Shape Analysis of the Femoral Head: A Comparative Study Between Spherical, (Super)Ellipsoidal, and (Super)Ovoidal Shapes.

In this work, MacConaill's classification that the articular surface of the femoral head is better represented by ovoidal shapes rather than purely spherical shapes is computationally tested. To test MacConaill's classification, a surface fitting framework was developed to fit spheres, ellipsoids, superellipsoids, ovoids, and superovoids to computed tomography (CT) data of the femoral proximal epiphysis. The framework includes several image processing and computational geometry techniques, such as active contour segmentation and mesh smoothing, where implicit surface fitting is performed with genetic algorithms.

Sensitivity of the results produced by the inverse dynamic analysis of a human stride to perturbed input data.

The results of the inverse dynamic procedures used in gait analysis are known to be highly dependent on the quality of the kinematic and dynamic input data and on the biomechanical model anatomical data. In this paper the sensitivities of the system response to imprecision in the input data and biomechanical model were calculated. It was shown that the gait analysis results were very sensitive to the identification of the point of application of the external forces.