An anatomical model of the knee joint obtained by computer dissection

Abstract

This paper reports the analysis of the articular surfaces of the femur and the tibia in normal knees. Six cadaveric joints were digitized with FARO Arm electrogoniometer and elaborated off-line fitting the profiles of multiplanar sections with least square curves. We found that: the femoral medial condyle can be represented by an ellipsoid with its main axis in the AP direction, semi-axes equal to 30 and 23 ± 2 mm (roughly spherical posteriorly) and circular ML section (radius = 20 ± 2 mm); the tibial medial plateau can be approximated by a semi-cylinder with its main axis in the AP direction and circular ML section (radius = 22 ± 1.3 mm); the femoral lateral condyle can be represented by a ellipsoid with semi-axes equal to 26 and 20 ± 4 mm and an elliptic ML section with a sloped major axis parallel to the tibial spine; the articulating tibial surface in the lateral compartment is approximately flat.