Dural Tears in Adult Deformity Surgery: Incidence, Risk Factors, and Outcomes

Study Design: Retrospective cohort study. Objectives: Describe the rate of dural tears (DTs) in adult spinal deformity (ASD) surgery. Describe the risk factors for DT and the impact of this complication on clinical outcomes. Methods: Patients with ASD undergoing surgery between 2008 and 2014 were separated into DT and non-DT cohorts; demographics, operative details, radiographic, and clinical outcomes were compared. Statistical analysis included t tests or χ² tests as appropriate and a multivariate analysis. Results: A total of 564 patients were identified. The rate of DT was 10.8% (n = 61). Patients with DT were older (61.1 vs 56.5 years, P =.005) and were more likely to have had prior spine surgery (odds ratio [OR] = 2.0, 95% confidence interval [CI] = 1.2-3.3, P =.007). DT patients had higher pelvic tilt, lower lumbar lordosis, and greater pelvic-incidence lumbar lordosis mismatch than non-DT patients (P <.05). DT patients had longer operative times (424 vs 375 minutes, P =.008), were more likely to undergo interbody fusions (OR = 2.0, 95% CI = 1.1-3.6, P =.021), osteotomies (OR = 2.2, 95% CI = 1.1-4.0, P =.012), and decompressions (OR = 2.3, 95% CI = 1.3-4.3, P =.003). In our multivariate analysis, only decompressions were associated with an increased risk of DT (OR = 3.2, 95% CI = 1.4-7.6, P =.006). There were no significant differences in patient outcomes at 2 years. Conclusions: The rate of DT was 10.8% in an ASD cohort. This is similar to rates of DT reported following surgery for degenerative pathology. A history of prior spine surgery, decompression, interbody fusion, and osteotomies are all associated with an increased risk of DT, but decompression is the only independent risk factor for DT.