Characterization of hip and knee arthroplasties and factors associated with infection

ObjectiveTo characterize arthroplasty procedures, calculate the surgical infection rate and identify related risk factors.MethodsThis was a retrospective cohort study. Data on operations performed between 2010 and 2012 were gathered from documental sources and were analyzed with the aid of statistical software, using Fisher's exact test, Student's t test and the nonparametric Mann–Whitney and Wilcoxon tests.Results421 total arthroplasty procedures performed on 346 patients were analyzed, of which 208 were on the knee and 213 on the hip. It was found that 18 patients (4.3%) were infected. Among these, 15 (83.33%) were reoperated and 2 (15.74%) died. The prevalence of infection in primary total hip arthroplasty procedures was 3%; in primary total knee arthroplasty, 6.14%; and in revision of total knee arthroplasty, 3.45%. Staphylococcus aureus was prevalent. The length of the surgical procedure showed a tendency toward being a risk factor (p = 0.067).ConclusionThe prevalence of infection in cases of primary total knee arthroplasty was greater than in other cases. No statistically significant risk factors for infection were identified.

ResumoObjetivoCaracterizar as artroplastias, calcular a taxa de infecção cirúrgica e identificar fatores de risco relacionados.MétodosEstudo de coorte retrospectivo. Os dados das cirurgias feitas entre 2010 e 2012 foram coletados em fontes documentais e analisados com auxílio de programa estatístico e testes exato de Fisher, t de Student e não paramétrico de Mann–Whitney e Wilcoxon.ResultadosForam analisadas 421 artroplastias totais em 346 pacientes, 208 de joelho e 213 de quadril; 18 (4,3%) pacientes infectaram; entre esses, 15(83,33%) foram reoperados e dois (15,74%) evoluíram para óbito. A prevalência de infecção em artroplastia total de quadril primária foi de 3%, em artroplastia total de joelho primária de 6,14% e em revisão de artroplastia total de joelho de 3,45%; Staphylococcus aureus foi prevalente. O tempo de duração da cirurgia indicou uma tendência como fator de risco (p = 0,067).ConclusãoA prevalência de infecção em artroplastia total de joelho primária foi superior às demais e não foram identificados fatores de risco para infecção com significância estatística.