Orthopaedic and trauma implant related infection remains one of the major complications that negatively impact clinical outcome and significantly increase healthcare expenditure. Hydroxyapatite has been used for many years to increase implant osseointegration. Silver has been introduced into hydroxyapatite as an antimicrobial coating for orthopedic implants. This surface coatings can both increase tissue compatibility and prevent implant-related infections. We examined infection markers and blood silver values, liver and kidney function tests of 30 patients with of three groups of orthopedic implants, external fixators, intramedullary nails and hip replacements, coated with Ag + ion doped CaP based ceramic powder to determine safety and effectiveness of this dual-function coating. During 1 year follow-up, the pin sites were observed at the external fixator group, and wound areas for the proximal femoral nail and hip arthroplasty group at regular intervals. In addition, liver and kidney function tests, infection markers and blood silver values were checked in patients. In the external fixator group, only 4 out of 91 pin sites (%4.39) were infected. The wound areas healed without any problem in patients with proximal femoral nails and hip arthroplasty. There was no side effect suggesting silver toxicity such as systemic toxic side effect or argyria in any patient and blood silver level did not increase. Compared to similar patient groups in the literature, much lower infection rates were obtained (p = 0.001), and implant osseointegration was good. In patients with chronic infection, the implants were applied acutely after removing the primary implant and with simple debridement. Unlike other silver coating methods, silver was trapped in hydroxyapatite crystals in the ionic form, which is released from the coating during the process of osseointegration, thus, the silver was released into the systemic circulation gradually that showed antibacterial activity locally. We conclude that the use of orthopedic implants with a silver ion added calcium phosphate-based special coating is a safe method to prevent the implant-related infection. This work was supported by TUBİTAK Project Number 315S101

Aim. A novel anti-infective biopolymer implant coating was developed to prevent bacterial biofilm formation and allow on-demand burst release of anti-infective silver (Ag) into the surrounding of the implant at any time after surgery via focused high-energy extracorporeal shock waves (fhESW). Method. A semi-crystalline Poly-L-lactic acid (PLLA) was loaded with homogeneously dissolved silver (Ag) applied onto Ti6Al4V discs. A fibroblast WST-1 assay was performed to ensure adequate biocompatibility of the Ag concentration at 6%. The prevention of early biofilm formation was investigated in a biofilm model with Staphylococcus epidermidis RP62A after incubation for 24 hours via quantitative bacteriology. In addition, the effect of released Ag after fhESW (Storz DUOLITH SD1: 4000 impulses, 1,24 mJ/mm. 2. , 3Hz, 162J) was assessed via optical density of bacterial cultures (Escherichia coli TG1, Staphylococcus epidermidis RP62A, Staphylococcus aureus 6850) and compared to an established electroplated silver coating. The amount of released Ag after the application of different intensities of fhESW was measured and compared to a control group without fhESW via graphite furnace atomic absorption spectrometry (GF-AAS), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Results. The coating with 6% Ag reduced Staphylococcus epidermidis biofilm formation by 99.7% (mean±SD: 2.1×10^5 ± 3,9×10^5 CFU/µL) compared to uncoated controls (6.8×10^7 ± 4.9×10^7 CFU/µL); (p=0.0001). After applying fhESW the commercially available electroplated silver coating did not prevent the growth of all tested bacterial strains. Bacterial growth is delayed with 4% Ag and completely inhibited with 6% Ag in the novel coating, except for a small increase of S. aureus after 17 hours. SEM and EDS confirmed a local disruption of the coating after fhESW. Conclusions. This novel anti-infective implant coating has the potential to prevent bacterial biofilm formation. The on-demand burst release of silver via fhESW could be an adjunctive in the treatment of implant related infection and is of particular interest in the concept of single stage revision surgery

Introduction. Fracture related infections (FRI) following intramedullary nailing for tibial shaft fractures remain challenging to treat with associated high patient morbidity and healthcare costs. Recently, antibiotic-coated nails have been introduced as a strategy to reduce implant related infection rates in high-risk patients. We present the largest single-centre case series on ETN PROtect® outcomes reporting on fracture union, infection rates and treatment complications. Materials and Methods. 56 adult patients underwent surgery with ETN PROtect® between 01/09/17 and 31/12/20. Indications consisted of acute open fractures and complex revision cases (FRI, non-union surgery and re-fracture) with a mean of 3 prior surgical interventions. 51 patients had an open fracture as their index injury. We report on patient characteristics and outcomes including radiological/clinical union and deep infection. The one-year minimum follow-up rate was 87.5%. Results. One (1.8%) patient developed a deep surgical infection and associated non-union requiring further surgery. In addition, we identified three cases (5.4%) of aseptic non-union following facture treatment with ETN PROtect®. Of the 5 patients who underwent staged complex revision surgery for established FRI with ETN PROtect®, all had treatment failure with ongoing symptoms of deep infection requiring further treatment. Conclusions. Use of the ETN PROtect® nail in high-risk patients in the acute trauma setting demonstrates promising outcomes in the prevention of implant-related infection. In our limited series we have failed to observe any benefit over uncoated nails, when used in treating cases of established FRI/osteomyelitis and would therefore advise caution in their use, especially in view of the high cost

