Correlation between Bankart and Hill-Sachs lesions in anterior shoulder dislocation

Bankart lesions and Hill-Sachs lesions are commonly associated with anterior shoulder dislocations. The presence of Bankart lesion indicates the need for surgical repair. Magnetic resonance imaging (MRI) has been shown to be sensitive in detecting these two lesions. The aim of this study is to investigate the correlation between Bankart lesions and Hill-Sachs lesions on MRI for patients with traumatic anterior shoulder dislocations.

Between 2003 and 2005, 61 patients from Alfred and Sandringham Hospitals had an MRI as part of the investigation for traumatic anterior shoulder dislocations. The MRI scans were reviewed and subsequently confirmed by a radiologist to show the presence or absence of Bankart and Hill-Sachs lesions. The data were then analysed by a statistician.

Although patients with one of these lesions were more than two-and-a-half times as likely to have the other, small study numbers precluded this result from achieving statistical significance. (odds ratio, 2.67 (0.83-8.61), P = 0.10). Younger age was a strong predictor of a recurrence of shoulder dislocation (odds ratio, 0.93 (0.89-0.98), P = 0.005). The presence of Bankart or Hill-Sachs lesions on MRI for the primary shoulder dislocation group was similar to the recurrent group (73% vs. 72% for Bankart lesion and 67% vs. 70% for Hill-Sachs lesion).

There is a strong correlation between both lesions. This apparent trend can be useful in predicting the presence of a Bankart lesion when a Hill-Sachs lesion is identified on a plain radiograph. This study suggests the consideration of surgical repair after identification of a Hill-Sachs lesion on plain radiographs, especially for younger patients where the rate of re-dislocation is high.