In this study, alignments, that is, settings of neutral angle and neutral position, of hip joint of hip disarticulation prosthesis (HDP) are examined by using numerical simulation. A numerical simulator based on neuro-musculo-skeletal human with HDP walking model is used as numerical evaluation tool of HDP. Walking was generated by the simulator in the cases of that the position of the rotation center of the hip joint was changed back and forth. Results show that, in the case that the position was set forward position, stability is higher, but the gait is asymmetry. In the case that the position was set backward position (set nearer from anatomical hip joint), stability is lower, but the gait is more symmetry than the former.
