Modified Ashworth Scale
Also written as: MAS — Modified Ashworth Scale
A six-point ordinal scale used in rehabilitation to grade the degree of muscle spasticity or resistance to passive stretch in a limb segment.
Full Definition
The Modified Ashworth Scale (MAS) is a widely used clinical tool in PM&R for quantifying muscle tone abnormalities, particularly spasticity and rigidity, by rating resistance encountered during passive range-of-motion testing. The scale ranges from 0 (no increase in tone) to 4 (affected part rigid in flexion or extension), with an intermediate score of 1+ (slight increase with a catch and release). It was adapted from the original Ashworth Scale by Bohannon and Smith in 1987 to improve sensitivity at the lower end. Editors must capitalise both 'Modified' and 'Ashworth' as part of the named scale, and should use 'MAS' as the standard abbreviation following first use. The MAS is distinct from the Tardieu Scale, which also assesses spasticity but incorporates velocity-dependent stretch responses.
Usage
Usage note: Capitalise all words when citing the full scale name. The abbreviation 'MAS' must be defined at first use. Note that 'MAS' is also used for 'motor assessment scale' in some contexts; specify if ambiguity is possible.
In Context
- "The physiatrist recorded a Modified Ashworth Scale score of 2 in the right elbow flexors prior to botulinum toxin injection." — Physiatric procedure note
- "Post-intervention, MAS scores improved from 3 to 1+ across all measured muscle groups." — Clinical research outcomes report