The ulnar head prosthesis: Indications and limitations

The ulnar head prosthesis (UHP) has been developed to restore function and stability of the distal radioulnar joint (DRUJ) following failed resection arthroplasties of the DRUJ. Several clinical studies have demonstrated the reliability of the procedure and the favorable results have been maintained over 10 years. Therefore, the method has to be considered not only as a salvage procedure following resection arthroplasties but also as a valuable alternative in the primary treatment of posttraumatic or degenerative arthritis of the DRUJ. Stability of the prosthesis is achieved by means of an ulnar based soft tissue flap. Insufficiency of the soft tissue structures has to be considered a contraindication for the procedure. This may be the case in patients who have had several previous operations on the DRUJ or in a number of patients with rheumatoid arthritis where these stabilizing structures are weak. Therefore, whilst hemiresection arthroplasty of the DRUJ remains the primary treatment option for rheumatoid patients, treatment of secondary instability using the UHP can only be considered if the soft tissues are amenable to reconstruction to allow stabilization of the prosthesis. Other contraindications consist of insufficient bone quality to allow osseous integration of the prosthesis and a previous Essex-Lopresti injury.