Purpose: Posterior shoulder dislocations are rare, and are usually the result of seizures. Anterior defects of the humeral head known as "reverse Hill-Sachs lesions" may increase the risk of recurrent dislocation and are difficult to treat. We developed a percutaneous technique for reduction of the dislocation or reduction of the anterior impaction fracture, using percutaneous balloon dilatation and cement fixation.
Methods: From 2009 to 2012, three patients aged 33, 72 and 75 years were admitted to our institution with a posterior shoulder dislocation showing an anterior "reverse Hill-Sachs" impaction fracture. One case was bilateral (four fractures). Patients were operated upon in the sitting position; the humeral head was stabilised by external fixator pins during balloon inflation. Reduction or filling of the defect was obtained in all cases. All patients were followed up and two patients (three fractures) were examined after one year by an independent observer. The clinical results were assessed using the Constant score and the RAND-36 physical components score. A computed tomography (CT) scan was obtained in all patients before and after the operation and at the latest follow-up.
Results: At three months postoperatively, all patients had resumed work or daily life activities with no limitation. The mean Constant score was 71 and RAND-36 score was 85.5. After one year, the mean Constant score was 73 and the RAND-36 score was 86.4 for the two patients who had sufficient follow-up. On the postoperative radiograph and CT scan, sphericity of the humeral head was restored, and the reverse Hill-Sachs impaction was filled or reduced in all cases. There was no recurrent dislocation.
Conclusion: Based on this small series, we believe that this technique should be added to our current armamentarium for posterior shoulder dislocations showing a deep impaction fracture of the humeral head that are at risk for recurrent dislocation.