Effects of surgery on cervical spondylotic myelopathy.

The results of surgery for treatment of cervical spondylotic myelopathy (CSM) were assessed 3 months (early results) and 2-8 years (late results) postoperatively in 99 patients. Extensive laminectomy as well as anterior decompression and fusion, or the two procedures at staged intervals, were used. Immediate postoperative deterioration was never seen after laminectomy performed under local anaesthesia (84 patients), while transient deterioration occurred after anterior surgery in 2 of 28 patients. Cervical spondylotic radiculopathy (CSR) was found in 73% of the patients. Operative treatment for CSM also improved root symptoms, anterior surgery to a larger extent than posterior decompression. Only 10% of the patients treated with extensive laminectomy needed a second anterior operation for radiculopathy. The progression of myelopathy was arrested in 95% of the patients after surgery. Improvement was obtained in 80% both in the early and late follow-up review when compared to the preoperative functional status. The evaluation disclosed a tendency of rapid improvement during the first 3 months, subsequently followed by slow improvement in 50% and slight deterioration in 15% of the patients. The degree of improvement was in many patients not sufficient to raise the functional capability to a higher level in the employed grading system. In our opinion it is therefore important to operate patients with CSM as early as possible before neurological deficits are too pronounced.