modified ashworth scale modified ashworth scale the modified ashworth scale (mas) measures resistance during passive soft-tissue stretching and is used as a simple measure of spasticity. scoring (taken from bohannon and smith, 1987): 0: no increase in muscle tone 1: slight increase in muscle tone, manifested by a catch and release or by minimal resistance at the end of the range of motion when the affected part(s) is moved in flexion or extension 1+: slight increase in muscle tone, manifested by a catch, followed by minimal resistance throughout the remainder (less than half) of the rom 2: more marked increase in muscle tone through most of the rom, but affected part(s) easily moved 3: considerable increase in muscle tone, passive movement difficult 4: affected part(s) rigid in flexion or extension modified ashworth scalepurposemeasure of spasticity