Wrist Replacement or Fusion?

Imagine trying to wash dishes, get dressed, or use the toilet with only one hand. That’s what happens to people with a painful arthritic wrist. For many people, arthritis of the wrist can cause pain, loss of function, and extreme disability.

If you have painful, disabling wrist arthritis, which is better for you: wrist fusion or replacement? In this article, hand surgeons from the Warren Alpert Medical School (Brown University, Rhode Island) help answer that question by reviewing what we know about total wrist arthroplasty. A historical summary with brief description of each of the four generations of implants is included. Problems with each generation of prostheses and resulting design changes are discussed. Outcomes are compared with wrist fusion or arthrodesis, the alternative to wrist replacement.

Arthrodesis can get rid of pain and restore strength in badly degenerated wrist joints. Fusion surgeries make the wrist strong again, but they greatly reduce the wrist’s range of motion. This makes fusion surgery a poor choice for some people.

Today, the wrist joint can be replaced with an artificial joint (also called a prosthesis). Total wrist arthroplasty (another word for replacement) can also relieve the pain caused by wrist arthritis.

When severe arthritis has destroyed the wrist joint, an artificial joint gives the joint a new surface, which lets it move smoothly without causing pain. Increased strength and improved motion makes it possible to once again perform daily activities of living with greater ease and ability.

Total wrist arthroplasty (TWA) has been around for over 100 years but the procedure is still done much less often than other joints in the body, such as the knee or the hip. Over the last 40 years, the implants (prostheses) have been changed and improved through four generations of products. The result is a prosthetic that is longer lasting with fewer surgical and postoperative complications.

Today’s fourth generation implant has a porous surface to allow bone to grow in and around it. This is different from previous implants that always required cement to hold them in place. Cementless implants mean less bone destruction and improved durability of the implant. The newer systems are made of cobalt chrome, titanium, and polyethylene (plastic). Two titanium screws are used to help stabilize the implant.

The authors provide photos of the three current fourth-generation total wrist implant systems available on the market. They reviewed considerations and techniques for surgeons, and included photos taken during open surgical procedures. They also provided X-rays showing implant alignment as soon as the prosthesis was in place.

Surgeons must choose patients carefully for this procedure to ensure success. A low-activity lifestyle is important. Patients must agree to activity restrictions such as no heavy lifting, avoiding over extending the wrist, and no participation in vigorous sports activities. Younger, more active patients may be advised to have an arthrodesis (fusion) rather than a wrist replacement to reduce pain and disability associated with wrist arthritis.

There are other factors that might prevent a patient from being a good candidate for wrist replacement. The most common one is poor bone stock. Poor bone stock refers to brittle bones (osteoporosis), bone infection, and bone erosion or deformity. The need for crutches or cane to walk and/or the inability to stand up without using the arms to push off would also keep a patient from having a wrist replacement. Anyone who is not a good candidate for wrist replacement can still consider wrist fusion as a possible treatment solution to their painful symptoms.

The number of studies comparing results between wrist fusion and replacement are limited. Until recently (third-generation wrist arthroplasty), the complication rate was still much higher for arthroplasty (21 per cent) than for fusion (13 per cent). Long-term studies of fourth-generation implants are not available yet. Early reports (after three to five years) show improvement in pain with good satisfaction rates (95 per cent or more of the patients were happy with results).

In summary, anyone interested in the evolution of wrist arthroplasty (replacement) will find this article of interest. Complications such as infection, soft tissue imbalance, and implant loosening and dislocation are much improved with the new fourth-generation prostheses. There are still times when wrist fusion is considered a better treatment option but this determination is made on a case-by-case basis. And the authors say that all things being con