Aetna considers total wrist arthroplasty medically necessary for rheumatoid arthritis affecting the wrist in persons who have radiographic evidence of wrist joint destruction with demonstrated resistance or failure to conservative medical treatment (3 or more months of non-steroidal antiinflammatory drugs (NSAIDS), disease modifying anti-rheumatic drugs (DMARDs), and/or glucocorticoids, as appropriate).

Aetna considers total wrist arthroplasty experimental and investigational for diagnoses other than rheumatoid arthritis because there is inadequate evidence in the peer-reviewed published clinical literature regarding its effectiveness.

Total wrist arthroplasty (TWA) involves the implantation of a prosthetic joint, with the goals of reducing pain and preserving or increasing wrist mobility.  The procedure is almost always performed to relieve the symptoms of severe arthritis.  These components come in extra-small, small, medium, and large sizes to match patient anatomy.  To enable movement and prevent dislocation, the polyethylene spacer has a convex end that slides on the surface of a concave plate on the radial component. 

Several wrist implants have been developed since the early 1970s.  First-generation were silicone implants, such as those designed by Swanson in the 1980s.  Second-generation implants typically included 2 metal components that articulated by means of a ball-and-socket or a hemispheric design.  Many of these early implants were taken off the market because of problems with joint imbalance and dislocation.  The third generation of wrist prostheses were developed in an effort to better approximate the center of motion to prevent imbalance and dislocation.  Examples include the revised Meuli design (MWP III), as well as the Trispherical, the Universal, and the Biaxial designs, the latter of which has been discontinued.

Wollstein and Carlson (2013) stated that the most common forms of salvage surgery for wrist arthritis of any stage are four corner fusion and proximal row carpectomy.  Younger, high demand patients with early arthritis may not be candidates for this type of salvage surgery.  These investigators described a technique and preliminary case series of a minimal radio-carpal arthroplasty aimed at patients with initial and isolated wrist arthritis (stage 1).  This procedure does not preclude any procedure that may become necessary in the future.  A series of 19 male heavy laborers with scapho-lunate advanced collapse (SLAC grade 1 to 2) wrist osteoarthritis that felt the wrist arthritis was prohibiting their function enough to warrant surgery, but were unwilling to undergo a salvage procedure, were treated with the technique.  The average age was 57.2 (± 7.7) years.  The average follow-up period was 40.3 months (9 to 63 months).  All patients returned to heavy labor.  No revision surgery was needed within the follow-up period.  Range of motion (ROM) and grip strength did not significantly improve.  Patient satisfaction was high despite imperfect results.  The authors concluded that minimal arthroplasty as described may provide a temporary solution for active patients with symptomatic early wrist arthritis who are not candidates for salvage wrist surgery.  Moreover, they stated that longer-term follow-up as well as investigation of additional stabilization procedures is needed.

Boeckstyns et al (2013) noted that severely destroyed post-traumatic wrists are usually treated by partial or total wrist fusion or proximal row carpectomy.  The indications for and longevity of TWA are still unclear.  These researchers analyzed a series in which one last-generation TWA was used as a salvage procedure for wrists with severe arthritis due to traumatic causes.  The data were prospectively recorded in a web-based registry.  A total of 7 centers participated; 35 cases had a minimum follow-up time of 2 years.  Average follow-up was 39 (24 to 96) months.  Pain had improved significantly at follow-up, mobility remained unchanged.  The total revision rate was 3.7 %, and the implant survival was 92 % at 4 to 8 years.  Very few studies have described specific results after TWA in post-traumatic cases and almost none using classical "third-generation" implants.  The number of cases and the follow-up in the published series were small.  The authors concluded that although painful post-traumatic wrists with severe joint destruction can be salvaged by partial or total fusion; evaluated at short- to midterm, TWA can be an alternative procedure and gave results that were comparable to those obtained in rheumatoid cases.

Yeoh and Tourret (2014) reviewed the evidence on total wrist replacement from the last 5 years; 8 articles met a minimum set standard.  The results of 405 prostheses were available, including 7 different manufacturers.  The mean follow-up was 2.3 to 7.3 years with an average age of 52 to 63 years.  Rheumatoid arthritis was the indication in 42 % of patients.  Motec demonstrated the best post-operative DASH scores.  Only Maestro achieved a defined functional ROM post-operatively.  Universal 2 displayed the highest survival rates (100 % at 3 to 5 years), while Elos had the lowest (57 % at 5 years).  Bi-axial had the highest complication rates (68.7 %), while Remotion had the lowest (11 %).  Wrist arthroplasty preserves some ROM; functional scores improved and were maintained over the mid- to long-term.  Complication rates were higher than wrist fusion, with reports of radiological loosening and osteolysis.  The authors stated that the evidence does not support the widespread use of arthroplasty over arthrodesis, and careful patient selection is essential.