Abstract
Purpose: There are a wide variety of operative procedures for lumbar spinal canal stenosis. Bilateral fenestration, preserving the continuity of the lamina and spinous processes, has widely been employed in our department and its affiliated hospitals. The following questions are raised: Are decompressive effects of fenestration and spinal stability maintained without spinal fusion or instrumentation? In order to answer the questions, we compared the rates of revision after fenestration with those after laminectomy alone and decompressive surgery with spinal fusion.
Materials and methods: The registry of spinal surgeries of our university and affiliated hospitals from 1988 to 1997 was consulted.
During the first 5-years period 1159 patients underwent decompressive surgery. 908 of them had spondylosis and 251 had degenerative spondylolisthesis (DO) as a contributing factors of neural compression. Fenestration was done in 740 (81%) of patients with spondylosis and in 176 (70%) of patients with DO.
Results: Regarding the whole series 31 out of 1159 patients had a revision. The revision rate was 2.7%. 15 out of 908 patients (1.7%) with spondylosis and 16 out of 251 patients (6.4%) with DO underwent revisions. 11 out of 740 (1.5%) with spondylosis and 11 out of 176 (6.3%) with DO underwent revisions after fenestration. No significant differences were found among the revision rate of fenestration, laminectomy and decompressive surgery with spinal fusion.
Conclusion: The decompressive effect of fenestration was maintained long enough, even for degenerative spondylolisthesis. As a first operation spinal fusion is not necessarily indicated for lumbar canal stenosis.
The abstracts were prepared by Professor Jegan Krishnan. Correspondence should be addressed to him at the Flinders Medical Centre, Bedford Park 5047, Australia.
