gms | German Medical Science

Objectives/Interrogation: Post-traumatic, arthritic or degenerative destruction of the midcarpal and radiocarpal joint is difficult to treat. An arthroplasty with a free interposition pyrocarbon implant, Amandys ®, is proposed for the treatment of extensive destruction of midcarpal and radiocarpal joints. The purpose of this study was to evaluate the clinical and patient-rated outcome.

Methods: From October 2014 to March 2018, 17 Amandys ® interposition arthroplasties were performed. Patients were assessed preoperatively (baseline), at 3, 6, 12 and 24 months after surgery. Radiographs, range of motion and grip strength were evaluated. In addition, patients rated their pain using a numeric rating scale (NRS) as well as function and overall assessment of their condition and satisfaction using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaires.

Results and Conclusions: One patient died in the early follow-up period. Thus 16 patients were followed up with a mean of 18 months (rang 6-36). 12 (75%) patients were male and the median age was 56.5 (range 54.8 - 61.8) years. The indication to perform the operation was in 6 cases a SNAC in 5 cases a SLAC and in 3 cases a SCAC wrist. Another case was due to rheumatoid arthritis and one due to avascular necrosis of the scaphoid. 63 %of the patients had previous surgery. At last follow-up the mean pain score decreased from NRS 6.6/10 preoperatively to 2.4/10 postoperatively, the DASH score from 46 to 37 points respectively. 69% of the patients were satisfied or very satisfied. The postoperative mean range of motion (ROM) for flexion/extension was 56° (range 15-110), for pro-/supination 157° (range 115-180) and for radial-/ulnarduction 25° (range 10-40). The mean grip strength was 19kp (range 8-38), which averaged 64% of the unaffected side. All implants remained intact but there were two early dislocations with the need of revision and reposition of the implant. 3 patients developed a subsequent arthrosis with the need of revision and reposition of the implant with an average of 2.6years (range 2-3) after primary surgery. After revision two of the patients were satisfied, the third followed a total wrist fusion. There was no infection.

Patients experienced a significant reduction in pain and DASH Score. Therefore, despite a 31% revision rate, preserving wrist mobility, Amandys ® interposition arthroplasty can still be a reasonable alternative for the treatment of extensive destruction of midcarpal and radiocarpal joints.