CT-guided radiofrequency ablation of a tibial osteoid osteoma in pregnancy

Osteoid osteomas are painful benign bone tumors that primarily affect the long bones and may be managed conservatively with nonsteroidal anti-inflammatory drugs (NSAIDs). When surgical management is required, minimally invasive techniques such as image-guided radiofrequency ablation (RFA) are preferred. Management of osteoid osteomas during pregnancy poses a clinical challenge as NSAIDs are often contraindicated and there are limited reports describing surgical treatment in pregnancy. We present the case of a 32-year-old woman at 34 weeks' gestation who presented with severe right lower extremity pain exacerbated at night. CT imaging of the tibia revealed an 8 mm subperiosteal nidus with focal cortical thickening, periosteal bone formation, and a small central calcification consistent with an osteoid osteoma. The patient had minimal pain relief with acetaminophen and escalating opioid requirements and thus underwent an uncomplicated ultrasound and CT-guided RFA of the lesion with resolution of pain. The total CT dose length product was 81 mGy-cm, well within the acceptable radiation threshold of pregnancy, and minimized by use of ultrasound for localization and needle advancement. The patient subsequently had an uncomplicated term vaginal delivery. In pregnant patients for whom NSAIDs are not a viable treatment option for osteoid osteoma, this case demonstrates that image-guided RFA can be a safe and effective management strategy when performed by a multidisciplinary team comprising of musculoskeletal radiology, maternal-fetal medicine, and anesthesiology.