Introduction: Despite the many different approaches that exist for spinal fusion, few studies to date have directly measured outcome differences between these various techniques, and data comparing long-term outcomes such as reoperation rates and out-of-hospital complications are lacking.
Methods: We designed a retrospective, cohort analysis using the MarketScan database. Patients were included if they were 18 years of age or older and underwent a lumbar fusion surgery using either an anterior or posterior approach between the years 2000 and 2009. Patients were excluded if they received a circumferential fusion, or if they had less than one year of available preoperative follow-up or less than two years of available postoperative follow-up. Our outcomes of interest were reoperation rates, 90-day complication rates, and post-operative health resource utilization. Anterior and posterior surgery patients were compared in multivariate analysis using an inverse probability weighted propensity-score model controlling for patient demographics, comorbidities, number of levels fused, and underlying diagnosis.
Results: A total of 38,566 patients met our inclusion criteria, of which 33,715 (87.4%) had a posterior fusion and 4,848 (12.6%) underwent an anterior fusion. 3667 (9.5%) patients underwent a reoperation. In multivariate analysis, we found that those receiving an anterior fusion had a significantly higher two-year reoperation rate (OR 1.47, 95% CI: 1.30-1.65, p<0.0001), but at maximum follow-up, differences became non-significant (p=0.0524). The 90-day complication rate was 15.8%, with anterior surgery patients significantly more likely to experience more complications (RR: 1.60, 95%CI: 1.51-1.70, p<0.0001). Anterior fusion patients generally also had greater levels of post-operative health utilization, with an average of $7,580 more in total health care charges (95% CI: $6000-$9160, p<0.0001).
Conclusions: Anterior lumbar surgical approaches may be associated with higher post-operative morbidity and higher reoperation rates than posterior fusion approaches. More research is needed to establish the relative risks, benefits, and clinical evidence for different spinal fusion techniques.
Patient Care: This research will help surgeons in selecting optimal surgical approaches for patients with degenerative lumbar spine disease.
Learning Objectives: By the end of this session, participants should be able to: 1) Discuss how anterior and posterior spinal fusion techniques differ in terms of reoperation and complication rates, and 2) Better weigh the potential benefits and risks of different surgical options for patients with degenerative lumbar spine disease.