A Comparative Study of Conventional and Energy-Storing Prosthetic Feet in High-Functioning Transfemoral Amputees

Graham LE, Datta D, Heller B, Howitt J. A comparative study of conventional and energy-storing prosthetic feet in high-functioning transfemoral amputees.ObjectiveTo compare the results of gait analysis, timed walking tests, and socket comfort for transfemoral amputees wearing initially a Multiflex conventional prosthetic foot and then a Vari-Flex energy-storing prosthetic foot.DesignExperimental crossover trial.SettingA regional prosthetic and amputee rehabilitation tertiary referral center in a teaching hospital.ParticipantsSix established unilateral transfemoral prosthetic users.InterventionsNot applicable.Main Outcome MeasuresGait analysis, a timed walking test, and a Prosthetic Socket Fit Comfort Score for each amputee wearing the Multiflex foot and then repeated wearing the Vari-Flex foot.ResultsWearing the Vari-Flex foot, our subjects walked faster in the gait lab (1.38±0.13m/s, P<.001) and took more equal step lengths at fast speed (1.063±0.05, P<.05). They also had greater peak ankle dorsiflexion at push-off on the prosthetic side (18.3°±4.73°, P<.001) and 3 times as much power from the prosthetic ankle at push-off (1.13±0.22W/kg, P<.001). There were no significant changes in temporal symmetry or loading of the prosthetic limb, in the timed walking test with each foot, or in the comfort score.ConclusionsA transfemoral amputee who wears an energy-storing foot can have a more symmetric gait with regard to some measures of spatial symmetry, kinetics, and kinematics than one who wears a conventional foot. However, in this study important aspects such as more symmetric loading and comfort did not differ significantly between the 2 foot types.