The cruciate ligaments in total knee arthroplasty - A kinematic analysis of 2 total knee arthroplasties

In vivo weight-bearing fluoroscopic kinematic analysis using an interactive model fitting technique with 3-dimensional computer-aided design solid mod els was done using 16 anterior and posterior (bicruciate)-sparing and 6 pos terior cruciate-sparing total knee arthroplasties (TKAs). All patients had a satisfactory clinical result with a minimum of 12 months' follow-up. The femorotibial contact position of TKAs started posterior to the midline in e xtension. Bicruciate TKAs revealed gradual posterior femoral rollback and l imited anterior-posterior translation but remained posterior to the sagitta l plane midline in all positions. Posterior cruciate-sparing TKAs began sig nificantly posterior in extension, demonstrated progressive anterior transl ation with flexion, and had exaggerated medial condyle translation on deep knee bend. The posterior cruciate-retaining TKAs of this study had the most abnormal kinematic performance.