Aim. Staphylococcus aureus bacteremia (SAB) is associated with significant morbidity and mortality, 20–30 % risk of infection in patient with implant related infection (IRI) .18F-FDG PET/CT is helpful in the management of SAB, leading to detection of more metastatic foci and treatment modification and finally decrease relapses and mortality rate. Our objective was to analyze mortality in high risk SAB patients undergoing 18F-FDG PET/CT and to see whether it's use in patients with IRI reduced their mortality. Method. We performed a retrospective study at a university hospital in Belgium. All cases of high risk adult SAB between January 2014 and June 2017 were reviewed. We collected the clinical characteristics including presence of metastatic foci on 18F-FDG PET/ CT, mortality at 1 year. Results. A total of 102 patients were included. Twenty-one patient with IRI were identified (20.6%). In 94.1 % (N=96) SAB were due to methicillin-sensitive staphylococcus aureus (MSSA). 18F-FDG PET/ CT was performed in 47% (N =48) of patients and a metastatic foci was identified in 45.8% of cases (N=22/48). The detection of metastatic foci lead to surgical intervention in a site other than the site of IRI in 38% versus 14% (P < 0.001) in patients undergoing or not 18F-FDG PET/CT respectively. The overall mortality rate was 31.3 % (32/102). The mortality rate was 16.6% (8 /48) and 41.3 % (24/54) in patients undergoing or not 18F-FDG PET/ CT respectively (P=0.03). For IRI, the overall mortality was 9.3 % versus 15.6% in patients undergoing or not 18F-FDG PET/ CT respectively (P<0.001). There was a significant difference in mortality rate at 30 (P=0.001), 90 days (P–0.01) and one year (P–0.004) between patients undergoing or not 18F-FDG PET/ CT respectively. In bivariate analysis, the overall, 30, 90 days and one year mortality rate was significantly reduced among patient with kidney failure (P< 0.001), diabetic foot infection (P=0.006), age >70 years (P=0.007) and prosthetic joint or plate infection (P< 0.001) in whom the 18F-FDG PET/ CT was performed. Conclusions. Mortality rate was reduced in high risk SAB patients undergoing 18F-FDG PET/ CT. The use of 18F-FDG PET/CT reduced mortality in patients with PJI by detecting more metastatic site leading to more aggressive treatment

Summary. Staphylococcus aureus isolates from Fracture fixation device related infections contained fewer isolates that form a strong biofilm in comparison with isolates from Prosthetic joint infections. Both orthopaedic implant related infection groups possessed fnbB and sdrE more frequently than the non-implant related infection groups. Introduction. One of the most common pathogen causing musculoskeletal infections is Staphylococcus aureus. The aim was to characterise S. aureus isolated from these infections and to look for differences between the isolates from orthopaedic implant related infections (OIRI) and those in non-implant related infections (NIRI). The OIRI are further differentiated in those associated with fracture fixation (FFI) devices and those found in prosthetic joint infections (PJI). Methods. Three-hundred and five S. aureus isolates were collected from different Swiss and French hospitals (FFI, n=112; PJI, n=105; NIRI, n=88). The cases of NIRI were composed of 27 osteomyelitis (OM), 23 diabetic foot infections (DFI), 27 soft tissue infections (STI) and 11 postoperative spinal infections (SI). Isolates were tested for their ability to form a biofilm. They were typed by agr (accessory gene regulator) group and genes coding for the 13 most relevant MSCRAMMs, Panton-Valentine leukocidin (PVL), PIA (polysaccharide intercellular adhesin), γ-haemolysin, the five most relevant Staphylococcal enterotoxins (SEA-SEE), exfoliative toxins A and B (ETA and ETB) and toxic shock protein (TST) were screened for by PCR. Results. The majority of the S. aureus isolates were methicillin susceptible (MSSA) with 83.4% for the OIRI and 93.2% for the NIRI. All isolates were able to produce a biofilm. A strong biofilm was produced in 13.8% of the OIRI isolates compared to 10.2% of the NIRI isolates. The difference between the isolates of the PJI versus the FFI was statistically significant (20% vs 8%; p=0.011). All four agr types were present in all groups. agrI predominated in the OIRI (42.4%) as well as in the NIRI (44.4%). Comparing OIRI with NIRI, agrII was present in a higher prevalence in OIRI (30.9% vs 14.8%) and agrIII in a lower incidence (21.2% vs 30.7%). Genes cna, clfA and bbp were exhibited predominantly by isolates from the NIRI, while the fnbB and the sdrE gene were more frequently observed among OIRI. Conclusions. Methicillin susceptible S. aureus (MSSA) was more prevalent than methicillin resistant S. aureus (MRSA) in this collection. Possible trends for the orthopaedic device associated infection groups FFI and PJI could be observed whereby isolates from PJI produced stronger biofilm than isolates from the FFI group. The agr type agrII, the fnbB gene and sdrE gene were more prevalent present in the OIRI compared to the NIRI. In contrast, agrIII, and the bbp gene were more prevalent in the NIRI than in the OIRI

