A Rare Variation of Extensor Indices Muscle – A Case Report

Abstract

Abstract The Extensor Indicis muscle is one among the deep muscles of the extensor compartment of the forearm which takes origin from the Posterior surface of the shaft of the ulna below the origin of the extensor pollicislongus, and from the Inter-osseous membrane. It gets inserted close to the head of second metacarpal bone joining with the index tendon of extensor digitorum on its ulnar side and enters the formation of dorsal digital expansion of the index finger. This muscle helps in the Extension of the index finger and also to extend the wrist. During our routine dissection for 1 st BAMS students, in the dissection hall of KAHER’s Shri B.M. Kankanawadi Ayurveda Mahavidyalaya, Belagavi, of a 55 year old male cadaver, variation in the origin of Extensor Indicis muscle was observed. The extensor Indicis muscle was found arising from the Lunate carpal bone and Dorsal Radiocarpal ligament andit further continued as short belly and had its distal attachment on the proximal phalanx of the index finger. Abnormal origin of Extensor IndicisMuscle may possibly be associated with pain and swelling at the back of the hand. This pain may be misinterpreted with other clinical conditions like synovial cyst and ganglion. Knowledge of such rare variations isuseful to clinician and surgeons for therapeutic and surgical procedures.