Prosthetic joint infection is one of the most challenging complications of joint alloplasty and the diagnosis remains difficult. The aim of the study was to investigate the bacterial flora in surgical samples from 22 prosthetic patients using a panel of culture-independent molecular methods including broad range 16S rRNA gene PCR, cloning, sequencing, phylogeny, quantitative PCR (qPCR), and fluorescence in situ hybridization (FISH). Concomitant samples were cultured by standard methods. Molecular methods detected presence of bacteria in samples from 12 of 22 patients. Using clone libraries a total of 40 different bacterial species were identified including known pathogens and species not previously described in association with prosthetic joint infections. The predominant species were Propionibacterium acnes and Staphylococcus epidermidis; polymicrobial infections were found in 9 patients. Culture-based methods showed bacterial growth in 8 cases with the predominant species being S. epidermidis. Neither anaerobic bacteria (including P. acnes) nor any of the species not previously described in implant infections were isolated. Additionally, 7 of the 8 culture positive cases were monomicrobial. Overall, the results of culture-based and molecular methods showed concordance in 11 cases (hereof 9 negative by both methods) and discrepancy in 6 cases. In the remaining 5 cases, culture-based methods identified only one species or a group of bacteria (e.g., coagulase negative staphylococci or coryneform rods), while culture-independent molecular methods were able to detect several distinct bacterial species including a species within the group identified by culture. A qPCR assay was developed to assess the abundance of Propionibacterium while S. aureus was quantified by a published S. aureus qPCR assay. These quantifications confirmed the findings from the clone library approach and showed the potential of qPCR for fast detection of bacteria in orthopedic samples. Additionally, both single cells and microcolonies were visualized using FISH and confocal scanning laser microscopy. In conclusion, the molecular methods detected a more diverse bacterial flora in prosthetic joint infections than revealed by standard culture-based methods, and polymicrobial infections were more frequently observed. The pathogenesis of these microorganisms and their role in implant-associated infections needs to be determined

Introduction. Degenerative disc disease results from mechanical alteration of the intervertebral disc. Biochemical modifications of the nucleus matrix are also incriminated. Furthermore, genetic predispositions as well as vascular factors have been advocated in the process of disc degeneration. A relationship between sciatica and Propionibacterium acnes has been described. However, it remains unclear if the hypothesis of a subclinical spondylodiscitis might play a role in the pathophysiology of degenerative disc disease. The purpose of this study was to analyze the possible presence of bacteria in lumbar discs of patients with degenerative disc disease. Methods. We prospectively analyzed the presence of bacteria in 83 patients (34 males and 49 females, average age 41 years) treated by lumbar disc replacement at L3-L4, L4-L5 or L5-S1. An intraoperative biopsy and microbiological culture were performed for each disc to determine if intradiscal bacteria were present. Great care was taken to avoid any source of contamination during the conditioning process of the biopsy. Microbiological results were compared to the magnetic resonance stages of disc degeneration according to the Pfirrmann and Modic classifications. Possible sources of previous iatrogenic disc contamination after discography or nucleotomy were analyzed. Results. The magnetic resonance stages were Pfirrmann IV or V, with Modic I signs in 32 and Modic II in 25 cases. A preoperative discography was performed in 49 patients, and 24 had previous nucleotomy. Germs were found in 40 discs, 43 cultures were steriles. The following bacteria were evidenced: Propionibacterium acnes 18, Staphylococcus coagulase negative 16, Staphylococcus aureus 3, Gram negative bacilli 3, Micrococcus 3, Corynebacterium 3, others 5. Ten biopsies presented several different germs. Bacteria were predominantly found in males (p=0.012). The mostly positive level was L4-L5 (p=0.075). Histological examination of 31 discs found inflammatory cells in 33 % of the biopsies with positive bacterial culture, versus 5 % of the sterile biopsies (p=0.038). There was no significant relationship between bacterial evidence and Modic sign. A preoperative discography or previous nucleotomies did not represent significant contamination sources. None of the patients presented clinical signs of infection. Conclusions. The finding of bacteria in 48 % of disc biopsies, presence of inflammatory cells at histological examination, the absence of responsibility of the discography as a factor of contamination, and the absence of clinical post-operative infection, defend the hypothesis of a low-grade spondylodiscitis which might play a role in the pathophysiology of degenerative disc disease. On the other hand, the presence of skin commensal bacteria, of ¼ of polymicrobial biopsies, and the fact that previous nucleotomy doesn't seem to be involved in inoculation, cannot allow to eliminate a contamination of the samples. Further studies are necessary to elucidate the responsability of intradiscal bacteria in degenerative disc disease. This could influence our treatment strategy of back pain, which could be based in the future on antibiotics

