To assess rates and causes for reoperation following spine surgery for degenerative lumbar spondylolisthesis at early and midterm follow-up time points. Multicenter, prospectively collected data from the Canadian Spine Outcomes and Research Network (CSORN) DLS prospective study was analyzed to compare patient demographic, functional, clinical, and radiological outcomes as well as reoperation rates for decompression alone (DA) or decompression and fusion (D&F) in the treatment of single or two-level lumbar spondylolisthesis. Logistic regression models were used to analyze the effect of surgical procedure type on multiple characteristics. Univariate 2-tailed analyses were used to identify other outcome differences between D&F and DA. Kaplan-Meier unadjusted risk difference and cox adjusted absolute risk difference were calculated accounting for age, sex, grade of spondylolisthesis (Grade I vs Grade II and III), back pain at baseline, ODI score at baseline, and PI minus LL>10. There were 587 patients eligible for follow-up within the cohort (406 D&F and 181 DA). D&F patients were younger (65.0 ± 8.7 vs. 69.06 ± 10.1 years, p=0.001), more often female (64.5% vs. 53.0%, p=0.01), had a higher grade of spondylolisthesis (33% vs. 13.3%, p=0.001), and showed lower baseline functional status on the ODI score (45.7 ± 14.6 vs. 40.8 ± 14.5, p=0.001). D&F procedures had longer operating times (181.0 ± 52.4 vs. 88.1 ± 35.6 minutes, p=0.001) and hospital admissions (4.0 ± 2.4 vs. 1.5 ± 2.6 days, p=0.001) In total, 64 patients (10.9%) underwent reoperation surgery. Patients undergoing D&F had a higher reoperation rate (12.3%) compared to DA (7.7%). Reasons for reoperation differed by index surgery. 50% of revision surgery performed in DA was at the same level as the index operation, compared to only 2 of the 50 D&F patients requiring a revision decompression at the level of index surgery (p=0.001). Adjacent segment pathology was the most common reason for reoperation in D&F cases (48%), whereas it accounted for only 21.4% of reoperations in DA cases. In the reoperation group, irrigation and drainage were more common in fusion procedures than in decompression procedures (16% D&F versus 7.1% DA, p=0.670). The absolute adjusted risk difference for reoperation was higher for D&F at the 12-month – 60-month time points for follow-up. D&F patients experience higher overall reoperation rates at both early and late follow-up intervals, primarily due to a higher rate of early I&D compared to DA surgery. Our results were similar to previous studies that have shown higher early revision surgery rates for DA, and higher revision rates at adjacent levels at later time points in D&F. Therefore, reporting reoperation and revision data separately provides more precise information on each procedure's expected outcomes, including the resources required during the follow-up period.
Mishreky et al. (Wed,) studied this question.