[Surgical therapy of chronic polyarthritis of the hand]

Surgical therapy and the common surgical procedures for the rheumatoid hand are presented: synovectomy, boutonnière deformity, swan-neck deformity, arthroplasty, and surgical therapy of the rheumatoid thumb. The indications, early and late results, and the prophylactic value of synovectomy are discussed and compared with synoviorthesis (intra-articular injection of radioisotopic beta-emitters) in early stages of synovitis. In general, radioisotope synovectomy has reduced the need for early operative synovectomy. If synoviorthesis has no significant effect or if biomechanical factors are predominant in the affected joint (tenosynovitis, massive distension of the capsule and extensor mechanism or large masses of fibrin), then operative synovectomy is indicated. Multicenter studies have confirmed that pain can be relieved and joint swelling reduced by synovectomy for over 10 years after the operation. However, no significant preventive or retarding effects could be proven with regard to the progression of deformity or further radiologic changes. The risks in tenosynovectomy are minimal and the prognosis for improved function and prevention of ruptures is excellent. Restorative procedures on tendons are discussed in conjunction with restoration of joint function. Pathogenetic mechanisms of boutonnière and swan-neck deformities and their therapeutical consequences (soft tissue procedures and arthroplasty of the respective joints) are discussed. Because of the unpredictability of joint resection arthroplasty, many attempts have been made to develop joint prostheses. Surgical experience with cemented components, constrained hinges and prostheses with a fixed axis has been disappointing and forbids their routine clinical use. The most widely used device is the silastic spacer developed by Swanson, a silicone rubber implant acting as flexible hinge to maintain the joint relationship and improve resection arthroplasty. Several authors have obtained good long-term results using the Swanson silastic prosthesis for MP and interphalangeal arthroplasty. However, the silastic spacer still leaves room for improvement, which is particularly evident in patients with constitutional or drug-induced (steroid hormones) ligamentous laxity where bone resorption can be seen due to the piston effect and abrasion of the silicone as well as to sinking and often breakage of the prosthesis. Attempts to prevent this effect are reported. To obtain good functional results with MP arthroplasty, adequate function of the interphalangeal joints and thumb is essential.(ABSTRACT TRUNCATED AT 400 WORDS)