Treatment of Aneurysmal Bone Cysts by Minimally Invasive Curettage and Allogenic Bone Impaction Grafting: Mid-to Long-term Results.

Objective: Recurrence is the main hinderance in treatment of aneurysmal bone cysts (ABCs). Therefore, several treatment modalities and adjuvant therapies have been proposed. In this study, we aim to evaluate the long-term effectiveness of percutaneous curettage and allogenic bone grafting as a new, minimally invasive modality in treating ABCs.

Methods: We performed a retrospective review of the medical records of patients diagnosed with primary ABCs at a university hospital over a 10-year period (2000-2010). We selected all patients who were diagnosed with primary ABC in the extremities and pelvis, treated with the same surgical procedure, and were followed for at least 2 years postoperatively. All patients underwent the same procedure of percutaneous curettage and impaction of allogenic pulverized fine bone fragments (harvested from locally stored femoral heads) mixed with autologous bone marrow aspirate from the iliac bone. We reported patient's characteristics (age and gender), site and size of the lesion, presenting symptoms, Capanna classification, follow-up duration, and post-operative complications. Assessment of cyst healing was based on the appearance on radiographs according to the modified Neer classification.

Results: Nineteen patients were included in this study; 10 patients were males and nine were females. The mean age was 9.6 years (range 3-15). The location of the lesions was as follows: femur (eight), tibia (four), pelvis (four), proximal humerus (one), distal radius (one), and calcaneus (one). The most common presenting symptom was pain in the involved area. Pathological fracture was the presenting feature in two patients. The mean follow-up duration was 6.4 years (range 2-18). The earliest radiological sign of incorporation of the allograft was seen at 3 months after surgery. All patients showed bone remodeling and radiographic resolution (classified as either A or B on the modified Neer classification) of their cystic lesions within 6 months. No local recurrence, infection, or pathological fractures occurred during the follow-up period.

Conclusion: Percutaneous curettage and impaction of allogenic bone graft mixed with autogenic bone marrow aspirate is an efficient, minimally invasive, reproducible, and affordable procedure for the treatment of primary ABCs.