Unusual variation of the extensor indicis muscle tendon

There are numerous reports regarding the variations of the extensor muscles. The present report is on the unusual variation of the extensor indicis muscle. The extensor indicis presented two tendons, one of which is inserted into the ulnar aspect of the dorsal digital expansion of the index finger. While the other tendon –especially in the left upper limb– was inserted into the dorsal part of the capsule of the metacarpophalangeal joint of the middle finger and also few tendinous fibers were merging with the dorsal expansion of the middle finger. The same variation was found in the right upper limb, but the insertion was to the dorsal digital expansion of the index and middle fingers and no attachment to the capsule was noticed.