Importance of TKA size selection for fine tuning the laxity in the knee

Evaluation of TKA by means of robotic cadaver studies and associated numerical analyses allows quantifying the effect of component size selection on the resulting laxities of the knee throughout its arc of flexion (envelope of motion). Relatively small changes of 2mm in tibial insert height and/or femoral AP dimensions were shown to have a large impact on the envelope of motion and might be an indicator for how the knee feels to a patient. Finer size increments in the portfolio of a TKA system allow a refined adjustment of the knee laxities and could facilitate a more natural feeling of the knee.