Radial nerve injury

The radial nerve is close to the backbone in the middle and lower 1/3 of the humerus, where the radial nerve is vulnerable to injury when the humerus is broken. Excessive callus growth and anterior dislocation of the radial head can compress the radial nerve. This nerve can also be injured by accidental surgery. The radial nerve is composed of the fibers of the neck 5-8 and the thoracic 1 nerve root, which continues the posterior tract of the brachial plexus. In the upper arm, after the radial nerve emerges from the axilla, it follows the deep brachial artery from the inside of the upper arm through the long and medial head of the triceps to the back of the upper arm, and then passes through the radial nerve groove of the humerus between the internal and lateral heads of the triceps When descending to the upper and outer sides of the elbow, it is divided into shallow and deep branches and then enters the forearm. The radial nerve branches in the upper arm in succession and innervates the triceps brachii, radial brachialis, and radial long wrist extensors. In the forearm, the superficial branch is located on the deep side of the brachioradialis and accompanies the radial artery. The superficial branch is mainly sensory nerve fibers, which are distributed on the radial skin on the back of the hand and on the back of the two and a half fingers on the radial side, but do not include the skin on the back of the distal second segment. The deep branch, also known as the dorsal interosseous nerve, passes from the deep side of the brachioradialis to the back of the forearm, passes through the supinator muscle, and descends between the superficial and deep muscles. The muscles dominated by successive branches are: radial short wrist extensors and supinator muscles above the supinator muscle; total digital extensors, little finger extensors, ulnar wrist extensors, and thumb Long abductors, short extensor hallucis, and extensor extensors.