Prognostic Role of Blood Inflammatory Composite Biomarkers in Dvt After Lower Extremity Fractures

This study aimed to comprehensively assess the most recent data on the prognostic effects of hematologic markers, including the neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), platelet to lymphocyte ratio (PLR), and systemic immune inflammation index (SII), on deep vein thrombosis (DVT) following lower limb fractures.

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. This study was registered in PROSPERO (CRD420251006336). We performed a comprehensive search in the PubMed, EMBASE, Web of Science, and Scopus electronic databases. Date of publication and language were not restricted. Standardized mean difference (SMD) with 95% confidence interval (CI) was calculated and all statistical analyses were performed using Stata 18 software.

Ten studies, involving a total of 6183 patients with lower extremity fractures, of whom 896 developed DVT, were included in the final analysis. The results indicated that, compared to the non-DVT group, patients with DVT had higher levels of NLR (SMD = 0.48, 95% CI = 0.02-0.94, p = 0.04) and SII (SMD = 1.01, 95% CI = 0.121.89, p = 0.02). However, PLR and MLR level was not different between the two groups. Among the evaluated biomarkers, SII demonstrated the highest specificity (80%, PLR = 74%), while NLR had the highest sensitivity (68%).

The literature supported that, compared to the non-DVT group, patients with DVT had higher levels of NLR and SII. Among these biomarkers, SII demonstrated the highest specificity, while NLR had the highest sensitivity. Composite inflammatory markers, particularly SII, may hold value in DVT risk stratification during post-fracture period.Level of Evidence: II.