Acta Scientific Orthopaedics (ISSN: 2581-8635)

Research Article Volume 5 Issue 11

Geometric Modeling of the Knee Articular Surface with Neutral Boundary Alignment

Lorenzo Deveza1* and Ilwhan Park2*

1Baylor College of Medicine, Houston, TX, USA
2Lento Medical Inc., Houston, TX, USA

*Corresponding Author: Lorenzo Deveza, Baylor College of Medicine, Houston, TX, USA.

Received: September 05, 2022; Published: October 11, 2022


Knee mechanics is reliant on surface geometry and ligament attachments. Herein, we propose an elliptical cam model representing the femoral articular surface to explain the contact characteristics between the tibiofemoral and the patellofemoral articulations. This occurs in conjunction with a smooth transition of MCL and LCL tension to patella tendon tension that enables knee flexion without a loss of stability. The model is developed based on the Neutral Boundary Alignment (NBA) approach and has the following implications: 1) the asymmetry of distal femoral and tibial condyles is closely linked to the position of the epicondyles; 2) the epicondyles play important roles in femoral rotation in concert with MCL and LCL; 3) these features adjust the elliptical cam model to establish the concurrent motion between the tibiofemoral and patellofemoral motion with respect to the center of ellipse that would help dictate unique knee motion. In the foregoing analysis, we evaluate MRI knee images to illustrate various measures of knee asymmetry between individuals. As will be demonstrated, the asymmetry between the condyles varies and is not related to varus/valgus angle. This may have implications for total knee replacement planning and future implant design.

Keywords: Knee Alignment; Neutral Boundary Alignment; Kinematic Axis Alignment; Knee Surgery; Total Knee Replacement; Knee Biomechanics


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Citation: Lorenzo Deveza and Ilwhan Park. “Geometric Modeling of the Knee Articular Surface with Neutral Boundary Alignment". Acta Scientific Orthopaedics 5.11 (2022): 71-78.


Copyright: © 2022 Lorenzo Deveza and Ilwhan Park. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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