The variable-axis knee prosthesis. Two-year follow-up study.

This study reports the clinical results following knee replacement with the variable-axis knee prosthesis. All patients have been followed for a minimum of two years. The first consecutive fifty-two patients, comprising a total of fifty-five knee replacements, were personally reviewed by an independent evaluator. The results on a subjective basis consisted of 79 per cent good to excellent results, 15 per cent fair results, and 6 per cent failures. Failures were related to infection or continued pain. Fair results reflected some patellar discomfort or instability. There was no detectable clinical loosening of the components in any patient. To date, the design of the variable-axis prosthesis appears to offer promise in the control of the complication of prosthetic loosening.