Osteoid osteoma: A masquerader of persistent knee pain in the setting of prior lateral tibial plateau cement subchondroplasty

Osteoid Osteoma (OO) is a common primary bone tumor that often presents with night pain in younger orthopedic patients. Although typically extra-articular, intra-articular presentations may be difficult to diagnose. While magnetic resonance imaging (MRI) provides excellent detailed imaging of the articular surface, it has been reported to lead to occasional misdiagnosis given limitations in spatial resolution, particularly for smaller lesions. Computed tomography (CT) remains the gold standard imaging modality for OO. The treatment for osteoid osteoma consists of medical management, minimally invasive image guided techniques, and surgical resection in order of most conservative to most aggressive. We present the case of a 31-year-old male with persistent posterolateral knee pain after subchondroplasty. CT demonstrated an OO in the posterior tibial plateau. The patient was successfully treated with CT-guided percutaneous radiofrequency ablation with complete resolution of symptoms. We also provide a brief literature review of the diagnosis and treatment of OO to help heighten the awareness of this sometimes inconspicuous diagnosis.