TOTAL VERSUS MIDCARPAL WRIST FUSION: A PROSPECTIVE COMPARATIVE STUDY

Abstract

Aim: Total Wrist fusion is the main procedure for treatment of postraumatic and degenerative wrist osteoarthritis. During the last decade, midcarpal fusion has become more and more popular as it preserves motion. The purpose of this study was to compare the functional and workers compensation results of both treatments on active workers.

Material and Methods: A prospective study to evaluate 77 patients (76 male and 1 female) who underwent wrist fusion, between 2002 to 2006, with an average of 28 months of follow-up (range, 12–58 months) were made. The mean age were 32 years (range, 25–48 years) and all patients were medium or high level workers with postraumatic and degenerative wrist osteoarthritis. The aethiology in 67% of the patients was SNAC wrist. Right hand was involved in 65% of the patients.

Thirty-eight patients were treated with scaphoid excision and 4-corner fusion using dorsal circular plate. Thirty-nine patients were treated with total wrist fusion using one single, dorsal, precontoured and tapered plate for osteosynthesis and third carpometacarpal joint (CMCJ-3) was included. All patients were immobilised in a cast for 4 weeks after surgery.

Postoperative complications, pain (visual analogue scale), clinical and functional outcome based on Green and O’Brien score, grip strength, X-ray evaluation, time to return to work and activity level were evaluated and compared.

Results: Consolidation was obtained in all cases at 10 weeks. Pain evaluation score was 19,2 (4-corner) and 13,8 (total fusion) on post-op time. The mean modified Mayo wrist score was 70,4 (4-corner) and 69 (total wrist). Average lost of pinch strength was 43% (4corner) and 21% (total fusion). 2 patients with 4-corner fusion required total wrist arthrodesis. Three cases who had a total wrist fusion, required implant removal.

The average time to return to work was 17 weeks (4-corner) and 16,2 weeks (total fusion). All patients return to work. Twelve percent of four-corner fusion and 72% of total wrist fusion return to the same work level with restrictions (until 33% of activity). Twenty-two percent of 4-corner fusion and 28% of total wrist fusion were unable to return to their previous activity level, performing lower intensity work activities. Overall satisfaction was high in both groups with 85% (4corner) and 93% (total fusion).

Conclusion: Both fusion techniques allows an effective stabilization, maintaining the bone stock and eliminate wrist pain with fast return to work.

Total wrist fusion had less surgical failures, better level of satisfaction, lesser lost of force than 4-corner fusion, with less potential for further deterioration with time. However, 4-corner fusion allows return to work with a similar activity level and preserve a functional range of motion in patients with high levels of activity.