Advertisement for orthosearch.org.uk
Results 1 - 20 of 40
Results per page:
Bone & Joint Research
Vol. 13, Issue 11 | Pages 632 - 646
7 Nov 2024
Diaz Dilernia F Watson D Heinrichs DE Vasarhelyi E

Aims

The mechanism by which synovial fluid (SF) kills bacteria has not yet been elucidated, and a better understanding is needed. We sought to analyze the antimicrobial properties of exogenous copper in human SF against Staphylococcus aureus.

Methods

We performed in vitro growth and viability assays to determine the capability of S. aureus to survive in SF with the addition of 10 µM of copper. We determined the minimum bactericidal concentration of copper (MBC-Cu) and evaluated its sensitivity to killing, comparing wild type (WT) and CopAZB-deficient USA300 strains.


Bone & Joint Research
Vol. 13, Issue 10 | Pages 546 - 558
4 Oct 2024
Li Y Wuermanbieke S Wang F Mu W Ji B Guo X Zou C Chen Y Zhang X Cao L

Aims

The optimum type of antibiotics and their administration route for treating Gram-negative (GN) periprosthetic joint infection (PJI) remain controversial. This study aimed to determine the GN bacterial species and antibacterial resistance rates related to clinical GN-PJI, and to determine the efficacy and safety of intra-articular (IA) antibiotic injection after one-stage revision in a GN pathogen-induced PJI rat model of total knee arthroplasty.

Methods

A total of 36 consecutive PJI patients who had been infected with GN bacteria between February 2015 and December 2021 were retrospectively recruited in order to analyze the GN bacterial species involvement and antibacterial resistance rates. Antibiotic susceptibility assays of the GN bacterial species were performed to screen for the most sensitive antibiotic, which was then used to treat the most common GN pathogen-induced PJI rat model. The rats were randomized either to a PJI control group or to three meropenem groups (intraperitoneal (IP), IA, and IP + IA groups). After two weeks of treatment, infection control level, the side effects, and the volume of antibiotic use were evaluated.


Aims

This study investigated vancomycin-microbubbles (Vm-MBs) and meropenem (Mp)-MBs with ultrasound-targeted microbubble destruction (UTMD) to disrupt biofilms and improve bactericidal efficiency, providing a new and promising strategy for the treatment of device-related infections (DRIs).

Methods

A film hydration method was used to prepare Vm-MBs and Mp-MBs and examine their characterization. Biofilms of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli were treated with different groups. Biofilm biomass differences were determined by staining. Thickness and bacterial viability were observed with confocal laser scanning microscope (CLSM). Colony counts were determined by plate-counting. Scanning electron microscopy (SEM) observed bacterial morphology.


Bone & Joint Research
Vol. 13, Issue 8 | Pages 401 - 410
15 Aug 2024
Hu H Ding H Lyu J Chen Y Huang C Zhang C Li W Fang X Zhang W

Aims

This aim of this study was to analyze the detection rate of rare pathogens in bone and joint infections (BJIs) using metagenomic next-generation sequencing (mNGS), and the impact of mNGS on clinical diagnosis and treatment.

Methods

A retrospective analysis was conducted on 235 patients with BJIs who were treated at our hospital between January 2015 and December 2021. Patients were divided into the no-mNGS group (microbial culture only) and the mNGS group (mNGS testing and microbial culture) based on whether mNGS testing was used or not.


Bone & Joint Research
Vol. 13, Issue 8 | Pages 383 - 391
2 Aug 2024
Mannala GK Rupp M Walter N Youf R Bärtl S Riool M Alt V

Aims

Bacteriophages infect, replicate inside bacteria, and are released from the host through lysis. Here, we evaluate the effects of repetitive doses of the Staphylococcus aureus phage 191219 and gentamicin against haematogenous and early-stage biofilm implant-related infections in Galleria mellonella.

Methods

For the haematogenous infection, G. mellonella larvae were implanted with a Kirschner wire (K-wire), infected with S. aureus, and subsequently phages and/or gentamicin were administered. For the early-stage biofilm implant infection, the K-wires were pre-incubated with S. aureus suspension before implantation. After 24 hours, the larvae received phages and/or gentamicin. In both models, the larvae also received daily doses of phages and/or gentamicin for up to five days. The effect was determined by survival analysis for five days and quantitative culture of bacteria after two days of repetitive doses.


