Modern treatment of unicameral and aneurysmatic bone cysts.

The best treatment of unicameral bone cyst and aneurismatic bone cyst (ABC) is debated in the literature. For simple bone cysts, multiple treatments were proposed from observation only to open curettage. The historical treatment with intraosseous injection of methylprednisolone acetate into the bone cysts nowadays is reduced due to the morbidity of multiple injections and the risk of multiple pathologic fractures until the healing. Different types of treatments for ABC are reported, including surgery, percutaneous treatments, and medical treatments; however, there is currently no consensus on the best approach. The association of curettage, bone graft, and elastic stable intramedullary nail (ESIN) had a success rate of over 85%. Decompressing the cyst wall is more critical for increasing the healing rate than the type of graft used to fill the cavity. In ABC, sclerotherapy offers the advantages of lower invasiveness and morbidity, associated with better functional scores and faster return to full weight-bearing. Moreover, they can be used in challenging locations. Selective arterial embolization is a complex procedure and often requires association with other treatments. Further studies are needed to confirm the effectiveness of denosumab and its side effects on skeletally immature patients. Curettage with adjuvants and autogenous bone grafting still shows promising results and can be used in larger, aggressive defects or superficial lesions. For simple bone cysts, the combination of curettage, bone graft, and ESIN showed the best results. Sclerotherapy for ABC also shows promising results.