Long-term evaluation of decompressive surgery for degenerative lumbar stenosis.

One-hundred patients who had undergone decompressive surgery for lumbar stenosis between 1980 and 1985 were evaluated as to their long-term outcome. Four patients with postfusion stenosis were included. A 5-year follow-up period was achieved in 88 patients. The mean age was 67 years, and 80% were over 60 years of age. There was a high incidence of coexisting medical diseases, but the principal disability was lumbar stenosis with neurological involvement. Results were categorized as either a surgical success or a failure, depending upon the achievement of preset goals within the context of lifestyle and needs. There were no perioperative complications. Initially there was a high incidence of success, but recurrence of neurological involvement and persistence of low-back pain led to an increasing number of failures. By 5 years this number had reached 27% of the available population pool, suggesting that the failure rate could reach 50% within the projected life expectancies of most patients. Of the 26 failures, 16 were secondary to renewed neurological involvement, which occurred at new levels of stenosis in eight and recurrence of stenosis at operative levels in eight. Reoperation was successful in 12 of these 16 patients, but two required a third operation. The incidence of spondylolisthesis at 5 years was higher in the surgical failures (12 of 26 patients) than in the surgical successes (16 of 64). Spondylolisthetic stenosis tended to recur within a few years following decompression. To forestall recurrences, it is suggested that stabilization be carried out at levels of spondylolisthetic stenosis and the initial decompression include adjacent levels of threatening symptomatic stenosis. However, the heterogenicity of this patient population, with varying patterns and levels of symptomatic stenosis, precludes application of rigid surgical protocols.