Unusual Topography of Posterior Antebrachial Musculature in the First Osseofibrous Compartment of Wrist- Clinicomorphological Appraisal Topografía Inusual de la Musculatura Antebraquial Posterior en el Primer Compartimento

SUMMARY: Anatomical variations of abductor pollicis longus and extensor pollicis brevis are important in clinical assessment of diseased and traumatized hand. The present case reports an unusual fusion of muscle bellies of abductor pollicis longus and extensor pollicis brevis with two separate tendons of insertion, the medial tendon inserted into the base of first metacarpal and the lateral tendon into the abductor pollicis brevis muscle. Knowledge of such anatomical variations is of utmost importance in the management of De Quervain’s disease and reconstructive surgeries of hand. KEY WORDS: Abductor pollicis longus; Extensor pollicis brevis; De Quervain’s syndrome; Variations