Percutaneous autologous bone marrow grafting for simple bone cysts.

Twelve patients with simple bone cysts treated by percutaneous autologous bone marrow grafting were studied prospectively to evaluate the radiographic healing of the cysts, complications, and clinical outcome. The procedure included percutaneous aspiration of the cyst's fluid and the injection of the autologous bone marrow into the cyst cavity, which was aspirated from the posterior iliac crest. The mean volume of the lesions was 51.2 cubic centimeters (27 to 74 cc). The mean follow-up time was 23 months (range: 18 to 38 months). Complete healing occurred in two of the patients. Three cysts had residual cystic defect in which two required curettage and bone chip grafts. Six cases recurred. One patient failed to show any signs healing. We concluded that factors such as the size, multi-loculation, and completeness of the filling of the cyst with bone marrow grafting might influence the postoperative results of the treatment of simple bone cysts with bone marrow injection. We found more favorable result with unilobular, small cysts. Therefore, we believe that this method of treatment should be applied to carefully selected patients.