Exercise 12: Muscles Acting on the Hand

Vocabulary flashcards covering the origin, insertion, action, and innervation of anterior and posterior muscles acting on the hand from Table 12.2.

Palmaris longus

An anterior muscle acting on the hand. Origin: Medial epicondyle of humerus. Insertion: Palmar fascia. Action: Flexes hand.

Flexor carpi radialis

An anterior muscle acting on the hand. Origin: Medial epicondyle of humerus. Insertion: Metacarpals 2 and 3. Action: Flexes and abducts hand.

Flexor carpi ulnaris

An anterior muscle acting on the hand. Origin: Medial epicondyle of humerus and ulna. Insertion: Pisiform, hamate, metacarpal 5. Action: Flexes and adducts hand.

Flexor digitorum superficialis

An anterior muscle acting on the hand. Origin: Medial epicondyle of humerus, coronoid process of ulna, proximal radius. Insertion: Middle phalanges of digits 2-5. Action: Flexes proximal and middle phalanges 2-5, flexes hand.

Flexor digitorum profundus

An anterior muscle acting on the hand. Origin: Ulna, interosseus membrane. Insertion: Distal phalanges of digits 2-5. Action: Flexes phalanges, flexes hand.

Flexor pollicis longus

An anterior muscle acting on the hand. Origin: Anterior portion of radius and interosseus membrane. Insertion: Distal phalanx of pollex (thumb). Action: Flexes thumb and hand.

Flexor pollicis brevis

An anterior muscle acting on the hand. Origin: Trapezium. Insertion: Proximal phalanx of digit 1. Action: Flexes thumb.

Abductor pollicis brevis

An anterior muscle acting on the hand. Origin: Scaphoid, trapezium. Insertion: Proximal phalanx of digit 1. Action: Abducts thumb.

Opponens pollicis

An anterior muscle acting on the hand. Origin: Trapezium. Insertion: Metacarpal 1. Action: Opposes thumb.

Abductor digiti minimi

An anterior muscle acting on the hand. Origin: Pisiform. Insertion: Proximal phalanx of digit 5. Action: Abducts digit 5.

Flexor digiti minimi brevis

An anterior muscle acting on the hand. Origin: Hamulus of hamate. Insertion: Proximal phalanx of digit 5. Action: Flexes digit 5.

Opponens digiti minimi

An anterior muscle acting on the hand. Origin: Hamulus of hamate. Insertion: Metacarpal 5. Action: Opposes digit 5.

Extensor carpi radialis longus

A posterior muscle acting on the hand. Origin: Lateral supracondylar ridge of humerus. Insertion: Metacarpal 2. Action: Extends and abducts hand.

Extensor carpi radialis brevis

A posterior muscle acting on the hand. Origin: Lateral epicondyle of humerus. Insertion: Metacarpal 3. Action: Extends and abducts hand.

Extensor carpi ulnaris

A posterior muscle acting on the hand. Origin: Lateral epicondyle of humerus, proximal ulna. Insertion: Metacarpal 5. Action: Extends and adducts hand.

Extensor digitorum

A posterior muscle acting on the hand. Origin: Lateral epicondyle of humerus. Insertion: Middle and distal phalanges of digits 2-5. Action: Extends phalanges 2-5, extends hand.

Abductor pollicis longus

A posterior muscle acting on the hand. Origin: Posterior radius and ulna, interosseus membrane. Insertion: Metacarpal 1. Action: Abducts and extends thumb, abducts hand.

Extensor pollicis longus and brevis

Posterior muscle(s) acting on the hand. Origin: Posterior radius and ulna, interosseus membrane. Insertion: Proximal and distal phalanges of pollex (thumb). Action: Extends thumb.