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The Long-Term Reoperation Rate Following Surgery for Lumbar Stenosis: A Nationwide Sample Cohort Study with a 10-Year Follow-Up.

STUDY DESIGN
Retrospective cohort study of a nationwide sample database.


OBJECTIVE
The objective of the present study was to compare the long-term incidence of reoperation for lumbar spinal stenosis (LSS) after anterior fusion, posterior fusion, and decompression.


SUMMARY OF BACKGROUND DATA
Surgical treatment for LSS can be largely divided into two categories: decompression only and decompression with fusion. A previous nationwide study reported that fusion surgery was performed in 10% of patients with LSS, and the 10-year reoperation rate was approximately 17%. However, with the development of surgical techniques and changes in surgical trends, these results should be reassessed.


METHODS
The National Health Insurance Service-National Sample Cohort of the Republic of Korea was utilized to establish a cohort of adult patients (N = 1,400) who first underwent surgery for LSS during 2005-2007. Patients were followed for 8-10 years. Considering death before reoperation as a competing event, reoperation hazards were compared among surgical techniques using a Fine and Gray regression model after adjustment for sex, age, diabetes, osteoporosis, Charlson comorbidity index, severity of disability, type of medical coverage, and type of hospital.


RESULTS
The overall cumulative incidence of reoperation was 6.2% at 2 years, 10.8% at 5 years and 18.4% at 10 years. The cumulative incidence of reoperation was 20.6%, 12.6% and 18.6% after anterior fusion, posterior fusion, and decompression, respectively, at 10 years postoperatively (p = 0.44). The first surgical technique did not affect the reoperation type (p = 0.27). Decompression was selected as the surgical technique for reoperation in 83.5% of patients after decompression, in 72.7% of patients after anterior fusion, and in 64.3% of patients after posterior fusion.


CONCLUSION
The initial surgical technique did not affect reoperation during the 10-year follow-up period. Decompression was the most commonly used technique for reoperation.


LEVEL OF EVIDENCE
4.