Emerging intraoperative diagnostic modalities for fracture-related infection: A scoping review

Fracture-related infection (FRI) remains a challenge in orthopedic trauma care. Conventional culturing of deep intraoperative samples is the current diagnostic standard, but confirmation occurs postoperatively, delaying targeted treatment. Real-time intraoperative diagnostic techniques may offer earlier, more precise detection and improved surgical decision-making, but their clinical value remains uncertain and requires further investigation.

A scoping review was conducted in accordance with PRISMA-ScR guidelines using the JBI PCC framework. Studies were included if they assessed any intraoperative diagnostic technique in patients with confirmed or suspected FRI or in relevant experimental models. Data on study design, population, technique characteristics, outcomes and key findings were charted and synthesised narratively.

Seven studies met the inclusion criteria, covering two categories of intraoperative techniques: frozen section analysis (n = 3) and fluorescence-based imaging (n = 4). Frozen section analysis demonstrated variable diagnostic performance. One diagnostic accuracy study in upper-limb nonunion surgery reported high sensitivity (88%), specificity (96%) and negative predictive value (98%), whereas a prospective cohort of revision fracture surgery for presumed aseptic failure showed low sensitivity (0%) for detecting indolent infection. Studies assessing intraoperative diagnostic modalities for FRI were heterogeneous in terms of study design, populations, and reference standards. Studies focusing on fluorescence-based imaging were predominantly experimental, including bacterial-targeted fluorescent tracers, fluorescence-assisted assessment of bone viability, and perfusion-based imaging. These techniques consistently demonstrated technical feasibility in ex vivo models, murine infection models, and small clinical feasibility studies, but none have been evaluated in larger FRI cohorts.

The evidence base for intraoperative diagnostic modalities in FRI is limited. Frozen section analysis is the most established method but shows variable performance across clinical contexts. Fluorescence-based intraoperative imaging techniques seem promising but remain largely developmental. In particular, vancomycin-based fluorescent tracers have shown strong preclinical performance and may enable targeted, real-time visualization of bacterial infections during surgery. Further prospective clinical studies using consistent diagnostic frameworks and validated reference standards are needed to clarify their value in FRI.