Assessment of the effects of carbon fiber and bionic foot during overground and treadmill walking in transtibial amputees

- We investigated the effect of a bionic foot in ten transtibial amputees.
- Motor abilities and the energy cost of walking in different conditions were tested.
- The differences with the dynamic carbon fiber foot were analysed.
- The bionic foot allowed for a lower energy cost of walking, particularly on floor.

ObjectiveTo determine the energy cost of walking (ECW) of a bionic foot (Proprio-Foot®) during ambulation on floor and on treadmill (at different slopes) compared to walking with a dynamic carbon fiber foot (DCF). We evaluated transtibial amputees (TTAs) perceived mobility with the prosthesis and their walking ability on stairs and ramps.MethodTTAs were enrolled. The ECW tests were conducted on a regular floor surface and on treadmill with −5%, 0% and 12% slopes. In all conditions, TTAs were asked to walk at their own self-selected speed. Metabolic and cardiac data were collected using a portable gas analyzer. Tests were performed at six data collection points: first with a standard suction system (SSS) and the DCF; second, with the DCF after 7 weeks of using a hypobaric suspension system (HSS) with the DCF; third, after 1 h of Proprio-Foot® use together with the HSS; three more testing sessions were carried out at 30-day intervals, i.e., after 30, 60 and 90 days of Proprio-Foot® use together with the HSS. TTAs perceived mobility using the prosthesis and walking ability on stairs and ramps were assessed.ResultsTen TTAs completed the measurements. ECW with the Proprio-Foot® obtained in the final floor-walking test was significantly lower than ECW with the DCF (p = 0.002). No significant improvements were observed for perceived mobility or walking ability.ConclusionsResults suggest that use of the Proprio-Foot® can lower the ECW for TTAs in spite of its added weight compared to DCF.