An instrument for the bedside quantification of spasticity: a pilot study

Spasticity is a velocity-dependent phenomenon; the quicker the limb is moved the more resistance is encountered. A compact, portable instrument was constructed for recording the angle at the knee, the rate of change of angle (angular velocity) and the force encountered at the ankle when the limb was flexed. A pilot study was performed on 5 normal volunteers and 5 patients with spasticity. A preliminary index of spasticity was extracted from the measurements, being 0.163±0.059 N.s/deg (mean±SD) for the patients and 0.052±0.030 N.s/deg for the normal group