Introduction Biomechanics plays a crucial function in osteoarthritis. Changes in the biomechanical parameters of the contralateral knee following total knee arthroplasty (TKA) may result in pain in the contralateral knee. The objective of this study was to examine preoperative and postoperative gait measurements on the contralateral leg following a TKA for a variety of gait measures at a self-selected normal gait pace in a similar speed population. Method There were 11 patients included in the study, and their average age was 68 (7 females and 4 males). Gait analysis was performed at a sampling frequency of 120 Hz using nine cameras Qualisys motion capture systems (Qualisys AB, Sweden). To process the kinematic data, Visual 3D C-Motion Software was used. Results Ankle plantar flexion (0.01), knee abduction during the terminal stance (0.002), and knee adduction during the initial swing (0.01) all showed a significant difference. In spatiotemporal data, walking speed (0.01), stance time (0.01), step length (0.005), and stride length (0.001) all showed significant differences. There were significant differences in knee flexion-extension (0.04) values. Conclusion A change in the contralateral knee's biomechanics as a result of TKA is strongly suggested by significant alterations in the knee's stance phase, joint angle, and MAP. The research may help to modify the stride of the contralateral leg to decrease the advancement of osteoarthritis.