Infected total knee arthroplasty treatment outcome analysis

Infected total knee arthroplasty (TKA) is a topic of great importance, because its diagnosing and treatment requires a lot of resources, and often has an unsatisfactory outcome. The aim of this study was to analyze the outcome of the treatment of infection developed following TKA.

This retrospective study of infected TKAs was performed in the period from 1998 to 2008 in the Orthopedics & Traumatology Clinic of the Military Medical Academy (MMA) in Belgrade. A total of 654 primary and revised TKAs were performed in the said period. We registered and surgically treated 28 infected TKAs (primary TKAs: MMA--22, other institutions--6). The incidence of TKA infection in the MMA was 3.36%. The most common pathogens were: Staphylococcus aureus--14 (50%) cases, and Staph. epidermidis--3 (10.7%) cases. Other isolated pathogens were: Enterococcus faecalis, Klebsiella pneum., Klebsiella spp., Streptoccocus viridans, Seratia spp, Micrococcus luteus and Peptostreptococcus spp. In one case we had mixed anaerobic flora, and in 3 cases cultures were negative. We analyzed diagnostic challenges, risk factors (such as age and previous viscosupplementation) and treatment outcomes in our series of infected TKAs.

In our series 2 infections healed after iv antibiotics and debridement, 1 patient responded to open debridement with component retention, 4 patients responded fully to one-stage reimplantation, 10 cases responded fully to two-stage reimplantation, 11 patients ended with arthrodesis and we had 1 patient withabove knee amputation.

Two-stage reimplantation remains gold standard for treatment of infected TKA, and we recommend it as treatment of choice for eradication of infection. The antibiotic loaded spacer prothesis concept in most cases allows infection eradication, good function and high patient satisfaction.