The Modified Ashworth Scale (MAS) better measures muscle hypertonia instead of spasticity.
Ashworth Scale for grading Spasticity
1) no increase in muscle tone;
2) slight increase giving a catch when part is moved in flexion or extension;
3) more marked increase in tone but only after part is easily flexed;
4) considerable increase in tone; and
5) passive movement is difficult and affected part is rigid in flexion or extension.
The Ashworth scale is one of the most widely used methods of measuring spasticity, due in a large part to the simplicity and reproducible method.
The MAS better measures muscle hypertonia instead of spasticity.
Modified Ashworth Scale for Grading hypertonia
The Tardieu Scale differentiates contracture from spasticity whereas the MAS is confounded by it.
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
What is spasticity?
•Diagnostic definition: ‘a motor disorder characterised by a velocity dependent increase in tonic stretch reflexes that results from abnormal intra-spinal processing of primary afferent input’ (Young 1994)
• Functional definition: the abnormal motor control caused by an UMN lesion (as in spastic paraparesis)
Common Causes of spasticity:
Brain damage caused by lack of oxygen, as can occur in near drowning or near suffocation