Title

Stroke-related Changes in Neuromuscular Fatigue of the Hip Flexors and Functional Implications

Document Type

Article

Publication Date

1-2012

Source Publication

American Journal of Physical Medicine & Rehabilitation

Source ISSN

0894-9115

Abstract

Objective: The aim of this study was to compare stroke-related changes in hip flexor neuromuscular fatigue of the paretic leg during a sustained isometric submaximal contraction with those of the nonparetic leg and controls and to correlate fatigue with clinical measures of function.

Design: Hip torques were measured during a fatiguing hip flexion contraction at 20% of the hip flexion maximal voluntary contraction in the paretic and nonparetic legs of 13 people with chronic stroke and 10 age-matched controls. In addition, the participants with stroke performed a fatiguing contraction of the paretic leg at the absolute torque equivalent to 20% maximal voluntary contraction of the nonparetic leg and were tested for self-selected walking speed (10-m Walk Test) and balance (Berg).

Results: When matching the nonparetic target torque, the paretic hip flexors had a shorter time to task failure compared with the nonparetic leg and controls (P < 0.05). The time to failure of the paretic leg was inversely correlated with the reduction of hip flexion maximal voluntary contraction torque. Self-selected walking speed was correlated with declines in torque and steadiness. Berg-Balance scores were inversely correlated with the force fluctuation amplitude.

Conclusions: Fatigue and precision of contraction are correlated with walking function and balance after stroke.

Comments

American Journal of Physical Medicine & Rehabilitation, Vol.91, No. 1, (January 2012): 33–42. DOI.