Objectives. Infection of implants is a major problem in elective and trauma surgery. Heating is an effective way to reduce the bacterial load in food preparation, and studies on hyperthermia treatment for cancer have shown that it is possible to heat metal objects with pulsed electromagnetic fields selectively (PEMF), also known as induction heating. We therefore set out to answer the following research question: is non-contact induction heating of metallic implants effective in reducing bacterial load in vitro?. Methods. Titanium alloy cylinders (Ti6Al4V) were exposed to PEMF from an induction heater with maximum 2000 watts at 27 kHz after being contaminated with five different types of micro-organisms: Staphylococcus epidermidis; Staphylococcus aureus; Pseudomonas aeruginosa; spore-forming Bacillus cereus; and yeast Candida albicans. The cylinders were exposed to incremental target temperatures (35°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C) for up to 3.5 minutes. Results. There was an average linear heating rate of 0.39°C per second up to the target temperature, and thereafter the target temperature was maintained until the end of the experiment. At 60°C and higher (duration 3.5 minutes), there was a 6-log reduction or higher for every micro-organism tested. At 60°C, we found that the shortest duration of effective induction heating was 1.5 minutes. This resulted in a 5-log reduction or higher for every micro-organism tested. Conclusion. Non-contact induction heating of a titanium disk is effective in reducing bacterial load in vitro. These promising results can be further explored as a new treatment modality for infections of metal orthopaedic implants. Cite this article: B. G. Pijls, I. M. J. G. Sanders, E. J. Kuijper, R. G. H. H. Nelissen. Non-contact electromagnetic induction heating for eradicating bacteria and yeasts on biomaterials and possible relevance to
Aims. Biofilm infections are among the most challenging complications in orthopaedics, as bacteria within the biofilms are protected from the host immune system and many antibiotics. Halicin exhibits broad-spectrum activity against many planktonic bacteria, and previous studies have demonstrated that halicin is also effective against Staphylococcus aureus biofilms grown on polystyrene or polypropylene substrates. However, the effectiveness of many antibiotics can be substantially altered depending on which orthopaedically relevant substrates the biofilms grow. This study, therefore, evaluated the activity of halicin against less mature and more mature S. aureus biofilms grown on titanium alloy, cobalt-chrome, ultra-high molecular weight polyethylene (UHMWPE), devitalized muscle, or devitalized bone. Methods. S. aureus-Xen36 biofilms were grown on the various substrates for 24 hours or seven days. Biofilms were incubated with various concentrations of halicin or vancomycin and then allowed to recover without antibiotics. Minimal biofilm eradication concentrations (MBECs) were defined by CFU counting and resazurin reduction assays, and were compared with the planktonic minimal inhibitory concentrations (MICs). Results. Halicin continued to exert significantly (p < 0.01) more antibacterial activity against biofilms grown on all tested orthopaedically relevant substrates than vancomycin, an antibiotic known to be affected by biofilm maturity. For example, halicin MBECs against both less mature and more mature biofilms were ten-fold to 40-fold higher than its MIC. In contrast, vancomycin MBECs against the less mature biofilms were 50-fold to 200-fold higher than its MIC, and 100-fold to 400-fold higher against the more mature biofilms. Conclusion. Halicin is a promising antibiotic that should be tested in animal models of
Biofilm-related infection is a major complication that occurs in orthopaedic surgery. Various treatments are available but efficacy to eradicate infections varies significantly. A systematic review was performed to evaluate therapeutic interventions combating biofilm-related infections on in vivo animal models. Literature research was performed on PubMed and Embase databases. Keywords used for search criteria were “bone AND biofilm”. Information on the species of the animal model, bacterial strain, evaluation of biofilm and bone infection, complications, key findings on observations, prevention, and treatment of biofilm were extracted.Aims
Methods
Aims. Continuous local antibiotic perfusion (CLAP) has recently attracted attention as a new drug delivery system for
Aims. There is a considerable challenge in treating bone infections and
Objectives. Thermal stability is a key property in determining the suitability of an antibiotic agent for local application in the treatment of
We aimed to determine the concentrations of synovial vancomycin and meropenem in patients treated by single-stage revision combined with intra-articular infusion following periprosthetic joint infection (PJI), thereby validating this drug delivery approach. We included 14 patients with PJI as noted in their medical records between November 2021 and August 2022, comprising eight hip and seven knee joint infections, with one patient experiencing bilateral knee infections. The patients underwent single-stage revision surgery, followed by intra-articular infusion of vancomycin and meropenem (50,000 µg/ml). Synovial fluid samples were collected to assess antibiotic concentrations using high-performance liquid chromatography.Aims
Methods
This study aimed to explore the role of small colony variants (SCVs) of A PJI diagnosis was made according to the MusculoSkeletal Infection Society (MSIS) for PJI. Bone and tissue samples were collected intraoperatively and the intracellular invasion and intraosseous colonization were detected. Transcriptomics of PJI samples were analyzed and verified by polymerase chain reaction (PCR).Aims
Methods
Poly(methyl methacrylate) (PMMA)-based bone cements are the industry standard in orthopaedics. PMMA cement has inherent disadvantages, which has led to the development and evaluation of a novel silorane-based biomaterial (SBB) for use as an orthopaedic cement. In this study we test both elution and mechanical properties of both PMMA and SBB, with and without antibiotic loading. For each cement (PMMA or SBB), three formulations were prepared (rifampin-added, vancomycin-added, and control) and made into pellets (6 mm × 12 mm) for testing. Antibiotic elution into phosphate-buffered saline was measured over 14 days. Compressive strength and modulus of all cement pellets were tested over 14 days.Aims
