Anterior thoracic transdural spinal cord herniation:a sporadic, treatable cause of progressive myelopathy

Anterior thoracic transdural spinal cord herniation (ATTSCH) is a rare cause of slowly progressing thoracic myelopathy. The myelopathy is caused by herniation and subsequent trapping of the thoracic spinal cord through a defect in the anterior dural sac. We describe the case of a man, 38 years of age, who presented with a 4-year history of progressive pyramidal syndrome with sphincteral and erection disorders caused by ATTSCH. The patient underwent a surgical intradural exploration and release (detethering) of the spinal cord and reduction of the cord herniation; a polytetrafluoroethylene sleeve was inserted to cover the defect and to prevent the cord from reherniation. Anterior thoracic transdural spinal cord herniation is a treatable cause of myelopathy and early detection is of great importance to the prognosis. Because this condition is so rare and therefore, relatively unknown, delay in the diagnostic process and subsequent surgical treatment often occur.