ABSTRACT
Background: We hypothesized that polymicrobial posttraumatic osteomyelitis (PTO) may be associated with worse outcomes when compared to monomicrobial PTO. We therefore attempted to show the outcomes and predisposing factors associated with polymicrobial PTO. Methods: A single-center case-control study was carried out from 2007 to 2012. The outcome variables analyzed were: the need for additional surgical and antibiotic treatments, rates of amputation, and mortality associated with the infection. Univariate and multivariable analyses using multiple logistic regression were performed to identify risk factors associated with polymicrobial PTO, and p < 0.05 was considered significant. Results: Among the 193 patients identified, polymicrobial PTO was diagnosed in 37.8%, and was significantly associated with supplementary surgical debridement (56.1% vs. 31%; p < 0.01), a higher consumption of antibiotics, and more amputations (6.5% vs 1.3%; p < 0.01). Factors associated with polymicrobial PTO in the multivariable analysis were older age (odds ratio [OR] = 1.02, 95% confidence interval [CI] = 1.01 to 1.03, p = 0.04), working in agriculture (OR = 2.86, 95% CI = 1.05 to 7.79, p = 0.04), open fracture Gustilo type III (OR = 2.38, 95% CI = 1.02 to 5.56, p = 0.04), need for blood transfusion (OR = 2.15, 95% CI = 1.07 to 4.32, p = 0.03), and need for supplementary debridement (OR = 2.58, 95% CI = 1.29 to 5.16, p = 0.01). Conclusions: PTO is polymicrobial in more than one-third of patients, associated with extra surgical and clinical treatment, and worse outcomes including higher rates of amputation.
ABSTRACT
BACKGROUND: The incidence of posttraumatic osteomyelitis (PTO) is increasing despite new treatment strategies. Assessment of patients' outcomes following PTO is challenging due to multiple variables. The study goals are to determine the frequency of recurrence following PTO treatment and identify factors predisposing patients to treatment failure. METHODS: Between August 01, 2007 to August 30, 2012, a single-center retrospective cohort study was performed among 193 patients diagnosed with PTO following orthopedic surgery for fracture care. Bone and soft tissues were collected for cultures and PTO was defined according to CDC/NHSN criteria. Patient, injury, surgery-associated variables, and microbiological records were reviewed for risk factors associated to recurrence of PTO. Univariate and multivariable analyses using logistic regression were performed, with p <0.05 considered significant. RESULTS: Thirty-eight patients (20%) of 192 diagnosed and treated for PTO failed their treatment. Factors associated with recurrence were age between 61 and 80 years [hazard ratio (HR) = 6.086, 95% confidence interval (CI) = 2.459;15.061, p = <0.001], age above 80 years [HR = 9.975 (95% CI = 3.591;27.714), p = <0.001], intraoperative blood transfusion [HR = 2.239 (95% CI = 1.138;4.406), p = 0.020], and positive culture for Pseudomonas aeruginosa [HR = 2.700 (95% CI = 1.370;5.319), p = 0.004]. CONCLUSIONS: Risk factors associated with recurrence of PTO are difficult to measure. The present study revealed that elderly patients, intraoperative blood transfusions, and infection due to P. aeruginosa were independently associated with recurrence of PTO. These factors should warn clinicians of a higher failure rate following treatment of PTO. Trial registration: ISRCTN71648577. Registered 18 May 2017. Retrospectively registered.
