Long-term results of surgery in lumbar spinal stenosis.

In many studies the results of operative treatment of lumbar stenosis were analysed several years on average after surgery, but in only one (Verbiest 1977) were the result assessed at very long term. We report a long-term clinical and radiographic follow-up of patients treated surgically for central lumbar stenosis. The results of operation for central lumbar stenosis appear to deteriorate in the long-term in at lest one-third of patients. In most patients, the resected portion of the posterior arch regrows over the years following surgery. Long term clinical results are poor in those patients showing a moderate or marked bone regrowth. Of the patients with degenerative spondylolisthesis, those submitted to fusion show a higher proportion of satisfactory results in the long term. Total laminectomy exposes to no risk of vertebral instability when the operated motion segments are preoperatively stable; however, instability is easily produced or increased when potential or real instability is present preoperatively