Clinical evaluation of the anterior translation of glenohumeral joint using ultrasonography: an intra- and inter-rater reliability study.

Objective: The aim of this study was to investigate the intra- and inter-rater reliability of ultrasonography (US) to measure anterior translation of the humeral head (ATHH) among healthy subjects and patients with sacroiliac joint dysfunction.
Methods: The study included a total of 22 shoulder joints from 11 subjects. Six subjects were healthy and 5 had sacroiliac joint dysfunction. Anterior translation of the humeral head was measured twice using US by two different investigators. Intraclass correlation coefficient (ICC3,1), standard error of measurements (SEMs), coefficient of variations (CVs) and Bland-Altman plot were used as analytical tests to investigate intra- and inter-rater reliability, amount of error and agreeability of the measurements between investigators.
Results: Intraclass correlation coefficient was 0.94, showing a high level of intra-rater reliability of the first investigator with SEMs (0.01 cm) and CV (5.1%) in measuring ATHH. Intra-rater reliability of the second investigator was 0.84 with SEMs (0.03 cms) and CV (9.6%), indicating a high level of reliability. Inter-rater reliability was high, with an ICC value of 0.92 with SEMs (0.02 cms) and CV (5.9%).
Conclusion: The use of US as a measurement of ATHH has good levels of intra- and inter-rater reliability in clinical practice.