Is curettage and high-speed burring sufficient treatment for aneurysmal bone cysts?

Background: To decrease the recurrence rate after intralesional curettage for aneurysmal bone cysts, different adjuvant treatments have been recommended. Liquid nitrogen spray and argon beam coagulation have provided the lowest recurrence rates, but unlike the high-speed burr, these adjuvants are not always available in operating rooms.
Questions/purposes: We asked: (1) Is high-speed burring alone sufficient as an adjuvant to curettage with respect to recurrence rates? (2) What is the complication rate from this technique? (3) What are the risk factors for local recurrence?
Methods: A retrospective review of the database of the University Musculoskeletal Tumor Unit and the private files of the senior author (EHW) for a period of 19 years (1993-2011) was performed to identify all patients histologically diagnosed with primary aneurysmal bone cyst. During that period, patients with aneurysmal bone cysts were treated with intralesional curettage, burring, and bone grafting if the lesions showed an adequate cortical wall or a wall with thinned out portions which could be reconstructed with bone grafting. Based on those indications, we treated 54 patients for this condition. Of those, 18 were treated using approaches other than burring because they did not meet the defined indications, and an additional five patients were lost to followup before 2 years, leaving 31 patients for analysis, all of whom were followed up for at least 2 years (mean, 7 years; range, 2-18 years).
Results: Of these 31 patients, one had a recurrence (3.2%). Complications using this approach occurred in three patients (9.7%), and included growth plate deformity (1) and genu varus (2) secondary to collapse of the reconstructed condyle. With only one recurrence, we cannot answer what the risk factors might be for recurrence; however, the one patient with recurrence presented with a large lesion and a pathologic fracture.
Conclusions: Curettage, burring, and bone grafting compare favorably in the literature with other approaches for aneurysmal bone cysts, such as cryotherapy and argon-beam coagulation. We conclude that high-speed burring alone as an adjuvant to intralesional curettage is a reasonable approach to achieving a low recurrence rate for aneurysmal bone cysts.
Level of Evidence: Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.