How Is Spasticity Measured? The Modified Ashworth Scale, Tardieu Scale and Functional Assessment

Spasticity is often described as “tightness,” but a useful clinical assessment must go further than asking whether a limb feels stiff. Clinicians need to understand what happens when a muscle is stretched at different speeds, whether the restriction is dynamic or fixed, how the pattern changes during activity, and whether it actually interferes with comfort, care or function. No single score answers all of those questions.

The Modified Ashworth Scale and the Tardieu or Modified Tardieu Scale are among the best-known bedside tools. They measure related but different features, and both have limitations. A complete assessment therefore combines examination findings with range-of-motion testing, observation of movement, the person’s priorities and meaningful functional outcomes.

Contents

• Why measure spasticity?
• Modified Ashworth Scale
• Tardieu and Modified Tardieu Scales
• How the scales differ
• Functional assessment
• Making repeat measurements useful
• Questions to ask after an assessment

Why measure spasticity?

Measurement helps clinicians describe a baseline, identify changes over time and decide whether an intervention has produced a meaningful effect. It may contribute to decisions about rehabilitation, positioning, oral medication, botulinum toxin injections or an intrathecal baclofen assessment. It can also help distinguish a velocity-dependent muscle response from fixed shortening or joint restriction.

However, measuring tone is not the same as measuring the whole person. Two people with the same score may have very different experiences. One may walk independently and have little discomfort; another may struggle with hygiene, sleep or transfers. Even in the same person, a limb may feel different during a calm clinic examination than during hurried walking, emotional stress, pain or fatigue.

Current clinical guidance therefore supports a multidimensional, goal-based approach. The examination should answer practical questions: Which muscles appear overactive? Is there a rapid stretch response? How much passive range is available? Is weakness or poor selective control contributing? Does the pattern help or hinder activity? What outcome matters to the person and caregivers?

The Modified Ashworth Scale

The Modified Ashworth Scale, usually abbreviated as MAS, is widely used because it is quick and requires no special equipment. The examiner moves a relaxed joint through its available range and grades the resistance felt. Scores usually run from 0 to 4, with an additional 1+ category.

• 0: no increase in muscle tone.
• 1: a slight increase, with a catch and release or minimal resistance near the end of the range.
• 1+: a slight increase with a catch followed by minimal resistance through less than half of the remaining range.
• 2: a more marked increase through most of the range, although the affected part still moves easily.
• 3: a considerable increase that makes passive movement difficult.
• 4: the affected part is rigid in flexion or extension.

The apparent simplicity is useful, but it can also be misleading. The examiner is rating resistance to passive movement, not directly measuring the neural stretch reflex. Resistance may come from spasticity, shortened muscles, connective-tissue stiffness, joint changes, pain, guarding or a mixture of factors. The categories are also ordinal: the difference between scores 1 and 2 is not necessarily equal to the difference between 2 and 3.

Research has found variable agreement between examiners, although reliability can improve when clinicians use a standardized protocol and test familiar muscle groups. For follow-up, it is helpful to record the muscle group, side, joint position and testing method rather than documenting only “MAS 2.” A one-grade change should be interpreted cautiously and alongside other findings.

What the MAS can and cannot tell you

The MAS can provide a fast clinical description of passive resistance and can help a team communicate about change. It cannot, by itself, show whether the person walks more safely, opens the hand more easily or experiences less pain. It also does not formally compare slow and fast stretches, even though velocity dependence is central to the clinical definition of spasticity.

The Tardieu and Modified Tardieu Scales

The Tardieu approach was developed to examine muscle response at specified stretch velocities. In commonly used versions, the clinician moves the limb slowly to estimate the full passive range and then more quickly to identify a catch, clonus or other muscle reaction. A goniometer may be used to record joint angles.

Terminology varies by version, but two measurements are especially important. R2 generally represents the maximum passive range obtained during a slow stretch. R1 is the angle at which a catch or resistance is first detected during a fast stretch. The quality of the muscle reaction may also be graded, from no resistance through a brief catch to sustained clonus or an immovable joint.

The relationship between R1 and R2 can be clinically informative. A substantial gap may suggest that a considerable part of the restriction is dynamic and velocity dependent. A small gap, especially when the slow passive range is limited, may suggest a stronger fixed mechanical component such as muscle shortening or contracture. This is not a stand-alone diagnosis, but it can help guide further examination and treatment planning.

The Tardieu method aligns more closely with the velocity-dependent concept of spasticity than the MAS. Still, it demands consistent positioning, clear control of stretch speed and accurate angle measurement. Systematic reviews have reported mixed or limited evidence for reliability in some populations and muscle groups. Results should therefore be considered part of a broader assessment rather than an objective truth detached from clinical context.

Modified Ashworth versus Tardieu: how do they differ?

