Relative decreases in knee extension torque with increased knee extension velocities in stroke patients with hemiparesis.

I examined the isokinetic knee extension torque (KET) produced by the paretic and nonparetic lower limbs of 27 stroke patients, with hemiparesis, at knee extension velocities (KEVs) of 30 degrees, 60 degrees, 120 degrees, and 180 degrees/sec. The purpose of this study was to determine whether the relative decreases in KET at velocities greater than 30 degrees/sec were different on the two sides. To further investigate this relative decrease, the relationship between the torque at 30 degrees/sec and those at higher speeds also was examined on each side. Relative decreases in KET differed between speeds, but not between sides. Torques at speeds greater than 30 degrees/sec were correlated significantly with the torque at 30 degrees/sec. These findings suggest that patients with hemiparesis and minimal muscle spasticity may have difficulty moving forcefully at higher speeds because they are weak. Therapeutic interventions, therefore, might be most beneficial when they are directed toward helping patients with hemiparesis activate their weak muscles.