The current antibiotic treatment of periprosthetic joint infection (PJI) is optimized by measuring concentrations in plasma. However, it remains unclear whether effective concentrations of the antibiotics are reached at the site of PJI. Nonetheless, adequate target site concentrations are important to achieve effective eradication of the micro-organism. In order to determine the efficacy of cefuroxime and flucloxacillin in synovial fluid, synovial tissue and bone tissue in relation to the minimal inhibitory concentration (MIC) of the pathogen causing the PJI, we perform a pharmacokinetic/pharmacodynamic (PK/PD) study. Therefore, we aimed to develop validated analytical methods for analysis of cefuroxime and flucloxacillin in synovial fluid, synovial tissue and bone tissue. Blank samples of synovial fluid, synovial tissue and bone tissue were obtained by orthopedic surgeons during surgery. For validation the samples of each matrix were spiked with both cefuroxime and flucloxacillin. Synovial tissue and bone tissue was pulverized with a mikro-dismembrator. Samples were kept frozen at −20°C until analysis. After a sample preparation quantification of cefuroxime and flucloxacillin in each matrix was performed on the ultra-performance convergence chromatography-tandem mass spectrometry (UPC2-MS/MS). Stable-isotope-labeled meropenem-d6 served as internal standard. The linearity, limits of quantification, accuracy and precision and carry-over were determined for all methods separately. The methods were validated according to the European Medicine Agency (EMA) and Food and Drug Administration (FDA) guidelines on bioanalytical method validation.Aim
Method
Aim was to compare revision rates when using single versus dual antibiotic loaded cement (ABLC) in hip fracture arthroplasty and aseptic revision hip or knee arthroplasty using data from the Dutch national joint registry (LROI). All primary cemented (hemi-)arthroplasties for acute hip fractures and cemented aseptic hip or knee revision arthroplasties, were incorporated in 3 datasets. All registered implants between 2007 and 2018 were included (minimum 2 years follow-up). Primary end-point was subsequent revision rates for infection and for any reason in the single and dual ABLC groups. Cumulative crude incidence of revision was calculated using competing risk analysis.Aim
Methods
The duration and extent of postoperative wound leakage after joint arthroplasty in patients with or without a complicated course, like a prosthetic joint infection (PJI), is currently unknown. Adequate differentiation between normal postoperative wound leakage and wound leakage due to a postoperative PJI is important and prevents unnecessary surgical procedures. We investigated the association between postoperative wound leakage and development of PJI in patients who used a previously developed mobile wound care app. A multicenter, prospective cohort study with patients aged 18 years or older after primary implantation or revision of a total joint arthroplasty. During 30 post-operative days after arthroplasty, patients recorded their wound status in the woundcare app. An algorithm calculated a daily score from imputed data. If the daily score exceeded a predefined threshold, the patients received an alert that advised them to contact their physician.Background
Methods
Debridement Antibiotics and Implant Retention(DAIR) is a procedure to treat a periprosthetic joint infection(PJI) after Total Hip Arthroplasty(THA) or Total Knee Arthroplasty(TKA). The timing between the primary procedure and the DAIR is likely a determinant for its successful outcome. There are few retrospective studies correlating timing of a DAIR with success (1,2). However, the optimal timing of a DAIR and the chance of success still remains unclear. We aimed to assess the risk of re-revision within one year after a DAIR procedure and to evaluate the timing of the DAIR in primary THA and TKA. An estimation of the chance of a successful DAIR will help clinicians and patients in their decision-making process in case of an acute postoperative PJI. We used data from the Dutch Arthroplasty Register(LROI) and selected all primary THA and TKA in the period 2007–2016 who underwent a DAIR within 12 weeks after primary procedure. A DAIR was defined as a revision for infection in which only modular parts were exchanged. A DAIR was successful if not followed by a re-revision within 1 year after DAIR. The analyses were separated for THA and TKA procedures.Aim
Method
Radiographs of the scaphoid after injury are difficult to interpret, and bone scintigraphy is widely used to increase the accuracy of diagnosis, though many fractures suspected on scintigraphy cannot be confirmed radiologically. We have reviewed the clinical consequences, after one year, of managing suspected scaphoid fractures according to the bone-scan results. We studied 160 patients, 35 of whom had initially positive radiographs and were treated in a cast for 12 weeks. The other 125 had bone scintigraphy and were managed according to the result. After a minimum of one year 119 patients were reviewed. Scintigraphically suspected scaphoid fracture could not be confirmed radiologically in 25%. There were no cases of nonunion. The long period of immobilisation in patients with positive radiographs or positive bone scans did not influence the frequency or severity of late symptoms compared with those with a normal bone scan.
