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To provide proof of concept in an in vivo animal model for the prevention of prosthetic joint infection prevention using electric fields along with conventional antibiotic prophylaxis.

Corresponding Author: Marti Bernaus

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To evaluate the efficiency of pulse lavage combined with electrical fields to remove biofilm from a metallic surface.

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The treatment of fracture-related infections (FRI) focuses on obtaining fracture healing and eradicating infection to prevent osteomyelitis. Treatment guidelines include removal, exchange, or retention of the implants used according to the stability of the fracture and the time from the infection. Infection of a fracture in the process of healing with a stable fixation may be treated with implant retention, debridement, and antibiotics. Nonetheless, the retention of an intramedullary nail is a potential risk factor for failure, and it is recommended to exchange or remove the nail. This surgical approach implies additional life-threatening risks in elderly fragile hip fracture patients.

Our study aimed to analyze the results of implant retention for the treatment of infected nails in elderly hip fracture patients.

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Acute post-surgical infection is one of the most serious complications after instrumented thoracolumbar fusion with an incidence of 0.7%-12%. Acute infection can lead to an increase in morbidity, mortality, and economic costs for the healthcare system.

The main objective of our study was to determine the variables associated with a higher risk of acute infection after thoracolumbar instrumentation in our center.

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The purpose of this study is to analyze the demographic and microbiological variables of acute ankle infections posterior to ankle osteosynthesis and to determine the different characteristics of patients withE. cloacae infection.

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To evaluate bacterial adhesion and biofilm formation to metallic cerclage wire versus polymer cerclage system (SuperCable®)

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The effectiveness of mandatory joint aspiration prior to re-implantation in patients with a cement spacer already in place is unclear.

The aim of this study was to evaluate the role of culturing articular fluid obtained by joint aspiration prior to re-implantation in patients who underwent a two stage septic revision.

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In two-stage replacements for septic loosening, some studies have suggested that associate bacterial colonization of spacers had a worse result in relation to the control of the infection and a higher rate of complications after the implantation of the definitive prosthesis.

The aim of our study was to determine the reoperation rate of patients undergoing two-stage revision surgery according to the results of spacer sonication.

Introduction: Although the influence of preoperative nutritional status on short term outcome in arthroplasty is well known, its relationship with early prosthetic joint infection (EPJI) in total knee replacement remains unclear.

Aim: Our aim was to assess the effect of preoperative nutritional status on patients who went on to present with EPJI following total knee replacement surgery. This assessment was based on preoperative blood tests and anthropometric measurements.

Methods: A total of 213 patients undergoing total knee replacement between December 2007 and May 2008 were included in the study. Patients with rheumatoid arthritis were excluded. For each patient we pre-operatively checked haemoglobin level, CRP, ESR, total lymphocyte and protein count, albumin and pre-albumin concentration and triglicerids, cholesterol and creatinine levels. Triceps skindfold and arm/muscle circumference were measured the day before surgery. The body mass index was calculated based on the information contained in the anaesthetic chart. We also collected information about co-morbidities such as Diabetes, High blood pressure, ASA grading, age and gender. Information about early infections, both superficial and deep, was collected. A descriptive statistical analysis and logistic regression models approach for independent risk factors were performed.

Results: The mean age was 71.5 years. There were 162 female and 51 male. Eleven patients (5.16%) had early wound infection: 5 deep EPJI and 6 superficial. Neither co-morbidities nor preoperatively laboratory test except CRP (OR 1.44, p=0.03) were associated with a high early infection risk. However, there was an inversely proportional relationship between EPJI and anthropometric measurements: triceps skindfold (OR 0.9 p=0.011) and fat area (FA) (OR 0.94, p=0.01).

Conclusion: A low triceps skindfold and FA were associated with an increment of risk of EPJI after a knee replacement. Although the relationship between some laboratory test as pre-albumin and lymphocyte account and wound healing and postoperatively complications is well known, we didn’t find it with EPJI in our group except for CRP levels.

Introduction: The histology of prosthetic tissue is a gold standard for the diagnosis of prosthetic joint infection. However, the specificity and sensitivity of histology has never been 100% and this could be due to several causes. A possible cause for inconsistencies in histological results could be the type of specimen submitted to laboratory. The majority of authors obtain specimens from pseudocapsule, interface membrane and any tissue area suspicious of infection.

Aim: The objective of our study was to elucidate which is the most accurate specimen for histological diagnosis of prosthetic joint infection.

Methods: Prospective study including all revision arthroplasties performed in Hospital Clinic of Barcelona (Spain) from January 2007 to June of 2009. Specimens from pseudocapsule and from interface membrane were obtained from each patient. Definitive diagnosis of infection was considered when ≥2 cultures were positive for the same microorganism or the presence of pus around the prosthesis. Patients were classified in two groups:

patients submitted to hip revision arthroplasty due to an aseptic loosening in whom cultures (at least 5) obtained during surgery were negative and

Results: A total of 69 revisions were included in the study; 57 were classified in the group A and 12 were classified in the group B. The percentage of positive interface membrane histology in patients with prosthetic joint infection (group B) was significantly higher than the percentage of positive pseudocapsule histology (83.3% vs 41.6%, p=0.04, Fisher exact test).