The field of nanoparticle related research for the diagnosis and therapy of diseases evolves rapidly. Magnetic nanoparticles in combination with magnetizable implant materials for the treatment of implant related infections present a possible implementation in orthopedics. Magnetic nanoporous silica nanoparticles (MNPSNPs) were developed and equipped with fluorescent dyes. In vitro/in vivo biocompatibility and in vivo biodistribution were examined to appraise their potential applicability. Cell culture tests with NIH-3T3 and HepG2 cell lines indicated a good in vitro biocompatibility. Ferritic and titanium alloy (control) plates were implanted subcutaneously at the hind legs of Balb/c mice. Immediately after i.v. or s.c. injection of MNPSNPs, the caudal half of the mice was placed between the poles of an electro magnet. Exposure to the electromagnetic field of approx. 1.7 T was maintained for 10 minutes. 10 animals each were euthanized at days 0, 1, 7, 21 or 42, respectively. Quantity of MNPSNPs in liver, spleen, kidney, lung and skin/muscle samples was assessed by fluorescent microscopic methods. MNPSNP existence on the implant surface was also appraised after several steps of detachment. MNPSNPs showed a time-dependent accumulation in the organs after i.v. injection with initial accumulation in the lungs followed by redistribution to liver and spleen. After s.c. injection no systemic distribution but local appearance of MNPSNPs could be found. First histological evaluation showed no pathological changes after i.v. injection. With good in vivo biocompatibility, future focus will be laid on increasing circle life time of MNPSNPs and evaluation in an infection model

Background and Purpose. Although the treatment for infected total hip arthroplasty (THA) has been still controversial, some reports suggested two-stage revision THA seems to be more preferable rather than one-stage revision. The purpose of this study is to estimate the outcome of treatment for infected THA in our institutions. Patients and methods. The medical records of patients who have been underwent surgical treatment for infected THA between 2006 and 2012 in two hospitals and followed more than one year after surgery were reviewed. 34 patients and 35 hips were included. Age at surgery, gender, a period until surgical treatment after diagnosis of infection, method of treatment (debridement, one-stage or two-stage revision THA) and the outcome are estimated for each hips. Remission was defined by the absence of local and systemic sign of implant related infection and the normalization of WBC and C-reactive protein value without antibiotics. Result. A mean post-treatment follow-up period was 32.3 months. Two hips were removed without spacer or reconstruction because their general conditions were poor. The remission rates were 22%(2/9) in debridement and retention, 60%(3/5) in one-stage revision THA and 81%(21/26) in two-stage revision THA respectively. Conclusion. The remission rate of two-stage revision was better than one-stage revision in this study. Although our study supports two-stage revision for the treatment of infected THA, the possibility of one-stage revision should not be neglected because the outcome of one-stage revision could be improve in the presence of effective antibiotics and the physical and psychological burden of two-stage revision are serious

Aims

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.

Recent NICE guidelines suggest that Total Hip Arthroplasty (THA) be offered to all patients with a displaced intracapsular neck of femur fracture who: are able to walk independently; not cognitively impaired and are medically fit for the anaesthesia and procedure. This is likely to have significant logistical implications for individual departments. Data from the National Hip Fracture Database was analysed retrospectively between January 2009 and November 2011. The aim was to determine if patients with displaced intracapsular neck of femur fractures admitted to a single tertiary referral orthopaedic trauma unit received a THA if they met NICE criteria. Case notes were then reviewed to obtain outcome and complication rates after surgery. Five hundred and forty-six patients were admitted with a displaced intracapsular neck of femur fracture over the described time period. Sixty-five patients met the NICE criteria to receive a THA (mean age 74 years, M:F = 16: 49); however, 21 patients had a THA. The other patients received either a cemented Thompson or bipolar hemiarthroplasty. Within the THA cohort there were no episodes of dislocation, venous thromboembolism, significant wound complications or infections that required further surgery. Within the hemiarthroplasty cohort there was 2 mortalities, 2 implant related infections, 1 dislocation and 2 required revision to a THA. There is evidence to suggest better outcomes in this cohort of patients, in terms pain and function. There is also a forecasted cost saving for departments, largely due to the relative reduction in complications. However, there were many cases (44) in our department, which would have been eligible for a THA, according to the NICE guidelines, who received a hemiarthroplasty. This is likely a reflection of the increased technical demand, and larger logistical difficulties faced by the department. We did note more complications within the hemiarthroplasty group, however, the numbers are too small to address statistical significance, and a longer follow up would be needed to further evaluate this. There is a clear scope for optimisation and improvement of infrastructure to develop time and resources to cope with the increased demand for THA for displaced intracapsular neck of femur fractures, in order to closely adhere to the NICE guidelines

