Functional performance differences between carbon fiber and fiberglass prosthetic feet

Background:Persons with lower limb amputation require increased functionality. The largest category of feet for active individuals with a transtibial amputation is energy storage and return (ESR) feet. These feet are typically constructed of carbon fiber composite materials. Recently, a prosthetic foot composed of a fiberglass composite has emerged in the market. However, there are no comparative studies of these devices.Objectives:Compare the biomechanical performance and prosthesis-related quality of life when using a fiberglass prosthetic foot design compared with traditional carbon fiber ESR designs.Study Design:This is a repeated-measures randomized cross-over trial.Methods:Gait analysis was performed on 10 experienced male subjects with unilateral transtibial amputations (K-level III) while walking on level ground and a ramp. Patient-reported outcomes were collected using the Prosthesis Evaluation Questionnaire.Results:Gait data demonstrated increased ankle dorsiflexion (P <.01), similar ankle moments (P =.07), and increased ankle power generation (P =.01) when using the fiberglass foot. The increased power generation occurred at the correct time in the gait cycle such that the timing and magnitude of peak knee flexion was unaffected (P >.19). The fiberglass foot had greater energy absorption during gait (P =.01) with no difference in energy return (P =.37). The subjects expressed improved prosthesis-related quality of life with the fiberglass foot (P =.01).Conclusions:The findings of this study demonstrate that the new ESR foot comprising a fiberglass material had better performance than traditional designs using a carbon fiber material.