2003 Volume 9 Issue 1 Pages 80-88
Based on about twenty thousand cases of epidural blook to lumbar herniation, I present techniques for a safer and more useful and rapid method for epidural block . The difficulty of epidural blook is dependent on the thickness of the ligamentum flavum or the shape of posterior wall of the vertebral foramen. For 101 examples of lateral x-ray of bleached spinal bones, ①I classified the shape of posterior wall of the vertebral foramen into four types. ②and I represented the thickness of the lamina by means of the interval between the anterior surface of the lamina and the posterior surface of the pars interarticularis. I named this interval the S-zone (stenosis zone). There are three types of S-zone, +, 0 and - . This analysis of S-zone is useful in predicting the thickness of the ligamentum flavum and the a-p diameter of the foramen by the lateral radiograph of the lumbar spine.