A research team studied the influence of prosthesis interfaces on gait and on the perception of pain, comfort, and the overall interface/prosthesis system in people with transtibial amputations. When correlating the subjects’ perception with the interface properties, the researchers concluded that the mechanical properties are the most influential, and that silicone elastomer showed appropriate characteristics for lower levels of activity for which it is recommended.
Commercial samples of three interface materials were selected: block copolymer, silicone gel  and silicone elastomer. Using standardized prostheses, four subjects performed gait tests at three imposed cadences in a barometric platform. The subjects also filled in a questionnaire about their perception.
Silicone gel presented the highest asymmetries of vertical ground reaction forces and was perceived as the most painful and uncomfortable. Silicone elastomer led to the most symmetric load distribution between legs and was perceived as the most comfortable. Block copolymer showed better overall biomechanical behavior and better subject perception.
The results indicated that prescription of silicone gel should be rethought, as it is only adequate for specific and occasional situations, and block copolymer should be considered adequate for active and less active amputees, according to the study’s authors.
The research, A study on the influence of prosthetic interface material in transtibial amputees’ gait, was published in Bio-Medical Materials and Engineering.
