Abnormal Volitional Hip Torque Phasing and Hip Impairments in Gait Post Stroke

作者:Hyngstrom Allison*; Onushko Tanya; Chua Matthew; Schmit Brian D
来源:Journal of Neurophysiology, 2010, 103(3): 1557-1568.
DOI:10.1152/jn.00528.2009

摘要

Hyngstrom A, Onushko T, Chua M, Schimt BD. Abnormal volitional hip torque phasing and hip impairments in gait post stroke. J Neurophysiol 103: 1557-1568, 2010. First published January 20, 2010; doi: 10.1152/jn.00528.2009. The purpose of this study was to quantify how volitional control of hip torque relates to walking function poststroke. Volitional phasing of hip flexion and extension torques was assessed using a load-cell-instrumented servomotor drive system in 11 chronic stroke subjects and 5 age-matched controls. Hips were oscillated from similar to 40 degrees of hip flexion to 10 of hip extension at a frequency of 0.50 Hz during three movement conditions [hips in phase (IP), 180 degrees out of phase (OP), and unilateral hip movement (UN)] while the knees and ankles were held stationary. The magnitude and phasing of hip, knee, and ankle torques were measured during each movement condition. Surface electromyography was measured throughout the legs. Over ground gait analysis was done for all stroke subjects. During robotic-assisted movement conditions, the paretic limb produced peak hip torques when agonist hip musculature was stretched instead of midway through the movement as seen in the nonparetic and control limbs (P < 0.012). However, mean torque magnitudes of the paretic and nonparetic limbs were not significantly different. Abnormalities of paretic hip torque phasing were more pronounced during bilateral movement conditions and were associated with quadriceps overactivity. The magnitude of flexion torque produced during maximal hip extension was correlated with the Fugl Meyer Score, self-selected walking speed, and maximal hip extension during over ground walking. These results suggest that hyperexcitable stretch reflexes in the paretic limb impair coordinated hip torque phasing and likely interfere with walking function post stroke.

  • 出版日期2010-3