Surgical site infection and antibiogram within 90 days of elective intramedullary nail fixation of femoral and tibial diaphyseal fractures: A prospective case series of adult patients at a tertiary hospital in Lusaka, Zambia

Abstract

Background: Surgical site infections (SSIs) represent frequent complications in orthopaedic surgery. These challenging and typically protracted conditions can lead to deep bone and implant infections. Notwithstanding the reported delays in fracture repair associated with open reduction and internal fixation, a dearth of information exists regarding SSI rates and antibiograms following intramedullary nailing for femoral and tibia diaphyseal fractures.

Methods: This prospective case series, conducted from September 2019 through August 2020, enrolled adults undergoing elective intramedullary nailing for femoral and tibial fractures at a tertiary care centre in Lusaka, Zambia. Skeletally mature patients with closed diaphyseal fractures of the femur or tibia were eligible for inclusion, and we excluded patients with pathological fractures and established spine injuries, as well as those who missed any planned clinic visits within the 90-day active postoperative surveillance period. Recruitment was affected by implant availability and COVID-19–related shutdowns. Information was gathered from participant interviews, medical records, and laboratory investigations, with a 90-day postoperative surveillance period. SSIs were assessed according to NHSN (National Healthcare Safety Network, US Centers for Disease Control and Prevention) criteria. Significance set at a P value < 0.05. Continuous variables were tested for normality, with skewed data presented as medians and interquartile ranges, while categorical variables were analysed to generate frequencies and percentages. Multivariate analysis was employed to evaluate potential risk factors for SSI.

Results: Of the 132 participants, the median age was 30 years (interquartile range, 25-42). The study identified an SSI rate of 15.9%. Among the participants with SSI, 23.8% subsequently developed deep bone infections necessitating explantation. Multivariate analysis indicated that—compared with tibial fractures—femoral diaphyseal fractures were associated with lower odds of developing SSI (adjusted odds ratio, 0.08; 95% confidence interval, 0.02-0.35; P=0.001). Staphylococcus aureus, predominantly methicillin-resistant S. aureus, was the most commonly isolated pathogen.

Conclusions: Both the SSI rate and the prevalence of methicillin-resistant S. aureus were higher than globally accepted standards. This information is crucial for the development of locally relevant strategies for SSI case management.