| The gait of an individual with transtibial amputation requires more energy cost, has higher relative exercise intensity, and is asymmetrical, compared to individuals with nonpathological gait. The energy storing-releasing prosthetic feet, the C-Walk and the FF, are speculated to provide better push-off and thus, improve gait performance compared to the traditional SACH prosthetic foot. However, no research has been done to substantiate this conjecture. The purpose of this study was to investigate foottype differences of the C-Walk, the FF, and the SACH in individuals with transtibial amputation, based on physiological (energy cost, relative exercise intensity, gait efficiency, physiological cost index, and rating perceived exertion), functional (self-selected walking velocity, quality of life, and daily physical activity), and temporal/distance (stride length, cadence, gait symmetry) assessments. Eight male subjects with transtibial amputation were recruited. A two-factor (speed and type of prosthesis) repeated measures design involving multiple speed treadmill walking (53.64, 67.05, 80.46, 93.87, 107.28 m/min, and the self-selected walking velocity) was employed. A Medgraphics Cardio2 metabolic cart and an ECG radiotelemetry system were used for oxygen uptake and heart rate measurement, respectively. An instrumented Gateway(TM) treadmill system was used for the treadmill walking tests and for collecting temporal/distance measurement. Relative exercise intensity was expressed as a percentage of age predicted maximum heart rate (%APMHR). The physiological cost index was calculated as [(heart rate during walking-resting heart rate)/speed]. Two questionnaires, the SF-36 and the Prosthesis Evaluation Questionnaire, were employed to evaluate quality of life. A pedometer was used to investigate physical daily activity. Our results revealed that the C-Walk had a trend of improved gait performance compared to the SACH; however, most of the foottype differences were not statistically significant. In general, the FF demonstrated greater improvement than the SACH and significant foottype differences were seen in several physiological and functional measurements. The results suggested that the FF may be more beneficial to physically active individuals with transtibial amputation, compared to the C-Walk and the SACH. |
