A Bicentric Propensity Score Matched Study Comparing Percutaneous Computed Tomography–Guided Radiofrequency Ablation to Magnetic Resonance–Guided Focused Ultrasound for the Treatment of Osteoid Osteoma

Purpose: To assess the safety and efficacy of computed tomography-guided radiofrequency (RF) ablation and magnetic resonance-guided focused ultrasound (MRgFUS) in the treatment of osteoid osteoma with a long-term follow-up study. Materials and Methods: Database research was performed at 2 different centers with experience in musculoskeletal interventions. Both centers, one performing RF ablation and the other MRgFUS, identified 116 patients who underwent either RF ablation or MRgFUS procedures for the treatment of symptomatic osteoid osteoma and retrospectively evaluated data regarding pain scores using a visual analog scale (VAS). Complications were recorded according to the Cardiovascular and Interventional Radiological Society of Europe classification system. Propensity score matching for multiple variables was performed. Pain scores before and after therapy were compared. Results: Of 116 patients treated, 61 and 55 underwent RF ablation and MRgFUS, respectively. Before treatment, the mean reported pain in the 2 groups were 9.1 +/- 0.88 (RF ablation) and 8.7 +/- 0.73 (MRgFUS) VAS units. After treatment, a statistically significant (P <.00001) overall reduction in pain symptomatology was recorded. No statistically significant difference was observed between the mean values of pain after treatment in both groups (P = .256). Over a mean of >2 years of follow-up, 4 cases of relapse (RF ablation, 1; MRgFUS, 3) and 1 complication (RF ablation) were observed. The analysis from propensity score matching that identified a matched cohort of 48 patients showed similar results. Conclusions: The 2 techniques for the treatment of osteoid osteoma resulted in profound and similar pain relief. The presence of thick cortical bone over the nidus can reduce the effectiveness of MRgFUS.