Reliability of measurement of neck and back muscle mechanical properties using MyotonPRO: A systematic review

MyotonPRO allows for the non-invasive assessment of the mechanical properties of muscles (stiffness, tension and viscoelastic properties of the muscle). It has found use in various anatomical areas, including the neck and back. Since neck and back pain are common musculoskeletal complaints an accurate and reliable device is essential for accurate diagnosis.

The purpose of this study was to review the literature to determine whether MyotonPRO device is a reliable tool for estimating mechanical properties of the neck and back muscles.

A literature search was performed using PubMed, Science Direct and Pedro databases using the terms "MyotonPRO" and "reliability". All studies, irrespective of the tests and methodologies employed, were included in this systematic review. The intraclass correlation coefficient (ICC) was classified as excellent (>0.90), good (0.75-0.90), moderate (0.50-0.75), or poor (<0.50).

Fifteen papers met the eligibility criteria. Intra-rater, inter-rater and time interval reliability were investigated in nine, nine and seven studies, respectively. Most of the outcomes (16) reported good to excellent reliability (intraclass correlation coefficient (ICC) > 0.75) with exceptions for moderate to excellent (5 outcomes, ICC >0.51) and poor to excellent (4 outcomes, ICC > -0.15) regardless of participant gender, age, site of measurement or measured muscle. Overall ICC values ranged from -0.15 to 0.99 for intra-rater, inter-rater, and test-retest reliability.

MyotonPRO device should be considered an effective measurement tool useful in testing the mechanical properties of soft tissues in the back and neck.