The dynamic quantitation of spasticity with automated integrals of passive motion resistance

A method is described for quantitating spasticity in the forearm or lower leg. The limb is carried through passive linear motion at varying angular velocities. At high velocities forceful spasms develop opposing the direction of rotation. The degree of muscular reaction is plotted as torques with characteristic amplitudes and time durations, and the torque magnitude integrated into a meaningful work measurement. Spasticity is defined as the work output in response to angular velOcity input per 100 degree cycle (back and forth) of passive motion. A spasticity index obtained from the total work value at varying velocities may be used as a measure of drug response, and is reportable in fundamental physical units. A wide range of antispastic agents has been tested and many have proved effective for short periods when administered intravenously. Diazepam, given orally in one case, effectively reduced spasticity for 5 weeks.