Incidence of Adjacent Segment Degeneration and Its Associated Risk Factors Following Anterior Cervical Discectomy and Fusion: A Meta-Analysis

Abstract

This study aimed to investigate the incidence of adjacent segment degeneration (ASD) and its associated risk factors in adults after anterior cervical discectomy and fusion (ACDF) surgery. An exhaustive search across multiple databases was conducted, including Embase, PubMed, Cochrane Library, and the Web of Science, to identify pertinent studies. We collected such patient data as demographic variables (including age, gender, body mass index), cervical spondylosis type (such as radiculopathy and myelopathy), diabetes status, smoking and drinking history, and radiological risk factors (such as preoperative ASD status, developmental spinal stenosis, T1 slope, and postoperative less cervical lordosis). Incidence estimates were calculated based on relevant data. Risk factors were assessed using odds ratios and weighted mean differences with 95% confidence intervals (CIs). Our analysis incorporated a total of 21 studies for incidence analysis. The overall incidence of CASD following ACDF was found to be 11% and radiographical ASD was 30%. Old age (weighted mean difference=3.21; 95% CI: 0.06, 6.36; P=0.05), preoperative ASD status (odds ratio=2.65; 95% CI: 1.53, 4.60; P < 0.01), developmental spinal stenosis (odds ratio=2.46; 95% CI: 1.61, 3.77; P < 0.01), and postoperative reduction in cervical lordosis were identified as significant risk factors for the occurrence of CASD. The incidence of CASD following ACDF was 11%. Risk factors for CASD included old age, preoperative adjacent segment degeneration, developmental spinal stenosis, and postoperative reduction in cervical lordosis. These findings provide valuable insights for the assessment of adjacent segment disease risk after ACDF, aiding surgeons in diagnosis and treatment decisions.