Giant solitary synovial osteochondromatosis of the elbow causing ulnar nerve neuropathy: a case report and review of literature

INTRODUCTION: Giant or solitary osteochondroma is part of a rare disorder known as synovial osteochondromatosis. It forms part of a spectrum of disease characterized by metaplastic changes within the joint synovium that are eventually extruded as loose bodies. It has been suggested that solitary synovial osteochondroma forms as progression of synovial osteochondromatosis through a process of either coalescence of multiple smaller bodies or the growth of a dominant synovial osteochondroma. Previous studies have shown that it occurs as a late phase of the disease. We report a rare case of giant synovial osteochondromatosis at the elbow causing ulnar nerve neuropathy and mechanical symptoms which has not been previously reported in the literature. CASE REPORT: We report a case of a 56 year old Western European gentleman who presented with ulnar nerve neuropathy and swelling behind the elbow. The patient underwent MR imaging and subsequent biopsy that demonstrated synovial osteochondromatosis. Initially the patient declined surgery and opted for a watch and wait approach. Five years later he returned with worsening symptoms and underwent successful surgical resection of a giant solitary synovial osteochondroma. CONCLUSION: The unique outcome in our patient despite the long interval between presentation and surgical treatment resulted in early full resolution of symptoms within a short period. It may suggest an improved prognosis as compared to multiple synovial osteochondromatosis in terms of mechanical and neurological outcomes.