Introduction. Despite the routine use of irrigation, debridement and systemic antibiotics, there is a high incidence of infection in severe open fractures. The synergistic use of local and systemic antibiotics appreciably reduces infection rates although the time window within which this is effective is unknown. The aim was to determine if delaying treatment of wounds causes higher levels of infection. Methods. A defect was created in the femurs of 90 Sprague-Dawley rats and inoculated with 105CFUs Staphylococcus aureus. At 2, 6 and 24 hours following contamination, the defect was irrigated and debrided. The experimental groups had either vancomycin or tobramycin impregnated PMMA beads placed within the segmental defect. The controls received no further treatment. Two weeks after wound closure, the bacteria within the femur were quantified. Results. Delaying irrigation and debridement resulted in significantly more bacteria (p<0.01) within the control group (2 hr < 6 hr <24 hr). Both locally delivered tobramycin and vancomycin significantly reduced the bacteria (p<0.05) when administered at the earlier time points (2 and 6 hours). Locally-delivered antibiotics were ineffective when delivered at 24 hours. Conclusion. Delaying treatment of contaminated defects reduces its effectiveness to eradicate infection. This is presumably because of the biofilm formation by the bacteria. Biofilms begin to form within a couple of hours and are mature within 12 hours. Early treatment of the wound allows the surgeon to physically remove the bacteria or have antibiotics present before a mature biofilm protects the bacteria

Most animal studies indicate that early irrigation and debridement reduce infection after an open fracture. Unfortunately, these studies often do not involve antibiotics. Clinical studies indicate that the timing of initial debridement does not affect the rate of infection but these studies are observational and fraught with confounding variables. The purpose of this study was to control these variables using an animal model incorporating systemic antibiotics and surgical treatment. We used a rat femur model with a defect which was contaminated with Staphylococcus aureus and treated with a three-day course of systemic cefazolin (5 mg/kg 12-hourly) and debridement and irrigation, both of which were initiated independently at two, six and 24 hour time points. After 14 days the bone and hardware were harvested for separate microbiological analysis. No animal that received antibiotics and surgery two hours after injury had detectable bacteria. When antibiotics were started at two hours, a delay in surgical treatment from two to six hours significantly increased the development of infection (p = 0.047). However, delaying surgery to 24 hours increase the rate of infection, but not significantly (p = 0.054). The timing of antibiotics had a more significant effect on the proportion of positive samples than earlier surgery. Delaying antibiotics to six or 24 hours had a profoundly detrimental effect on the infection rate regardless of the timing of surgery. These findings are consistent with the concept that bacteria progress from a vulnerable planktonic form to a treatment-resistant biofilm

Aims. The aim of this study was to evaluate the diagnostic value of preoperative serum CRP, white blood cell count (WBC), percentage of neutrophils (%N), and neutrophil to lymphocyte ratio (NLR) when using the fracture-related infection (FRI) consensus definition. Methods. A cohort of 106 patients having surgery for suspected septic nonunion after failed fracture fixation were studied. Blood samples were collected preoperatively, and the concentration of serum CRP, WBC, and differential cell count were analyzed. The areas under the curve (AUCs) of diagnostic tests were compared using the z-test. Regression trees were constructed and internally cross-validated to derive a simple diagnostic decision tree. Results. Using the FRI consensus definition, 46 patients (43%) were identified as infected. Sensitivity, specificity, and AUC of CRP were 67% (95% confidence interval (CI) 52% to 80%), 61% (95% CI 47% to 74%), and 0.64 (95% CI 0.54 to 0.74); of WBC count were 17% (95% CI 9% to 31%), 95% (95% CI 86% to 99%), and 0.57 (95% CI 0.50 to 0.62); of %N 13% (95% CI 6% to 26%), 87% (95% CI 76% to 93%), and 0.50 (95% CI 0.43 to 0.56); and of NLR 28% (95% CI 17% to 43%), 80% (95% CI 68% to 88%), and 0.54 (95% CI 0.46 to 0.63), respectively. A better performance of serum CRP was shown in comparison to the leucocyte count (p = 0.006), %N (p < 0.001), and NLR (p = 0.001). A statistically lower serum CRP level was shown in patients with an infection caused by a low virulence microorganism in comparison to high virulence bacteria (p = 0.008). We found that a simple decision tree approach using only low serum neutrophils (< 3.615 × 10. 9. /l) and low CRP (< 2.45 mg/l) may allow better identification of aseptic cases. Conclusion. The evaluated serum inflammatory markers showed limited diagnostic value in the preoperative diagnosis of FRI when using the uniform FRI Consensus Definition. Therefore, they should remain as suggestive criteria in diagnosing FRI. Although CRP showed a higher performance in comparison to the other serum markers, it is insufficiently accurate to diagnose a septic nonunion, especially when caused by low virulence microorganisms. Cite this article: Bone Joint J 2020;102-B(7):904–911

