action: Radially abduct the thumb (carpometacarpal joint); Extend the thumb (carpometacarpal joint); Radially deviate the wrist (radiocarpal joint)

Origin: Posterior surface of radius and ulna, and interosseous membrane

Insertion: Base of 1st metacarpal

Spinal + Peripheral Nerve Innervation: Radial C6 to C8

Extensor Pollicis Longus and Brevis

Action: Extend the thumb (interphalangeal joint), EPL only; Extend the thumb (metacarpophalangeal and carpometacarpal joint); Radially deviate the wrist (radiocarpal joint)

Origin: Longus: Posterior surface of ulna and interosseous membrane; Brevis: Posterior surface of radius and interosseous membrane

Insertion: Longus: Base of distal phalanx of thumb; Brevis: Base of proximal phalanx of thumb

Spinal + Peripheral Nerve Innervation: Radial C6 to C8

Abductor Pollicis Brevis

Action: Abduct the thumb (carpometacarpal and metacarpophalangeal joints), Assist in opposition of thumb

Origin: Flexor retinaculum, trapezium, and scaphoid tubercles

Insertion: Base of proximal phalanx of thumb

Spinal + Peripheral Nerve Innervation: Median C6 to C8, T1

Flexor Pollicis Brevis

Action: Flex the thumb (carpometacarpal and metacarpophalangeal joints); Assist in opposition of thumb

Origin: Superficial head: Flexor retinaculum; Deep head: Trapezium, trapezoid, and capitate

Insertion: Base of proximal phalanx of thumb

Spinal + Peripheral Nerve Innervation: Superficial head: Median C6 to C8, T1; Deep head: Ulnar C8 and T1

Opponens Pollicis

Action: Opposition of the thumb at the carpometacarpal joint (bringing the pads of the thumb and 5th finger together)

Origin: Flexor retinaculum and tubercle of the trapezium

Insertion: Entire length of 1st metacarpal bone, radial surface

Spinal + Peripheral Nerve Innervation: Median C6 to C8, T1

Abductor Digiti Minimi

Action: Abduct the 5th finger (metacarpophalangeal joint); Assist in opposition of the 5th finger toward the thumb (metacarpophalangeal joint)

Origin: Pisiform and tendon of flexor carpi ulnaris

Insertion: Base of proximal phalanx of 5th finger, ulnar surface

Spinal + Peripheral Nerve Innervation: Ulnar C7 and C8, T1

Flexor Digiti Minimi

Action: Flex the 5th finger (metacarpophalangeal joint); Assist in opposition of the 5th finger toward the thumb

Origin: Hook of hamate and flexor retinaculum

Insertion: Base of proximal phalanx of 5th finger, volar surface

Spinal + Peripheral Nerve Innervation: Ulnar C7 and C8, T1

Opponens Digiti Minimi

Action: Opposition of the 5th finger at the carpometacarpal joint

Origin: Hook of hamate and flexor retinaculum

Insertion: Shaft of 5th metacarpal, ulnar surface

Spinal + Peripheral Nerve Innervation: Ulnar C7 and C8, T1

Palmar Interossei

Action: Adduct the 2nd, 4th, and 5th fingers toward the 3rd finger; Assist to flex the 2nd, 4th, and 5th fingers at the metacarpophalangeal joints; Assist to extend the 2nd, 4th, and 5th fingers at the interphalangeal joints

Origin: Base of 2nd, 4th and 5th metacarpals

Insertion: Base of the proximal phalanx of the related finger and the extensor aponeurosis

Spinal + Peripheral Nerve Innervation: Ulnar C8 and T1

Dorsal Interossei

Action: Abduct the 2nd, 3rd, and 4th fingers at the metacarpophalangeal joints; Assist to flex teh 2nd, 3rd, and 4th fingers at the metacarpophalangeal joints; Assist to extend the 2nd, 3rd, and 4th fingers at the interphalangeal joints

Origin: Adjacent sides of all metacarpals

Insertion: Base of the proximal phalanx of the 2nd, 3rd, and 4th fingers and the extensor aponeurosis

Spinal + Peripheral Nerve Innervation: Ulnar C8 and T1

Adductor Pollicis

Action: Adduct the thumb (carpometacarpal and metacarpophalangeal joints); Assist to flex the thumb (metacarpophalangeal joint)

Origin: Capitate, 2nd and 3rd metacarpals

Insertion: Base of proximal phalanx of thumb

Spinal + Peripheral Nerve INnveration: Ulnar C8 and T1

Lumbricals

Action: Extend the 2nd through 5th fingers at the interphalangeal joints; Flex the 2nd through 5th fingers at the metacarpophalangeal joints

Origin: Surfaces of the flexor digitorum profundus tendons

Insertion: Extensor aponeurosis on dorsal surface of phalanges

Spinal + Peripheral Nerve Innervation: 2nd and 3rd fingers: Median C6 to C8, T1; 4th and 5th fingers: Ulnar C7 and C8, T1