Management of Asymptomatic Bilateral Iliac Crest Aneurysmal Bone Cysts

Initial Evaluation and Risk Stratification

The American College of Radiology recommends observation with periodic imaging surveillance as the initial approach for asymptomatic aneurysmal bone cysts (ABCs) discovered incidentally, reserving intervention for symptomatic lesions or those at high risk for pathological fracture 1
Dedicated radiographs of the affected area should be obtained to establish baseline characteristics and assess fracture risk, providing critical information about lesion margins, periosteal reaction, cortical thinning, size, and extent of bone involvement 1, 2, 3
The size of the lesion, location, degree of cortical thinning, and patient activity level are factors that contribute to the risk of pathological fracture, with large ABCs, pelvic/iliac crest lesions, and extensive cortical destruction increasing fracture risk 1

For asymptomatic ABCs without high fracture risk, surveillance imaging with baseline radiographs and follow-up radiographs at 3-6 month intervals initially, and extending to annual imaging if stable after 1-2 years, is recommended 1, 2, 3
Intervention becomes necessary when asymptomatic ABCs demonstrate progressive enlargement, significant cortical thinning, large size, or location in critical weight-bearing areas with structural compromise 1
Patients should be counseled to report new symptoms immediately, particularly pain, which may indicate lesion expansion or impending fracture 1

Surgical curettage with bone grafting is an option for lesions with impending or actual pathological fracture, failed minimally invasive treatments, or anatomically unsuitable lesions for percutaneous approaches 1