Joint proprioception before and after total knee arthroplasty.

To investigate the effects of total knee arthroplasty on joint proprioception, the absolute angular error of the knee in 38 consecutive patients before and after total knee arthroplasty for osteoarthritis and in 23 age-matched control subjects were examined. Varus and valgus laxity of the knee and muscle strengths of the thigh were measured using appropriate instruments. There were no significant differences in absolute angular error before and after total knee arthroplasty, independent of retaining or substituting the posterior cruciate ligament. The absolute angular error of the knee with a normal appearing anterior cruciate ligament was larger than that with a missing anterior cruciate ligament before total knee arthroplasty and decreased significantly after surgery. The absolute angular error correlated with the varus and valgus laxity of the knee, but did not correlate with the strength of thigh muscles after total knee arthroplasty. These results suggest that deficiency of the anterior cruciate ligament may not adversely affect proprioception in severe knee osteoarthritis. In addition, proper ligament balance may partly contribute to better proprioception after total knee arthroplasty.