Surgical options for the treatment of simple bone cyst in children and adolescents

Background: There are several treatment options for simple bone cysts, with treatment depending mainly on the experience and preference of the surgeon and the extension and location of the cyst. Objectives: To assess our experience with the surgical treatment of bone cyst lesions in pediatric patients at one institution by the same group of surgeons. Methods: The study group comprised 60 patients (43 boys, 17 girls) treated surgically for monostatic lesions between January 2002 and July 2007. The mean age at surgery was 11.8 years (range 4-17 years). Mean follow-up was 4.2 years. Most of the lesions were located at the proximal humerus. Patients were divided into five groups according to treatment method: a) corticosteroids (methylprednisolone 40-80 mg) (n=26); b) curettage and bone grafting (fibula or iliac crest) (n=16); c) aspiration of the bone cavity and subsequent bone marrow transplantation (n=10); d) internal preventive fixation using an elastic stable intramedullary nail (n=5); and e) curettage and implantation of a synthetic cancellous bone substitute (pure beta-tricalcium phosphate substitute, ChronOS®, Synthes, Switzerland) (n=3). Results: Treatment success was evaluated by the Capanna criteria. Successful results were observed in 68% (18 complete healing, 23 healing with residual radiolucent areas), 30% recurrence rate, and no response to treatment in one patient (2%). We recorded recurrence in 50% of the children treated by corticosteroid injection, and one child did not respond to treatment. Conclusions: The best results were achieved in children treated by curettage and the subsequent use of an osteoconductive material, and in children treated with elastic intramedullary nail fixation. Despite our limited experience with calcium-triphosphate bone substitute, the treatment was mostly successful. Because of the short follow-up, further observation and evaluation are necessary.