title: Implementation of an Algorithm for Prosthetic Joint Infection: Deviations and Problems.
abstract: BACKGROUND
  The outcome of revision surgery in arthroplasty is based on a precise diagnosis. In addition, the treatment varies based on whether the prosthetic failure is caused by aseptic or septic loosening. Algorithms can help to identify periprosthetic joint infections (PJI) and standardize diagnostic steps, however, algorithms tend to oversimplify the treatment of complex cases. We conducted a process analysis during the implementation of a PJI algorithm to determine problems and deviations associated with the implementation of this algorithm.
  
  
  METHODS
  Fifty patients who were treated after implementing a standardized algorithm were monitored retrospectively. Their treatment plans and diagnostic cascades were analyzed for deviations from the implemented algorithm. Each diagnostic procedure was recorded, compared with the algorithm, and evaluated statistically.
  
  
  RESULTS
  We detected 52 deviations while treating 50 patients. In 25 cases, no discrepancy was observed. Synovial fluid aspiration was not performed in 31.8% of patients (95% confidence interval [CI], 18.1%-45.6%), while white blood cell counts (WBCs) and neutrophil differentiation were assessed in 54.5% of patients (95% CI, 39.8%-69.3%). We also observed that the prolonged incubation of cultures was not requested in 13.6% of patients (95% CI, 3.5%-23.8%). In seven of 13 cases (63.6%; 95% CI, 35.2%-92.1%), arthroscopic biopsy was performed; 6 arthroscopies were performed in discordance with the algorithm (12%; 95% CI, 3%-21%).
  
  
  CONCLUSIONS
  Self-critical analysis of diagnostic processes and monitoring of deviations using algorithms are important and could increase the quality of treatment by revealing recurring faults.
authors.affiliation: 1 Department of Orthopedic Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany .
authors.forename: Heinrich M L
authors.initials: HM
authors.lastname: Mühlhofer
authors.affiliation: 2 Department of Trauma Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany .
authors.forename: Karl-Georg
authors.initials: KG
authors.lastname: Kanz
authors.affiliation: 1 Department of Orthopedic Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany .
authors.forename: Florian
authors.initials: F
authors.lastname: Pohlig
authors.affiliation: 1 Department of Orthopedic Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany .
authors.forename: Ulrich
authors.initials: U
authors.lastname: Lenze
authors.affiliation: 1 Department of Orthopedic Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany .
authors.forename: Florian
authors.initials: F
authors.lastname: Lenze
authors.affiliation: 1 Department of Orthopedic Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany .
authors.forename: Andreas
authors.initials: A
authors.lastname: Toepfer
authors.affiliation: 1 Department of Orthopedic Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany .
authors.forename: Ruediger
authors.initials: R
authors.lastname: von Eisenhart-Rothe
authors.affiliation: 1 Department of Orthopedic Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany .
authors.forename: Johannes
authors.initials: J
authors.lastname: Schauwecker
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001182:Arthroscopy; D001706:Biopsy; D006801:Humans; D008875:Middle Aged; D016459:Prosthesis-Related Infections / Q000175:diagnosis / Q000453:epidemiology / Q000601:surgery; D012086:Reoperation; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: algorithm; prosthetic joint infection; revision arthroplasty