Modified Ashworth Scale

## **How to use the Modified Ashworth Scale** Physical therapists and clinicians worldwide employ the scale, and despite some critiques on its reliability, it remains a staple in assessing spasticity and treating upper limb spasticity. You can access the Modified Ashworth Scale template template from this guide. Click "Use template" to open it within the Carepatron platform, where you can customize this tool according to the information you or your institution needs. You can also click "Download" to get a free fillable PDF copy of this assessment. Here are the steps in using the scale: ### **Step 1: Prepare the environment** Before beginning the assessment, ensure access to a flat surface, preferably an examination table. The Modified Ashworth Scale requires the patient to be in a supine position, so assist them in lying face up if necessary, as this test is designed to monitor spasticity. ### **Step 2: Observe muscle tone** Once the patient is in a supine position, proceed to observe their limbs to assess muscle tone. There are two types of muscles to monitor: - **Muscles that primarily flex joints**: If you are testing a muscle that especially flexes a joint, you must place a joint in a maximally flexed position and move it to a position of maximal extension in just one second. If you need to measure the second, say "one thousand-one" out loud. Saying that should count as a second. - **Muscles that primarily extend joints**: If you are testing a muscle that primarily extends a joint, you must extend a joint in a maximally extended position and then move it to a position of maximal flexion in just one second. Make sure to count one second as you move the limb. ### **Step 3: Record observations** Take careful note of your observations as you assess each muscle. It is recommended that you assign a score immediately after examining each muscle before moving on to the next one.

## **How do you score the Modified Ashworth Scale?** Modified Ashworth Scale scores range from 0 to 4. The scoring system is as follows (Bohannon and Smith, 1987): - 0 means that there is no increase in muscle tone. - 1 means that there is a slight increase in muscle tone. This is manifested by a catch-and-release movement or minimal resistance at the end of the range of motion when the affected part(s) is moved in flexion or extension." - 1+ means a slight increase in muscle tone, manifested by a catch, followed by minimal resistance throughout the remainder (less than half) of the range of motion (ROM). - 2 means more marked increases in muscle tone through most of the range of motion (ROM), but the affected parts are easily moved. - 3 means there is a considerable increase in muscle tone; passive movement is difficult. - 4 means the affected parts are rigid in flexion or extension. The MAS is typically used to evaluate spasticity in specific muscle groups, such as the elbow flexors or wrist extensors. The examiner applies a quick, passive stretch to the joint and notes any resistance encountered. The scale can be repeated multiple times for reliability.

## **When does one typically use the Modified Ashworth Scale?** Healthcare professionals often use the Modified Ashworth Scale to monitor patients with neurological disorders as part of routine evaluations. This scale measures spasticity, a common issue in these patients. Here are the instances one can use the Modified Ashworth Scale: - **Monitoring the effectiveness of treatment plans**: The scale evaluates muscle tone to determine the efficacy of current treatment plans. By observing a patient's muscle tone during an examination, professionals can decide whether to maintain, adjust, or overhaul treatment plans based on changes in scores. - **Assessing improvement or worsening of spasticity**: Lower scores on the scale indicate improvement in spasticity, while higher scores indicate worsening spasticity. This helps track the progression of the condition over time. - **Determining treatment plan components**: The scale helps healthcare providers decide if physical therapy exercises should be included in the treatment plan. Additionally, it assists in determining the need for muscle relaxants, such as botulinum toxin injections, based on changes in scores for each muscle observed. By monitoring changes in muscle tone, healthcare providers can tailor treatment plans better to address the needs of patients with neurological disorders.

## **Benefits and limitations** The MAS provides an objective measure of muscle tone, allowing for better tracking of progress over time and comparison between different treatment methods (Harb & Kishner, 2025). It also helps identify specific muscles that may require more targeted interventions. In spinal cord injury and traumatic brain injury patients, the MAS can be used to monitor changes in muscle spasticity over time. For patients with multiple sclerosis or cerebral palsy, the MAS assesses the effectiveness of physical therapy interventions. The Modified Ashworth Scale reliability seems to vary depending on the muscle group. Generally, the elbow and wrist assessments are more reliable than those of the knee and ankle plantar muscles (Figueiredo & Zeltzer, 2011).  In addition, the scale only captures a limited range of motion and does not account for variability in different muscles within a specific muscle group. This means that both inter-rater reliability and the intra-rater reliability of the tool varies from muscle group to muscle group.

### **References** Bohannon, R. W., & Smith, M. B. (1987). Interrater reliability of a modified Ashworth scale of muscle spasticity. Physical Therapy, 67(2), 206–207. https://doi.org/10.1093/ptj/67.2.206 Figueiredo, S., Zeltzer, L., & Sitcoff, E. (2011). Modified Ashworth Scale. Stroke Engine. https://strokengine.ca/en/assessments/modified-ashworth-scale/ Harb, A., & Kishner, S. (2025, April 4). Modified Ashworth Scale. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK554572/