Methods
Periprosthetic joint infections (PJIs) and osteomyelitis are clinical challenges that are difficult to eradicate. Well-characterized large animal models necessary for testing and validating new treatment strategies for these conditions are lacking. The purpose of this study was to develop a rabbit model of chronic PJI in the distal femur. Fresh suspensions of Aims
Methods
In orthopaedic and trauma surgery, implant-associated infections are increasingly treated with local application of antibiotics, which allows a high local drug concentration to be reached without eliciting systematic adverse effects. While ceftriaxone is a widely used antibiotic agent that has been shown to be effective against musculoskeletal infections, high local concentrations may harm the surrounding tissue. This study investigates the acute and subacute cytotoxicity of increasing ceftriaxone concentrations as well as their influence on the osteogenic differentiation of human bone progenitor cells. Human preosteoblasts were cultured in presence of different concentrations of ceftriaxone for up to 28 days and potential cytotoxic effects, cell death, metabolic activity, cell proliferation, and osteogenic differentiation were studied.Aims
Methods
In contrast to operations performed for other fractures, there is a high incidence rate of surgical site infection (SSI) post-open reduction and internal fixation (ORIF) done for tibial plateau fractures (TPFs). This study investigates the effect of induced membrane technique combined with internal fixation for managing SSI in TPF patients who underwent ORIF. From April 2013 to May 2017, 46 consecutive patients with SSI post-ORIF for TPFs were managed in our centre with an induced membrane technique. Of these, 35 patients were included for this study, with data analyzed in a retrospective manner.Aims
Methods
In wound irrigation, 1 mM ethylenediaminetetraacetic acid (EDTA) is more efficacious than normal saline (NS) in removing bacteria from a contaminated wound. However, the optimal EDTA concentration remains unknown for different animal wound models. The cell toxicity of different concentrations of EDTA dissolved in NS (EDTA-NS) was assessed by Cell Counting Kit-8 (CCK-8). Various concentrations of EDTA-NS irrigation solution were compared in three female Sprague-Dawley rat models: 1) a skin defect; 2) a bone exposed; and 3) a wound with an intra-articular implant. All three models were contaminated with Aims
Methods
Flucloxacillin is commonly administered intravenously for perioperative antimicrobial prophylaxis, while oral administration is typical for prophylaxis following smaller traumatic wounds. We assessed the time, for which the free flucloxacillin concentration was maintained above the minimum inhibitory concentration ( A total of 16 pigs were randomly allocated to either intravenous (Group IV) or oral (Group PO) flucloxacillin 1 g every six hours during a 24-hour period. Microdialysis was used for sampling in cancellous and cortical bone, subcutaneous tissue, and the knee joint. In addition, plasma was sampled. The flucloxacillin Aims
Methods
CERAMENT|G is an absorbable gentamicin-loaded biocomposite used as an on-site vehicle of antimicrobials for the treatment of chronic osteomyelitis. The purpose of the present study was to investigate the sole effect of CERAMENT|G, i.e. without additional systemic antimicrobial therapy, in relation to a limited or extensive debridement of osteomyelitis lesions in a porcine model. Osteomyelitis was induced in nine pigs by inoculation of 104 colony-forming units (CFUs) of Aims
Methods
The objective of this study was to characterize the effect of rifampin incorporation into poly(methyl methacrylate) (PMMA) bone cement. While incompatibilities between the two materials have been previously noted, we sought to identify and quantify the cause of rifampin’s effects, including alterations in curing properties, mechanical strength, and residual monomer content. Four cement groups were prepared using commercial PMMA bone cement: a control; one with 1 g of rifampin; and one each with equimolar amounts of ascorbic acid or hydroquinone relative to the amount of rifampin added. The handling properties, setting time, exothermic output, and monomer loss were measured throughout curing. The mechanical strength of each group was tested over 14 days. A radical scavenging assay was used to assess the scavenging abilities of rifampin and its individual moieties.Objectives
Methods
The objective of this study was to compare the elution characteristics,
antimicrobial activity and mechanical properties of antibiotic-loaded
bone cement (ALBC) loaded with powdered antibiotic, powdered antibiotic
with inert filler (xylitol), or liquid antibiotic, particularly focusing
on vancomycin and amphotericin B. Cement specimens loaded with 2 g of vancomycin or amphotericin
B powder (powder group), 2 g of antibiotic powder and 2 g of xylitol
(xylitol group) or 12 ml of antibiotic solution containing 2 g of
antibiotic (liquid group) were tested.Objectives
Methods
A clinical investigation into a new bone void filler is giving
first data on systemic and local exposure to the anti-infective
substance after implantation. A total of 20 patients with post-traumatic/post-operative bone
infections were enrolled in this open-label, prospective study.
After radical surgical debridement, the bone cavity was filled with
this material. The 21-day hospitalisation phase included determination
of gentamicin concentrations in plasma, urine and wound exudate, assessment
of wound healing, infection parameters, implant resorption, laboratory
parameters, and adverse event monitoring. The follow-up period was
six months. Objective
Method
The most concerning infection of allografts and operative procedures
is methicillin resistant An iontophoresis cell was set up with varying concentrations
of Vancomycin within the medulla of a section of sheep tibia, sealed
from an external saline solution. The cell was run for varying times,
Vancomycin concentrations and voltages, to gain information on optimisation
of conditions for impregnating the graft. Each graft was then sectioned
and dust ground from the exposed surface. The dust was serially
washed to extract the Vancomycin and concentrations measured and
plotted for all variables tested.Objectives
Methods
