The spontaneous spinal epidural hematoma. A study of the etiology.

From the literature 199 cases of spontaneous spinal epidural hematoma (SSEH) are analyzed. With these data and the vascular anatomical characteristics of the spinal epidural space, the theories on the etiology of the SSEH are discussed. There seems to be no relationship between the SSEH and arterial hypertension. The age highly affects the level-distribution of the SSEH. The authors have the opinion that the posterior internal vertebral venous plexus plays an important part in the etiology of the SSEH. In the literature the role of a vascular anomaly in the etiology of the SSEH is overestimated. The cluster-type dural artery can easily be mistaken for a vascular anomaly.