Anterior Lumbar Interbody Fusion With and Without Previous Abdominal Surgery: Analysis of 5,356 Cases

<title>Abstract</title> <p> <bold>Purpose:</bold> To evaluate the impact of previous abdominal surgery on intraoperative injuries during anterior lumbar interbody fusion (ALIF) and determine whether anatomical risk stratification better predicts intraoperative morbidity than prior surgery alone. <bold>Methods:</bold> A retrospective consecutive cohort study included 5,356 adults who underwent ALIF between April 2019 and May 2025. Patients were stratified into two groups: with previous abdominal surgery (n=2,725) and without previous abdominal surgery (n=2,631). Prior procedures were further classified as low, moderate, or high risk according to their anatomical relevance to the anterior ALIF access corridor. The primary outcome was any intraoperative injury. Multivariable logistic regression and 1:1 propensity score matching were performed to improve group comparability and reduce the influence of potential confounding. <bold>Results:</bold> Among patients with and without previous abdominal surgery, intraoperative injuries occurred in 95 of 2,725 (3.5%) and 78 of 2,631 (2.96%) patients, respectively (p=0.0963). In the adjusted model, previous abdominal surgery was not independently associated with intraoperative injury (OR 1.42, 95% CI 0.98-2.04; p=0.061), whereas high-risk prior procedures were associated with higher injury odds (OR 1.99, 95% CI 1.07-3.71; p=0.030). The number of previous abdominal surgeries was not independently associated with injury. After propensity score matching, intraoperative injuries occurred in 4.4% of patients with previous abdominal surgery and 3.1% of those without previous surgery (p=0.093). <bold>Conclusion:</bold> Previous abdominal surgery alone was not associated with a significant increase in intraoperative injury during ALIF. Prior procedures with greater anatomical relevance to the anterior access corridor were associated with higher injury risk. </p>