Arthroscopic assessment of glenoid bone defect in patients with anterior shoulder instability

Abstract

Purpose The purpose of this study was to assess the reliability of arthroscopic estimation of anterior glenoid bone defect in patients with anterior shoulder instability, by comparing it with anteroposterior diameter equation method in computed tomography (CT) glenoid en-face view with head subtraction. Patients and methods Thirty patients with anterior shoulder instability underwent shoulder CT glenoid en-face view scans and were found to have anterior glenoid bone defect. The anterior glenoid bone loss of each patient was studied using the anteroposterior distance from the center of a best-fit circle drawn on the inferior portion of the glenoid. Arthroscopic estimation of the anterior glenoid bone defect was done in all those patients as a part of the planned final procedure. The mean percent bone loss studied in CT was compared with arthroscopy to determine the reliability of arthroscopy in the measurement of anterior glenoid bone defect. Results The mean percentage of anterior glenoid bone defect calculated with CT diameter equation method was 17.3±9.7, whereas the mean percentage of arthroscopic estimation of anterior glenoid bone defect was 22.55±9.9, which shows statistically significant difference (P Conclusion Our finding suggests that arthroscopy significantly overestimates anterior glenoid bone defect compared with CT glenoid en-face view anteroposterior distance method, and the surgeons should not relay on arthroscopic measurement of the defect to plan for surgery.