Idiopathic spinal cord herniation (ISCH) is a rare, although increasingly recognized, cause of myelopathy. It is the result of an anterior dural defect in the thoracic spine through which the spinal cord herniates. Surgical restoration of the herniated cord to its normal position is usually followed by significant improvement in patients' clinical status. Differing surgical techniques have been used to manage the dural defect. In this report the authors discuss the cases of five patients (four women and one man) with ISCH treated during a 13-year period. Clinical and imaging findings in each patient are reported. Two different surgical techniques were used to treat this condition: dural defect enlargement in two cases and dural patch secured with stitches in three. The intra- and postoperative findings are discussed in relation to the two surgical techniques. Based on the results and complications in these five cases, the authors now believe that ISCH should be treated, when feasible, by using a dural patch to close the dural defect at the site of the herniation.