Brachioradialis

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Brachioradial muscle
Anterior view of muscles of the left forearm with Brachioradialis shown in blue.
Cross-section through the middle of the forearm. (Brachioradialis labeled at center left, sixth from the top.)
Latin	musculus brachioradialis
Gray's	subject #125 451
Origin	Lateral supracondylar ridge of the humerus
Insertion	Distal radius (Radial styloid process)
Artery:	radial recurrent artery
Nerve:	radial nerve
Action:	Flexion of forearm
Dorlands /Elsevier	m_22/12548506

Brachioradialis is a muscle of the forearm that acts to flex the forearm at the elbow. It is also capable of both pronation and supination, depending on the position of the forearm. It is attached to the distal styloid process of the radius and the lateral supracondylar ridge of the humerus.

Contents 1 Action 2 Innervation 3 Additional images 4 External links

[edit] Action

Brachioradialis flexes the forearm at the elbow. When the forearm is pronated, the brachioradialis tends to supinate as it flexes. In a supinated position, it tends to pronate as it flexes.

The brachioradialis is a stronger elbow flexor when the forearm is in a midposition between supination and pronation at the radioulnar joint. When pronated, the brachioradialis is more active during elbow flexion since the biceps brachii is in a mechanical disadvantage.

[edit] Innervation

Despite the bulk of the muscle body being visible from the anterior aspect of the forearm, the brachioradialis is a posterior compartment muscle and consequently is innervated by the radial nerve. Of the muscles that receive innervation from the radial nerve, it is one of only four that receive input directly from the radial nerve. The other three are the triceps, anconeus, and extensor carpi radialis longus. (All other posterior compartment muscles that receive radial innervation are supplied by the deep branch of the radial nerve.)

[edit] Additional images

Left humerus. Anterior view.	Bones of left forearm. Anterior aspect.	Front of the left forearm. Superficial muscles.	Posterior surface of the forearm. Superficial muscles.
The brachial artery.	The radial and ulnar arteries.	Ulnar and radial arteries. Deep view.	Nerves of the left upper extremity.

[edit] External links

• LUC brds
• UWASH brachioradialis
• SUNY Figs 07:01-09 - "Transverse section through the left arm just proximal to the elbow."
• SUNY Figs 07:03-07 - "Superficial muscles of the anterior (flexor) compartment of the left forearm."
• SUNY Figs 09:02-02 - "Superficial muscles of the posterior (extensor) compartment of the left forearm."
• Norman/Georgetown lesson5musofpostforearm

v • d • e List of muscles of upper limbs VERTEBRAL COLUMN trapezius - latissimus dorsi - rhomboid (major, minor) - levator scapulae THORACIC WALLS pectoralis major - pectoralis minor - subclavius - serratus anterior SHOULDER deltoid - rotator cuff (supraspinatus, infraspinatus, teres minor, subscapularis) - teres major ARM anterior compartment: coracobrachialis - biceps brachii - brachialis posterior compartment: triceps brachii - anconeus FOREARM anterior compartment: superf. - pronator teres - palmaris longus - flexor carpi radialis - flexor carpi ulnaris - flexor digitorum superficialis anterior compartment: deep - pronator quadratus - flexor digitorum profundus - flexor pollicis longus posterior compartment: superf. - mobile wad (brachioradialis, extensor carpi radialis longus and brevis) - extensor digitorum, - extensor digiti minimi - extensor carpi ulnaris posterior compartment: deep - supinator - anatomical snuff box (abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus) - extensor indicis HAND lateral volar - thenar (opponens pollicis, flexor pollicis brevis, abductor pollicis brevis) - adductor pollicis medial volar - hypothenar (opponens digiti minimi, flexor digiti minimi brevis, abductor minimi digiti) - palmaris brevis intermediate - lumbrical - interossei (dorsal, palmar)