Establishment of Service of Ablation of the Osteoid Osteoma: What we Learned During the last 4 Years

Introduction: Osteoid osteoma (OO) is a benign bone lesion that causes significant disability. Radiofrequency ablation (RFA) under CT guidance became standard treatment in the last decade. In this study we analyzed our experience with RF ablation during the last 4 years.

Methods: Fifty-seven patients were the subjects of this study. There were 38 males and 19 females, with mean age of 16.2 (3-54). Mean time from start of symptoms to RFA was 11 months. Most common location of OO was femoral shaft (19); tibia (15); femoral neck (12); acetabulum (3); talus (3), other bones (5). 36 cases of right side pathology vs. only 21 cases of left side. All patients underwent RFA (Covidien, Medtronic) under CT guidance and general anesthesia.

Results: Cure was achieved in 55 patients. After initial improvement, two patients experienced a return of night pain and RFA was performed again. (In both these patients, RFA was initially not done in the center of the nidus). In two patients with OO at the midshaft of the tibia, RFA failed and mechanical ablation was done using repetitive mechanical drilling of the nidus. In one patient with nidus in the acetabulum, local AVN of the femoral head appeared after ablation. One patient with OO of the midshaft of the femur broke the femur 10 months after the procedure after minor trauma.

Conclusion: Establishment of the RFA service of the OO is not an easy task. Despite many pitfalls, the majority of patients experienced cure with an excellent outcome.