Quiescent non-union: Acknowledging a discrete entity and comparing serological markers for diagnosis of infection at non-union site.

BACKGROUND: Quiescent non-union refers to a state where a fracture fails to heal, and the site appears clinically inactive despite the possible presence of a dormant or low-grade infection. This condition often follows open fractures or prior surgical interventions. Although typical signs of infection-pain, swelling, or discharge-are absent, latent infections may reactivate, leading to severe complications. Diagnosing infection in such cases is challenging due to the lack of definitive tools, and clinicians typically rely on inflammatory markers like C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and total leukocyte count (TLC), though their reliability remains uncertain.

OBJECTIVE: To determine the prevalence of infection in patients with quiescent non-union of long bone diaphyseal fractures and evaluate the diagnostic performance of various microbiological and serological tests.

METHODOLOGY: This cross-sectional study was conducted at a tertiary care centre from December 2019 to January 2022, involving 50 patients with long bone non-unions. Radiographs classified non-union types. Intraoperatively, four tissue samples (from bone ends and surrounding soft tissue) were collected for microbiological analysis. Preoperative blood samples assessed TLC, ESR, and CRP levels.

RESULTS: Of 50 patients, 10 (20 %) had positive microbial cultures. Among serological tests, TLC had 20 % sensitivity and 56 % accuracy; ESR had 40 % sensitivity and 64 % accuracy. CRP demonstrated the highest sensitivity (60 %) and diagnostic accuracy (76 %).

CONCLUSION: Occult infection may be present in quiescent non-unions. CRP is the most reliable serological marker for detecting such hidden infections.