Is radiofrequency ablation safe and effective in treating osteoid osteomas? A prospective single-center study with atypical cases.

PURPOSE: Osteoid osteomas are benign and nonprogressive lesions. The clinical presentation of osteoid osteoma is typical with night pain responsive to nonsteroidal anti-inflammatory agents. The typical radiological appearance is lucent nidus and adjacent reactive sclerosis. The most traditional management of osteoid osteoma is surgical removal which is associated with significant morbidity. This article aims to demonstrate our single-center experience of 55 patients with osteoid osteoma treated with percutaneous radiofrequency ablation (RFA). METHODS: Fifty-five symptomatic patients who were seen at our orthopedics outpatient clinics, diagnosed with osteoid osteoma, and referred to interventional radiology department between May 2015 and April 2019 were enrolled. The nidus size, pain numeric rating scale score, and intramedullary edema diameter before and after RFA were compared. Clinical and technical success, intervention-related complications, and need for subsequent ablation were recorded. RESULTS: Of the 55 patients, including 12 pediatric cases, 6 had atypical locations such as metatarsal, vertebra, and scapula, while 1 case had osteoid osteoma with multiple nidus. The mean age was 18.5 ± 9.6 years. Preintervention maximum nidus diameter, pain score, and edema diameter were significantly lower in postintervention measurements (p < 0.001). Technical success rate was 98.1%, and clinical success was 96.36%. Severe complication occurred in one patient with soft tissue burn and osteomyelitis. CONCLUSION: This is one of the largest series of osteoid osteoma treated with RFA done in a single center with atypical cases. In conclusion, RFA is safe and effective in both pediatric and adult patients with rare complications even in challenging cases with atypical locations.