A new biomechanical method for objective measurement of spasticity: A preliminary study

Abstract

The assessment of the various impairments in brain damage including spasticity is important. The purpose of this study was to develop a new biomechanical method based on quantification of velocity reduction (VR) suitable for clinical use. A highly reliable system was developed to apply a constant torque perturbation at the elbow. This system was used to measure the VR in 30 healthy adults and 10 hemiplegic patients. In healthy subjects, the mean VR was 3.02 (SE (standard error) = 0.29). In hemiplegic patients, the mean VR in the impaired arm (81.47, SE= 2.87) was significantly higher than the VR () either in the nonimpaired arm (9.86, SE= 0.92) (WSRT (Wilcoxon Signed Ranks Test): Z = -12.74; p<0.001), or the normal (3.02) p<0.001). The interaction between the associated reaction (AR) and the asymmetrical tonic neck reflex (ATNR) with head away from the impaired arm made a significant higher VR (90.41, SE=3.43) (p<0.001). The correlation between the VR () and the Modified Ashworth Scale scores was significant (Spearman�s rho = 0.77, p<0.001). It is concluded that the quantification of velocity reduction may be used as an objective method of measuring spasticity in neurological conditions. © MA Healthcare Limited 2014