TIBIO-POPLITEUS IMPINGEMENT AFTER TKA: TIBIAL COMPONENTS SHOULD BE EITHER MORE ANATOMIC OR UNDERSIZED

Goals of the study(1) to investigate the relationships between the bony contours of the knee and the Popliteus Tendon (PT) in the healthy knee and after implantation of a TKA and (2) to analyze the influence of implant sizing.HypothesisWith an apparently well-sized TKA, the position of the PT during knee flexion is modified compared with the preoperative situation.MethodIn 4 fresh frozen cadavers we injected the PT with Barium-Sulfate and a CT-scan was performed from 0° to 140°. We implanted copies of TKAs’ obtained from the manufacturer, made with a non radio-opaque polymer (Acrylonitrile butadiene styrene) with additive manufacturing technology. Each cadaver received either a normosized (cortical fit), oversized (3mm overhang), undersized (3mm under-coverage) or mobile bearing (normosized) prosthesis. The limb was CT-scanned again. 3D-reconstructions were created using Mimics software (Fig 1). The pre-post operative position of the PT was analyzed with Matlab software. We quantified the postoperative po...