Spontaneous spinal cord herniation: case report and review of the literature.

OBJECTIVE AND IMPORTANCE Spontaneous herniation of the spinal cord substance through a previously uninjured and/or untouched dura is a very exceptional occurrence. Spontaneous spinal cord herniation, which was first reported 25 years ago, is a cause of myelopathy that is treatable but difficult to diagnose. CLINICAL PRESENTATION A 49-year-old female patient who presented with a 3-year history of a burning sensation and hyperesthesia in her right leg and a 3-month history of left leg stiffness was diagnosed as exhibiting signs of Brown-Séquard syndrome. Magnetic resonance imaging of the thoracic spinal canal demonstrated S-shaped anterior kinking and transdural herniation of the spinal cord at the T3-T4 levels. INTERVENTION The patient underwent surgery via a three-level laminectomy. The herniated part of the spinal cord was microsurgically reduced, and the dural defect was repaired with Gore-Tex membrane (WL Gore & Associates, Flagstaff, AZ). The outcome of surgery was excellent. CONCLUSION Review of the world literature revealed 29 reported cases, with 27 of these cases being published since 1990. The clinical features, radiological diagnosis, and treatment options for this unique entity are summarized, with a synopsis of numerous misconceptions that appeared in the literature. With more familiarity with and increased awareness of this entity, more cases will be diagnosed.