Abstract
We reviewed 20 cases of lumbar canal stenosis that required reoperation in our hospital during the past 12 years. There were 11 men and 9 women whose ages ranged from 43 to 76 years at the time of the first decompression surgery (average, 60.9). Secondary surgery had been performed on an average 3 years 2 months after first decompression (range, from 4 months to 13 years). The stenoses had been classified as degenerative stenosis, degenerative spondylo-listhesis or post-operative stenosis. Initially, fenestration had been performed in 9 patients and laminectomy in 11 patients. Laminectomy (with or without diskectomy) was performed as the secondary surgery in all patients. The causes of recurrence were recurrent stenosis (n=9), insufficient decompression (n=5), stenosis at other vertebral levels or on the opposit side at the same level (n=3) and lumbar disc herniation at the laminectomy site (n=3). Of the 9 patients with recurrent stenosis, 7 patients showed bone regrowth at the site of decompression. Bone regrowth of the laminal arch may cause recurrent stenosis.
