Reliability of Panoramic Ultrasonography in Assessing Pectoralis Minor Morphology: An Intra- and Inter-Rater Study...

Objectives: This study aimed to examine the intra- and inter-rater reliabilities of panoramic ultrasonographic measurements of the pectoralis minor length (Pm_L), pectoralis minor thickness (Pm_T), and pectoralis minor cross-sectional area (Pm_CSA). Methods: Twenty young male participants aged 19-35 years were recruited for this study. All participants had asymptomatic rounded shoulder posture (RSP), with a mean acromion-to-table distance of 59.316 ± 9.631 mm. Longitudinal panoramic scans of the Pm of the dominant arm were acquired in three trials of four measurements for all participants. The first two measurements were examined by the same rater on the same day, and the third measurement was performed by a different rater. The same procedure was carried out by the first rater after 30 days for inter-day reliability. Intraclass correlation coefficients (ICCs), standard errors of measurement (SEMs), and minimal detectable changes (MDCs) were calculated to estimate the reliabilities. Results: The intra- and inter-rater reliabilities of Pm_L, Pm_T and Pm_CSA were excellent (all ICC > 0.932; all SEM < 7.4%; all MDC < 20%). Bland-Altman plots demonstrated good agreement with nearly zero mean differences between measurements. Conclusions: Using panoramic ultrasonography to measure Pm_L, Pm_T and Pm_CSA may be considered a reliable method with excellent inter-day, intra- or inter-rater reliabilities.