Arm and Hand Muscles Flashcards
Origin of Biceps brachii
Long head-supraglenoid tubercle of scapula; short head-apex of coracoid process
Insertion of Biceps brachii
Tuberosity of radius
Innervation of Biceps brachii
Musculocutaneous nerve [C5, C6]
Function of Biceps brachii
Powerful flexor of the forearm at the elbow joint and supinator of the forearm; accessory flexor of the arm at the glenohumeral joint
Origin of Brachialis
Anterior aspect of humerus (medial and lateral surfaces) and adjacent intermuscular septae
Insertion of Brachialis
Tuberosity of the ulna
Innervation of Brachialis
Musculocutaneous nerve [C5, C6]
Function of Brachialis
Powerful flexor of the forearm at the elbow joint
Origin of Coracobrachialis
Apex of coracoid process
Insertion of Coracobrachialis
Linear roughening on midshaft of humerus on medial side
Innervation of Coracobrachialis
Musculocutaneous nerve [C5, C6, C7]
Function of Coracobrachialis
Flexor of the arm at the glenohumeral joint
Origin of Triceps brachii
Long head-infraglenoid tubercle of scapula; medial head-posterior surface of humerus; lateral head-posterior surface of humerus
Insertion of Triceps brachii
Olecranon
Innervation of Triceps brachii
Radial nerve [C6, C7, C8]
Function of Triceps brachii
Extension of the forearm at the elbow joint. Long head can also extend and adduct the arm at the shoulder joint
Origin of Brachioradialis
Proximal part of lateral supraepicondylar ridge of humerus and adjacent intermuscular septum
Insertion of Brachioradialis
Lateral surface of distal end of radius
Innervation of Brachioradialis
Radial nerve [C5, C6]
Function of Brachioradialis
Accessory flexor of elbow joint when forearm is midpronated
Origin of Pronator teres
Humeral head-medial epicondyle and adjacent supraepicondylar ridge; ulnar head-medial side of coronoid process
Insertion of Pronator teres
Roughening on lateral surface, midshaft, of radius
Innervation of Pronator teres
Median nerve [C6, C7]
Function of Pronator teres
Pronation
Origin of Pronator quadratus
Linear ridge on distal anterior surface of ulna
Insertion of Pronator quadratus
Distal anterior surface of radius
Innervation of Pronator quadratus
Median nerve [C7, C8]
Function of Pronator quadratus
Pronation
Origin of Supinator
Superficial part-lateral epicondyle of humerus, radial collateral and anular ligaments; deep part-supinator crest of the ulna
Insertion of Supinator
Lateral surface of radius superior to the anterior oblique line
Innervation of Supinator
Posterior interosseous nerve [C6, C7]
Function of Supinator
Supination
Origin of Palmaris longus
Medial epicondyle of humerus
Insertion of Palmaris longus
Palmar aponeurosis of hand
Innervation of Palmaris longus
Median nerve [C7, C8]
Function of Palmaris longus
Flexes wrist joint; because the palmar aponeurosis anchors skin of the hand, contraction of the muscle resists shearing forces when gripping
Origin of Flexor carpi ulnaris
Humeral head-medial epicondyle of humerus; ulnar head-olecranon and posterior border of ulna
Insertion of Flexor carpi ulnaris
Pisiform bone, and then via pisohamate and pisometacarpal ligaments into the hamate and base of metacarpal V
Innervation of Flexor carpi ulnaris
Ulnar nerve [C7, C8, T1]
Function of Flexor carpi ulnaris
Flexes and adducts the wrist joint
Origin of Flexor pollicis longus
Anterior surface of radius and radial half of interosseous membrane
Insertion of Flexor pollicis longus
Palmar surface of base of distal phalanx of thumb
Innervation of Flexor pollicis longus
Median nerve (anterior interosseous nerve) [C7, C8]
Function of Flexor pollicis longus
Flexes interphalangeal joint of the thumb; can also flex metacarpophalangeal joint of the thumb
Origin of Flexor digitorum superficialis
Humero-ulnar head-medial epicondyle of humerus and adjacent margin of coronoid process; radial head-oblique line of radius
Insertion of Flexor digitorum superficialis
Four tendons, which attach to the palmar surfaces of the middle phalanges of the index, middle, ring, and little fingers
Innervation of Flexor digitorum superficialis
Median nerve [C8, T1]
Function of Flexor digitorum superficialis
Flexes proximal interphalangeal joints of the index, middle, ring, and little fingers; can also flex metacarpophalangeal joints of the same fingers and the wrist joint
Origin of Flexor digitorum profundus
Anterior and medial surfaces of ulna and anterior medial half of interosseous membrane
Insertion of Flexor digitorum profundus
Four tendons, which attach to the palmar surfaces of the distal phalanges of the index, middle, ring, and little fingers
