Osteomyelitis Recurrence with Open Femur Fractures among Combat Casualties from Iraq and Afghanistan
David Tribble; Louis Lewandowski; Clinton K. Murray, MD, Murray, MD,; Joseph Petfield; Daniel Stinner; Margot Krauss; Amy Weintrob; Anuradha Ganesan; Tyler Warkentien; Joseph Hsu; Jamie Fraser; Denise Bennett; Adriana McClung; Lauren Greenberg; Jiahong Xu; Benjamin Potter
Background:Combat trauma-related open fractures are frequently complicated by recurrent osteomyelitis and have identifiable predictors of increased risk.
Hypothesis:Characteristics of open femur fracture osteomyelitis cases among wounded U.S. military personnel (2003-2009) and risk factors for infection recurrence were assessed in a retrospective case-case comparison.
Methods:Open fractures were classified using a modified Gustilo-Anderson (GA) scheme (accounting for traumatic transfemoral amputations [TFA]) and Orthopaedic Trauma Association Open Fracture Classification (OTA OFC). Osteomyelitis diagnoses were classified as definite/probable or possible using standardized National Healthcare Safety Network diagnostic criteria. Recurrence was defined as an osteomyelitis diagnosis at the original site 30 days after the initial course of treatment was completed. Risk factors for osteomyelitis recurrence were assessed among subjects who had ≥30 days of follow-up.
Results:A total of 103 osteomyelitis cases were assessed, of which 32 and 71 were classified as definite/probable and possible, respectively. There was no significant difference between the groups regarding GA (overall, 57% with GA-III, 40% with TFAs) and OTA OFC characteristics, timing of definitive surgery, and radiographic union (median: 128 days). A higher proportion of patients classified as definite/probable received vancomycin (75% vs 49%; p=0.018) and an extended duration of antibiotics (≥90 days; 34% vs 3%; p<0.001) compared to the possible group. Among 95 patients with ≥30 days of follow-up, 17 (18%) had an osteomyelitis recurrence with a median of 5 months (interquartile range: 3-8 months) from end of initial treatment to recurrence. Approximately 76% of patients with a recurrence received >21 days of antibiotics. Factors associated with fracture severity and management were assessed in a logistic regression model; however, only receipt of aminoglycosides for ≥5 days was independently associated with risk of osteomyelitis recurrence (odds ratio: 0.23; 95% confidence interval: 0.08-0.69). When timing of osteomyelitis recurrence was considered in a Kaplan-Meier plot, there was no significant association with injury severity or fracture classification.
Conclusions:No significant differences in clinical presentation or outcomes were observed based on osteomyelitis classification. Overall, disease recurrence is common among patients with combat-related open femur fractures diagnosed with osteomyelitis, so close monitoring is required as no independent risk factors for recurrence were identified except for use of aminoglycosides.