Bacteriological Profile and Infection Risk Factors Following Internal Fixation of Long Bone Fractures A Prospective Analysis

Abstract

Background: Surgical site infections (SSIs) remain a major complication following internal fixation of long bone fractures, leading to prolonged recovery, increased healthcare costs, and poor outcomes. Common pathogens include Staphylococcus aureus and Gram-negative bacilli, with rising antibiotic resistance complicating treatment. Risk factors span patient-related issues, such as diabetes and smoking, to procedural aspects like prolonged operative time. Effective prevention relies on aseptic techniques and targeted antibiotic prophylaxis. Methods: A prospective observational study was conducted in the Department of Orthopaedic Surgery at Dhaka Medical College Hospital (DMCH) over a two-year period from June 2022 to May 2024. The study included 56 patients who underwent internal fixation for long bone fractures. Detailed data were collected on patient demographics, comorbid conditions, fracture classifications, and surgical parameters. Perioperative microbiological samples were systematically obtained, and postoperative infections were categorized as superficial, deep, or implant-related. The antibiotic resistance profiles of the isolated pathogens were comprehensively analyzed. Rigorous statistical methods, including chi-square tests, logistic regression analysis, and Kaplan-Meier survival analysis, were employed to evaluate the findings. Results: The overall post-operative infection rate was 38%. The predominant pathogens identified were Staphylococcus aureus (36%), Escherichia coli (16%), and Propionibacterium acnes (12%). Key risk factors for infection included advanced age (≥40 years), diabetes mellitus, smoking, malnutrition, open fractures, and prolonged operative times. Non-standard sterilization protocols and the presence of open fractures significantly increased infection rates. Multivariate logistic regression revealed that age ≥40 years, diabetes mellitus, smoking, open fractures, and non-standard sterilization were independent risk factors for infection. Conclusion: Post-operative infections following internal fixation are influenced by multiple patient-related and surgery-related factors. Early identification of at-risk patients and adherence to strict sterilization protocols are crucial for reducing infection rates. The findings highlight the importance of tailored antibiotic protocols and preventive strategies to improve patient outcomes and minimize infection-related complications. Further research is needed to optimize management strategies and address antimicrobial resistance.