Elevated Alkaline Phosphatase Is Associated With Increased Rates of Pseudoarthrosis and Perioperative Complications Following Lumbar Fusion Surgery.

Abstract

Retrospective cohort study. This study explored the association between serum alkaline phosphatase (ALP) and the incidence of pseudoarthrosis, hospital readmission, and return to operating room (ROR) following lumbar spinal arthrodesis. Over the past 2 decades, lumbar spine fusions have increased due to an aging population and surgical advancements, but reoperation rates remain high due to complications like pseudoarthrosis, with elevated alkaline phosphatase (ALP) levels possibly predicting these issues. Data on lumbar arthrodesis patients with documented serum ALP levels were obtained from the American College of Surgeons National Quality Improvement Program (ACS-NSQIP) database (2015-2021). Univariate and multivariate models were used to examine the effect of ALP levels on pseudoarthrosis, readmission, and ROR. Further analyses stratified by American Society of Anesthesiologist (ASA) physical status classification. A total of 39,524 patients were included. Elevated ALP was significantly associated with pseudoarthrosis [odds ratio (OR) 1.62, 95% CI 1.03-2.55], readmission (OR 1.78, CI 1.29-2.45), and ROR (OR 2.00, CI 1.37-2.93) in univariate models. Elevated ALP was significantly associated with pseudoarthrosis (OR 1.63, CI 1.03-2.56), readmission (OR 1.65, CI 1.19-2.27), and ROR (OR 1.89, CI 1.27-2.72) in multivariate models. Stratifying by ASA, elevated ALP was associated with pseudoarthrosis (OR 2.60, CI 1.26-5.36) in ASA 2 and ROR (OR 1.78, CI 1.12-2.83) in ASA 3 patients. Elevated ALP is strongly associated with increased odds of pseudoarthrosis, readmission, and ROR after lumbar spinal arthrodesis and retained a strong association with pseudoarthrosis and ROR after ASA stratification. Conversely, low ALP levels may offer a protective effect against pseudoarthrosis, though not statistically significant. These results may inform surgeons of risks associated with elevated ALP levels before lumbar spine fusion surgery and highlight the importance of comprehensive medical optimization.