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This study aimed to investigate the clinical characteristics and outcomes associated with culture-negative limb osteomyelitis patients.

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Musculoskeletal infection is a devastating complication in both trauma and elective orthopaedic surgeries that can result in significant morbidity. Aim of this study was to assess the effectiveness and complications of local antibiotic impregnated dissolvable synthetic calcium sulphate beads (Stimulan Rapid Cure) in the hands of different surgeons from multiple centres in surgically managed bone and joint infections.

Systemic antibiotics reduce infection in open fractures. Local delivery of antibiotics can provide higher doses to wounds without toxic systemic effects. This study investigated the effect on infection of combining systemic with local antibiotics via polymethylmethacrylate (PMMA) beads or gel delivery. An established Staphylococcus aureus contaminated fracture model in rats was used. Wounds were debrided and irrigated six hours after contamination and animals assigned to one of three groups, all of which received systemic antibiotics. One group had local delivery via antibiotic gel, another PMMA beads and the control group received no local antibiotics. After two weeks, bacterial levels were quantified. . Combined local and systemic antibiotics were superior to systemic antibiotics alone at reducing the quantity of bacteria recoverable from each group (p = 0.002 for gel; p = 0.032 for beads). There was no difference in the bacterial counts between bead and gel delivery (p = 0.62). . These results suggest that local antibiotics augment the antimicrobial effect of systemic antibiotics. Although no significant difference was found between vehicles, gel delivery offers technical advantages with its biodegradable nature, ability to conform to wound shape and to deliver increased doses. Further study is required to see if the gel delivery system has a clinical role. Cite this article: Bone Joint J 2015;97-B:1423–7

Antimicrobial resistance (AMR) is projected to result in 10 million deaths every year globally by 2050. Without urgent action, routine orthopaedic operations could become high risk and musculoskeletal infections incurable in a “post-antibiotic era.” However, current methods of studying AMR processes including bacterial biofilm formation are 2D in nature, and therefore unable to recapitulate the 3D processes within in vivo infection. Within this study, 3D printing was applied for the first time alongside a custom-developed bioink to bioprint 3D bacterial biofilm constructs from clinically relevant species including Staphylococcus aureus (MSSA), Methicillin-resistant staphylococcus aureus (MRSA), Escherichia coli and Pseudomonas aeruginosa. Bacterial viability and biofilm formation in bioprinted constructs was excellent, with confocal laser scanning microscopy (CSLM) used to demonstrate biofilm production and maturation over 28 days. Bioprinted 3D MRSA and MSSA biofilm constructs had greater resistance to antimicrobials than corresponding two-dimensional (2D) cultures. Thicker 3D E.coli biofilms had greater resistance to tetracycline than thinner constructs over 7 days of treatment. Raman spectroscopy was also adapted in a novel approach to non-invasively diagnose 3D bioprinted biofilm constructs located within a joint replacement model. In conclusion, mature bacterial biofilm constructs were reproducibly 3D bioprinted for the first time using clinically relevant bacteria. This methodology allows the study of antimicrobial biofilm penetration in 3D, and potentially aids future antimicrobial research, replicating joint infection more closely than current 2D culture models. Furthermore, by deploying Raman spectroscopy in a novel fashion, it was possible to diagnose 3D bioprinted biofilm infections within a joint replacement model

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The Open-Fracture Patient Evaluation Nationwide (OPEN) study was performed to provide clarity in open fracture management previously skewed by small, specialist centre studies and large, unfocused registry investigations. We report the current management metrics of open fractures across the UK.

