Gorham-Stout syndrome of the shoulder.

Introduction: Gorham-Stout syndrome (GSS) is a rare but severe subtype of idiopathic osteolysis. There are no guidelines for the treatment of GSS. We analysed different diagnostic and therapeutic regimes and we describe the sucessful treatment of GSS considering individual patient factors.

Methods: We diagnosed three patients with shoulder-specific GSS using clinical, radiological and histopathological examinations. Two out of three patients with similar clinical appearances were treated non-operatively. One patient was treated by reverse shoulder arthroplasty. All patients were analysed retrospectively using clinical and radiological evaluation with a mean follow-up of 42 (range 30-50) months.

Results: Two patients had few symptoms of GSS and were treated conservatively. One patient underwent arthroplasty, with a good clinical result. No additional therapy, such as radiation or anti-resorptive medications, was needed for the stable fixation of the prosthesis and the termination of osteolysis. In all patients we found good clinical outcomes with high patient satisfaction.

Discussion: GSS is diagnosed after exclusion of infectious, malignant, and systemic disorders. The diagnosis should be supported by clinical, radiological, and histopathological characteristics of patients. Different humoral and cellular changes have been reported in GSS, but lack sufficient supporting evidence. GSS is associated with angiomatous and lymphatic malformations. The changes in GSS and the theories of its pathophysiology may reveal.