BACTERIAL ADHERENCE AND BIOFILM STUDY

dgarcia

Characterization of the Adherence Patterns and Biofilm Density of Commonly Encountered Bacterial Pathogens to Spinal Instrumentation of Differing Compositions

Background

  • Infections are one of the most pressing problems in orthopaedic surgery.
  • Very little information on ability of implant materials to minimize infection.
  • Grow most prevalent orthopaedic pathogens on the most commonly utilized orthopaedic implant materials.
  • Utilize Scanning Electron Microscopy (SEM) and Confocal-Laser Scanning Microscopy (CLSM) with fluorescent-conjugated antibodies to determine adherence density and patterns on materials.

Methodology

  • 6 Clinically-Isolated Pathogens
    • Methicillin-Resistant S. aureus
    • Methicillin-Sensitive S. aureus
    • Coagulase-Negative S. epidermidis
    • Multidrug-Resistant A. baumannii
    • Propionibacterium acnes
    • Vancomycin-Resistant E. faecalis 
  • 5 Commonly Utilized Spinal Implant Materials
    • Polyetheretherketone (PEEK)
    • Cobalt Chromium (CoCr)
    • Stainless Steel (SS)
    • Titanium (Ti)
    • Titanium Alloy (TiA)
  • Microscopy Techniques
    • Scanning Electron Microscopy  (SEM)
    • Confocal Laser Scanning Microscopy (CLSM) and Fluorescent-Conjugated Antibodies (FCAs)

Results

Fig 1.  Area  coverage and density of colony forming units (CFUs) of Methicillin-Resistant S. aureus  A) Titanium B) Stainless Steel C) Cobalt Chromium D) PEEK E) Titanium Alloy.

Fig 2 A. % Area Coverage of  Methicillin-Resistant S. aureus.

Fig 2 B. CFU per area of Methicillin-Resistant S. aureus.

Fig 3. Area  coverage and density of colony forming units (CFUs) of Multi-Drug Resistant A. baumannii A) Titanium B) Stainless Steel C) Cobalt Chromium D) PEEK E) Titanium Alloy.

Fig 4. A. % Area Coverage of  Multi-Drug Resistant A. baumannii.

Fig 4 B. CFU per area of Multi-Drug Resistant A. baumannii.
Fig 5. Area  coverage and density of colony forming units (CFUs) of Coagulase-Negative S. epidermidis A) Titanium B) Stainless Steel C) Cobalt Chromium D) PEEK E) Titanium Alloy.

Fig 6 A. % Area  coverage of Coagulase-Negative S. epidermidis.

Fig 6 B. CFU per area of Coagulase-Negative S. epidermidis.

Conclusion

  • No single implant material is able to reduce bacterial adherence of all of the pathogens tested.
  • Cobalt Chromium and PEEK have highest level of bacterial adherence.
  • Stainless Steel and Titanium Alloy have the least amount of bacterial adherence.
  • Adherence appears to be guided by surface microtopography of materials.