An Anatomically Based 3-D Coordinate System for the Knee Joint

In the study of joint kinematics, it is necessary to establish a consistent and repeatable coordinate system to compare results among different specimens and studies, especially since kinematic data are sensitive to the variations in the choice of the coordinate systems (Blankevoort et al., 1988). For the knee joint, several coordinate systems have been described (Grood and Suntay, 1983; van Kampen and Huiskes, 1990; Veress et al., 1979). Some investigators have used a coordinate system fixed to the testing device or the measuring device, requiring an accurate and repeatable alignment of the knee in the device (e.g., van Kampen and Huiskes, 1990). Others have used coordinate systems based on the approximate anatomy of the knee without providing a detailed description of the derivation of the coordinate system (Koh et al., 1992; Veress et al., 1979). Therefore, the objective of this study is to use the precise quantitative anatomy of the knee to define a knee coordinate system that is repeatable across different specimens.