Spinal Osteoid Osteoma Revealed by Radiculopathy: Case Report and Literature Review.

Osteoid osteoma (OO) is a benign tumor that usually occurs in long bones of young males. We report a rare case of spinal OO in a 25-year-old woman, revealed by a sciatica. Spinal radiographs and computed tomography scan were normal, although performed at 6 months of symptom evolution. On magnetic resonance imaging, however, an important edema of the right transverse process of L5 vertebrae was depicted but was inconclusive. The diagnosis of OO was finally retained on a second computed tomography scan with thinner slices focused on the edematous area. The patient had an en-bloc excision of the tumor with complete regression of symptoms. Due to the atypical clinical presentation and the absence of common findings in imaging, the diagnosis was delayed by 12 months. Radiculopathy caused by spinal OO is a rare condition with no more than 30 cases reported in the literature. In fact, spinal OO usually presents with inflammatory back pain or painful scoliosis. This case emphasizes the importance of early suspicion and diagnostic interventions in the detection and treatment of OO.