Posterior Forearm Muscles Flashcards
Brachioradialis
O: Proximal 2/3 of lateral supracondylar ridge of humerus
I: Lateral surface of distal end of Radius proximal to the Styloid Process
N: Radial Nerve (C5, C6, C7)
A: Flexes forearm, pronation to neutral from supination, supination to neutral from pronation
Extensor Carpi Radialis Longus
O: Inferior 1/3 of lateral supracondylar ridge of Humerus
I: Dorsal Surface of Base of 2nd Metacarpal bone
N: Radial Nerve (C6, C7)
A: Extend and abduct hand at wrist joint; stabilizes hand during fist clenching
Extensor Carpi Radialis Brevis
O: Lateral epicondyle of Humerus (Radial Collateral Ligament)
I: Dorsal Surface base of 3rd Metacarpal bone
N: Deep branch of Radial Nerve (C7, C8)
A: Etend and abduct hand at wrist joint
Extensor Digitorum
O: Lateral Epicondyle of Humerous
I: Extensor expansion of medial 4 digits
N: Deep branch of the Radial Nerve (C7, C8)
A: Weakly Extends medial 4 Digits at MCP and IP joints; extends at wrist joint
Extensor Digiti Minimi
O: Lateral Epicondyle of Humerus
I: Extensor expansion of 5th digit
N: Deep branch of Radial Nerve (C7, C8)
A: Extends 5th Digit at MCP and IP Joints
Extensor Carpi Ulnaris
O: Lateral Epicondyle of Humerus and Posterior border of Middle Ulna
I: Dorsal aspect of base of 5th Metacarpal
N: Deep branch of RADIAL Nerve (C7, C8)
A: Extends and adducts hand at wrist joint; stabilizes hand during fist clenching
Anconeus
O: Lateral Epicondyle of Humerus
I: Lateral Surface of Olecranon and Superior part of Posterior surface of Ulna
N: Radial Nerve (C7, C8, T1)
A: Assists Triceps in extending forearm; Stabilizes elbow joint; Abducts Ulna during Pronation
Supinator
O: Radial Collateral and Anular Ligaments, Supinator Fossa, Crest of Ulna, and Lateral Epicondyle of Humerus
I: Lateral, Anterior, and Posterior surfaces of proximal 1/3 of Radius
N: Deep branch of the Radial Nerve (C7, C8)
A: Supinates forearm
Abductor Pollicis Longus
O: Posterior surfaces of proximal Ulna, Radius, and Interosseous Membrane
I: Base of 1st Metacarpal
N: Posterior Interosseous Nerve (C7, C8)
A: Abducts thumb and extends it at CMC joint
Extensor Pollicis Brevis
O: Posterior Surface of distal 1/3 Radius and Interosseous Membrane
I: Dorsal aspect, base of proximal phalanx of thumb
N: Posterior Interosseous Nerve (C7, C8)
A: Extends proximal phalanx of them at CMC and MCP joint
Extensor Pollicis Longus
O: Posterior surface of middle 1/3 of Ulna and Interosseous Membrane
I: Dorsal aspect, base of distal phalanx of thumb
N: Posterior Interosseous Nerve (C7, C8)
A: Extends distal phalanx of thumb at MCP and IP joints
Extensor Indicis
O: Posterior surface of Ulna and Interosseous Membrane
I: Extensor Expansion of 2nd Digit
N: Posterior Interosseous Nerve (C7, C8)
A: Extends 2nd Digit and helps to extend hand at wrist
