Risk Factors for Postoperative Complications in Different Fusion Surgical Approaches for Lumbar Degenerative Diseases

Objective: Posterior lumbar interbody fusion (PLIF), posterolateral fusion (PLF), and Hybrid fusion are widely used fusion procedures for lumbar degenerative diseases (LDDs). Postoperative complications dominated by cage migration (CM) and adjacent segment degeneration (ASD) remain major challenges. This study aimed to identify and compare the independent risk factors for CM and ASD in PLIF, PLF, and Hybrid fusion, so as to provide evidence-based references for preoperative evaluation, surgical selection, and complication prevention in clinical practice. Methods: A retrospective cohort study was conducted in patients who underwent PLIF, PLF, or Hybrid fusion for LDDs at our institution. Demographic data (age, gender, and body mass index [BMI]), lifestyle factors (smoking and insobriety), comorbidities (hypertension, diabetes, hyperuricemia, osteoporosis, and hypoalbuminemia), surgical parameters (operative time, intraoperative blood loss, fusion segments, and lumbar lordosis angle), radiological indices (Pfirrmann grading of intervertebral disc degeneration and relative disc height), and biological markers (C-reactive protein/lymphocyte ratio [CLR], procalcitonin [PCT], and serum amyloid A [SAA]) were collected. Patients were stratified into complication and non-complication groups based on the occurrence of CM or ASD. Univariate and binary logistic regression analyses were performed to determine independent risk factors for postoperative complications. Results: A total of 203 patients were enrolled, including 80 cases with complications in the PLIF group, 64 in the Hybrid group, and 59 in the PLF group. No significant differences were noted in the distribution of complication types among the three groups (p = 0.179). Univariate analysis revealed that BMI, osteoporosis, the Pfirrmann grading of superior adjacent disc degeneration, lumbar lordosis angle, operative time, and intraoperative blood loss were significantly associated with postoperative complications across all three surgical groups (p < 0.05). Binary logistic regression analysis confirmed that elevated BMI (PLIF: OR = 1.18, 95%CI: 1.05-4.38; PLF: OR = 1.19, 95%CI: 0.76-2.18; Hybrid: OR = 1.14, 95%CI: 1.07-2.54), osteoporosis (PLIF: OR = 6.86; PLF: OR = 7.62; Hybrid: OR = 5.62), advanced superior adjacent disc degeneration (PLIF: OR = 8.04; PLF: OR = 4.49; Hybrid: OR = 2.87), prolonged operative time, and increased intraoperative blood loss were independent risk factors for postoperative complications. In contrast, age, gender, smoking, insobriety, hypertension, diabetes, CLR, PCT, and SAA were not identified as risk factors (p* > 0.05). Conclusions: Elevated BMI, osteoporosis, pre-existing superior adjacent disc degeneration, prolonged operative time, and increased intraoperative blood loss are shared independent risk factors for CM and ASD following PLIF, PLF, and Hybrid fusion for LDDs. Targeted interventions addressing these factors may reduce postoperative complication rates and improve patient outcomes.