Ashworth and Modified Ashworth Scale (MAS)

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Tool Description

  • The Ashworth or Modified Ashworth Scale (MAS) is a measure of spasticity developed as a simple clinical classification to assess the anti-spastic effects of carisoprodol in multiple sclerosis. These measures have been adopted for measuring spasticity in a variety of other diagnoses, including SCI.
  • 5-point nominal scale using subjective clinical assessments of tone ranging from 0 – ‘no increases in tone’ to 4 – ‘limb rigid in flexion or extension [abduction/adduction]’. An additional grade was added (1+) for the MAS to enhance sensitivity and accommodate hemiparetic patients who typically graded at the lower end of the scale.

Availability:

Download worksheet from: http://www.rehabmeasures.org/PDF%20Library/Modified%20Ashworth%20Scale%20Instructions.pdf

or from this site: http://www.scireproject.com/sites/default/files/worksheet_ashworth.docx

ICF Domain:

Body Function – Subcategory: Neuromusculoskeletal & Movement-related Functions and Structures.

Number of Items:

Clinician/Patient may test any number of muscles affected by Spasticity.

Brief Instructions for Administration & Scoring

Administration:

  • Clinician-administered; both tests (Ashworth and MAS) are clinical examinations performed on a relaxed patient in the supine position.
  • The muscle is assessed by rating the resistance to passive range of motion (ROM) about a single joint.

Equipment: None.

Scoring:

  • It consists of a 5-point nominal scale using subjective clinical assessments of tone ranging from 0 – ‘No increases in tone’ to 4 – ‘Limb rigid in flexion or extension [abduction/adduction]’. An additional grade is added (1+) for the MAS to indicate resistance in the movement. This enhances sensitivity and accommodates hemi-paretic patients who typically graded at the lower end of the scale.

Interpretability

MCID:

Not established for SCI; but in stroke, initial change in muscle tone/spasticity in response to botox treatment was approximately a 1-point decrease on the MAS scale, reflecting a clinically significant improvement
(Shaw et al. 2010, n=333, adults with upper limb spasticity due to stroke; >1 month post-stroke)

SEM: not established
MDC: not established for the SCI population but in a stroke population, initial change in muscle tone/spasticity in response to botox treatment was an approximately 1-point decrease on the MAS scale reflecting a clinically significant improvement.

[Shaw et al. 2010, n=333, adults with upper limb spasticity due to stroke >1 month post-injury]

Typical Values: 

Score Distributions (SD):
Score 0: 25.7%
Score 1: 34.0%
Score 2: 23.7%
Score 3: 16.5%
(Sherwood et al., 2000; N=97, 95 male, 62 cervical SCI; mixed injury types; 0.5-39 years post-SCI)

Languages:

n/a

Training Required:

None specifically indicated, however the observation of resistance is subjective and requires experienced clinical judgment.

Clinical Considerations

  • This measure is commonly used in the clinical setting to assess spasticity in people with SCI. However, it should be noted that spasticity is a multi-faceted construct with individual components of spasticity weakly related to each other suggesting that different clinical scales measure unique aspects of spasticity.
  • This measure assesses single-joint resistance to passive ROM or a velocity dependent stretch reflex. They do not address spasm frequency or severity, nor do they differentiate between phasic and tonic components of spasticity. Therefore, the overall construct of spasticity is best measured with an appropriate battery of tests including the Ashworth or Modified Ashworth.
  • The Ashworth and Modified Ashworth are well-tolerated by patients.
  • This measure is easily administered during routine clinic visits and doesn’t require specialized equipment.

Measurement Property Summary

# of studies reporting psychometric properties: 15

Reliability:

  • Moderate Inter-rater Reliability (for MAS): ICC = 0.56

    (Tederko et al 2007; n=30, 23 males; mixed injury type cervical SCI; inpatient; mean time since injury = 14.1 months)

Validity:

  • Correlation of Ashworth (hip, knee, ankle) with SCATS (clonus, flexion, extension) was Moderate to High.
  • Correlation of Ashworth (hip, knee, ankle) with Penn Spasm Frequency Scale (PSFS) was Moderate.

Correlations:
Hip   knee  ankle

PSFS 0.43  0.43   0.51

Hip       -      0.90   0.67

Knee    -        -      0.77

Clonus 0.56  0.65 0.60

Flexion 0.55  0.47 0.40

Ext       0.98  0.88  0.61

(Benz et al. 2005; n=17; mixed injury types; 24-372 months post-SCI)

Responsiveness:

  • With intrathecal baclofen treatment, Ashworth scores were found to significantly decrease (P<.0001).

[Penn et al. 1989, Gianino et al. 1998, Aydin et al. 2005, Boviatsis et al. 2005]

Floor/ceiling effect:

In a group of MS or SCI patients: with intrathecal baclofen treatment, Ashworth scores were found to significantly decrease. (Boviatsis et al. 2005; n=22, 15 with MS, 7 with SCI; no SCI type data available; 12 males; mean time since injury = 2.71 years)

Reviewer

Dr. Vanessa Noonan, John Zhu, Jeremy Mak, Matthew Querée

Date Last Updated:

Nov 1, 2016

Download the measure

Download Worksheet:

Worksheet Document
Procedure:

Place the patient in a supine position.

When testing a muscle that primarily flexes a joint, place the joint in a maximally flexed position and move to a position of maximal extension over one second.

When testing a muscle that primarily extends a joint, place the joint in a maximally extended position and move to a position of maximal flexion over one second.

Video

Scoring

 

Score Modified Ashworth Scale
0 No increase in muscle tone
1 Slight increase in tone
1+ Slight increase in tone, with a catch, followed by minimal resistance
2 More marked increase in tone, but affected part(s) easily moved.
3 Considerable increase in tone and passive movement difficult.
4 Affected part(s) rigid in flexion or extension.

