Surgical treatment of idiopathic transdural spinal cord herniation: a new technique to untether the spinal cord.

Idiopathic transdural spinal cord herniation is a rare but treatable cause of thoracic myelopathy caused by herniation of the spinal cord through a defect in the dura. The diagnosis is frequently missed or delayed, but the latest imaging techniques can document spinal cord herniation through a dural defect. Surgical treatment, consisting of reducing the herniation by closing the dural defect or widening the aperture to prevent spinal cord compression, is rather successful. We describe a new technique to untether the spinal cord by wrapping a dura graft around the myelum to prevent recurrent transdural herniation. Two patients and a review of the literature are discussed. We conclude that high-resolution T2 magnetic resonance imaging is the best imaging modality to detect the entity, and wrapping the myelum is an effective surgical technique to untether the spinal cord.