Upper motor neuron lesions: their effect on muscle performance and appearance in stroke patients with minor motor impairment

Abstract

Objective: To evaluate muscular performance and appearance in patients with prior stroke who were ambulatory.

Design: Nonrandomized study.

Setting: University hospital laboratory.

Subjects: Sixteen persons (11 men, 5 women) with minor motor impairments, 6 to 24 months after stroke, were included. As reference, data were used from a population-based sample of 144 men and women.

Main outcome measurements: Muscle performance was evaluated using a Kin-Com dynamometer in both the affected and the nonaffected leg. Peak isometric strength was measured at a 60 degree angle in both extension and flexion. Maximal isokinetic strength was measured at 60 degrees/sec and at 180 degrees/sec. Endurance was evaluated during isometric and dynamic knee extensions. Muscle biopsies were taken on nine patients and muscle tissue areas were determined with computed tomography.

Results: The affected leg was weaker but not different in relative endurance compared with the nonaffected side. The performance of the nonaffected side was somewhat lower than that of a matched reference population. No major difference in fiber composition between the affected and nonaffected legs was noted, except for a lower degree of capillarization in the affected leg.

Conclusion: In well-functioning stroke patients with good motor performance, further muscle training that includes resistance exercise might be indicated.