Thoracic myelopathy due to idiopathic epidural ossifications in a child: a case report.

Study Design. A rare case of thoracic myelopathy due to epidural ossification in a child. Objective. To determine a differential diagnosis of thoracic myelopathy. Summary of Background Data. Ectopic ossification is one of the common lesions that can cause thoracic myelopathy. The majority of the cases occur in adults and ossification usually occurs in ligamentous tissues. To the authors' knowledge, no published reports in the English literature have described a case of thoracic myelopathy in a child caused by ectopic epidural and nonligamentous ossification. Methods. A 15 year-old girl presented with a chief complaint of bilateral numbness of the thigh and gait disturbance. Results. Computed tomography demonstrated 3 islands of epidural ossifications that surrounded the dural sac from T2-T4 and compressed the spinal cord. These lesions, which were not due to ossification of the ligament, were surgically resected. After resection, her symptoms completely disappeared. Histologic diagnosis of the removed specimen was fibro-osseous tissue. Radiologic examination demonstrated no recurrence of the lesion 6 years after surgery. Conclusion. We describe this condition as idiopathic epidural ossification, as the reason is unknown and discussed its etiology.