(Kiosk 2) Concurrent Osteoid Osteoma and Spondylolysis in a Young Man with Thigh Pain

Case Diagnosis: An adolescent male presenting with 4 months of thigh and back pain found to have both a spondylolysis and osteoid osteoma of his femur.

Case Description or Program Description: A 17 year old male presents to clinic with back pain and right leg pain for 4 months that started after a summer of football and construction work. He describes severe pain primarily in his right thigh that is constant but most bothersome at night. He also has back pain that is worse with activity and extension movements. Exam is significant for midline spine tenderness at L5 and pain with lumbar extension. He has pain with resisted right hip flexion but strength and reflexes are normal bilaterally.

Setting: Academic medical center

Assessment/Results: Workup is significant for a spondylolysis at L5-S1 without evidence of foraminal narrowing on MRI. Radiographs of the hips revealed a possible osteoid osteoma in the right femur that was followed by a CT scan confirming the diagnosis. Given his predominant thigh pain that was persistent at rest and the significant amount of reactive bone formation on imaging, we suspect his primary pain generator was the osteoid osteoma. It was recommended he rest from sports and work for 6 weeks and continue judicious use of anti-inflammatories. He was referred to orthopedics for consideration of radiofrequency ablation or resection of the osteoma.

Discussion (relevance): This case highlights the potential for multiple independent problems contributing to a patient’s presentation. Osteoid osteomas are rare, benign bone tumors that are most common in long bones and are most prevalent in adolescent or young adult males. They will often spontaneously resolve over multiple years but can also be treated with radiofrequency ablation or surgery.

Conclusions: Osteiod osteomas are rare bone tumors that should be considered in young patients with limb pain that persists at rest. It is important to keep a wide differential and consider multiple diagnoses if the patient presentation is unclear.