Twenty-eight patients with end-stage knee osteoarthritis were randomized to receive a medial ball-and-socket TKA (n=14) or a posterior-stabilized TKA (n=14); outcomes were compared with 14 healthy controls. The primary outcome of interest was knee gait biomechanics across the gait cycle using statistical parametric mapping (SPM). Secondary outcomes included temporospatial gait parameters and KOOS subscales. Outcomes were assessed pre-operatively and at 12±1 months post-operatively. Overall, the results showed that, relative to controls, the MBS group demonstrated fewer sagittal-plane knee angle deviations (i.e., a gait pattern closer to controls) than the posterior stabilized (PS) group, which retained reduced knee flexion in both stance and swing; both TKA groups improved across all KOOS domains without between-implant differences. These findings suggest MBS may better restore physiologic sagittal kinematics by 12 months, while symptomatic and functional gains (PROMs) are comparable between designs.