Gitter A, Czerniecki J M, DeGroot D M
Department of Rehabilitation Medicine, Seattle VA Medical Center, University of Washington 98195.
Am J Phys Med Rehabil. 1991 Jun;70(3):142-8. doi: 10.1097/00002060-199106000-00006.
Although energy storing prosthetic feet have achieved widespread clinical acceptance, the effect of these components on the biomechanics of below-knee amputee gait is poorly understood. The purpose of this study was to determine the biomechanical adaptations used by the below-knee amputee while wearing a conventional prosthetic foot and to assess the influence of energy storing prosthetic feet on these adaptations. Mechanical power outputs of the lower extremity in five normal and five below-knee amputee subjects using the SACH, Seattle and Flex feet were studied. Ground reaction forces and kinematic data were collected at a walking speed of 1.5 m/s and were used to determine the muscular power outputs of the lower extremity during stance. Consistent patterns of muscular power output at the hip and knee of the residual limb occur. While wearing the SACH foot, negligible energy generation occurs at the prosthetic foot during pushoff. A decrease in energy absorption at the knee during the first half of stance and an increase in energy generation by the hip extensors were the major adaptations noted in the proximal muscle groups. Compared to the SACH foot, the energy storing feet demonstrated increased energy generation during pushoff. Despite the improvements in the performance of the energy storing prosthetic feet, no significant differences were found in the pattern or magnitude of knee and hip power outputs compared to the SACH foot.
尽管储能假脚已在临床上得到广泛认可，但这些部件对膝下截肢者步态生物力学的影响却知之甚少。本研究的目的是确定膝下截肢者在佩戴传统假脚时所采用的生物力学适应性，并评估储能假脚对这些适应性的影响。研究了五名正常人和五名膝下截肢者使用SACH脚、西雅图脚和Flex脚时下肢的机械功率输出。以1.5米/秒的步行速度收集地面反作用力和运动学数据，并用于确定站立期下肢的肌肉功率输出。残肢的髋部和膝部出现了一致的肌肉功率输出模式。佩戴SACH脚时，蹬离期假脚产生的能量可忽略不计。站立期前半段膝关节能量吸收减少，髋部伸肌能量产生增加，是近端肌群的主要适应性变化。与SACH脚相比，储能脚在蹬离期产生的能量增加。尽管储能假脚的性能有所改善，但与SACH脚相比，膝关节和髋关节功率输出的模式或大小没有显著差异。
