Biomechanical methods of analysis of mechanisms of restoration of walk of patients in the late recovery period of a stroke

In the recovery period of a stroke, the patient acquires such kind of walking stereotype, which is related to the work of the stored motion units. The body mobilizes the remaining opportunities, minimizes energy costs and changes the natural algorithms of movements, when the patient tries to restore the motion activity. The simplification of walking algorithms is mainly due to the fact that a variety of movements and the number of muscles involved in walking are minimized. So, the normal stereotype of walking, associated with the work of the ankle, the knee and the hip joints, is replaced by a pathological one, which is characterized mainly by the work of the hip joint. The work of the hip joint changes from rotation around the axis, perpendicular to the sagittal plane, to rotation around the axis, which is directed at an angle to the axial plane. We assume that this is due to the inclusion of the torso muscles in the process of walking, which is associated with large amplitudes of the displacement of its centre of masses. This stereotype of walking, in our opinion, can be described with the help of the theorem on the change in the angular momentum of the system with respect to the vertical axis of rotation. Consideration of biomechanical principles that affect the development of the pathological stereotype of walking will allow understanding how one can influence the faster recovery of the correct stereotype, and also choose individual methods of physical rehabilitation and orthosis that allow bringing the pathological stereotype to the norm.