The Importance of the Sagittal Plane in Biomechanical Analysis of the Hip

The sagittal plane, which Pauwels regarded as being of no importance for the hip, was studied in the whole body with respect to posture while walking. After a preliminary study, which confirmed the importance of the sagittal plane for the hip, we performed a 3-dimensional modelling of the hip using the finite element method, with the aim of studying the resultant force exerted at the centre of the coxofemoral joint and of analysing the actions of the muscles from the efforts recorded. On the basis of these findings, we represented the overall mechanical problem of the hip in schematic terms as a variable dynamic balance. The results of this work also allowed us to establish in detail the impact of optimisation on the muscular actions and the impact of variations in displacement and the acceleration of the partial centre of gravity on the results recorded. Finally, the isolated hip model was developed, with the aims of allowing us to study the relations existing between variations in the angle of femoral anteversion and variations in forces, and of making a contribution to anthropological studies of the structures of locomotion through the ages.