Applying the V.E.R.A. method to entheses of the humerus: An assessment of repeatability and reproducibility

The “Validated Entheses-based Reconstruction of Activity” (V.E.R.A.) method has proven to be a reliable method for the quantification and analysis of entheses. However, this method has only been successfully applied to human hand bones and animal long bones. This study tests the general applicability of the V.E.R.A. method to the human humerus, focusing on evaluating its reliability and repeatability. The sample included 23 humeri of unknown origin and background. The V.E.R.A. method was applied to six entheses of the humerus, comprising the subscapularis, supraspinatus, infraspinatus, teres minor, common extensor origin, and common flexor origin. Lin's concordance correlation coefficient (CCC) and percentage of error statistics were used to measure intraobserver error. Interobserver error was assessed through analysis of variance (ANOVA) tests, the intraclass correlation coefficient (ICC), and Lin's CCC. Intraobserver rates were between 1.83% and 3.23%. Interobserver error values were excellent, with no significant differences found in the ANOVA tests; Lin's CCC values were all above 0.90, with only the common extensor origin being 0.87; and ICC values were all above 0.97. Our results showed that the V.E.R.A. method is highly reliable and reproducible for the six entheses of the human humerus selected for this study. These results demonstrate the vast potential for the V.E.R.A. method to be applied to other parts of the human skeleton.