A review of evidence on mechanical properties of running specific prostheses and their relationship with running performance.

The review included only English-language peer-reviewed articles, so relevant conference papers and theses were excluded. Six studies came from the same research group and sometimes used the same data set, which limits how independent the evidence is. Testing methods varied widely, including loading rate, peak load, mounting, friction, and environmental conditions, so stiffness values are not directly comparable. Only 10 of 20 studies reported numerical stiffness values, and others reported graphs or functions instead. Hysteresis was reported in only three studies, and there is no standard way to report it. All included studies were focused on adults, so the findings do not apply to pediatric running prostheses. Manufacturers do not report standardized technical specifications, so objective comparison is difficult. A study changed stiffness and shape together, so the separate contribution of stiffness cannot be isolated.

The authors declared that no financial support was received for the research, authorship, or publication.

Do not read this review as showing that a stiffer running prosthesis improves speed or energy cost. The studies used different tests, several used the same data, and a study changed stiffness and shape together, so the effect of stiffness alone cannot be separated.