Introduction: Postoperative spinal infections remain critical, resource-intensive complications due to diagnostic challenges in distinguishing sterile inflammation from early sepsis. While conventional biomarkers often lack sufficient specificity, newer inflammatory indices offer potential for improved clinical surveillance. This study conducts a comparative analysis of serum biomarker profiles to determine their diagnostic accuracy in predicting surgical site infections following spinal surgery.

Material and methods: This descriptive cross-sectional study conducted at Shohada Hospital, Tabriz, enrolled 111 patients via convenience sampling (n = 111 based on Cochran’s formula). Demographic, surgical, and biomarker data were systematically extracted from medical records. Outcomes were analyzed using t-tests, chi-square tests, and multivariable logistic regression, following ethical approval by the Tabriz University of Medical Sciences.

Results: This study of 111 patients demonstrates that advanced age (P = 0.006) and elevated serum biomarkers (CRP, PCT, NLR; P<0.001) are strongly associated with postoperative spinal infection. Biomarker-based risk stratification effectively predicted infection incidence (P<0.001) and prolonged hospitalization (P<0.001). Furthermore, ROC analysis confirmed the superior diagnostic precision of postoperative day 3 CRP (AUC=0.924) and procalcitonin (AUC=0.898) compared to conventional white blood cell counts (P<0.001).

Conclusion: These findings highlight that early postoperative monitoring of inflammatory biomarkers, particularly C-reactive protein and procalcitonin, offers a robust diagnostic strategy for spinal infection. Implementing biomarker-based risk stratification allows for timely clinical intervention, potentially reducing infectious complications and hospitalization duration.