Infección periprotésica de rodilla ¿influye la estrategia quirúrgica en el resultado funcional? / Total knee arthroplasty infection, what is the best strategy for better functional outcomes?

Resumen: Introducción: La estrategia quirúrgica al enfrentarnos a las infecciones periprotésicas de rodilla sigue siendo controvertida. Los objetivos del tratamiento son la erradicación de la infección, la mejoría del dolor y de la función articular. El manejo quirúrgico incluye el desbridamiento y retención del implante, el recambio protésico en un tiempo o el recambio en dos tiempos. Esta última estrategia quirúrgica se considera el «gold standard¼, alcanzando unas tasas de curación hasta de 80%-100%, aunque poco se ha publicado acerca de los resultados funcionales. Material y métodos: Estudio retrospectivo de 65 pacientes, con infección periprotésica de rodilla. En 20 pacientes se realizó un recambio en un tiempo y en 45 pacientes fueron recambios en dos tiempos. Evaluación pre- y postoperatoriamente con la escala modificada HSS. Todos los pacientes fueron tratados con antibioterapia intravenosa, evaluamos la respuesta analítica y clínica para confirmar la erradicación o no de la infección. Resultados: La infección se resolvió en 39 de 65 pacientes, 12 en el grupo de recambio en un tiempo y 27 para el grupo de dos tiempos. Sin diferencia significativa entre los grupos en relación con curación ni resultado funcional. Sin embargo, hay una diferencia estadísticamente significativa entre aquellos pacientes que recibieron tratamiento antibiótico vía oral antes del diagnóstico y aquéllos que no lo recibieron. Conclusión: La tasa de curación es similar en los tratados con recambio en un tiempo y recambio en dos tiempos. No pudimos demostrar superioridad en los resultados funcionales entre los dos grupos.

Abstract: Introduction: Surgical strategy in dealing with periprosthetic knee infections remains controversial. The goals of treatment are to eradicate infection, improve pain and joint function. Surgical management includes implant debridement and retention, prosthetic replacement in one-time, or two-stage replacement. This latest surgical strategy is considered the «gold standard¼, reaching healing rates up to 80%-100%, although little has been published about functional results. Material and methods: Retrospective study of 65 patients with periprosthetic knee infection. In 20 patients a replacement was made in a time and in 45 patients were in two stages. Pre- and post-operative evaluation with the modified HSS scale. All patients were treated with intravenous antibiotherapy, we evaluated the analytical and clinical response to confirm the eradication or not of the infection. Results: The infection was resolved in 39 out of 65 patients, 12 in the replacement group in a time and 27 for the two-stages group. No significant difference between the groups in relation to healing or functional result. However, there is a statistically significant difference between those patients who received oral antibiotic treatment prior to diagnosis and those who did not. Conclusions: The healing rate is similarly treated with replacement in a time and replacement in two times. We were unable to demonstrate superiority in the functional results between the two groups.

Predictors for outcome of exchange arthroplasty for periprosthetic joint infections after primary total knee arthroplasty / 中华传染病杂志

Objective To evaluate the overall failure rate of one or two-stage exchange arthroplasty for infections in total knee arthroplasty (TKA) and the predictors affecting the outcome of exchange.Methods Thirty-nine cases received one or two-stage exchange arthroplasty for periprosthetic joint infections after primary TKA in Shanghai Sixth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine and Southeast Hospital affiliated to Xiamen University from January 2012 to November 2014 were reviewed.Periprosthetic tissue and articular fluid of all patients were analyzed by bacterial culture.All patients were followed up for more than one year.C-reactive protein (CRP),erythrocyte sedimentation rate (ESR),procalcitonin (PCT) and blood routine were tested every four weeks,and the evaluation on pain,total periprosthetic function,range of motion and deformation of arthroplasty were conducted.Differences between groups were analyzed using chi-square test or Student's t test when appropriate.A stepwise selection approach in logistic regression analysis was used to screen key predictors for outcome of one or two-stage exchange for infections in TKA.Results There were 39 patients who had undergone one or two-stage exchange for infections in TKA,including 20 males (51.3％) and 19 females (48.7％) with an average age of (62.4±11.7) years.Among the 39 patients,18 gram-positive strains were isolated from specimens,and 6 gram negative strains,2 Mycobacterium tuberculosis and 1 candida albicans.Ten of 39 reimplantations developed reinfection.Between the success and failure groups,there were significant differences in the time from primary TKA to revision (P =0.023),operative time (P =0.029),multidrug resistant organisms (P =0.045),the preoperative and post-operative ESR (P=0.002 and P＜0.001,respectively) and post-operative CRP (P=0.018).Multivariable logistic regression analysis demonstrated that time from primary TKA to revision (OR =0.96,95％CI:0.92-1.00,P=0.025),preoperative ESR (OR=0.97,95％CI:0.95-1.00,P=0.045) and post-operative ESR (OR =0.94,95％ CI:0.91-0.98,P =0.002) were independent indicators associated with the outcome of one or two-stage revision.Conclusions The failure rate after revision for infected TKA is relatively high.The time from primary TKA to revision,preoperative and post-operative ESR could predict the outcome of one or two-stage revision effectively.