Comparison of the results in patients operated upon for ruptured lumbar discs with and without spinal fusion.

A comparative study of 259 patients operated on for ruptured lumbar discs, with and without spinal fusion, has been carried out. Simple removal of the herniated nucleus pulposus was performed in 119 patients while 68 were subjected to combined removal of the herniated disc material and lumbo-sacral fusion. During the first postoperative months the results were similar in the two groups, with a satisfactory result in 89 and 88 per cent of the cases respectively. During the following years a significant difference occurred between the groups. Severe pain recurred in 27% of the patients with simple removal of the herniated disc material and in 15% of those with the combined operation (P less than 0.01). The cause of the recurrence in the patients without fusion was disc herniation in 10% (at the same level in 7% and at a different level in 3%), and adhesions, or osteochondrosis with or without instability in 17%. In the patients with the combined operation the recurrences were caused by pseudoarthrosis in 9%, by disc herniation in 3%, and by other causes in 3%. At the final examination 6--7 years after the first operation, the results were still better in the fused patients, but the difference was no longer significant. Eighty-five per cent of the patients with the combined operation has a satisfactory result with regard to pain as compared with 76% in the other group. Thus, the results show that the combined operation gives better protection against recurrence of pain. However, it is a more extensive procedure and has complications of its own, and it should therefore mainly be used in young patients.