Bone & Joint Research
Vol. 13, Issue 7 | Pages 332 - 341
5 Jul 2024
Wang T Yang C Li G Wang Y Ji B Chen Y Zhou H Cao L

Aims

Although low-intensity pulsed ultrasound (LIPUS) combined with disinfectants has been shown to effectively eliminate portions of biofilm in vitro, its efficacy in vivo remains uncertain. Our objective was to assess the antibiofilm potential and safety of LIPUS combined with 0.35% povidone-iodine (PI) in a rat debridement, antibiotics, and implant retention (DAIR) model of periprosthetic joint infection (PJI).

Methods

A total of 56 male Sprague-Dawley rats were established in acute PJI models by intra-articular injection of bacteria. The rats were divided into four groups: a Control group, a 0.35% PI group, a LIPUS and saline group, and a LIPUS and 0.35% PI group. All rats underwent DAIR, except for Control, which underwent a sham procedure. General status, serum biochemical markers, weightbearing analysis, radiographs, micro-CT analysis, scanning electron microscopy of the prostheses, microbiological analysis, macroscope, and histopathology evaluation were performed 14 days after DAIR.


Bone & Joint Research
Vol. 13, Issue 3 | Pages 127 - 135
22 Mar 2024
Puetzler J Vallejo Diaz A Gosheger G Schulze M Arens D Zeiter S Siverino C Richards RG Moriarty TF

Aims

Fracture-related infection (FRI) is commonly classified based on the time of onset of symptoms. Early infections (< two weeks) are treated with debridement, antibiotics, and implant retention (DAIR). For late infections (> ten weeks), guidelines recommend implant removal due to tolerant biofilms. For delayed infections (two to ten weeks), recommendations are unclear. In this study we compared infection clearance and bone healing in early and delayed FRI treated with DAIR in a rabbit model.

Methods

Staphylococcus aureus was inoculated into a humeral osteotomy in 17 rabbits after plate osteosynthesis. Infection developed for one week (early group, n = 6) or four weeks (delayed group, n = 6) before DAIR (systemic antibiotics: two weeks, nafcillin + rifampin; four weeks, levofloxacin + rifampin). A control group (n = 5) received revision surgery after four weeks without antibiotics. Bacteriology of humerus, soft-tissue, and implants was performed seven weeks after revision surgery. Bone healing was assessed using a modified radiological union scale in tibial fractures (mRUST).


Bone & Joint Research
Vol. 13, Issue 3 | Pages 101 - 109
4 Mar 2024
Higashihira S Simpson SJ Morita A Suryavanshi JR Arnold CJ Natoli RM Greenfield EM

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).


Bone & Joint Research
Vol. 13, Issue 1 | Pages 40 - 51
11 Jan 2024
Lin J Suo J Bao B Wei H Gao T Zhu H Zheng X

Aims. To investigate the efficacy of ethylenediaminetetraacetic acid-normal saline (EDTA-NS) in dispersing biofilms and reducing bacterial infections. Methods. EDTA-NS solutions were irrigated at different durations (1, 5, 10, and 30 minutes) and concentrations (1, 2, 5, 10, and 50 mM) to disrupt Staphylococcus aureus biofilms on Matrigel-coated glass and two materials widely used in orthopaedic implants (Ti-6Al-4V and highly cross-linked polyethylene (HXLPE)). To assess the efficacy of biofilm dispersion, crystal violet staining biofilm assay and colony counting after sonification and culturing were performed. The results were further confirmed and visualized by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). We then investigated the efficacies of EDTA-NS irrigation in vivo in rat and pig models of biofilm-associated infection. Results. When 10 mM or higher EDTA-NS concentrations were used for ten minutes, over 99% of S. aureus biofilm formed on all three types of materials was eradicated in terms of absorbance measured at 595 nm and colony-forming units (CFUs) after culturing. Consistently, SEM and CSLM scanning demonstrated that less adherence of S. aureus could be observed on all three types of materials after 10 mM EDTA-NS irrigation for ten minutes. In the rat model, compared with NS irrigation combined with rifampin (Ti-6Al-4V wire-implanted rats: 60% bacteria survived; HXLPE particle-implanted rats: 63.3% bacteria survived), EDTA-NS irrigation combined with rifampin produced the highest removal rate (Ti-6Al-4V wire-implanted rats: 3.33% bacteria survived; HXLPE particle-implanted rats: 6.67% bacteria survived). In the pig model, compared with NS irrigation combined with rifampin (Ti-6Al-4V plates: 75% bacteria survived; HXLPE bearings: 87.5% bacteria survived), we observed a similar level of biofilm disruption on Ti-6Al-4V plates (25% bacteria survived) and HXLPE bearings (37.5% bacteria survived) after EDTA-NS irrigation combined with rifampin. The in vivo study revealed that the biomass of S. aureus biofilm was significantly reduced when treated with rifampin following irrigation and debridement, as indicated by both the biofilm bacterial burden and crystal violet staining. EDTA-NS irrigation (10 mM/10 min) combined with rifampin effectively removes S. aureus biofilm-associated infections both in vitro and in vivo. Conclusion. EDTA-NS irrigation with or without antibiotics is effective in eradicating S. aureus biofilm-associated infection both ex and in vivo. Cite this article: Bone Joint Res 2024;13(1):40–51


