Possible entrapment of sensory branch of radial nerve by split brachioradialis tendon: An anatomical variation

Entrapment of superficial branch of radial nerve is a rare clinical condition where it can be compressed at any point along its course in the forearm. The course of superficial branch of radial nerve between two slips of the split brachioradialis tendon may form a potential site of entrapment for the nerve. The incidence of such entrapment is rarely reported in the literature. Here we report a case of split brachioradialis tendon forming a site of entrapment for the sensory branch of radial nerve. During regular dissection classes, we observed the split brachioradialis tendon at about 7 cm proximal to the radial styloid process, in a male cadaver of South Indian origin. The additional slip of the tendon was small and it firmly attached to the muscle fibers of the abductor pollicis longus. The sensory branch of radial nerve passed through the narrow interval formed by the two slips of brachioradialis split tendon, before becoming subcutaneous structure. The knowledge about the anatomical variations of split brachioradialis tendon and the position and possible attachments of additional slips is of clinical importance during surgical decompression of Wartenberg’s syndrome.