Center of Excellence for Limb Loss Prevention and Prosthetic Engineering, Veterans Affairs Puget Sound Health Care System, 1660 S. Columbian Way, Seattle, WA, USA.
Gait Posture. 2011 Jan;33(1):41-7. doi: 10.1016/j.gaitpost.2010.09.021. Epub 2010 Oct 25.
The biomechanics of amputee turning gait has been minimally studied, in spite of its integral relationship with the more complex gait required for household or community ambulation. This study compares the biomechanics of unilateral transtibial amputees and non-amputees completing a common turning task. Full body gait analysis was completed for subjects walking at comparable self-selected speeds around a 1m radius circular path. Peak internal and external rotation moments of the hip, knee and ankle, mediolateral ground reaction impulse (ML GRI), peak effective limb length, and stride length were compared across conditions (non-amputee, amputee prosthetic limb, amputee sound limb). Amputees showed decreased internal rotation moments at the prosthetic limb hip and knee compared to non-amputees, perhaps as a protective mechanism to minimize stress on the residual limb. There was also an increase in amputee sound limb hip external rotation moment in early stance compared to non-amputees, which may be a compensation for the decrease in prosthetic limb internal rotation moment during late stance of the prior step. ML GRI was decreased for the amputee inside limb compared to non-amputee, possibly to minimize the body's acceleration in the direction of the turn. Amputees also exhibited a shorter inside limb stride length compared to non-amputees. Both decreased ML GRI and stride length indicate a COM that is more centered over the base of support, which may minimize the risk of falling. Finally, a longer effective limb length was found for the amputee inside limb turning, possibly due to excessive trunk shift.
尽管与家庭或社区活动所需的更复杂步态密切相关，但对截肢者转弯步态的生物力学研究甚少。本研究比较了单侧小腿截肢者和非截肢者在完成常见转弯任务时的生物力学情况。在以相似的自我选择速度围绕 1 米半径圆形路径行走时，对受试者进行了全身步态分析。在非截肢者、假肢和健肢的情况下，比较了髋关节、膝关节和踝关节的最大内旋和外旋力矩、内外侧地面反作用力冲量（ML GRI）、最大有效肢体长度和步长。与非截肢者相比，假肢髋关节和膝关节的内旋力矩减小，这可能是一种保护机制，以最小化残肢的应力。与非截肢者相比，在假肢的前一步的后期站立时，假肢健肢髋关节的外旋力矩也增加，这可能是对假肢内旋力矩减小的补偿。与非截肢者相比，截肢者的内侧肢体的 ML GRI 减小，这可能是为了最小化身体在转弯方向上的加速度。截肢者的内侧肢体的步长也比非截肢者短。较小的 ML GRI 和步长表明质心更靠近支撑基础，这可能会最小化跌倒的风险。最后，发现截肢者的内侧肢体转弯时的有效肢体长度较长，这可能是由于躯干过度移位。
