Gait and Functional Outcomes Between Cruciate-Retaining and Cruciate-Substituting Implants in Total Knee Arthroplasty: A Prospective, Randomized Study.

Significant debate persists about posterior cruciate-retaining (CR) versus posterior cruciate-substituting (PS) implant design for total knee arthroplasty (TKA). This study sought to test the hypothesis that CR TKA will facilitate improved early functional outcomes in gait compared with PS TKA. Patients were randomized to either the CR or PS implant. Various patient-reported and surgeon-reported outcomes as well as gait analyses were obtained pre- and postoperatively. Patients undergoing PS TKA had higher University of California, Los Angeles activity scores at 12 months. No significant difference in spatiotemporal, kinematic, or kinetic parameters between groups was detected, but there was a trend toward quadriceps overuse gait pattern in the CR group. Patients undergoing TKA with a PS implant were more willing to engage in regular higher level physical activity. The CR implant may be a risk factor for quadriceps overuse gait pattern, while the PS implant may be protective against quadriceps overuse. (Journal of Surgical Orthopaedic Advances 28(3):215-223, 2019).