[Outcome after Implantation of the Aptis Total Distal Radioulnar Joint Replacement Prosthesis].

BACKGROUND: To date, the Aptis distal radioulnar joint (DRUJ) prosthesis by Scheker is the only total, bipolar prosthesis available. In the literature, only few data exist concerning the prosthesis and its surgical technique. Aim of the present study was the evaluation of the medium-term clinical and radiological outcome following implantation of the Aptis DRUJ prosthesis.

METHODS AND PATIENTS: 5 patients (4 women and 1 man) with mean age of 40.2 (30-65) years underwent secondary implantation of the Aptisprosthesis between February 2006 and May 2013. The average date of the follow-up was after 36 (24-48) months. Besides the complications, the wrist range of motion (ROM) and the strength in grip were measured. The quality of pain was determined using a visual analogue pain scale from 0-10. In follow-up X-ray controls, bone resorption and bony abnormalities were evaluated. The DASH score as well as the postoperative subjective satisfaction of the patients were recorded.

RESULTS: No patient required removal of the prosthesis. Only 1 patient underwent secondary surgery in which debridement of the screw tip over the radius was required. The postoperative range of motion in pronation and supination was measured with 78 (70-90)° and 82 (70-90)°. The average grip strength amounted to 29 (24-32) kg. This represented 85 (76-100)% of the value of the contralateral side. Postoperative pain symptoms on the visual analogue pain scale were measured with 0 points at rest and with 1.2 (0-2) points under strain. Radiological evaluation showed bone resorption at the radial peg in 2 patients, but without evidence of implant loosening. The DASH score was recorded with 37 (13-75) points. All patients were satisfied or very satisfied after the surgical treatment.

CONCLUSION: The Aptis prosthesis is a safe and efficient treatment option for previously failed surgery of the DRUJ.