The Modified Tardieu Scale (MTS) is a clinical tool used to assess spasticity by measuring muscle response to passive stretch at different speeds. Unlike the Modified Ashworth Scale (MAS), the MTS differentiates between spasticity (velocity-dependent hypertonia) and fixed contractures.
Assessment Method
The muscle is stretched at two different speeds:
- V1 (Slow Stretch): Measures the full passive range of motion (R2).
- V3 (Fast Stretch): Identifies the first point of resistance (R1), indicating spasticity.
Key Measurements
- R1 (Spasticity Angle): The point where the muscle first resists movement during a fast stretch.
- R2 (Passive Range of Motion): The maximum joint range when stretched slowly.
- R2 – R1 Difference: A larger difference suggests dynamic spasticity, which may respond to botulinum toxin or other treatments.
Scoring System (0–4 Scale, Based on Muscle Reaction):
- 0 – No resistance.
- 1 – Slight resistance, no clear catch.
- 2 – Clear catch at a specific angle, followed by release.
- 3 – Fatigable clonus (<10 seconds) when stretched rapidly.
- 4 – Unfatigable clonus (>10 seconds) when stretched rapidly.
- 5 – Joint is immobile (contracture).
Accessing the MTS
A comprehensive training manual for the MTS is available through Assesschild:
Pros of using the MTS
- Velocity-Specific Assessment: The MTS evaluates muscle responses at different stretch speeds, distinguishing between neural (spasticity) and non-neural (contracture) components of muscle tightness.
- Detailed Spasticity Profiling: By measuring the angle of muscle reaction (R1) and the full passive range of motion (R2), the MTS helps in identifying the dynamic component of spasticity, aiding in targeted intervention planning.
- Enhanced Sensitivity: The scale’s ability to assess reactions at multiple velocities may offer a more nuanced understanding of spasticity compared to other measures.
Cons of the MTS
- Time-Consuming: Administering the MTS can be more time-intensive than other spasticity assessments, which may be challenging in busy clinical settings.
- Training Requirements: Accurate application of the MTS necessitates proper training and experience, potentially limiting its use among less experienced clinicians.
- Subjectivity: Despite its structured approach, the MTS involves subjective judgment, which can affect inter-rater reliability.
For clinicians interested in implementing the MTS, it is advisable to undergo formal training to ensure accurate assessment and interpretation. The training manual provided by Assesschild offers detailed guidance on the proper administration of the scale.
Advantages Over MAS
- Differentiates spasticity from contractures.
- Provides quantitative data for treatment decisions.
- More reliable and sensitive for assessing dynamic spasticity.
Clinical Importance
The MTS is widely used in children with cerebral palsy (CP) to guide interventions like botulinum toxin injections, physiotherapy, and surgical treatments.
Comparison of SCALE, MAS, and MTS in Cerebral Palsy Assessment
| Feature | Selective Control Assessment of the Lower Extremity (SCALE) | Modified Ashworth Scale (MAS) | Modified Tardieu Scale (MTS) |
|---|---|---|---|
| Purpose | Assesses selective voluntary motor control (SVMC) and ability to move joints independently. | Measures muscle tone and resistance to passive movement. | Evaluates spasticity at different speeds to differentiate it from contractures. |
| Key Focus | Voluntary movement control and synergy patterns. | Muscle stiffness and hypertonia. | Spasticity dynamics and range of motion limitations. |
| Measurement Method | Child performs active movements at hip, knee, ankle, subtalar, and toe joints. | Passive limb movement at a single speed. | Passive movement at slow (V1) and fast (V3) speeds. |
| Scoring Scale | 0-2 per joint (higher score = better selective control). | 0-4 scale (higher score = more tone/stiffness). | 0-5 scale (higher score = more spasticity/clonus). |
| Spasticity vs. Contractures | Not assessed. Focuses on movement control. | Cannot differentiate between spasticity and contractures. | Can differentiate (if R1 and R2 differ, spasticity is present). |
| Velocity Dependency | No (assesses voluntary movement control). | No (measures resistance at a single speed). | Yes (tests response to different movement speeds). |
| Best For | Identifying motor control issues and synergistic movement patterns. | Quick spasticity screening, simple to use. | More detailed spasticity assessment, guiding interventions. |
| Limitations | Requires cognitive ability to follow movement instructions; may not work for children with severe motor impairments. | Subjective, does not account for velocity-dependent spasticity. | More complex, requires trained assessors for accuracy. |
Which One to Use?
Use MTS when a detailed spasticity evaluation is needed, especially for treatment planning (e.g., botulinum toxin, surgery).
Use SCALE to evaluate voluntary movement control and detect abnormal motor synergies.
Use MAS for a quick muscle tone assessment when screening for spasticity.