Based on the analysis of Rittmann and Matter the AO advocated to leave stable implants after osteosynthesis in place and to remove them only when a sufficient bridging of the fractured would have happened. In opposition it generally became accepted to remove instable implants to be replaced by an external fixateur. Using local antiseptics such as Lavasept (Willlenegger) and intravenous antibiotics efficient against the proven bacteria one was able to cure the infection. Additional measures of osteoinduction (mainly cancellous autograft and decortication) favoured bridging of the non-union area. With the help of callus distraction after segmental resection of dead bone areas using more sophisticated external fixateurs marvellous reconstructions of big bone areas became possible. On the other hand we have to realize, that in the upper extremities external fixation is frequently a clumsy installation inhibiting function. Because of delay of union not unfrequently secondary stabilazation of non-union or refracture areas had to be stabilized with secondary internal fixation. This was possible because the infection was already cured. The knowledge of implant related infection did learn us, that the elimination of bacteria linked to a biofilm, which are at rest, frequently are resistant against antibiotics otherwise successful against planctonic bacteria of the same species. Be it by higher concentrations, be it by the use of antibiotics efficient against resting bacteria such as Rifampin ant once other possibilities are developed to be able to treat infections even in presence of internal osteosyntheses. When the success rate of intramedullary nails as they were used by Klemm was distinctly lower compared with external fixateurs at that time, today it becomes possible to us internal fixation in infections with bacteria with a known antibiotic treatment in presence of implants. This opens important doors for the combination of internal fixation, vascular bone grafts and antibiotic treatment accelerating the treatment of infected non-union in adequate cases.Stepwise it became possible to get to better functional results within a shorter time in adequate cases

Background: In recent years an increased trend in MRSA infection has been seen in hospitals and the community, with colonisation rates of between 4 – 17% reported in these patient groups. There is also an association between carriage of Staph. Aureus and staphylococcal surgical wound infection. In our institution there has been concern regarding MRSA surgical site infection and possible cross contamination of elective and emergency patients. There would be implications for implant related infections if this were to occur. This had prompted the unit to consider adopting a screening programme to identify and treat MRSA carriers. This would aim to minimise risk of post operative infection and cross infection. As little was actually known about the MRSA colonisation rates of admissions to our hospital we undertook the following project to assess the feasibility and effectiveness of implementing such a screening programme. Aim: To ascertain the incidence of colonisation with MRSA, rate of wound infection and the associated risk factors in patients admitted to the trauma ward with a fractured neck of femur. Method: A prospective, blinded case series of 100 consecutive patients admitted to the trauma ward with a fractured neck of femur. Three swabs (axilla, nasal and perineum) were taken within 24 hours of admission. Data from each patient was collected to ascertain the presence of risk factors linked to MRSA colonisation and each patient was followed until discharged to assess for surgical site infection. Results: 304 swabs were taken from 100 patients. Age range 60–97. 26% admitted from institutionalised care and 74% admitted from their own home. Four patients were colonised with MRSA on admission (2 nasal, 2 perineal). An association was seen between patients colonised on admission and long term or recent residence in institutionalised care. One of these patients went on to develop colonisation of the surgical wound however this did not lead to surgical site infection and the patient was successfully treated with MRSA eradication therapy only. In these 4 patients all wounds healed satisfactorily with no evidence of infection. There were three superficial surgical site infections postoperatively, all in individuals who were clear on their admission screening. Of these two were due to MRSA and one was due to MSSA. There were no cases of deep infection requiring further surgery. Conclusion:While MRSA continues to be a growing concern we found that, in our hospital, rates of MRSA colonisation and subsequent infection were not high. There were no documented cases of MRSA wound infection in colonised individuals. Given the cost involved in swabbing all patients to detect these low levels of colonisation we do not feel that an expensive screening regimen would be cost effective or justified in our institution