Bone & Joint Research
Vol. 12, Issue 9 | Pages 546 - 558
12 Sep 2023
Shen J Wei Z Wang S Wang X Lin W Liu L Wang G

Aims

This study aimed to evaluate the effectiveness of the induced membrane technique for treating infected bone defects, and to explore the factors that might affect patient outcomes.

Methods

A comprehensive search was performed in PubMed, Embase, and the Cochrane Central Register of Controlled Trials databases between 1 January 2000 and 31 October 2021. Studies with a minimum sample size of five patients with infected bone defects treated with the induced membrane technique were included. Factors associated with nonunion, infection recurrence, and additional procedures were identified using logistic regression analysis on individual patient data.


Bone & Joint Research
Vol. 12, Issue 2 | Pages 113 - 120
1 Feb 2023
Cai Y Liang J Chen X Zhang G Jing Z Zhang R Lv L Zhang W Dang X

Aims

This study aimed to explore the diagnostic value of synovial fluid neutrophil extracellular traps (SF-NETs) in periprosthetic joint infection (PJI) diagnosis, and compare it with that of microbial culture, serum ESR and CRP, synovial white blood cell (WBC) count, and polymorphonuclear neutrophil percentage (PMN%).

Methods

In a single health centre, patients with suspected PJI were enrolled from January 2013 to December 2021. The inclusion criteria were: 1) patients who were suspected to have PJI; 2) patients with complete medical records; and 3) patients from whom sufficient synovial fluid was obtained for microbial culture and NET test. Patients who received revision surgeries due to aseptic failure (AF) were selected as controls. Synovial fluid was collected for microbial culture and SF-WBC, SF-PNM%, and SF-NET detection. The receiver operating characteristic curve (ROC) of synovial NET, WBC, PMN%, and area under the curve (AUC) were obtained; the diagnostic efficacies of these diagnostic indexes were calculated and compared.


Bone & Joint Research
Vol. 11, Issue 12 | Pages 843 - 853
1 Dec 2022
Cai Y Huang C Chen X Chen Y Huang Z Zhang C Zhang W Fang X

Aims

This study aimed to explore the role of small colony variants (SCVs) of Staphylococcus aureus in intraosseous invasion and colonization in patients with periprosthetic joint infection (PJI).

Methods

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).


Bone & Joint Research
Vol. 11, Issue 9 | Pages 629 - 638
1 Sep 2022
Pijls BG Sanders IMJG Kuijper EJ Nelissen RGHH

Aims

Here we used a mature seven-day biofilm model of Staphylococcus aureus, exposed to antibiotics up to an additional seven days, to establish the effectiveness of either mechanical cleaning or antibiotics or non-contact induction heating, and which combinations could eradicate S. aureus in mature biofilms.

Methods

Mature biofilms of S. aureus (ATCC 29213) were grown on titanium alloy (Ti6Al4V) coupons for seven days and were subjected to the following treatments or their combinations: antibiotics, mechanical cleaning, or heat shock by induction heating of 60°C for one minute. Experiments were repeated at least five times.


Aims

Treatment outcomes for methicillin-resistant Staphylococcus aureus (MRSA) periprosthetic joint infection (PJI) using systemic vancomycin and antibacterial cement spacers during two-stage revision arthroplasty remain unsatisfactory. This study explored the efficacy and safety of intra-articular vancomycin injections for PJI control after debridement and cement spacer implantation in a rat model.

Methods

Total knee arthroplasty (TKA), MRSA inoculation, debridement, and vancomycin-spacer implantation were performed successively in rats to mimic first-stage PJI during the two-stage revision arthroplasty procedure. Vancomycin was administered intraperitoneally or intra-articularly for two weeks to control the infection after debridement and spacer implantation.