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The aim of the present study was to assess the outcomes of the induced membrane technique (IMT) for the management of infected segmental bone defects, and to analyze predictive factors associated with unfavourable outcomes.

Background. Previous data from our institution show that more than half of all prosthetic joint infections are due to S. aureus. A significant proportion of these bacteria may have an endogenous source. Detecting and treating asymptomatic S. aureus nasal carriers preoperatively has been shown to reduce the risk of infection. Material and Methods. This is an ongoing prospective study that started in March/2009 and involves primary total knee or hip arthroplasties candidates. So far preoperative nasal swab cultures were performed in 211(61%) out of 347 patients operated until April/2010. Carriers are identified and randomly chosen for preoperative treatment consisting of nasal mupirocin twice a day and daily cloro-hexidine baths in the 5 days that precede surgery. Antibiotic prophylaxis is cefazolin 24hours adding a single vancomycin dose in MRSA carriers. Results. Around 30% (64/211) of patients presented Saureus nasal carriage and 6 of them (9.4%) were methicilin-resistant. Infection rate was lower in the non-carriers: 1.36% (2/147). The group of 33 untreated carriers so far has the higher prevalence of infection (6.06%; Odds ratio=4.677; p=0.098). In the 31 treated carriers there was only one infection to date (3.23%; Odds ratio=2.371; p=0.463). The 136 patients control group in which no preoperative nasal culture was made registered 4 infections (2.94%; Odds ratio=2.197; p=0.356). Five out of the nine infections involved S. aureus. We further isolated 3 S. epidermidis, 1 enterococcus and 2 gram-negatives. Discussion. It seems that two S. aureus infections were due to endogenous contamination as the infecting bacteria possesses the exact same phenotype as the colonizing preoperative one (one untreated and one treated carrier). In other two S. aureus cases the seeding appears exogenous (a preoperative negative culture and a infecting bacteria different than the preoperative screening). One infection was registered in a non-studied patient. Accordingly, exogenous contamination seems responsible for at least 6 out of 9 infections. Conclusion. These preliminary results suggest that S. aureus colonization may be an endogenous risk factor for prosthetic joint infection that can be influenced. However exogenous contamination is still a major risk factor in our institution

Staphylococcus aureus is responsible for 60–70% infections of surgical implants and prostheses in Orthopaedic surgery, costing the NHS £120–200 million per annum. Its ability to develop resistance or tolerance to a diverse range of antimicrobial compounds, threatens to halt routine elective implant surgery. One strategy to overcome this problem is to look beyond traditional antimicrobial drug therapies and investigate other treatment modalities. Biophysical modalities, such as ultrasound, are poorly explored, but preliminary work has shown potential benefit, especially when combined with existing antibiotics. Using a methicillin-sensitive S. aureus reference strain and the dissolvable bead assay, biofilms were challenged by a low-intensity ultrasound (1.5MHz, 30mW/cm2, pulse duration 200µs/1KHz) for 20 minutes and gentamicin. The outcome measures were colony-forming units/mL (CFU/mL) and the minimum biofilm eradication concentration (MBEC) of gentamicin. The mean number of S. aureus within control biofilms was 1.04 × 109 CFU/mL. There was no clinically or statistically significant (p=0.531) reduction in viable S. aureus following ultrasound therapy alone. The MBEC of gentamicin for this S. aureus strain was 256 mg/L. The MBEC of gentamicin with the addition of ultrasound was 64mg/L. Further studies confirmed that the mechanism of action was due to incomplete disruption of the extracellular matrix with subsequent metabolic stimulation of the dormant biofilm-associated bacteria due to increased nutrient availability and oxygen tension. Low intensity pulsed ultrasound was associated with a 4-fold reduction in the effective biofilm eradication concentration of gentamicin; bringing the MBEC of gentamicin to within clinically achievable concentrations

