Abstract
To investigate spasticity and associated reaction in patients with cerebrovascular diseases (CVD), we reported on the two following points: 1) neurophysiological factors of spasticity and 2) characteristics of the spinal neural function in the affected arm during voluntary movement of the leg with the H-reflex in research on associated reaction in patients with CVD. 1) Spasticity was characterized by an increase in of spinal reflex. Factors increasing spinal reflex were separated into the increasing of excitatory fibers from the central nervous system (CNS), afferent sensory fibers, efferent motor fiber and muscle function, and the decreasing of inhibitory fibers from CNS, presynaptic inhibition, and function of renshaw cell. 2) H-reflex, one of evaluations of the spasticity, was recorded from the affected abductor pollicis brevis in relaxation (rest 1), straight leg raising (SLR) task for 15 sec. (task 1), relaxation (rest 2) and SLR task for 15 sec. (task 2) in 3 patients (cases 1-3) with CVD. Muscle tonus of the affected arm was moderate-severe (Case 1), moderately (Case 2) and slightly (Case 3) hypertonus. The amplitude ratio of H/M in the affected arm was analyzed before and during the task. In case 1, the amplitude ratio of H/M in tasks 1 and 2 was significantly higher than that in rest 1. The amplitude ratio of H/M during task 2 was significantly higher than that in task1. In case 2, the amplitude ratio of H/M in tasks 1 and 2 was significantly higher than that in rest 1. No significant difference between the task 1 and 2 was noticed in the amplitude ratio of H/M. In case 3, no significant difference in all conditions was noticed in the amplitude ratio of H/M. It is suggested that a good relationship between spinal neural function of the affected arm during voluntary movement of the leg and the muscle tonus of the affected arm was seen in patients with CVD.
