 The research group will perform a gait analysis test on a computerized treadmill using their own non-computerized hydraulic foot, while in-socket pressures are measured. The prosthetic foot will then be replaced by a computerized prosthetic foot for one month, following which, the measurements will be repeated. Gait factors will be examined spatio-temporal data, center of pressure movement and internal loads inside the residuum will be evaluated. Comparison will also include patients satisfaction and his ability to move around, evaluated by dedicated questionnaire. 