Inflammatory Biomarkers Following Orthopedic Surgery: Current Evidence, Clinical Applications, and Future Perspectives—A Narrative Review

Orthopedic procedures trigger a complex inflammatory response that plays a central role in tissue repair and postoperative recovery. However, excessive or dysregulated inflammation may contribute to complications such as periprosthetic joint infection, thromboembolic events, delayed healing, or systemic organ dysfunction. Therefore, accurate perioperative monitoring of inflammatory activity has become increasingly important in orthopedic surgery. Evidence discussed in this review was identified through a literature search of PubMed, Scopus, and Web of Science databases covering publications from 2000 to 2026. This narrative review summarizes the current evidence regarding both traditional inflammatory biomarkers, including C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), procalcitonin (PCT), and D-dimers, as well as emerging biomarkers derived from complete blood count (CBC), such as the neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), systemic inflammatory response index (SIRI), and aggregate index of systemic inflammation (AISI). Particular attention is devoted to the clinical utility of these biomarkers in orthopedic trauma, fracture healing, total joint arthroplasty, and the early detection of postoperative complications. Increasing evidence suggests that composite CBC-derived indices may provide a practical and cost-effective approach for perioperative risk stratification and prognosis assessment. Nevertheless, their interpretation remains challenging due to the lack of standardized cutoff values and the influence of multiple patient-related factors. Current evidence indicates that assessing biomarker kinetics and interpreting multiple inflammatory indices together may be more clinically valuable than isolated measurements. Future research should focus on standardization, validation in prospective studies, and integration of inflammatory biomarkers into personalized perioperative care pathways in orthopedic surgery.