Medial pivot kinematics describes the normal axial rotation of the lateral compartment of the knee about the inherently more constrained medial compartment that occurs during flexion and extension. Medial stabilized total knee arthroplasty designs replicate the asymmetric medial-lateral constraint profile of the native knee and can closely recreate normal knee kinematics in vivo. The highly conforming medial articulation provides sagittal stability that substitutes for the posterior cruciate ligament without a cam-post mechanism and serves as a pivot point about which the lateral compartment rotates during flexion and extension. Impressive clinical results and excellent long-term survivorship offer a compelling argument for the use of medial stabilized implants during primary total knee arthroplasty.
Houston Methodist Orthopedics & Sports Medicine, Outpatient Center, Houston Methodist Hospital, Houston, TX
S.J.I.: Royalties: Innomed, Zimmer, Kyocera, Biomet, Smith and Nephew, Microport; Paid Consultant: IMDS, Zimmer, Kyocera, Biomet, Smith and Nephew, Microport, Osteoremedies; Stock/stock options: Nimbic Systems; Orthopedic publications, editorial/governing boards: J Arthroplasty, Board member (editorial board: The Knee, International Editorial Board). C.D.C. declares that there is nothing to disclose.
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