Extensor digitorum brevis manus - its incidence and clinical insight

Abstract

Background and aims: Extensor digitorum brevis manus is an accessory muscle on the dorsum of the hand. It lies in the fourth extensor compartment of the wrist. Its occurrence is relatively rare. Incidence of this muscle is 4% in the general population. Presence of this muscle is usually asymptomatic but rarely it may produce painful swelling which can be misdiagnosed as lipoma or ganglion or synovial cyst. Aim of the present study was to find out the incidence of extensor digitorum brevis manus muscle in Indian cadavers. Material and Methods: Study was conducted on 64 human hands of adult Indian cadavers of unknown age and sex in the department of anatomy. A longitudinal incision was placed on the dorsum of hand along the axis of middle finger, skin flaps were raised both on radial and ulnar side. A transverse incision was taken at metacarpo-phalangeal joints from second to fifth fingers. Dorsum of each hand was dissected carefully to see the presence of extensor digitorum brevis manus. Results: We found extensor digitorum brevis manus muscle in 3 hands [rt.-1; It. - 2] out of 64, i.e. 4.68%. Conclusion: Anatomical knowledge of this muscle present in the extensor compartment may be helpful in planning tendon transfer or graft surgeries Therefore, the knowledge of these variant muscles may be important.

Keywords

• extensor digitorum brevis manus
• dorsum of the hand
• extensor compartment
• tendon transfer