[Methods for recording and quantitative measurement of rigidity and spasticity (author's transl)].

First pathophysiological aspects of rigidity and spasticity are described with special regard to the possibilities of errors during the measurement of muscle tone in man. The following methods are explained and discussed: Psychometric techniques, physical analysis of movements (kinesiology, photobadismography, kinetometry), pendulousness tests, investigations of reflexes (T-reflex, H-reflex, H/M-ratio), electromyographic methods (after-activity, silent period, unloading-reflex, stretch-reflex, release-phaenomen), and torque measurements. In the main we discussed these techniques with the view-point of diagnosis and drug effects. Furthermore we expressed our opinion on the relevance of the different methods. Last the most important sources of errors are tabulated.