Comparative retrospective study of patients operated for cervical disc herniation and spondylosis.

173 patients suffering from symptoms of cervical disc herniation or spondylosis were surgically treated during 1975 through 1984 by Cloward's method via the anterior route or by total or hemilaminectomy with Epstein's foraminotomy via the posterior route. Of the 41 patients with disc herniation, 37 had radiculopathy as the main disorder and only 4 myelopathy. Of the 132 spondylosis cases radiculopathy was the main disorder in 92 and myelopathy in 40 cases. The operative route was selected according to the site of the osteophytes or disc herniation. The criteria for operative treatment were persistent radicular pain, motor weakness and progressive muscle atrophy, or evidence of cord compression. All patients underwent myelography preoperatively and sometimes also x-ray computed tomography. A clear correlation between the roentgenographic findings, clinical signs and symptoms served as the prerequisite for operative treatment. Follow-up review an average of 55 months after the operation showed excellent or good results in 80% of the disc herniation cases, but in only 35% of those with spondylosis. However, in the latter group pain relief was obtained in 76% of cases. In the spondylosis series there were significant correlations between the parameters of severity of disease and duration of symptoms and the surgical results, whereas in the disc herniation series no clear correlations were observed. Gait disturbances associated with myelopathy were only minimally relieved. There was no clear correlation after surgery between the degree of the disease and working capacity, but the duration of preoperative disability was significant in this respect. Postoperative complications were infrequent and no severe complications occurred.