Modern concepts of primary aneurysmal bone cyst

Area of Science:

• Orthopedics
• Oncology
• Radiology

Background:

• Aneurysmal bone cysts (ABC) pathogenesis remains unclear, with theories including reactive vascular malformations or genetic bone tumors.
• Recent genetic and immunohistochemical studies suggest primary ABC is a tumor, not a reactive lesion.
• Chromosomal analyses and familial cases indicate a potential hereditary factor in ABC pathogenesis.

Purpose of the Study:

• To review the current understanding of aneurysmal bone cyst (ABC) etiology and treatment options.
• To highlight diagnostic challenges and differentiate ABC from unicameral bone cysts (UBC).
• To discuss various therapeutic approaches and their efficacy.

Main Methods:

• Review of existing literature on ABC diagnosis and treatment.
• Analysis of imaging characteristics (CT, MRI) for differentiating ABC from UBC.
• Evaluation of treatment modalities including curettage, resection, injections, and embolization.

Main Results:

• Imaging studies like CT and MRI may not provide definitive ABC diagnosis.
• Diagnostic criteria such as double density fluid level, septation, and specific MRI signals suggest ABC over UBC.
• Treatment outcomes vary, with biopsy being crucial before any intervention.

Conclusions:

• Optimal treatment for ABC remains debated, with options including curettage, resection, and embolization.
• Ethibloc treatment is controversial; some recommend it as a first-line therapy for non-spinal lesions.
• Minimally invasive techniques using demineralized bone and bone marrow may promote self-healing in primary ABC.