Myotonometry as a measure to detect myofascial trigger points: an inter-rater reliability study

Area of Science:

• Biomedical Engineering
• Musculoskeletal Physiology
• Rehabilitation Science

Background:

• Traditional methods for identifying skeletal muscle mechanical properties, such as myofascial trigger points (MTrPs), are often impractical for routine clinical application.
• Myotonometry presents a viable, noninvasive alternative for assessing muscle biomechanics, though its application to MTrPs has been underexplored.

Purpose of the Study:

• To differentiate mechanical properties between latent MTrPs and their associated taut bands using myotonometry.
• To evaluate the inter-rater reliability of myotonometric measurements for MTrPs.
• To explore the correlation between myotonometry and passive isokinetic dynamometry in assessing muscle function.

Main Methods:

• Fifty participants with latent medial MTrPs in the soleus muscle were assessed using a MyotonPRO myotonometer.
• Mechanical properties of the MTrP and taut band areas were measured.
• Passive resistive torque and extensibility of the triceps surae were evaluated using a Kin-Com dynamometer.

Main Results:

• Taut bands exhibited significantly higher stiffness compared to MTrPs (P < 0.05).
• Myotonometric measurements demonstrated good inter-rater reliability (ICC > 0.75) with low measurement error (SEM% < 10%, MDD < 20%).
• Fair correlations (r = -0.29 to 0.48, P < 0.05) were observed between myotonometric and passive isokinetic parameters.

Conclusions:

• Myotonometry is a reliable instrument capable of quantifying mechanical property variations in myofascial tissues.
• This noninvasive technique shows potential for the clinical assessment of myofascial pain syndromes, warranting further research.