Cervical spondylotic myelopathy treated by single-stage multilevel anterior decompression. A prospective study.

Fifty patients suffering from advanced cervical spondylotic myelopathy were surgically treated to eliminate compression of the cord. All disc protrusions demonstrated by positive-contrast myelography that measured larger than 1.5 mm were excised. Each patient was operated on in a single-stage procedure by anterior discectomy, without bone fusion, for protrusions between 2 and 4 mm, and by vertebral trephination and intercorporeal iliac bone-graft fusion for protrusions larger than 4 mm. There were no serious complications. Improvement by one clear disability grade (as defined by the authors) was observed in 36% of the cases, by two grades in 56%, and by three grades in 8%. No patient showed an improvement of four grades. During a follow-up period varying from 2 to 5 years, none of the patients showed clinical evidence of progression of myelopathy; however, 44% of patients showed definite radiological evidence of progression of cervical spondylosis. This indicates that myelopathy may be arrested and may regress, but the process of cervical spondylosis continues unabated in almost half of the cases.