In vitro measurements are widely used to implement gait kinematic and kinetic parameters to predict THA wear rate. Clinical tests of materials and designs are crucial to prove the accuracy and validate such measurements. This research aimed to examine the effect of CoC and CoXLPE kinematics and kinetics on wear during gait, the essential functional activity of humans, by comparing in vivo data to in vitro results. Our study hypothesis was that both implants would present the same hip joint kinematics and kinetics during gait. In total, 127 unilateral primary cementless total hip arthroplasties were included in the research. There were no statistically significant differences observed at mean peak abduction, flexion, and extension moments and THA kinematics between the two groups. THA gait kinematics and kinetics are crucial biomechanical inputs associated with implant wear. In vitro studies report less wear in CoC than CoXLPE when tested in a matched gait kinematic protocol. Our findings confirm that both implants behave identically in terms of kinematics in a clinical environment, thus strengthening CoC advantage in in vitro results. Correlated to all other significant factors that affect THA wear, it could address in a complete prism the wear on CoC and CoXLPE.
Keywords: THA kinematics; THA kinetics; ceramic on XLPE wear; ceramic on ceramic THA loading; total hip arthroplasty biomechanics.