The brachialis muscle is the main flexor that the elbow. This muscle is situated in the anterior compartment that the arm along with the Biceps brachii and coracobrachialis.

Origin

Distal anterior aspect of the humerus, deep come the biceps brachii.

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Insertion

Coronoid procedure and the ulnar tuberosity.<2>

Nerve

The brachialis muscle is innervated through the musculocutaneous nerve and components of the radial nerve. The radial nerve descends in the groove in between the brachialis and brachioradialis muscles, over the elbow. That the muscle in the anterior compartment, the biceps brachii and the brachialis room innervated through C5 and C6 nerve roots.<3>


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Artery

Muscular branches the brachial artery, recurrent radial artery.<2>

Function

The brachialis muscle has a big cross sectional area, providing it with more strength than the biceps brachii and the coracobrachialis.<4> In stimulate to isolate the brachialis muscle the forearm requirements to be in pronation, due to the biceps brachii\"s duty as a supinator and flexor.<4> by pronating the forearm the biceps is put right into a mechanical disadvantage.


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Clinical relevance

The brachialis muscle have the right to be typically injured by repetitive forceful contractions or muscular contractions v the arm in hyperextension. This is commonly seen in climbers, due to the pronation that the hand and the expanded started position.<5> Physical activity that involve a most pull ups, curls, and rope climb can additionally initiate brachialis muscle pain.<6> A strain to the brachialis tendon can likewise cause a patience to existing with lacking elbow extension as result of painful end-range extending of the tendon. Due to the location of the pain, medial epicondylitis and also lateral epicondylitis should additionally be evaluated.

The brachialis acts as the floor the the cubital fossa<3>, and is component of the radial tunnel. It may be implicated in Erb\"s palsy if the Brachial plexus becomes injured, bring about elbow flexion weakness.

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Assessment

To evaluate the strength of the brachialis ar the elbow in ~ 90 levels of flexion through the forearm fully pronated. Then have the patient stand up to an inferior pressure placed on the distal forearm.<7>