Assessing the Reliability of Echo Intensity of Craniovertebral Muscle Group using B-Mode Ultrasound: A Technical Note

An acceptable reliability is needed for each scale and a valid decision-making process. Ultrasonography is a simple, cost-effective, and accessible tool compared to magnetic resonance imaging (MRI) to assess echo intensity (EI) as a biomarker of muscle function in neck musculoskeletal problems. However, no evidence is available regarding the reliability of neck muscle echogenicity according to rehabilitative ultrasonography in clinical studies on forward head posture (FHP). We determined the reliability of neck muscles EI in individuals with and without FHP. Transverse images of deep neck flexors (Longus Coli) and suboccipital (Rectus capitis posterior minor) muscles were acquired from 20 individuals with FHP and 20 controls in one session. The intraclass correlation coefficient (ICC), minimum detectable change (MDC), and standard error of measurement (SEM) for EI were measured in this study. The ICC, SEM, and MDC ranges were 0.50 - 0.51, 2.73 - 3.41, and 7.56 - 9.46 for the Longus colli muscle and 0.48 - 0.49, 3.29 - 4.98, and 9.13 - 13.81 for the rectus capitis posterior minor (RCPm) muscle, respectively. Based on the present findings, EI showed acceptable reliability; therefore, it can be used for assessment of neck muscle morphology.