Question	Modified Ashworth	Tardieu approach
What is mainly recorded?	Amount of resistance during passive movement	Quality and angle of reaction at different stretch speeds
How long does it take?	Usually brief	Usually longer and more technique-dependent
Does it formally address velocity?	Not adequately	Yes
Can it separate dynamic from fixed restriction?	Only to a limited extent	R1 and R2 may help estimate the relative contribution
Main limitation	Resistance is not specific to spasticity	Standardization and reliability can be challenging

The two scales are not interchangeable. A team may use one consistently for serial follow-up or use both when the distinction between dynamic overactivity and fixed restriction matters. Neither should be used as the sole reason to begin or intensify treatment.

Functional assessment: measuring what matters in daily life

A spasticity assessment should connect body findings to real activities. Clinicians may observe walking, stair use, transfers, reaching, grasp and release, dressing, toileting, hygiene, wheelchair positioning or sleep-related spasms. The relevant activity depends on the person’s diagnosis, age, environment and priorities.

Assessment may include strength, selective motor control, coordination, sensation, balance, endurance and active range of motion. Video recorded with consent can help compare movement before and after treatment. Timed tests or standardized upper-limb and mobility measures may be useful, but the selected tool should match the intended goal.

Goal Attainment Scaling is one way to define individualized outcomes. A goal might be easier cleaning of the palm, wearing an orthosis for a specified period, walking a defined distance with fewer interruptions, or sleeping through the night with fewer painful spasms. The expected result is described before treatment, making follow-up more meaningful than asking only whether tone decreased.

Passive goals are important too. A person may not gain active hand opening but may experience less pain, improved skin care or easier dressing. These outcomes can have substantial value. Conversely, reducing tone may not be beneficial if the person relies on stiffness to stand or transfer. Functional observation helps reveal that trade-off.

Other information that affects interpretation

• Pain, anxiety, fatigue and temperature can change muscle response.
• Constipation, urinary infection, skin injury or an uncomfortable brace may temporarily increase spasms.
• Medication timing can alter findings.
• Position of the head, trunk and neighboring joints can influence the tested muscle.
• Dystonia, rigidity and voluntary co-contraction may resemble or coexist with spasticity.
• Fixed contracture limits range even when neural overactivity is reduced.

For these reasons, an unexpected change should prompt a review of possible triggers and the broader neurological and musculoskeletal examination. You can read more about the symptoms and assessment of spasticity and the conditions associated with spasticity.

How to make repeat measurements more useful

Consistency improves the value of serial assessment. When possible, the same clinician should use the same method, muscle position, stretch direction and speed. The record should identify the side and muscle group, not only the joint. It is also useful to note pain, recent activity, medication timing and any illness or trigger that could influence the result.

Timing should reflect the intervention. Follow-up after botulinum toxin treatment may examine both the expected period of peak effect and whether the agreed activity goal improved. Reviews of oral medication should consider alertness, weakness and participation as well as tone. After rehabilitation, active performance and carryover into daily routines may matter more than a passive score.

A result is most useful when it changes a decision. If the score is collected but does not inform goals, treatment selection or follow-up, its value is limited. Current consensus guidance emphasizes repeated, person-centered assessment rather than a single isolated number.

Questions to ask after a spasticity assessment

• Which muscles and activities were assessed?
• Was the restriction mainly dynamic, fixed or mixed?
• What factors besides spasticity may be affecting movement?
• What practical goal would treatment aim to improve?
• How and when will progress be measured?
• Could reducing tone remove strength or stability that is currently useful?
• What changes should prompt an earlier review?

Frequently asked questions

Can I measure spasticity at home?

Formal MAS or Tardieu scoring requires training and consistent technique. Families can still record valuable observations, such as when spasms occur, whether dressing or hygiene is harder, how sleep changes and what triggers worsening. A short diary or video, recorded safely and with consent, can support a clinical review.

Is a higher MAS score always worse?

No. A higher score indicates more passive resistance during that examination, but the effect on function varies. Some tone may assist standing or transfers, while a lower score can coexist with weakness or poor motor control. The meaning depends on symptoms and goals.

Which scale is more accurate?

The Tardieu approach reflects velocity dependence more directly, but neither scale is perfect. Choice depends on the clinical question, population, examiner training and need for repeatability. The strongest assessment combines an appropriate scale with range, movement and functional outcomes.

Does improvement mean the score must fall?

Not necessarily. A person may achieve easier care, less pain or better movement without a large change in a tone score. Treatment success should be judged against the goals set before intervention, together with safety and adverse effects.

Continue reading

Explore what spasticity is, review available spasticity treatments, and learn how rehabilitation supports meaningful goals.

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Medical disclaimer: This article is provided as a public information service and is not a substitute for diagnosis, treatment or individualized advice from a qualified healthcare professional. Do not start, stop or change treatment based on this page.

Last updated: September 2026. The content was prepared using current consensus guidance and peer-reviewed evidence on clinical spasticity assessment. This page has not been medically reviewed by an identified healthcare professional.