Innervation of Flexor digitorum profundus
Lateral half by median nerve (anterior interosseous nerve); medial half by ulnar nerve [C8, T1]
Function of Flexor digitorum profundus
Flexes distal interphalangeal joints of the index, middle, ring, and little fingers; can also flex metacarpophalangeal joints of the same fingers and the wrist joint
Origin of Flexor carpi radialis
Medial epicondyle of humerus
Insertion of Flexor carpi radialis
Base of metacarpals II and III
Innervation of Flexor carpi radialis
Median nerve [C6, C7]
Function of Flexor carpi radialis
Flexes and abducts the wrist
Origin of Flexor pollicis brevis
Tubercle of the trapezium and flexor retinaculum
Insertion of Flexor pollicis brevis
Proximal phalanx of the thumb
Innervation of Flexor pollicis brevis
Recurrent branch of median nerve [C8, T1]
Function of Flexor pollicis brevis
Flexes thumb at metacarpophalangeal joint
Origin of Abductor pollicis brevis
Tubercles of scaphoid and trapezium and adjacent flexor retinaculum
Insertion of Abductor pollicis brevis
Proximal phalanx and extensor hood of thumb
Innervation of Abductor pollicis brevis
Recurrent branch of median nerve [C8, T1]
Function of Abductor pollicis brevis
Abducts thumb at metacarpophalangeal joint
Origin of Opponens pollicis
Tubercle of trapezium and flexor retinaculum
Insertion of Opponens pollicis
Lateral margin and adjacent palmar surface of metacarpal I
Innervation of Opponens pollicis
Recurrent branch of median nerve [C8, T1]
Function of Opponens pollicis
Medially rotates thumb
Origin of Abductor digiti minimi
Pisiform, the pisohamate ligament, and tendon of flexor carpi ulnaris
Insertion of Abductor digiti minimi
Proximal phalanx of little finger
Innervation of Abductor digiti minimi
Deep branch of ulnar nerve [C8, T1]
Function of Abductor digiti minimi
Abducts little finger at metacarpophalangeal joint
Origin of Flexor digiti minimi brevis
Hook of the hamate and flexor retinaculum
Insertion of Flexor digiti minimi brevis
Proximal phalanx of little finger
Innervation of Flexor digiti minimi brevis
Deep branch of ulnar nerve [C8, T1]
Function of Flexor digiti minimi brevis
Flexes little finger at metacarpophalangeal joint
Origin of Opponens digiti minimi
Hook of hamate and flexor retinaculum
Insertion of Opponens digiti minimi
Medial aspect of metacarpal V
Innervation of Opponens digiti minimi
Deep branch of ulnar nerve [C8, T1]
Function of Opponens digiti minimi
Laterally rotates metacarpal V
Origin of Palmaris brevis
Palmar aponeurosis and flexor retinaculum
Insertion of Palmaris brevis
Dermis of skin on the medial margin of the hand
Innervation of Palmaris brevis
Superficial branch of the ulnar nerve [C8, T1]
Function of Palmaris brevis
Improves grip
Origin of Extensor carpi radialis longus
Distal part of lateral supraepicondylar ridge of humerus and adjacent intermuscular septum
Insertion of Extensor carpi radialis longus
Dorsal surface of base of metacarpal II
Innervation of Extensor carpi radialis longus
Radial nerve [C6, C7] before division into superficial and deep branches
Function of Extensor carpi radialis longus
Extends and abducts the wrist
Origin of Extensor carpi radialis brevis
Lateral epicondyle of humerus and adjacent intermuscular septum
Insertion of Extensor carpi radialis brevis
Dorsal surface of base of metacarpals II and III
Innervation of Extensor carpi radialis brevis
Deep branch of radial nerve [C7, C8
Function of Extensor carpi radialis brevis
Extends and abducts the wrist
Origin of Extensor carpi ulnaris
Lateral epicondyle of humerus and posterior border of ulna
Insertion of Extensor carpi ulnaris
Tubercle on the base of the medial side of metacarpal V
Innervation of Extensor carpi ulnaris
Posterior interosseous nerve [C7, C8]
Function of Extensor carpi ulnaris
Extends and adducts the wrist
Origin of Extensor digitorum
Lateral epicondyle of humerus and adjacent intermuscular septum and deep fascia
Insertion of Extensor digitorum
Four tendons, which insert via extensor hoods into the dorsal aspects of the bases of the middle and distal phalanges of the index, middle, ring, and little fingers
Innervation of Extensor digitorum
Posterior interosseous nerve [C7, C8]
Function of Extensor digitorum
Extends the index, middle, ring, and little fingers; can also extend the wrist
Origin of Extensor indicis
Posterior surface of ulna (distal to extensor pollicis longus) and adjacent interosseous membrane
Insertion of Extensor indicis
Extensor hood of index finger
