Balloon-assisted osteoplasty of periacetabular tumors following percutaneous cryoablation.

PURPOSE: To describe the feasibility, safety, and effectiveness of a technique using vertebral augmentation balloons to promote delivery of cement into periacetabular tumors after cryoablation for fracture prevention.

MATERIALS AND METHODS: A retrospective review was performed of seven consecutive patients (six men and one woman; mean age, 64 y ± 8) with unilateral periacetabular tumors (mean size, 4.2 cm ± 1.4) treated with cryoablation and balloon-assisted osteoplasty for fracture prevention. Cortical defects were seen in six (86%) tumors, and additional pathologic fractures occurred in five (71%) tumors before treatment. The cohort included six (86%) Harrington class I defects and one (14%) class II defect. Procedures were performed with computed tomography fluoroscopic guidance and general anesthesia. Vertebral augmentation balloons (mean, 2; range, 1-4) were inflated within the ablation cavity immediately before or during cement injection.

RESULTS: All procedures were technically successful. Median percentage tumor fill was 63% (range, 17%-96%). Minor cement leakage occurred in two (29%) patients with no symptomatic or intraarticular extravasation. A new nondisplaced fracture occurred in one patient and was conservatively managed. No major complications occurred. Local tumor progression occurred in one (20%) of five patients with imaging follow-up.

CONCLUSIONS: Balloon-assisted osteoplasty after cryoablation of periacetabular tumors appears feasible, safe, and effective for fracture prevention. This technique directs cement instillation into ablation defects with a high degree of filling and minimal leakage.