NEW postoperative spine infection criteria standardize diagnosis across six domains, and a microbiology standalone criterion today.
Why a Standard Definition for Postoperative Spine Infection Matters
Postoperative spine infection is a serious and often devastating complication after spine surgery, yet clinicians and researchers have lacked a universally accepted diagnostic standard. In the literature assessed by the authors, reported postoperative spine infection rates ranged from 0% to over 20%, varying by surgical indication and invasiveness. This heterogeneity has complicated study comparisons and limited progress in evaluating diagnostic approaches and management strategies for postoperative spine infection.
Postoperative Spine Infection Definition Built by Delphi Consensus
A multispecialty workgroup used a systematic literature review to inform a modified Delphi consensus process aimed at establishing a standardized postoperative spine infection definition for research, diagnosis, and management. The expert panel included nine fellowship trained, board certified physicians with expertise in infectious diseases, orthopaedic and neurologic spine surgery, and musculoskeletal radiology. Iterative rounds focused on selecting diagnostic criteria, ranking their importance, grouping them into categories, and agreeing on a final constellation to support postoperative spine infection classification. The process achieved 100% consensus.
Postoperative Spine Infection Criteria Span Six Clinical Domains
The final postoperative spine infection framework incorporates six clinical domains: wound features, microbiology, imaging, inflammatory biomarkers, intraoperative findings, and histology. The definition designates a single microbiological standalone criterion as pathognomonic for postoperative spine infection: identification of a phenotypically indistinguishable organism from two or more deep operative site specimens. Alongside this, the authors describe additional primary and secondary supporting criteria, with specified combinations used to classify cases as definite or probable postoperative spine infection.
What the Definition Is Designed to Enable
The authors conclude that this multispecialty, society endorsed definition offers a standardized framework intended to balance sensitivity and specificity across diverse clinical scenarios. They argue that consistent case classification can strengthen postoperative spine infection research by improving comparability across studies and supporting more reliable interpretation of outcomes. Clinically, the framework aims to support diagnosis and management by aligning how teams integrate microbiology, imaging, biomarkers, operative findings, histology, and wound assessment when evaluating suspected postoperative spine infection.
Reference: Shaw JD et al. New Definition for Postoperative Spine Infection (PSI): From the Workgroup of the Musculoskeletal Infection Society (MSIS) and the European Bone & Joint Infection Society (EBJIS). Spine (Phila Pa 1976). 2025. doi:10.1097/BRS.0000000000005604.
