Migration of CS vs CR Insert in TKA Using RSA

In the researchers' words

Background: The choice whether or not to preserve the posterior cruciate ligament (PCL) in total knee arthroplasty (TKA) is coupled to the us of a PCL-retaining (CR) or a condylar (CS) insert. The CS insert is anterior-lipped (AL) to prevent anterior translation of the femur on the tibia with flexion and compensate the function of the PCL. Currently both the CR and CS insert are made of highly cross-linked polyethylene (HXPLE) to theoretically reduce wear related osteolysis. However, this also might diminish the fracture toughness and crack propagation of the insert. The investigators expect that due to the high contact forces on the anterior lip of the CS insert during flexion, especially in younger and more active patients, and the lower fracture toughness of HXPLE, the CS insert insert might show more migration, wear or other damage compared to the CR insert in the long-term, which might lead to more revisions in the CS insert compared to the CR insert. To measure the migration and wear, during surgery tantalum markers will be inserted in the host bone using a marker inserter. The displacement of the prosthesis with reference to the host bone will be measured using model-based RSA. Both tantalum markers ande the inserter are already used for study purposes. However, the safety and usability are not registered before. Objective: The primary objective is to compare the…