Unusual origin of Abductor digiti minimi – A Case Report

Compression neuropthies of median and ulnar nerves are of frequent occurrence and result from narrowing of carpal tunnel and/or Guyon’s canal by space occupying lesions or anomalous or hypertrophied muscles on anterior aspect of wrist. During routine anatomical dissection of right upper limb of a 52-year-old male cadaver, an unusual origin and course of Abductor digitiminimi (ADM) muscle was observed. In the present report the variant muscle is described and the possibility of both ulnar nerve entrapment and ulnar artery thrombosis though it is of rare occurrence is suggested. The Abductor digiti minimi muscle on right side is found taking origin from radial side of palmar carpal ligament and passing superficial to flexor retinaculum and crossing superficial to ulnar nerve and vessels. Few muscle fibres are attached to piso-hamate ligament and inserted on the medial side of base of proximal phalanx of little finger.