Arthroscopic Assessment of Glenoid Bone Loss

Background: Clinical decision-making for treating anterior shoulder instability relies on accurate glenoid bone loss quantification precision. This study aimed to assess the accuracy of the axial view of a 2-D CT scan compared with arthroscopy to measure glenoid bone loss following 3-D CT scanning.Method: This study was performed from March 2019 to February 2020 on patients who presented to the shoulder clinic of a referral teaching hospital in Tehran, Iran. Eighteen patients with at least one history of unilateral anterior shoulder dislocation without shoulder surgery participated in the study. Before surgery, the qualified participants had their injured and uninjured shoulders CT scanned. The Griffiths index was used to estimate the size of glenoid bone loss in CT scan imaging. Subsequently, the affected shoulders were arthroscopically evaluated, and glenoid bone loss was measured using a standard probe.Results: Among the 18 participants, glenoid bone loss was underestimated for 11 patients (61.1%) in CT scans compared to arthroscopy. The mean +/- SD of glenoid bone loss percentage on CT scan (9.5% +/- 4.9%) was significantly lower than on arthroscopy (11.7% +/- 3.9%, p = 0.04). Nevertheless, Pearson's correlation showed a significantly moderate correlation (r = 0.55, p = 0.01) between arthroscopic and CT scan measurements of glenoid bone loss. Conclusion: Our findings indicate that glenoid bone loss width measurement via the axial view of a CT scan should not be considered a reliable method to measure glenoid bone loss.