Pinzur M S, Wolf B, Havey R M
Gait Analysis Laboratory, Loyola University Medical Center, Maywood, Illinois 60153, USA.
Foot Ankle Int. 1997 Oct;18(10):635-8. doi: 10.1177/107110079701801006.
Measurements of the vertical component of ground reaction force (ORF) and dynamic center of pressure (COP) were recorded for five subjects with midfoot level amputations and six with Syme's ankle disarticulation amputations. All of the subjects underwent amputation surgery as a consequence of peripheral vascular disease and diabetes. GRF measurement was accomplished with the F-Scan system (Tekscan, Boston, MA). Each group exhibited a consistent, reproducible pattern of gait. Subjects with Syme's ankle disarticulation initiated initial loading response, i.e., heel strike, with a concentration of GRF in the center of the anatomic heel. COP progressed along the midline to the center of the anatomic forefoot, where GRF was concentrated at push-off. Midfoot amputees initiated loading at the lateral-posterior heel. COP progressed medially to the midline, where it progressed distally to the level of the distal residual limb (proximal metatarsal metaphyses). It then shifted medially under the base of the first metatarsal, where a small concentration of GRF occurred at push-off, similar to the normal foot. These findings explain the decreased magnitude of propulsion seen in midfoot level amputees and may explain the seemingly paradoxical increased metabolic cost of walking observed in midfoot amputees as compared with Syme's ankle disarticulation amputees.
记录了5名中足平面截肢患者和6名Syme's踝关节离断截肢患者的地面反作用力（ORF）垂直分量和动态压力中心（COP）的测量值。所有受试者均因外周血管疾病和糖尿病接受了截肢手术。使用F-Scan系统（Tekscan，马萨诸塞州波士顿）完成地面反作用力测量。每组均表现出一致、可重复的步态模式。Syme's踝关节离断的受试者开始初始加载反应，即足跟触地时，地面反作用力集中在解剖学足跟中心。压力中心沿中线向前足解剖学中心移动，在此处地面反作用力集中在蹬离期。中足截肢者在足跟后外侧开始加载。压力中心向内侧移动至中线，然后向远侧移动至残余肢体远端（近端跖骨干骺端）水平。然后它在第一跖骨底部内侧移动，在蹬离期地面反作用力在此处有一小部分集中，类似于正常足。这些发现解释了中足平面截肢者推进力大小降低的原因，也可能解释了与Syme's踝关节离断截肢者相比，中足截肢者步行时代谢成本看似矛盾增加的现象。
