Treatment of knee prosthesis infections: evaluation of 15 patients over a 5-year period

Our objective was to evaluate different treatment alternatives for total knee arthroplasty (TKA) infection and to compare outcomes depending on adherence to a current treatment algorithm. All patients treated for a first episode of TKA infection between January 2000 and July 2005 were included. Patient records were reviewed and data were extracted retrospectively. Fifteen patients were followed up for a median of 25 months. The cure rate in patients with two-stage exchange of knee prosthesis was higher than in patients who had débridement without implant removal (100 vs 37%, p = 0.03). Cure rates were not different between these two surgical approaches in ten patients who were treated according to a current treatment algorithm. Success rates for treatment of TKA infections varied considerably with the treatment strategy chosen. Our results support the use of existing algorithms to select patients who are eligible for débridement with retention of the prosthesis or need two-stage exchange of knee implants

Diagnosis and Management of Infected Total Knee Arthroplasty§

Infection following total knee arthroplasty can be difficult to diagnose and treat. Diagnosis is multifactorial and relies on the clinical picture, radiographs, bone scans, serologic tests, synovial fluid examination, intra-operative culture and histology. Newer techniques including ultrasonication and molecular diagnostic studies are playing an expanded role. Two-stage exchange arthroplasty with antibiotic cement and 4-6 weeks of intravenous antibiotic treatment remains the most successful intervention for infection eradication. There is no consensus on the optimum type of interval antibiotic cement spacer. There is a limited role for irrigation and debridement, direct one-stage exchange, chronic antibiotic suppression and salvage procedures like arthrodesis and amputation. We examine the literature on each of the diagnostic modalities and treatment options in brief and explain their current significance

Tratamento das infecções pós artroplastia total de joelho: resultados com 2 anos de seguimento Treatment of infections following total knee arthroplasty: 2-year follow-up outcomes

INTRODUÇÃO: A (ATJ) Artroplastia Total do Joelho é cirurgia de grande porte e sujeita a complicações pós operatórias, sendo a infecção uma das piores e mais temidas. No Instituto de Ortopedia e Traumatologia da Faculdade de Medicina da Universidade de São Paulo, a incidência de infecção nas ATJ tem se mantido ao redor de 3% nos últimos 3 anos. O objetivo desse estudo é analisar e padronizar o protocolo de tratamento das infecções pós artroplastia total de joelho. MATERIAIS AND MÉTODOS: Dentre os anos de 2003 e 2004, vinte e nove pacientes com o diagnóstico de infecção pós artroplastia total de joelho primária foram submetidos a o protocolo de tratamento, sendo o período médio de seguimento 20 meses. Dentre os casos nove eram de infecção superficial, três de infecção profunda aguda, e dezoito de infecção profunda crônica. A classificação é baseada em critérios clínicos locais e no tempo de apresentação dos sintomas. RESULTADOS: Foram tratados oito pacientes com quadro de infecção superficial e três pacientes com infecção profunda aguda, com índice de cura de 100%, sem nenhuma recidiva. Foram tratados dezoito casos de infecção profunda crônica, com cura sem recidiva no período de seguimento em 14 pacientes. CONCLUSÃO: Consideramos nossos resultados e nosso protocolo de tratamento adequados e compatíveis com a literatura.<br>OBJECTIVE: The objective of this study is to analyze and standardize the treatment protocol of infections following total knee arthroplasty proposed by the Knee Group and the Infectology Group of IOT-HC-FMUSP. MATERIALS AND METHODS: Between 2003 and 2004, twenty-nine patients (19 women and 10 men, mean age: 67 years) diagnosed with infection after total primary knee arthroplasty were hospitalized at IOT-HC FMUSP (Institute of Orthopedics and Traumatology of Hospital das Clínicas, Medical College, University of Sao Paulo, SP, Brazil) and subjected to a treatment protocol. The mean follow-up time was 20 months. Nine cases had superficial infections, three had acute deep infections and eighteen had chronic deep infections. The classification is based on local clinical criteria and on the time of symptoms onset. RESULTS: Eight patients with superficial infection and three patients with acute deep infection were treated, showing good outcomes and no recurrence cases. Eighteen patients with chronic deep infection were treated and cured, 14 of whom with no recurrence during the follow-up period. CONCLUSION: We regard our outcomes and treatment protocol as appropriate and consistent with literature

The microbiology of the infected knee arthroplasty

We describe the results of a retrospective analysis of patients with microbiologically proven infection, who underwent revision TKA between 1994 and 2008. Of the 121 patients included in the study, 61 (50%) were male and 60 (50%) were female. The mean age was 71 (range 42–88) years. The most common organisms identified were Coagulase negative Staphylococcus (CNS) (49%) and Staphylococcus aureus (SA) (13%). The prevalence of CNS appears to be increasing, while that of SA and other organisms is decreasing. Vancomycin and teicoplanin were the most effective antibiotics with overall sensitivity rates of 100% and 96%, respectively. The results of our theoretical model suggest that gentamicin combined with vancomycin is the most effective empirical regimen. Staphylococcal species are the most common organisms encountered in deep infection of the knee. Gentamicin combined with vancomycin offers the most comprehensive protection and potentially allows for infected knee arthoplasties to be treated with a one-stage procedure