The efficacy of computed tomography-guided percutaneous microwave ablation in patients with osteoid osteoma according to nidus location in long bones: A single-centre initial experience

Abstract

This study aims to assess the efficacy of microwave ablation (MWA) treatment in painful extra-articular osteoid osteoma (OO) in long bones in a consecutive series of patients and to compare the technical and clinical success in terms of pain scores according to their location. A total of 23 patients who were diagnosed with OO in long bones and treated with MWA between January 1, 2016, and June 1, 2020 were enrolled in this study. Medical data and images were reviewed for age, gender, size of the nidus and duration of pain. Patients were then categorized into three groups according to the location of nidus (pertrochanteric, metaphyseal or diaphyseal). Operation length and technical and clinical success rates were compared. Technical success was achieved in 100% of patients. Primary clinical success following MWA was 82.6%. The most common location was the pertrochanteric region (34.8%). In comparing the pain scores with the locations of the lesions, no statistically significant difference was found between the first-day (p = 0.504) and first-week (p = 0.648). However, significant difference was present between the first month (p = 0.016), third month (p < 0.001) and sixth month (p = 0.001). The statistically significant differences between the sites were due to the difference between the pertrochanteric and diaphyseal lesions. CT-guided percutaneous MWA is safe and effective in the treatment of OO located in long bones without any recurrence. However, management of pertrochanteric OOs requires specific expertise and follow up. Further studies are expected in the future to assess the long-term efficacy and safety of MWA for the treatment of OO, especially for cases in pertrochanteric locations of the femur, which have an increased risk of local recurrence.