Infection rates following arthroplasty surgery are between 1–4%, with higher rates in revision surgery. The associated costs of treating infected arthroplasty cases are considerable, with significantly worse functional outcomes reported. New methods of infection prevention are required. HINS-light is a novel blue light inactivation technology which kills bacteria through a photodynamic process. The aim of this study was to investigate the efficacy of HINS-light for the inactivation of bacteria isolated from infected arthoplasty cases. Specimens from hip and knee arthroplasty infections are routinely collected to identify causative organisms. This study tested a range of these isolates for sensitivity to HINS-light. During testing, bacterial suspensions were exposed to increasing doses of HINS-light of (123mW/cm2 irradiance). Non-light exposed control samples were also set-up. Bacterial samples were then plated onto agar plates and incubated at 37°C for 24 hours before enumeration. Complete inactivation was achieved for all Gram positive and negative microorganisms More than a 4-log reduction in Staphylococcus epidermidis and Staphylococcus aureus populations were achieved after exposure to HINS-light for doses of 48 and 55 J/cm2, respectively. Current investigations using Escherichia coli and Klebsiella pneumoniae show that gram-negative organisms are also susceptible, though higher doses are required. This study has demonstrated that HINS-light successfully inactivated all clinical isolates from infected arthroplasty cases. As HINS-light utilises visible-light wavelengths it can be safely used in the presence of patients and staff. This unique feature could lead to possible applications such as use as an infection prevention tool during surgery and post-operative dressing changes

Aim. Previous studies of primary internal fixation of infected non-unions have reported high failure rates. Local antibiotic carriers and coatings have been advocated to reduce infection around implants and allow bone healing. We evaluated the effect of a calcium sulphate/hydroxyapatite antibiotic-loaded composite on bone healing and the eradication of infection in combination with internal fixation. Method. Twelve cases of established infected non-union, with segmental bone loss of up to 1cm were treated using a multidisciplinary protocol. This included; excision, deep sampling, stabilisation, local and systemic antibiotics, and soft-tissue closure. We treated 5 femurs, 4 humeri, 1 tibia and 2 periarticular non-unions at the ankle. Mean age was 59.8 years (34–75) and 9 patients had systemic co-morbidities (C-M Type B hosts). 9 patients had single stage surgery, with 5 IM Nails and 4 plates. Three patients had planned second stage internal fixation after external fixation to correct deformity. Staph. aureus was the commonest pathogen (5 cases) with polymicrobial infection in 3 cases. Results. All 12 patients were infection-free at a mean follow-up of 23 months (range 13–34 months). Union was achieved in 11/12 (92%) with the primary surgery alone. The single failure was the tibial case, who remains with an infection-free, stiff non-union. Conclusion. This protocol offered good results, mainly with a single stage treatment. Primary internal fixation was possible in 9 cases, without recurrent infection. The combination of excision of infected dead bone and a high level of local antibiotics above the Minimum Inhibitory Concentration and Minimum Biofilm Eradication Concentration levels for common bacteria, allowed a high success rate in these difficult cases

In some centres, serial bedside aspirations, in association with intravenous antibiotics, are still an accepted treatment for septic arthritis (Mathews, Postgraduate Medical Journal, 2008). However, there is a risk that bacterial products remain in the joint, even when the bacteria have been destroyed. We have conducted a study to ascertain whether bacterial products alone have an effect on in situ chondrocyte viability. A hip aspirate (25μl), containing Staphylococcus aureus, from a patient with septic arthritis was added to 5ml culture medium and incubated (37°C) for 48hrs. The solution was then centrifuged (3400g for 10mins) and the supernatant removed. Cartilage explants were harvested from a bovine metacarpophalangeal joint, placed into the bacterial supernatant and incubated at 37°C. Explants were removed at hourly intervals over a 6-hour period and stained with the fluorescent probes chloromethylfluorescein di-acetate (10μM) and propidium iodide (10μM) to label living chondrocytes green and dead cells red respectively. Following imaging of cartilage by confocal microscopy, the percentage cell death at each time point was obtained using Volocity 4 software. Chondrocyte death increased markedly with time: 0.04% at 2hrs, 28% at 4hrs and 39% at 6hrs. This study shows that bacterial products rapidly penetrate the cartilage matrix and have a damaging effect on in situ chondrocyte viability. Further work will clarify the contributions made by the various toxic components in the culture supernatant, but these data support the need to remove the bacteria and their products aggressively as part of the treatment of septic arthritis

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Deep surgical site infection (SSI) is common after lower limb fracture. We compared the diagnosis of deep SSI using alternative methods of data collection and examined the agreement of clinical photography and in-person clinical assessment by the Centers for Disease Control and Prevention (CDC) criteria after lower limb fracture surgery.

