Extensor Carpi Radialis Brevis
Original Editor Uchechukwu Chukwuemeka
Top Contributors - Uchechukwu Chukwuemeka, Kim Jackson and Aya Alhindi
Original Editor -
Top Contributors - Uchechukwu Chukwuemeka, Kim Jackson and Aya Alhindi
Description[edit | edit source]
Extensor carpi radialis brevis is a short muscle situated underneath the extensor carpi radialis longus with both muscles sharing a common synovial sheath. It is an extensor muscle located at superficially at the posterior compartment of the forearm.
Origin[edit | edit source]
It originates from the common extensor tendon with extensor carpi ulnaris, extensor digiti minimi, and extensor digitorum at the Lateral epicondyle of humerus together.
Insertion[edit | edit source]
It attaches at dorsal surface of the base of the 3rd metacarpal
Nerve[edit | edit source]
ECRB is innervated by the deep branch of radial nerve (7th and 8th cervical nerve root) before the nerve courses through the two heads of the supinator muscle
Artery[edit | edit source]
vascular supply primarily from the radial artery, with further supply from the radial collateral branch off of profunda brachii. From the radial artery, the extensor carpi radialis brevis first receives a branch from the radial recurrent artery. Then, further down the forearm, the muscle gets an additional branch from the radial artery.
Function[edit | edit source]
ECRB extends and abducts the wrist
Clinical relevance[edit | edit source]
Patients having pain on the lateral aspect of the elbow with or without loss of grip strength that is aggravated with activity will most likely have extensor carpi radialis brevis muscle affectation in lateral epicondylitis.
In cases of radial nerve compromise proximal to its division to deep and superficial branches at the cubital fossa, then some functional loss of wrist and digits extension will present.
Assessment[edit | edit source]
With the hand in pronation, the ECRB muscle can be palpated during extension and abduction of the wrist against resistance.
