Palmar shelf arthroplasty, the next generation: distraction/interposition for rheumatoid arthritis of the wrist.

Rheumatoid arthritis affects approximately 1 percent of the adult population. Bilateral symmetric involvement of the wrist occurs in 85 percent of these patients, with recurrent flares and relentless progression. Anatomic changes consist of radiocarpal, intercarpal, and radioulnar subluxation and joint destruction. For advanced disease, both wrist arthrodesis and arthroplasty have been recommended. Arthrodesis has been successful for pain relief at the expense of motion. Implant arthroplasty has been unreliable, with failure rates of 25 to 50 percent at 2 to 9 years. Palmar shelf arthroplasty was introduced in 1970 as a resectional fibrous arthroplasty. The results were good but the series was small. Subsequent reports of this procedure have been inconsistent. In 1990, I initiated and have since followed a series of patients treated with the palmar shelf arthroplasty. To the basic procedure, I added joint distraction by external fixator, collagen/bone wax interposition, scapholunate stabilization, and increased immobilization time. Fourteen consecutive patients were enrolled in this study. Each carried a diagnosis of rheumatoid or psoriatic arthritis of the wrist. There were 11 women and 3 men. Age ranged from 28 to 56 years. Follow-up ranged from 2 to 7 years (average 4.2). The patients were interviewed, examined, and x-rayed. A questionnaire using an analog scale as well as the Hospital for Special Surgery scoring system was completed to assess the clinical outcome of the wrist postoperatively compared with its preoperative status and with the contralateral wrist. No patient has requested or required a revision procedure. All patients experienced improvement with both pain and function; no wrist spontaneously fused. Patient satisfaction was high. Patients with ipsilateral arthroplasty and contralateral arthrodesis preferred the arthroplasty. Hospital for Special Surgery score increased from 53 to 91 out of 100 points (p < 0.001). Range of motion averaged 50 degrees flexion, 30 degrees extension. Palmar shelf arthroplasty remains a viable option for severe rheumatoid disease of the wrist. Ideally, the procedure is performed on the dominant wrist of a patient with bilateral wrist involvement in the setting of inflammatory arthritis.