Abstract
The neural component of the peripheral nerve consists of the axons and their associated Schwann cells. At the wrist, the median nerve lies lateral to sublimis tendons between the flexor carpi radialis and the palmaris longus. The ulnar nerve arises from the medial cord beneath the pectoralis minor. At the elbow, the ulnar nerve travels in the ulnar groove posterior to the medial epicondyle. The radial nerve originates as a terminal branch of the posterior cord of the brachial plexus, approximately at the level of the coracoid process. Initially lateral to the vessels in the upper popliteal fossa, the tibial nerve crosses to the medial aspect caudally. The common peroneal nerve innervates the muscle of dorsiflexion, or extension of the foot. It is most commonly injured by athletic or automobile accidents related to trauma to the lateral aspect of the head of the fibula.