Beyond Ashworth. Electrophysiologic quantification of spasticity.

Spasticity is a hallmark of upper motor neuron lesion, which is easily identified but is difficult to quantify and treat. The Ashworth scale lacks reliability. Available biomechanical and electrophysiologic studies offer a more reliable measure of spastic hypertonia but have limited clinical utility. A uniformly acceptable, reliable, and practical measure of spasticity continues to elude the clinician. This chapter reviews the basic neuroanatomy and physiology of the stretch reflex and the pathophysiology of the spasticity. Current biomechanical and electrophysiological techniques are used to quantify spasticity.