Knee arthrodesis following total knee arthroplasty in rheumatoid arthritis.

Twenty-seven knees in 23 patients, all with seropositive rheumatoid arthritis and failed total knee arthroplasty, were treated by arthrodesis. Twenty of the 27 knees were solidly fused. A fusion aligned in 7 degrees +/- 5 degrees of valgus and knee flexion from zero to 30 degrees was associated with the highest rate of arthrodesis, the lowest rate of progression of disease in other joints, and the highest functional scores. Stable fixation using either internal or external fixation gave the most predictable rate of arthrodesis. Persistent sepsis and bone stock losses were associated with failure of arthrodesis, even under the best circumstances. All of the 20 successfully arthrodesed knees were completely functional.