Rationale: Pain at the anterior side of the knee after total knee arthroplasty is still a common phenomenon with an incidence reported to be as high as 49 percent. The aetiology is poorly understood and several mechanisms have been postulated. Next to the influence of alignment on retinacular stresses, overstuffing of the patellofemoral joint and instability also lead to higher retinacular stresses and are shown to lead to anterior knee pain. These mechanisms are all related to surgical technique and implant positioning. There are also mechanisms related to prosthesis design, like the sagittal curve, trochlear depth and trochlea shape.~New implant designs like the Journey II prothesis are designed to replicate optimal geometry and optimal tibiofemoral and patellofemoral kinematics. Therefore, the Journey II Bi-Cruciate Stabilized (BCS) seems the optimal implant to reduce anterior knee pain. However, large registry studies show that a higher revision rate is seen when no patellar button is used in case of the Journey II BCS. The use of a patellar button is still under debate, but using an onlay patella button has clear influence on the patella tracking. Therefore, there might be a relation between the use of an onlay patella button and the retinacular balance and thus clinical results.~With current surgical instrumentation the positioning of the prosthesis based on the kinematics of the natural knee is challenging, and a small error can completely counteract the normal motion defined by the implant design/geometry. Therefore, comparative studies are only leading to new evidence when the surgical technique is including objective and accurate tools, like the CORI robotic platform. With the CORI, component positioning can be set based on constitutional alignment and ligament functioning. Furthermore, the patellofemoral compartment can be taken into account during the surgery to enable optimal geometry replication of the trochlea in the sagittal plane. This enables the surgeon to position the components accurately within the envelop of motion of a specific joint.~With new emerging imaging techniques, the investigators are able to investigate in vivo patella tracking. One of these promising techniques is the 4D CT imaging. This technique is proven to be accurate within 1 mm and 1° and therefore useful to investigate the patellofemoral compartment.~The current proposal aims to investigate the patellar tracking in patients receiving Journey II BCS total knee arthroplasty (TKA) before and one year after surgery, positioned with the CORI Robotics System instrumentation. The hypothesis is that less change in patella tracking before and after surgery will lead to less anterior knee pain complaints. Patella tracking is investigated using 4Dimensional Computer Tomography (4D CT) imaging.~Research participants/locations:~A total of 100 participants will be included in the study from two sites in the Netherlands (Radboudumc and Treant medical centers). Half of the participants will undergo TKA placed with the CORI Robotics and a patella onlay button and the other half (50 participants) will undergo a TKA placed with the CORI Robotics System and without a patella onlay button.
The current proposal aims to investigate the patellar tracking in adult patients receiving Journey II Bi-Cruciate Stabilized (BCS) total knee arthroplasty (TKA) before and one year after surgery, positioned with the CORI Robotics System instrumentation. The hypothesis is that less change in patella tracking before and after surgery will lead to less anterior knee pain complaints. Patella tracking is investigated using 4Dimensional Computer Tomography (4D CT) imaging.~Researchers will compare the group of participants that will receive a patella onlay button with the group that will not receive a patella onlay button with their TKA to see if there is a difference in motion and pain experienced by the participants.