English

Abstract

It begins 1 cm distal to the elbow joint, at the level of neck of radius. It runs medial to the brachioradialis throughout its course in the forearm. Just above the wrist, it is palpable between the flexor carpi radialis medially and anterior border of radius laterally. It then turns posterolaterally round the wrist superficial to the lateral ligament of the wrist and deep to the abductor pollicis longus and extensor pollicis brevis muscles. It crosses the scaphoid and trapezium bones and just before it passes between the heads of the first dorsal interosseous it is crossed by the tendon of the extensor pollicis longus muscle. Between the extensor muscles of the thumb, it is crossed by the cephalic vein and digital branches of the radial nerve which supply the thumb and index finger. It passes between the two heads of the first dorsal interosseous muscle and enters the palm 1 . The common mode of termination of the RA is by forming the deep palmar arch. Although variations in the origin of the RA are common, with an incidence of 15% 2 , variations in the course are rare, with an incidence of only 0.52% 3 . For radiological, surgical and routine patient care purpose, precise knowledge of the course of the RA and its relation to adjacent structures in the distal part of the forearm and wrist is of great importance. We present a rare case of ‘very superficial course’ of the RA and discuss its clinical and surgical importance.