An anomalous extensor indicis muscle.

1. A case is described in which the extensor indicis tendon was replaced by a short muscle arising from the soft tissues on the dorsum of the wrist. 2. The patient complained of pain in the hand after heavy use. This was considered to be due to constriction of the muscle by the extensor retinaculum. Division of the retinaculum was followed by a considerable improvement in his symptoms.