Abstract: Objective To evaluate the clinical and kinematic results of TKAs with posterior-stabilized (PS) or cruciate-retaining (CR) prosthesis in which the JL was elevated postoperatively. Methods Patients who underwent total knee arthroplasty between January 2013 and December 2015 were collected . The patients were divided into two groups based on the prosthesis they received (PS or CR). Clinical results were evaluated by AKS knee score、AKS function score and Feller score. In vivo kinematic analysis after TKA was performed and a previously validated three-dimensional (3D) to two-dimensional (2D) image registration technique was used to obtain the kinematic data. Anteroposterior translation of the medial and lateral femoral condyles, and axial rotation relative to the tibial plateau, were analyzed. Results At time of follow-up, there were differences in the AKS knee scores、 AKS function scores 、Feller scores and postoperative ROMs between the PS and CR group. In the PS group, the magnitudes of AP translation for the medial and lateral condyle were (4.9±3.0 )mm and (12.8±3.3 )mm, respectively. Axial rotation of the tibial component relative to the femoral component was 12.9°±4.5°. In the CR group, the magnitudes of AP translation for the medial and lateral condyle were (4.3±3.5) mm and (7.9±4.2) mm respectively. Axial rotation was 6.7°±5.9°. There were statistically different between PS group and CR group in kinematics post-operatively. Conclusions Postoperative JL elevation has more adverse effects on the clinical and kinematic outcomes of CR TKAs than PS TKAs.

Key words: kinematics, total knee arthroplasty, posterior cruciate-retaining, posterior stabilized, fluoroscopic analysis