Poster 156: Intraobserver and Interobserver Reliability in Glenoid Track Measurement

Abstract

Objectives: The purpose of our study was to determine the accuracy and reliability of measuring on- and off-track lesions within our institution using the circle line method. Methods: Electronic medical records between 2009 and 2019 were reviewed for active-duty military personnel who underwent a Latarjet or had recurrent dislocations of the shoulder joint. Advanced imaging (CT and/or MRI) was reviewed for glenoid and humeral head bone loss; patients with both glenoid and humeral head bone loss were included in the study. Measurement of the Hill-Sachs lesion (HSL) was standardized prior to the start of the study and measured as described by Di Giacomo. Results: All surgeons completed the review of all 38 images for 2 measurements. Intraobserver reliability was shown to have moderate reliability amongst all reviewers (intraclass correlation coefficient [ICC] = 0.459; p < 0.001). The kappa (κ) value for interobserver reliability amongst all reviewers was moderate for glenoid diameter (ICC = 0.567; 95% CI, 0.474-0.663), moderate for glenoid defect (ICC = 0.61; 95% CI, 0.517-0.702), poor for HSL (ICC = 0.328; 95% CI, 0.232-0.441), moderate for glenoid track (ICC = 0.668; 95% CI, 0.584-0.75) and fair for HSL on- and off-track assessment (κ = 0.267, p < 0.001). Conclusions: The intraobserver reliability of measuring advanced imaging for shoulder instability using the circle line method is overall good; however, the interobserver reliability is moderate to poor.