Muscle and reflex changes with varying joint angle in hemiparetic stroke

Abstract

In spastic ankle muscles, the abnormalities in intrinsic and reflex components of joint torque varied systematically with changing position over the full angular range of motion, indicating that clinical perceptions of increased tone may have quite different origins depending upon the angle where the tests are initiated.Furthermore, reflex stiffness was considerably larger in the non-paretic limb of stroke patients than in healthy control subjects, suggesting that the non-paretic limb may not be a suitable control for studying neuromuscular properties of the ankle joint. Our findings will help elucidate the origins of the neuromuscular abnormalities associated with stroke-induced spasticity.