The study has investigated some load aspects of the gait of elderly, vascular, lower limb amputees in early stage of rehabilitation, in day to day realistic conditions. The aims were: 1) to understand the gait of recent vascular amputees better, 2) to quantify mechanical loads with two different assistive walking devices. To reach these targets: a removable novel pylon transducer was designed; a fully portable data acquisition system and instrumented canes were used. The new pylon transducer comprised two main parts so that the prosthesis did not need to be altered: 1) an valuminium. bell)) placed within the prosthetic shank tube, having a flange at its base on which the tube of the prosthesis comes to bear; 2) the body of the transducer located inside the bell with an upper contact flange and having clearance to allow the bonding of strain gauges in four levels. A full calibration of the six channels followed by static and dynamic validation tests has been undertaken. They showed a mean accuracy of 7% with a sufficient linearity to be confident in the provided results. Data were recorded through an eight channels 12-bit data acquisition system. At a sampling frequency of 6411z, the recording duration was I hour. Two series of patients have been included in the sample: 30 transtibial and 10 transfemoral amputees. A new pattern for the vertical ground reaction force is described: the second peak was absent, evidently transmitted by the load on the walking devices. The mean load on the walking devices was 35 percent of the body weight. It was also shown that the walking devices not only transmitted axial load but also assisted in the forward acceleration of the body. Three typical gait patterns have been found in the temporal parameters of the gait but none could be discerned for the load distribution.

Following lower-limb amputation, patients suffer from sensory loss within the prosthesis/residuum complex leading to diminished proprioception and balance. Artificial sensory systems have the potential to improve rehabilitation outcomes including better functional usage of lower-limb prostheses to achieve a higher quality of life for the prosthetic users. The purpose of this work was to develop and test the e fficacy of a vibrotactile feedback system for lower-limb amputees that may augment feedback during complex balance and movement tasks. Responses to different vibrotactile stimuli frequencies, locations, and physical conditions were assessed. Key outcome measures for this work were the response time and response accuracy of the subjects to the different stimulator configurations. Frequencies closer to 250 Hz applied to the anterior portion of the thigh resulted in the quickest reaction times. When multitasking, reaction times increased. These preliminary results indicate that vibrotactile sensory feedback may be viable to use by lower-limb amputees.

Following lower-limb amputation, patients suffer from sensory loss within the prosthesis/residuum complex leading to diminished proprioception and balance. Artificial sensory systems have the potential to improve rehabilitation outcomes including better functional usage of lower-limb prostheses to achieve a higher quality of life for the prosthetic users. The purpose of this work was to develop and test the e fficacy of a vibrotactile feedback system for lower-limb amputees that may augment feedback during complex balance and movement tasks. Responses to different vibrotactile stimuli frequencies, locations, and physical conditions were assessed. Key outcome measures for this work were the response time and response accuracy of the subjects to the different stimulator configurations. Frequencies closer to 250 Hz applied to the anterior portion of the thigh resulted in the quickest reaction times. When multitasking, reaction times increased. These preliminary results indicate that vibrotactile sensory feedback may be viable to use by lower-limb amputees.