Kuhnen Henry R, Rybar Megan M, Onushko Tanya, Doyel Ryan E, Hunter Sandra K, Schmit Brian D, Hyngstrom Allison S
Department of Biomedical Engineering, Marquette University, Milwaukee, Wisconsin, USA.
Muscle Nerve. 2015 Mar;51(3):446-8. doi: 10.1002/mus.24520.
Stroke-related changes in maximal dynamic hip flexor muscle fatigability may be more relevant functionally than isometric hip flexor fatigability.
Ten chronic stroke survivors performed 5 sets of 30 hip flexion maximal dynamic voluntary contractions (MDVC). A maximal isometric voluntary contraction (MIVC) was performed before and after completion of the dynamic contractions. Both the paretic and nonparetic legs were tested.
Reduction in hip flexion MDVC torque in the paretic leg (44.7%) was larger than the nonparetic leg (31.7%). The paretic leg had a larger reduction in rectus femoris EMG (28.9%) between the first and last set of MDVCs than the nonparetic leg (7.4%). Reduction in paretic leg MDVC torque was correlated with self-selected walking speed (r2=0.43), while reduction in MIVC torque was not (r2=0.11).
Reductions in maximal dynamic torque of paretic hip flexors may be a better predictor of walking function than reductions in maximal isometric contractions.
与中风相关的最大动态髋屈肌疲劳性变化在功能上可能比等长髋屈肌疲劳性更具相关性。
10名慢性中风幸存者进行了5组，每组30次的髋部屈曲最大动态自主收缩（MDVC）。在动态收缩完成前后进行了最大等长自主收缩（MIVC）。对患侧腿和非患侧腿均进行了测试。
患侧腿髋部屈曲MDVC扭矩的降低（44.7%）大于非患侧腿（31.7%）。在MDVC的第一组和最后一组之间，患侧腿股直肌肌电图的降低幅度（28.9%）大于非患侧腿（7.4%）。患侧腿MDVC扭矩的降低与自我选择的步行速度相关（r2=0.43），而MIVC扭矩的降低则不相关（r2=0.11）。
患侧髋屈肌最大动态扭矩的降低可能比最大等长收缩的降低更能预测步行功能。
