Many studies have been carried out to analyze the behaviour of the femur under walking loads and quite good estimations of the density distribution have been obtained by application of a bone remodelling algorithm [Bisatkos, 2005] (among others). However, obvious difficulties have forced these models to make important assumptions about geometry and loads. Regarding geometry, a standard model is usually employed to overcome this difficulty [Sommer, 1982]. Secondly, the loads applied to the model are usually taken from the literature [Brand, 1986]. Thirdly, the kind of analysis. Because of the complexity of bone remodelling models, static analysis of gait have been usually done to estimate local stresses in the femur, needed for the bone remodelling algorithm. Finally, the validation of results was only qualitative. In this work all these limitations have been overcome. As far as the authors know, this is the first study to analyze the mechanical behaviour of a human femur considering the gait dynamics and taking all the data from the same subject (geometry, load data, bone density obtained through CT scanning). The goal of the work has been to adjust the parameters of the bone remodelling model to this specific femur.