Immediate effects of unaffected arm exercise in poststroke patients with spastic upper limb hemiparesis

摘要

Background: Spasticity is a major disabling symptom in stroke patients. Clinically, one of the goals of management of stroke patients should be to reduce spasticity. Recent evidence suggests that motor recovery after stroke comprises a hierarchical, dynamic framework of interacting mechanisms in brain cortex. We hypothesized that unaffected arm exercise can stimulate the ipsilateral motor cortex and change the affected upper limb function and spasticity in stroke patients. To test the hypothesis, we evaluated the effects of unaffected arm exercise on spasticity of the affected upper limb and motor function in stroke patients. Methods: The study was performed in 41 chronic stroke patients with upper limb hemiparesis. Affected upper limb spasticity and function were assessed at baseline and after each intervention by the modified Ashworth Scale and Fugl-Meyer Assessment, respectively. Patients were also evaluated clinically by the modified Rankin Scale, Functional Independence Measurement and National Institutes of Health Stroke Scale. Subjects stood for 10 min during the control period, and then cycled an arm crank ergometer at 50% of maximum work load for 10 min by the unaffected arm in standing position. Results: The mean age at study entry was 64.6 ± 1.7 years. The latency between onset of stroke and the study was 109.0 ± 17.0 months (range, 6-495). The cause of hemiparesis was cerebral infarction (n = 21), intracerebral hemorrhage (n = 17) or subarachnoid hemorrhage (n = 3). Exercise significantly improved the modified Ashworth Scale compared with baseline (p < 0.0001). No such change was noted after the control intervention. The Fugl-Meyer Assessment score did not change after exercise compared with baseline (p = 0.95). Conclusions: We conclude that 10 min of unaffected arm exercise improves the affected upper limb spasticity in stroke patients. Further studies are needed to determine the exact mechanism of such improvement and the long-term effects of unaffected arm exercise on motor performance.