Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, RN115, Boston, MA 02215, USA; Department of Orthopedic Surgery, Harvard Medical School, Boston, MA, USA.
Department of Engineering Science and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
J Biomech. 2014 Mar 21;47(5):1104-9. doi: 10.1016/j.jbiomech.2013.12.024. Epub 2014 Jan 10.
Limited plantar flexor strength and hip extension range of motion (ROM) in older adults are believed to underlie common age-related differences in gait. However, no studies of age-related differences in gait have quantified the percentage of strength and ROM used during gait. We examined peak hip angles, hip torques and plantar flexor torques, and corresponding estimates of functional capacity utilized (FCU), which we define as the percentage of available strength or joint ROM used, in 10 young and 10 older healthy adults walking under self-selected and controlled (slow and fast) conditions. Older adults walked with about 30% smaller hip extension angle, 28% larger hip flexion angle, 34% more hip extensor torque in the slow condition, and 12% less plantar flexor torque in the fast condition than young adults. Older adults had higher FCU than young adults for hip flexion angle (47% vs. 34%) and hip extensor torque (48% vs. 27%). FCUs for plantar flexor torque (both age groups) and hip extension angle (older adults in all conditions; young adults in self-selected gait) were not significantly <100%, and were higher than for other measures examined. Older adults lacked sufficient hip extension ROM to walk with a hip extension angle as large as that of young adults. Similarly, in the fast gait condition older adults lacked the strength to match the plantar flexor torque produced by young adults. This supports the hypothesis that hip extension ROM and plantar flexor strength are limiting factors in gait and contribute to age-related differences in gait.
老年人跖屈肌力量和髋关节伸展幅度（ROM）有限，据信这是导致常见的与年龄相关的步态差异的原因。然而，目前还没有研究量化与年龄相关的步态差异中力量和 ROM 的使用百分比。我们检查了 10 名年轻和 10 名健康老年人在自主选择和控制（慢和快）条件下行走时的峰值髋关节角度、髋关节扭矩和跖屈肌扭矩，以及相应的功能能力利用率（FCU）估计值。我们将 FCU 定义为可用力量或关节 ROM 的百分比，用于行走。与年轻人相比，老年人在慢走条件下髋关节伸展角度小 30%，髋关节屈曲角度大 28%，髋关节伸肌扭矩大 34%，快走条件下跖屈肌扭矩小 12%。与年轻人相比，老年人在髋关节屈曲角度（47%比 34%）和髋关节伸肌扭矩（48%比 27%）方面具有更高的 FCU。跖屈肌扭矩（两个年龄组）和髋关节伸展角度（所有条件下的老年人；自主选择步态的年轻人）的 FCU 均未显著<100%，且高于其他检查的指标。老年人髋关节伸展 ROM 不足，无法像年轻人那样以大的髋关节伸展角度行走。同样，在快速步态条件下，老年人缺乏与年轻人产生的跖屈肌扭矩相匹配的力量。这支持了髋关节伸展 ROM 和跖屈肌力量是步态限制因素并导致与年龄相关的步态差异的假设。
