Abstract
Introduction
Better functional outcomes, lower pain and better stability have been reported with knee designs which restore physiological knee kinematics. Also the ability of the TKA design to properly restore the physiological femoral rollback during knee flexion, has shown to be correlated with better restoration of the flexor/extensor mechanism, which is fundamental to the function of the human knee. The purpose of the study is to compare the kinematics of three different TKA designs, by evaluating knee motion during Activities of Daily Living. The second goal is to see if there is a correlation between the TKA kinematics and the patient reported outcomes.
Methods
Ten patients of each design, who are at least 6 months after their Total Knee Replacement, will be included in this study. Seven satisfied and 3 dissatisfied patients will be selected for each design. In this study 5 different movements will be analysed: flexion/extension; Sitting on and rising from a chair, Stair climbing, descending stairs, Flexion and extension open chain and squatting. These movements will be captured with a fluoroscope. The 2D images that are obtained, will be matched with the 3D implants. This 3D image will be processed with custom-made software to be able to analyse the movement. Tibio-femoral contact points of the medial and lateral condyles, tibio-femoral axial rotation, determination of the pivot-point will be analysed and described. After this analysis, a correlation between the kinematics and the KOOS and KSS will be investigated.
Results
(The results of the first six patients are shown, more patients are currently being tested.) The average weight-bearing ROM of the implants is 108.48° +/− 19.68°.