Conclusion: The results suggest that the best specimen of periprosthetic soft tissue for histological study to diagnose the chronic periprosthetic infection in a revision total hip arthroplasty is the periprosthetic interface membrane.

Introduction: The most important cause of prosthetic joint infection (PJI) is the contamination of the wound during the surgery. Nowadays, it doesn’t exist any image or laboratory test for early detection of prosthesis with a higher risk of developing a PJI.

Aim: The primary aim was to evaluate the usefulness of different intraoperative samples during the surgery of implantation of a primary hip arthroplasty (PHA) as a predicting factor of PJI.

Methods: A prospective cohort study was performed. All patients (n= 278) who underwent a PHA from January ’06 to November ’08 were included. Three samples: a piece of articular capsule (TS), a swab (S) and synovial fluid (SF) inoculated into blood flask were taken in each patient during the first 45 minutes of surgery. Other possible risk factors of PJI like age, sex, ASA, comorbidity and surgical time were registered.

Results: A total of 278 patients were included. 30 cultures (8 SF, 13 TS and 9 S) were positive in 29 patients. The most frequent microorganism isolated was Coagulase-negative staphylococci (CNS) (66.6%). The rate of PJI (early and late) in the subgroup of patients with positive intraoperative cultures for CNS was 25% while in the subgroup with all negative cultures was 5.2% (RR=4.8; p=0.007). Other factors significantly associated with a higher rate of PJI in the univariate analysis were: ASA III (RR=9.12; p=0.02), cardiopathy (RR= 2.82; p=0.04), obstructive pulmonary chronic disease (RR=5; p=0.02) and rheumatoid arthritis (RR=4.16; p=0.04). Multivariate analysis found ASA III (Odds ratio 10.9; CI 95% 1.27–94.6; p=0.02) and a positive intraoperative culture for CNS (Odds ratio 5.92; CI 95%=1.8–19.85; p=0.03) as independent risk factors for PJI.

Conclusion: Positive intraoperative culture for CNS during PHA was independently associated with the development of PJI.

Exchange of infected implant using antibiotic-impregnated cement is the treatment of choice in prosthetic joint infection (PJI). We presented our experience using one or two-stage exchange with uncemented implants.

From January 2000 to June 2006 patients with a PJI that were treated with one or two-stage exchange with uncemented implants, were prospectively followed up. The treatment protocol consisted of radical excision of devitalized tissue and of maintaining a high serum antibiotic concentration during surgery followed by systemic antibiotic administration according to the microbiology results. Only patients with ≥6 months of follow-up were included. Good evolution was considered when symptoms and signs of infection disappeared and the C-Reactive Protein was normal.

Forty-two patients were included in the study, of whom 25 were male. The mean age was 70 years. The most common symptom was pain (100%) and radiological signs of prosthesis loosening were present in 36 cases (85.7%). Histology was positive in 32 patients (76.2%). Coagulase-negative staphylococci was the most common microorganism (23 cases) followed by S. aureus (5 cases). One-stage exchange was performed in 18 patients, and the long stem component was always uncemented. In one case an acute infection after the arthroplasty obligated to perform an open debridément without implant removal. After a mean follow-up of 31 months (range: 6–84) all patients had a good evolution. In 24 cases a 2-stage exchange with a joint spacer with gentamycin (Spacer-G) was performed. In all cases the definitive arthroplasty was performed using an uncemented long stem. Good evolution was documented in all but one case with persistent infection due to S. aureus after a mean follow-up of 19 months (range: 12–48).

Our results suggest that uncemented arthroplasty following a protocol based on radical debridément and systemic antibiotic therapy during and after surgery is a useful approach in PJI.

Purpose: To review the results of periprosthetic femoral fractures treated using cortical strut allograft and plate internal fixation.

Material & Methods: Between November 1996 and July 2006, 17 patients with periprosthetic fractures of the femur after hip arthroplasty were treated using deep-frozen cortical strut allografts as an adjunct support after internal fixation. The average age was 79 years (range 56 to 96 years) with 13 woman and 4 men. According to the Vancouver classification system, there were 6 type B1, 5 type B2, 1 type B3 and 5 type C fractures. All fractures were closed except for one type I of Gustilo. Twelve patients had internal fixation of the fracture using a Dall-Miles cable and plate system, 5 using a AO/ASIF 4.5 dynamic compression plate, and 2 had an associated revision arthroplasty of the stem. Cortical strut allograft was used from the femur in 6 cases and from the tibia in 11 cases. Mean follow-up was of 97.5 weeks.

Results: One patient presented a rupture of a screw and varus displacement of the fracture, but healed without symptomatic complaints. A superficial infection occurred in the patient with open fracture. All the patients, except for two, required allogenic blood transfusion. Mean inhospital stay was of 18.6 days and walk with weigh was allowed at a mean of 50.9 days. Two patients died few weeks after the treatment due to complications of their previous pathological disorders. Aseptic loosening of a hip arthroplasty occurred at two years follow-up requiring revision surgery. Three patients referred mild pain at the last follow-up visit.

Conclusions: Cortical strut allograft associated with internal fixation has provided satisfactory results in the present serie. We consider this procedure safe and effective, specially for type B1 and C periprosthetic femoral fractures.