Radiofrequency ablation of intra-articular osteoid osteoma of the hip.

Diagnosis and treatment of intra-articular osteoid osteoma is challenging. We present 16 patients with intra-articular osteoid osteomas of the hip treated with percutaneous radiofrequency ablation. Eight osteoid osteomas were located in the femoral head, six in the femoral neck, and two in the acetabulum. Three of the 16 patients had had an incorrect previous diagnosis. Percutaneous radiofrequency ablation was a clinical and technical success in all 16 patients. Within the first 24 h after the procedure, pain improved in all patients. Five patients had pain relief within the first 3 days after the procedure, nine patients within the first week and two patients within 2 weeks. Residual or recurrent symptoms were not reported by the last follow-up. At the 12-month follow-up, computed tomography and magnetic resonance imaging showed complete ossification and bone regeneration at the site of the lesion in three patients, partial ossification in six patients and no changes in seven patients. Computed tomography-guided percutaneous radiofrequency ablation is a simple, minimally invasive, safe and effective method for the treatment of most intra-articular osteoid osteomas.