In four cases, proximal radioulnar synostosis developed as a complication of distal biceps tendon reattachment through a two-incision technique. The synostosis was excised in all four cases but recurred in two. In each case, the initial reattachment exposed the bicipital tuberosity of the radius anteriorly and exposed the ulna extraperiosteally through a second incision along its subcutaneous border. This two-incision approach may place the patient at risk for synostosis. If two incisions are to be used for distal biceps tendon reattachment, then a limited muscle-splitting approach through the extensor muscle mass, which avoids exposure of the ulna, may be preferable.