Surgical results of myelopathy secondary to the cervical disc herniation and the availability of CTD

This study evaluated the contribution of computed tomographic discography (CTD) to the surgical indications and selection of surgical techniques in cervical disc herniation. The study population consisted of 73 patients who were diagnosed as having cervical disc herniation by CTD: Of them, hernia mass was confirmed by surgery in 64 patients (a concordance rate of 88% between CTD and surgical findings). In evaluable 40 patients receiving computed tomographic myelography (CTM), the rate of flattened spinal cord on CTM was significantly correlatd with postoperative prognosis. Flattened spinal cord was favorably improved. Higher preoperative flat rate was associated with severer cervical disc herniation. CTD provided the information concerning the positional relation in the posterior longitudinal ligament of hernia mass. Preoperative severity, preoperative rate of flattened spinal cord, and the site of protrusion of hernia mass were independent of surgical outcome. (N.K.)