Innervation of Extensor indicis
Posterior interosseous nerve [C7, C8]
Function of Extensor indicis
Extends index finger
Origin of Extensor digiti minimi
Lateral epicondyle of humerus and adjacent intermuscular septum together with extensor digitorum
Insertion of Extensor digiti minimi
Extensor hood of the little finger
Innervation of Extensor digiti minimi
Posterior interosseous nerve [C7, C8]
Function of Extensor digiti minimi
Extends the little finger
Origin of Extensor pollicis longus
Posterior surface of radius (distal to abductor pollicis longus) and the adjacent interosseous membrane
Insertion of Extensor pollicis brevis
Dorsal surface of base of proximal phalanx of the thumb
Innervation of Extensor pollicis brevis
Posterior interosseous nerve [C7, C8]
Function of Extensor pollicis brevis
Extends metacarpophalangeal joint of the thumb; can also extend the carpometacarpal joint of the thumb
Origin of Abductor pollicis longus
Posterior surfaces of ulna and radius (distal to the attachments of supinator and anconeus), and intervening interosseous membrane
Insertion of Abductor pollicis longus
Lateral side of base of metacarpal I
Innervation of Abductor pollicis longus
Posterior interosseous nerve [C7, C8]
Function of Abductor pollicis longus
Abducts carpometacarpal joint of thumb; accessory extensor of the thumb
Origin of Dorsal interossei (four muscles)
Adjacent sides of metacarpals
Insertion of Dorsal interossei (four muscles)
Extensor hood and base of proximal phalanges of index, middle, and ring fingers
Innervation of Dorsal interossei (four muscles)
Deep branch of ulnar nerve [C8, T1]
Function of Dorsal interossei (four muscles)
Abduction of index, middle, and ring fingers at the metacarpophalangeal joints
Origin of Palmar interossei (four muscles)
Sides of metacarpals
Insertion of Palmar interossei (four muscles)
Extensor hoods of the thumb, index, ring, and little fingers and the proximal phalanx of thumb
Innervation of Palmar interossei (four muscles)
Deep branch of ulnar nerve [C8, T1]
Function of Palmar interossei (four muscles)
Adduction of the thumb, index, ring, and little fingers at the metacarpophalangeal joints
Origin of Lumbricals (four muscles)
Tendons of flexor digitorum profundus
Insertion of Lumbricals (four muscles)
Extensor hoods of index, ring, middle, and little fingers
Innervation of Lumbricals (four muscles)
Medial two by the deep branch of the ulnar nerve; lateral two by digital branches of the median nerve
Function of Lumbricals (four muscles)
Flex metacarpophalangeal joints while extending interphalangeal joints
Origin of Adductor pollicis
Transverse head-metacarpal III; oblique head-capitate and bases of metacarpals II and III
Insertion of Adductor pollicis
Base of proximal phalanx and extensor hood of thumb
Innervation of Adductor pollicis
Deep branch of ulnar nerve [C8, T1]
Function of Adductor pollicis
Adducts thumb
Extensors of Elbow Joint
Triceps brachii Extensor capri ulnaris Extensor carpi radialis brevis Extensor digitorum Extensor digiti minimi Supinator (superficial part)
Flexiors of Elbow Joint
Biceps brachii Brachialis (most powerful) Brachioradialis Common flexor group Pronator Teres Flexor carpi radialis Palmaris longus Flexor carpi ulnaris Flexor digitorum superficialias
Suppination of Forearm
Biceps brachii
Suppinator
Pronator of Forearm
Pronator teres
Pronator quadratus
Flexors at Radiocarpal Joint
- Palmaris longus
- Flexor carpi ulnaris
- Flexor carpi radialis
- Flexor digitorum superficialis
- Flexor digitorum profundus
Extensors at Radiocarpal Joint
- Extensor carpi radialis longus
- Extensor carpi radialis brevis
- Extensor carpi ulnaris
- Extensor digitorum
Muscles for Radial Deviation (Abduction) at Radiocarpal Joint
- Flexor carpi radialis
- Extensor carpi radialis longus
- Extensor carpi radialis brevis
Muscles of Ulnar Deviation (Adduction) at Radiocarpal Joint
Flexor carpi ulnaris
Extensor carpi ulnaris
Flexor at IP Joint
Flexor pollicis longus
Extensor at IP Joint
Extensor pollicis longus
Flexors at MCP Joint
Flexor pollicis longus
Flexor pollicis brevis
Origin of Deltoid
Inferior edge of the crest of the spine of the scapula, lateral margin of the acromion, anterior border of lateral one-third of clavicle
Insertion of Deltoid
Deltoid tuberosity of humerus
Innervation of Deltoid
Axillary nerve [C5, C6]
Function of Deltoid
Major abductor of arm (abducts arm beyond initial 15° done by supraspinatus); clavicular fibers assist in flexing the arm; posterior fibers assist in extending the arm