Determination of prevalence of glenoid bony lesions after recurrent anterior shoulder dislocation using the 3-D CT scan

  Background : Glenoid bone damages consisting of anterior rim erosion and bony avulsion are very important in decision making for treatment of recurrent dislocation in shoulder joint. This study was aimed to determine the prevalence of these damages in patients with anterior recurrent shoulder dislocation.   Methods : The study was a cross-sectional study evaluating patients with unstable shoulder joint. Glenoid bone damage was assessed using three dimensional (CT) scan implementing either glenoid width index or by Pico method.   Result : Ninety two patients were assessed by glenoid width index and 19 by PICO. Among the first group, 6 patients (6%) had intact shoulder joint and 86 patients (93%) had glenoid lesion including 56 (60.9%) erosions and 30 (32.6%) with bony Bankart. In this group, 60 (65%) patients had Hill-Sachs lesion. Using Pico evaluation, 8 (42%) had bony Bankart, 9 (47%) erosion and 2 (10%) no lesion, and 8 (42%) Hill-Sachs.   Conclusion : There was no significant correlation between severities of glenoid bone loss with patients'frequency of dislocations. Patients with convulsion-induced shoulder dislocation had the most severe bone loss. The CT scan should be done early in recurrent dislocation because severe bony damage could occur even after few dislocations. The overall prevalence of glenoid bone damage including bony Bankart and erosion are high in recurrent anterior dislocation. This is particularly emphasized in patients with seizure.