SCAPULAR FRACTURES: COMPARISON OF GLENOPOLAR ANGLE MEASUREMENT USING 3D COMPUTED TOMOGRAPHY AND CONVENTIONAL...

To compare the interobserver and intraobserver reliability of glenopolar angle (GPA) measurement in scapular fractures using conventional radiography (2D) and three-dimensional computed tomography (3D-CT).

This retrospective observational study included 33 patients with fractures of the scapular body or neck treated between 2016 and 2023. Anteroposterior radiographs and 3D-CT scans obtained at the time of diagnosis were included. The GPA was measured by eight independent evaluators, and data were analyzed using the intraclass correlation coefficient (ICC), according to the criteria proposed by Koo and Li, with SPSS software.

The mean interobserver ICC for GPA measurement was 0.959 (95% CI: 0.934-0.977) for radiography and 0.971 (95% CI: 0.953-0.984) for 3D-CT, indicating excellent reliability for both methods. Individual intraobserver reliability ranged from 0.598 to 0.869, with five evaluators demonstrating good reliability and three showing moderate reliability. The sample consisted predominantly of males (93.9%), with a mean age of 39.6 years (range: 19-78 years), and 24.2% of patients underwent surgical treatment.

GPA measurements obtained by radiography and 3D-CT demonstrated high interobserver reliability, with slight superiority of 3D-CT. Both methods are valid, although 3D-CT may be preferable in cases requiring greater angular precision. Level of Evidence: III; Retrospective observational study.