Study Design. Prospective subcohort study.
Objective. To determine whether preoperative presence of degenerative spondylolisthesis worsens the outcome of patients undergoing unilateral laminotomy with bilateral decompression for lumbar stenosis.
Summary of Background Data. The standard surgical treatment for degenerative spondylolisthesis with lumbar stenosis is lumbar fusion after standard laminectomy. Although this strategy is widely adopted, it is not supported by class I evidence. This strategy assumes that degenerative spondylolisthesis worsens the outcome of laminectomy by causing postoperative instability. However, instability may be reduced or prevented by the use of less invasive decompression techniques.
Methods. To test the hypothesis that preoperative degenerative spondylolisthesis worsens the outcome of less invasive lumbar decompression, we performed a prospective cohort study of 165 consecutive patients who underwent unilateral laminotomy with bilateral decompression at our institution. The patients were prospectively followed with a standardized questionnaire, 36-Item Short Form Health Survey, and standing lumbar radiographs for a maximum follow-up period of 5 years. According to the presence or absence of degenerative spondylolisthesis, the patients were divided into 2 groups: an olisthesis group and a nonolisthesis group.
Results. The average 36-Item Short Form Health Survey physical score and bodily pain score improved substantially immediately after surgery. This improvement was maintained up to 5 years postoperatively. Progression of slippage was uncommon in both groups, with an overall incidence of 8% at 5 years of follow-up. There was no significant difference in the average physical score, the bodily pain score, or the rate of progression of slippage between the olisthesis and nonolisthesis groups.
Conclusion. Our study thus indicates that preoperative degenerative spondylolisthesis does not worsen the outcome of patients with lumbar stenosis undergoing unilateral laminotomy with bilateral decompression. These results suggest that lumbar fusion is often unnecessary in patients with degenerative spondylolisthesis and lumbar stenosis if the posterior decompression technique is unilateral laminotomy with bilateral decompression.
Level of Evidence: 2
This prospective subcohort study examined how degenerative spondylolisthesis affects the outcome of patients undergoing unilateral laminotomy with bilateral decompression for lumbar stenosis. The outcome was virtually the same between those patients with and without spondylolisthesis. These results may suggest that lumbar fusion is rarely needed for degenerative spondylolisthesis.
From the Department of Neurosurgery, Saitama Medical Center, Saitama Medical University, Kawagoe, Saitama, Japan.
Address correspondence and reprint requests to Han Soo Chang, MD, Department of Neurosurgery, Saitama Medical Center, Saitama Medical University, 1981 Tsujimichi, Kamoda, Kawagoe, Saitama, Japan 350-8550; E-mail: firstname.lastname@example.org
Acknowledgment date: August 6, 2013. First revision date: November 8, 2013. Second revision date: November 25, 2013. Acceptance date: November 26, 2013.
The manuscript submitted does not contain information about medical device(s)/drug(s).
No funds were received in support of this work.
No relevant financial activities outside the submitted work.