Evaluation of Fixation Stability for MIS Friendly Cemented Tibial Trays Using Finite Element Method: Cement Bonding Condition, Stem Geometry and Tray Stiffness

Due to smaller incision and soft tissue sparing techniques, minimally invasive surgery (MIS) in total knee arthroplasty (TKA) has benefited many patients in terms of shortened hospital stays and quicker recoveries when compared to traditional TKA surgery [1]. A traditional TKA surgery generally requires an 8″ incision while MIS can be performed with a 3–5″ incision. To accommodate the smaller incision used in MIS TKA, MIS friendly tibial tray designs have shorter stems or use modular stem extensions as compared to traditional stemmed tibial tray designs. One of the design considerations is that the shorter stem may compromise the tibial tray’s fixation stability especially for Posterior Stabilized (PS) loading scenarios in which the tibial tray may be subjected to large anterior/posterior (A/P) load through the engagement of the tibial insert and the femoral component and cause tipping of the tray.