HN210 Study Guide - Midterm Guide: Radial Nerve, Brachioradialis, Extensor Carpi Muscle
Document Summary
Are in the posterior compartment of the forearm and are all innervated by the radial nerve. Muscles that extend/abduct/adduct the hand at the wrist joint: extensor carpi radialis longus (ecrl), extensor carpi radialis brevis (ecrb), and extensor carpi ulnaris (ecu) Muscles that extend the medial 4 digits: extensor digitorum, extensor indicis, and extensor digiti minimi (edm) Muscles that extend or abduct the thumb: abductor pollicis longus (apl), extensor pollicis brevis (epb) and extensor pollicis longus (epl) Tendons are held in place by extensor retinaculum. 4 superficial extensors are attached proximally by a commonn extensor tendon to lateral epicondyle: extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi (edm), 2 superficial extensors that are attached to the lateral supracondylar ridge: extensor carpi radialis longus, brachioradialis. Origin: lateral supracondylar ridge of the humerus. Insertion: dorsal aspect of base of 2nd metacarpal. Insertion: dorsal aspect of base of 3rd metacarpal. Action: extend & abduct wrist joint: active during wrist fist clenching.
