Is non-union of tibial shaft fractures due to nonculturable bacterial pathogens? A clinical investigation using PCR and culture techniques

Abstract

BackgroundNon-union continues to be one of the orthopedist’s greatest challenges. Despite effective culture methods, the detection of low-grade infection in patients with non-union following tibial fracture still presents a challenge. We investigated whether “aseptic” tibial non-union can be the result of an unrecognized infection.MethodsA total of 23 patients with non-union following tibial shaft fractures without clinical signs of infection were investigated. Intraoperative biopsy samples obtained from the non-union site were examined by means of routine culture methods and by polymerase chain reaction (PCR) for the detection of 16 S ribosomal RNA (rRNA). Control subjects included 12 patients with tibial shaft fractures.Results23 patients (8 women and 15 men; mean age: 47.4 years) were included into this study. Preoperative C-reactive protein levels (mean: 20.8 mg/l) and WBC counts (mean: 8,359/μl) in the study group were not significantly higher than in the control group. None of the samples of non-union routine cultures yielded microorganism growth. Bacterial isolates were found by conventional culturing methods in only 1 case of an open fracture from the control group. In this case, PCR yielded negative results. 16 S rRNA was detected in tissue specimens from 2 patients (8.7%) with non-union. The analysis of these variable species-specific sequences enabled the identification of specific microorganisms (1x Methylobacterium species, 1x Staphylococcus species). Both PCR-positive patients were culture-negative.ConclusionsThe combination of microbiological culture and broad-range PCR seems to substantially add to the number of microbiological diagnoses obtained and may improve the clinican’s ability to tailor therapy to the individual patient’s needs.

Current Concepts and Ongoing Research in the Prevention and Treatment of Open Fracture Infections

“…This method is also ideal as a basic starting point because it does not require any sequencing of the bacterial genome, as primers are designed to regions of the 16S rRNA gene that are conserved throughout a broad range of prokaryotic taxa. Although this method is used in research laboratories, 4,23 it has not yet been implemented in clinical settings.…”

“…3 nonunion/malunion cases. 4 Further, while the importance of microbes in open fracture healing is accepted as significant, there is still little known about how or what microbes affect these wounds, or how we can use microbes diagnostically to predict complications and better inform treatment. The goal of current research is to address the deficiencies in the current paradigms of open fracture care, and to improve prevention and treatment of open fracture infection.…”

Long Bone Non-Unions and Malunions: Risk Factors and Treatment Outcomes in Calabar, Southern Nigeria

“…They include the involved bone and bony region injured, the degree of soft tissue injury, patient's age, the presence of co-morbidities, smoking and non-steroidal anti-inflammatory drug (NSAID) abuse. Unstable fixation, excessive iatrogenic stripping of the periosteum, infection, malnutrition, chronic alcoholism and injudicious interventions by traditional bonesetters are other risk factors for nonunions [1,5,[6][7][8].…”

Low-Grade-Infekt

“…einer Infektpseudarthrose. Dies kann dazu führen, dass LowGrade-Infekte nicht als solche diagnostiziert werden oder die Diagnosestellung deutlich verspätet erfolgt [7,9].…”

“…Eine zuverlässige Diagnose von LowGrade-Infekten ist zum gegenwärtigen Zeitpunkt jedoch nicht möglich [7,9]. Die zur Verfügung stehenden diagnostischen Verfahren bzw.…”