Measures of Gait Efficiency of Three Multi-Axial, Vertical Shock and Energy Storing-Return Prosthetic Feet During Simple & Complex Mobility Activities

Specific Aims * Compare the effectiveness of popular prostheses for improving performance in physically demanding tasks and environments. * Compare amputee performance to a group of high-functioning non-amputees to determine performance differences between the groups. Hypotheses: Prosthetic feet with shock absorbing and torsional features will perform better in field activities. Prosthetic feet with high energy return and low mass will perform better during treadmill running. Non-amputee controls will demonstrate superior performance in all outcomes in both field and laboratory environments compared to amputee subjects. Relevance: This study has the potential to quantify differences between highly mobile amputees and non-amputees. Additionally, it will provide objective measures of how different prostheses may enhance mobility of soldiers with amputations. The study will compare laboratory and field measures to indicate which conditions increase efficiency of prostheses during rapidly changing mobility demands. This has the potential to permit retention of already trained soldiers.