Equipment Needed

Ashworth:

Ashworth B. Preliminary trial of carisoprodol in multiple sclerosis. Practitioner 1964;192:540-542.
http://www.ncbi.nlm.nih.gov/pubmed/14143329

Aydin G, Tomruk S, Keles I, Demir SO, Orkun S. Transcutaneous electrical nerve stimulation versus baclofen in spasticity: clinical and electrophysiologic comparison. Am J Phys Med Rehabil 2005; 84: 584-492.
http://www.ncbi.nlm.nih.gov/pubmed/16034227

Benz EN, Hornby TG, Bode RK, Scheidt RA, Schmit BD. A physiologically based clinical measure for spastic reflexes in spinal cord injury. Arch Phys Med Rehabil 2005;86:52-59.
http://www.ncbi.nlm.nih.gov/pubmed/15640989

Bohannon RW, Smith MB. Interrater reliability of a modified Ashworth scale of muscle spasticity. Phys Ther 1987;67:206-207.
http://www.ncbi.nlm.nih.gov/pubmed/3809245

Boviatsis EJ, Kouyialis AT, Korfias S, Sakas DE. Functional outcome of intrathecal baclofen administration for severe spasticity. Clinical Neurology and Neurosurgery, 2005; 107: 289-295.
http://www.ncbi.nlm.nih.gov/pubmed/15885386

Craven BC, Morris AR. Modified Ashworth scale reliability for measurement of lower extremity spasticity among patients with SCI. Spinal Cord, 2010; doi:10.1038/sc.2009.107.
http://www.ncbi.nlm.nih.gov/pubmed/19786977

Gianino JM, York MM, Paice JA, Shott S. Quality of life: effect of reduced spasticity from intrathecal baclofen. Journal of Neuroscience Nursing, 1998; 30(1):47-54.
http://www.ncbi.nlm.nih.gov/pubmed/9604822

Haas BM, Bergstrom E, Jamous A, Bennie A. The inter rater reliability of the original and of the modified Ashworth scale for the assessment of spasticity in patients with spinal cord injury. Spinal Cord 1996;34:560-564.
http://www.ncbi.nlm.nih.gov/pubmed/8883191

Lechner HE, Frotzler A, Eser P. Relationship between self- and clinically rated spasticity in spinal cord injury. Arch Phys Med Rehabil 2006;87:15-19.
http://www.ncbi.nlm.nih.gov/pubmed/16401432

Lee KC, Carson L, Kinnin E, Patterson V. The Ashworth scale: a reliable and reproducible method of measuring spasticity. Neurorehabilitation and Neural Repair, 1989; 3:205-209.
http://nnr.sagepub.com/content/3/4/205.abstract

Mishra C, Ganesh GS. Inter-rater reliability of modified modified Ashworth scale in the assessment of plantar flexor muscle spasticity in patients with spinal cord injury. Physiother Res Int. 2014;19(4):231-7.
http://www.ncbi.nlm.nih.gov/pubmed/24619735

Noth J. Trends in the pathophysiology and pharmacotherapy of spasticity. J Neurol 1991;238:131-139.
http://www.ncbi.nlm.nih.gov/pubmed/1869888

Penn RD, Savoy SM, Corcos D, Latash M, Gottlieb G, Parke B, Kroin JS. Intrathecal baclofen for severe spinal spasticity. New England Journal of Medicine, 1989; 320(23): 1517-1521.
http://www.ncbi.nlm.nih.gov/pubmed/2657424

Priebe MM, Sherwood AM, Thornby JI, Kharas NF, Markowski J. Clinical assessment of spasticity in spinal cord injury: a multidimensional problem. Arch Phys Med Rehabil 1996; 77:713-716.
http://www.ncbi.nlm.nih.gov/pubmed/8670001

Shaw L, Rodgers H, Price C, et al. BoTULS: a multicentre randomised controlled trial to evaluate the clinical effectiveness and cost-effectiveness of treating upper limb spasticity due to stroke with botulinum toxin type A. Health Technol Assess. 2010;14(26):1-113, iii-iv.
http://www.ncbi.nlm.nih.gov/pubmed/20515600

Sherwood AM, Graves DE, Priebe MM. Altered motor control and spasticity after spinal cord injury: subjective and objective assessment. Journal of Rehabilitation Research and Development, 2000; 37 (1): 41-52.
http://www.ncbi.nlm.nih.gov/pubmed/10847571

Skold C, Harms-Ringdahl K, Hultling C, Levi R, Seiger A. Simultaneous Ashworth measurements and electromyographic recordings in tetraplegic patients. Arch Phys Med Rehabil, 1998; 79: 959-65.
http://www.ncbi.nlm.nih.gov/pubmed/9710170

Skold C. Spasticity in spinal cord injury: self- and clinically rated intrinsic fluctuations and intervention-induced changes. Arch Phys Med Rehabil 2000;81:144-149.
http://www.ncbi.nlm.nih.gov/pubmed/10668766

Smith AW, Jamshidi M, Lo SK. Clinical measurement of muscle tone using a velocity-corrected modified Ashworth scale. Am J Phys Med Rehabil, 2002; 81: 202-206.
http://www.ncbi.nlm.nih.gov/pubmed/11989517

Tederko P, Krasuski M, Czech J, Dargiel A, Garwacka-Jodzis I, Wojciechowska A. Reliability of clinical spasticity measurement in patients with cervical spinal cord injury. Ortopedia Traumatologia Rehabilitacja, 2007; 5(6): Vol 9, 467-483.
http://www.ncbi.nlm.nih.gov/pubmed/18026067