Initial peri- and postoperative antibiotic treatment of infected nonunions: results from 212 consecutive patients after mean follow-up of 34 months

Abstract

PurposeInfected nonunions of the long bones belong to the most feared complications in the field of orthopedic and trauma surgery. Optimal antibiotic therapy should start early with the first revision surgery. Therefore, the aim of this study was to evaluate our peri- and postoperative antibiotic regime in context with the microbial spectrum and antibiotic resistances of patients with infected nonunions and to assess the possible impact on healing rates.MethodsWe included all patients with first revision surgery during 2010–2015 due to nonunion of long bones with a clinical history of infection treated with radical debridement, local application of a gentamicin-impregnated bone cement, and systemic cefuroxime. Mean follow-up was 34.2 months. Data collection was performed retrospectively using a computerized databank with information about microbial species from intraoperatively acquired tissue samples and respective antibiograms. Bone fusion rates were evaluated based on findings of the latest X-rays and computed tomography scans.ResultsTwo hundred and twelve patients with nonunion and history of infection were selected; 171 patients had positive intraoperative microbial evidence of infection. Bacterial testing was mostly positive in fractures of the tibia (47.4%) and the femur (27.5%). Coagulase-negative Staphylococcus spp. were the most frequently detected (44.4%) followed by mixed infections (18.7%) and Staphylococcus aureus (10.5%). Antibiograms revealed that 62.6% of our cases were cefuroxime sensitive; 87.7% were gentamicin sensitive. Only 10.5% showed resistance to both cefuroxime and gentamicin. There was no statistically significant difference of fusion rates between patients with different microbial species or different antibiograms.ConclusionOur data suggest that besides the high variety of different detected species, initial antibiotic treatment with a combination of systemic cefuroxime and local gentamicin-loaded bone cement is effective and in almost 90% the later determined microbial infection was sensitive to this treatment. Therefore, we recommend initial treatment according to this algorithm until specific antibiograms are available from intraoperatively acquired tissue samples.

Does Age Influence the Outcome of Lower Limb Non-Union Treatment? A Matched Pair Analysis

“…Tissue samples were immediately processed after harvesting according to the standard of care of our microbiological department. Evidence of bacteria was determined as infection if obligate pathogen bacteria were detected or if more than two independent samples were positive for the same facultative pathogen bacteria [22]. Tissue processing in our microbiological department was performed as previously described [22,23].…”

“…In patients receiving the two-stage therapy, the first step was repeated until asepsis was achieved. Further information regarding antibiotic treatment have been published elsewhere [22].…”

A new sequential animal model for infection-related non-unions with segmental bone defect

“…The treatment of critical size bone defects resulting from trauma or posttraumatic osteomyelitis is still very challenging for the orthopedic surgeon and has major socio-economic consequences [3,19,20]. S. aureus is the most common bacterium in bone infection after open fractures [10,21,22]. Moreover, S. aureus infection is an established and well-investigated animal model to study osteomyelitis [4,23,24].…”

A study protocol for a Pilot Masked, Randomized Controlled Trial Evaluating Locally-applied Gentamicin versus Saline in Open Tibia Fractures (pGO-Tibia) in Dar es Salaam, Tanzania

“…An ideal local antibiotic for open fractures is (1) low cost, (2) readily available, (3) easily applied, (4) easily monitored for toxicity, and (5) active against the microbiological profile of the wound. The most common pathogens in fracture-related infection are Staphylococcus aureus , followed by Staphylococcus epidermidis , and gram-negative bacteria such as Escherichia coli and other Enterobacteriaceae species [ 17 , 18 ]. Gentamicin provides excellent coverage of these species with low rates of resistance, particularly when combined with systemic administration of a first-generation cephalosporin [ 19 ].…”