The purpose of a recent biomechanical experiment series of 24 cadaver tests was to clarify injury mechanisms and tolerance limits of the lower legs, especially of the foot, ankle joint and tibia. Using a pneumatic coaxial-impactor, fresh, uninjured Post Mortem Human Subjects (PMHS) were exposed to an impact against the plantar foot surface. The experimental set-up was designed to simulate a floorboard-foot impact, which occurs when the moving (intruding) footwell of a car hits the foot, and vice versa in a frontal collision. The independent variable was the velocity of the impacting mass. Each foot has been used for a separate experiment. Extent and pattern of post-impact injuries were detected by evaluation of x-rays and subsequent dissection of the knee and ankle joint. The same test set-up was used for two subsequent series of a total of 60 dummy tests, using a Hybrid III dummy. In the first series (20 tests) the dummy was equipped with instrumented legs, in the second series (40 tests) with an advanced lower leg. The results of this study contribute to: (1) injury mechanisms and tolerance limits as a function of the test variables; (2) a correlation of PMHS and dummy test results; (3) a discussion of injury and performance criteria; and (4) to a discussion of measurements on dummy lower legs as predictors for lower leg injuries. (A)
Abstract