Computed tomography guided radio-frequency ablation of osteoid osteomas in atypical locations

PURPOSE: Percutaneous radio-frequency ablation is a minimally invasive treatment option for osteoid osteomas. The ablation process is straightforward in the more common locations like the femur/tibia. Surgery has historically been the gold standard, but is currently used in lesions, that may not be effectively and safely ablated, i.e. close to skin/nerve. Radio-frequency ablation can still be used in such cases along with additional techniques/strategies to protect the sensitive structures and hence improve the outcomes. The authors describe their experience with four challenging osteoid osteoma ablation cases. METHODS: We retrospectively reviewed radio-frequency ablations of four osteoid osteomas in rather atypical locations, the protective techniques/strategies employed, the adequacy and safety of the radio-frequency ablation with the use of these techniques. RESULTS: All patients had complete resolution of pain with no recurrence in the follow-up period. No complications were reported. CONCLUSION: RFA has been proven to be an effective and safe option for treatment of OOs in the common locations. It is generally recommended to have a 1 cm safety margin between the RF probe and any critical structures in the vicinity. However, with OOs in atypical locations this may not be always possible and hence additional techniques may be needed to ensure protection of the surrounding sensitive structures and also allow for effective ablation.