An unusual flexor of the little finger and ulnar nerve entrapment: a case report

Variations in the flexor digitorum superficialis are rare. We report an unusual digastric flexor muscle of the little finger arising independently from the ulnar collateral ligament and right coronoid process of ulna. This digastric muscle was on the medial side of the flexor digitorum superficialis muscle, and got inserted into the middle phalanx of the little finger. The tendon of flexor digitorum superficialis to the little finger was absent. In addition, the ulnar nerve was making a peculiar course, where it entered the forearm between the flexor digitorum superficialis muscle and the digastric muscle. The clinical significance and probable complication caused by the variants are discussed.