Bone & Joint Research
Vol. 11, Issue 5 | Pages 327 - 341
23 May 2022
Alagboso FI Mannala GK Walter N Docheva D Brochhausen C Alt V Rupp M

Aims

Bone regeneration during treatment of staphylococcal bone infection is challenging due to the ability of Staphylococcus aureus to invade and persist within osteoblasts. Here, we sought to determine whether the metabolic and extracellular organic matrix formation and mineralization ability of S. aureus-infected human osteoblasts can be restored after rifampicin (RMP) therapy.

Methods

The human osteoblast-like Saos-2 cells infected with S. aureus EDCC 5055 strain and treated with 8 µg/ml RMP underwent osteogenic stimulation for up to 21 days. Test groups were Saos-2 cells + S. aureus and Saos-2 cells + S. aureus + 8 µg/ml RMP, and control groups were uninfected untreated Saos-2 cells and uninfected Saos-2 cells + 8 µg/ml RMP.


Bone & Joint Research
Vol. 11, Issue 3 | Pages 143 - 151
1 Mar 2022
Goetz J Keyssner V Hanses F Greimel F Leiß F Schwarz T Springorum H Grifka J Schaumburger J

Aims

Periprosthetic joint infections (PJIs) are rare, but represent a great burden for the patient. In addition, the incidence of methicillin-resistant Staphylococcus aureus (MRSA) is increasing. The aim of this rat experiment was therefore to compare the antibiotics commonly used in the treatment of PJIs caused by MRSA.

Methods

For this purpose, sterilized steel implants were implanted into the femur of 77 rats. The metal devices were inoculated with suspensions of two different MRSA strains. The animals were divided into groups and treated with vancomycin, linezolid, cotrimoxazole, or rifampin as monotherapy, or with combination of antibiotics over a period of 14 days. After a two-day antibiotic-free interval, the implant was explanted, and bone, muscle, and periarticular tissue were microbiologically analyzed.


Bone & Joint Research
Vol. 11, Issue 2 | Pages 73 - 81
22 Feb 2022
Gao T Lin J Wei H Bao B Zhu H Zheng X

Aims

Trained immunity confers non-specific protection against various types of infectious diseases, including bone and joint infection. Platelets are active participants in the immune response to pathogens and foreign substances, but their role in trained immunity remains elusive.

Methods

We first trained the innate immune system of C57BL/6 mice via intravenous injection of two toll-like receptor agonists (zymosan and lipopolysaccharide). Two, four, and eight weeks later, we isolated platelets from immunity-trained and control mice, and then assessed whether immunity training altered platelet releasate. To better understand the role of immunity-trained platelets in bone and joint infection development, we transfused platelets from immunity-trained mice into naïve mice, and then challenged the recipient mice with Staphylococcus aureus or Escherichia coli.


Bone & Joint Research
Vol. 11, Issue 2 | Pages 49 - 60
1 Feb 2022
Li J Wong RMY Chung YL Leung SSY Chow SK Ip M Cheung W

Aims

With the ageing population, fragility fractures have become one of the most common conditions. The objective of this study was to investigate whether microbiological outcomes and fracture-healing in osteoporotic bone is worse than normal bone with fracture-related infection (FRI).

Methods

A total of 120 six-month-old Sprague-Dawley (SD) rats were randomized to six groups: Sham, sham + infection (Sham-Inf), sham with infection + antibiotics (Sham-Inf-A), ovariectomized (OVX), OVX + infection (OVX-Inf), and OVX + infection + antibiotics (OVX-Inf-A). Open femoral diaphysis fractures with Kirschner wire fixation were performed. Staphylococcus aureus at 4 × 104 colony-forming units (CFU)/ml was inoculated. Rats were euthanized at four and eight weeks post-surgery. Radiography, micro-CT, haematoxylin-eosin, mechanical testing, immunohistochemistry (IHC), gram staining, agar plating, crystal violet staining, and scanning electron microscopy were performed.


Bone & Joint Research
Vol. 10, Issue 7 | Pages 380 - 387
5 Jul 2021
Shen J Sun D Fu J Wang S Wang X Xie Z

Aims

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.

Methods

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.


Bone & Joint Research
Vol. 10, Issue 3 | Pages 218 - 225
1 Mar 2021
Wiesli MG Kaiser J Gautier E Wick P Maniura-Weber K Rottmar M Wahl P

Aims

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.

Methods

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.