This study evaluated the feasibility and efficacy of a percutaneous injection of a mixture of autogenous bone marrow and crushed cancellous bone allografts for the treatment of simple bone cysts.

Fifteen patients with a simple bone cyst were enrolled in this study. The mean age was 13.5 years (range, 4-32 years), and the mean follow-up period was 13.2 months (range, 8-19 months). The radiographic signs of the resolution of the cyst were categorized as healed, healed with a defect, persistent and recurrent. The groups of healed and healed with a defect were designated the positive response groups.

Fourteen patients responded to the treatment. Nine patients showed complete healing that was first seen radiographically at 3 months (range, 1-6 months). Five patients showed healing with a defect, but no patient required a second injection because the cysts were small and did not cause functional pain. There was no correlation between clinical responses and age, gender, location, cyst index and previous treatment modalities. One patient had a pathological fracture, which was treated successfully by open bone grafting with flexible intramedullary nailing.

A percutaneous injection of a mixture of autogenous bone marrow and a crushed cancellous bone allograft may be an effective treatment for simple bone cysts.