Background. Both from experimental studies and the large arthroplasty registries there is evidence that bacteria are more often involved in implant loosening then is currently reported. To further elucidate this potential problem, the current study investigated the hypothesis that many total hip arthroplasty revisions, classified as aseptic, are in fact low-grade infections missed with routine diagnostics. Methods. In 7 Dutch hospitals, 176 patients with the preoperative diagnosis of aseptic loosening of their total hip arthroplasty were enrolled. From each patient, the preoperative history was obtained. During surgery, between 14 and 20 tissue samples were obtained for routine culture, pathology analysis and broad range 16S rRNA PCR with reverse line blot hybridization (PCR-RLB). Samples were taken from the (neo-) capsule and acetabular and femoral interface tissue. Cultures were performed locally according to similar protocols. One specialized pathologist, blinded for all other results, analyzed all pathology samples. The PCR-RLB analysis was performed centrally, using a technique previously validated for orthopedic use. Patients were classified as not infected, suspect for infection or infected, according to strict, predefined criteria. Each patient had a follow-up visit after 1 year. Results. Seven patients were classified as infected, of whom 4 were not identified by routine culture. In these patients, positive PCR-RLB results were supported by pathology analyses suspect for infection as well. An additional 15 patients were suspect for infection as well. The microorganisms identified were low virulent bacteria, like coagulase negative staphylococci and Proprionibacterium acnes, in most cases. Twenty of these 22 patients received a cemented prosthesis, fixated with antibiotic-loaded bone cement. All patients received prophylactic systemic antibiotics, after obtaining the tissue samples. Seven of the 22 patients reported complaints one year post-surgery, only one showing signs of early loosening. However, in none of the patients additional surgery was performed. Discussion. Although percentages were not as high as previously reported in literature, between 4 and 13 percent of patients with the preoperative diagnosis of aseptic loosening were infected. However, as thorough debridement was performed during surgery and prophylactic antibiotics were used, it did not have many clinical consequences, as most patients performed well at the 1-year follow-up. Whether it has implications for long-term implant survival remains to be seen

Aims. Currently, the most common approach for the management of a chronic PJI is a Two-Stage Replacement; because of success rates exceeding 90% when using an antibiotic impregnated cement spacer. Reliable information regarding the etiologic microorganism and its sensitivities is essential to select the antimicrobial therapy that should be used locally in the bone cement spacer during the first stage surgery as well as to select the appropriate microbiological systemic agent. Diagnostic algorithms focus to the importance of joint aspiration cultures although in the modern literature, preoperative joint aspiration has a broad range of values of sensitivity and the proportion of “dry-aspirations” is not well assessed. This low sensitivity of aspiration fluid samples in chronic-PJI is partly attributable to the fact that the majority of the microorganisms in these infections grow in biofilms attached to the implant. We have developed this biopsy technique in an effort to improve the identification rates of the causative organism. Materials and methods. A sample is harvested through a 4 mm bone trephine and the target is the bone-prosthesis gap. We have compared the results of preoperative PIB with the results of cultures from intra-operative tissue collected during the first stage surgery. In both cases a prolonged culture protocol (10 days) in enrichment media was used. On the basis of this relation, sensitivity, specificity, positive and negative predictive values and accuracy were calculated. Results. Twenty-four PIB were done on the 24 patients (10 hips and 14 knees) who subsequently underwent two-stage revision surgery because of high suspicion of PJI between January 2007 and December 2009. A retrospective analysis was performed in these 24 patients (13 women and 11 men) in the mean age of 70 years (from 63 to 88 years old). Nineteen of the cases were primary and 5 were revision arthroplasty. Nineteen patients (79%) were positive for infection from operative tissue cultures. The sensitivity was 0.79 (95% CI, 0.54–0.93); the specificity was 0.80 (95% CI, 0,30–0.99), the positive predictive value was 0.94 (95% CI, 0.67–0.99), the negative predictive value was 0.50 (95% CI, 17.5–82.5) and the accuracy was 0.79. Conclusion. PIB is a useful test to, preoperatively, isolate the infecting bacteria. The values of sensitivity, specificity and accuracy are on the average of the currently published with joint aspiration or biopsy samples cultures. Although comparative study is necessary we believe that the PIB could be useful in cases with high suspicion of PJI and negative joint aspiration cultures and in cases where no fluid is aspired from the joint, in order to preoperatively isolate the infecting bacteria

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Deep surgical site infection (SSI) remains an unsolved problem after hip fracture. Debridement, antibiotic, and implant retention (DAIR) has become a mainstream treatment in elective periprosthetic joint infection; however, evidence for DAIR after infected hip hemiarthroplaty is limited.