Cervical spondylotic myelopathy: a cooperative study.

A series of 521 cases of CSM in 22 clinics in Spain and Portugal were studied. The severity of the clinical picture, both before and after the operations, was graded following a six point scale (a modification of Nurick's). The operations the patients underwent were classified into eight types and their results expressed by using the same scale. Some improvement has been attained in all grades of myelopathy with all types of operations, but better results, especially in advanced cases, have been obtained when surgical fixation of the spine, as well as laminectomy, has been carried out.