The MAS is a simple, yet effective, 6-point scale ranging from 0 to 4, with an additional grade of 1+. Each grade corresponds to a specific level of spasticity:
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 (ROM) 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, making passive movement difficult. 4: Affected part(s) rigid in flexion or extension.
