Severe Bilateral Fixed Flexion Deformity—Simultaneous or Staged Total Knee Arthroplasty?

Outcomes of 29 simultaneous (SimBTKA) and 38 staged bilateral total knee arthroplasty (StaBTKA) subjects with severe (≥16°) bilateral fixed flexion deformity (FFD) were retrospectively investigated. SimBTKA patients were significantly younger (63 ± 8 vs 68 ± 7, P > .01). At 2 years, SimBTKA subjects had significantly better residual FFD (2.5° ± 5.1° vs 5.4° ± 6.6°, P = .02) and Knee Society function score (75.7 ± 25.7 vs 69.3 ± 24.1, P= .02). However, Knee Society knee scores, Oxford Knee Scores, and Short Form-36 scores were similar. These suggest no large clinical advantage of SimBTKA over StaBTKA. We feel that severe bilateral FFD is not an absolute indication for SimBTKA.