This study was performed to investigate the concentration of silver ions release up to a time of 9 weeks as well as the antimicrobial activity of silver sulfate and Nano-silver mixed bone cement on Candida albicans, in expectation of a new way of therapy in manner of a time limited application – a silverions releasing bone cement spacer.

Two different kinds of silver products were used and mixed with polymethylmetacrylate (PMMA, De Puy) bone cement:

Nano-silver with a particle size of 5–50 nm and active surface of 4 m2/ g. (Nanonet Styria, Austria)

Concentrations of 0.1%, 0.5%, 1% and 5% of the Nano-silver and the silver-salt by weight were mixed with the dry powder portion of the cement. To test the silver-ions release from the silver-containing bone cement two models of elution, a static model and a dynamic model were created. To test the antifungal effectiveness of the various concentrations of Ag-PMMA the bone cement samples were tested by agar diffusion assay.

With respect to minimal inhibition concentration (MIC) the sample containing 0.5 % silver sulfate showed required concentration at the dynamic elution model but none of the nano-silver samples did. In static elution model we measured the maximum concentration of 466.5 µg/l at the 0.5 % silver sulfate sample which is much below the toxic concentration. Agar diffusion assay showed no zone of inhibition from Nano-silver samples. In contrast, silver sulfate containing samples showed a zone of inhibition exactly growing, depending on the samples silver sulfate concentration.

According to results, silver sulfate addition to PMMA might be another approach in treatment of candida associated periprosthetic joint infection.

Introduction: Infections associated with prosthetic joints cause significant morbidity and account for substantial costs for health care systems. The management of prosthetic joint infections is less standardized, because of the variable clinical presentations and the lack of data from randomized, controlled trials.

We evaluated the results of surgical one stage versus two stage exchange of patients diagnosed positive for prosthetic infection following total hip replacement in correlation with a classification described by Mc Pherson.

Material and Methods: 94 patients were diagnosed positive for prosthetic joint infection following total hip replacement in the years 1995 to 2004: gender distribution was 45 male and 49 female patients. 37 patients were treated with a one stage exchange, 57 patients underwent a two step procedure. Patients were further divided into two groups following the mentioned classification described by Mc Pherson as infection type I+II and III. Further characterisation was performed following systemic host grade (A versus B+C) and local extremity grade 1 versus 2+3.

Results: Eradication of prosthetic infection was achieved in 94, 5% (n=52) within the group of two stage exchange and 56, 8% (n=21) of patients treated with a one stage procedure. Outcome of patients following a one stage or a two step exchange was overall significantly different with p< .001. Further deviations between the described two procedures were noted in the subgroups following the classification described by Mc Pherson. A benefit of patients who underwent a two step procedure was seen according the severity of the classification following Mc Pherson.

Conclusion: Eradication rate of prosthetic joint infections differs statistically significant overall and in the subgroups following Mc Pherson in dependence of the surgical procedure. For this reason the individual surgical procedure should be geared to an algorithm, following the classification described by Mc Pherson.

Introduction: Prosthetic joint infections occur in 1–2 % following total knee replacement. Different options of treatment are described in literature with a lack of data from randomized, controlled trials.

We classified septic revision surgeries following total knee according to a classification published by Mc Pherson. Eradication rate of one stage versus two stage exchange was compared.

Materials and Methods: We included 74 patients who underwent septic revision surgeries following total knee replacement in the years 1998 to 2005. Gender distribution was 42 female and 32 male patients. The mean age at revision surgery was 71 years, at primary implantation mean 68,8 years.

Results: The eradication rate overall was 77 %, in one stage exchange 41.7% and in two stage procedures 86%. Multiple stage revision showed an eradication rate of 75%, necrectomy/debridement 50%, arthrodesis and amputation 100%.

Regarding Mc Pherson’s systemic grades classification the eradication rate for two stage exchanges was 85,7% in group A+B and 60%% in group C. One stage procedures achieved 0% eradication rate in group B and 60% in group C. Regarding Mc Pherson’s local extremity grade classification eradication rates within two stage revisions were 84% in group 2 and 75% in group 3. One stage revision achieved 40% and 0%.

Conclusion: Although two stage revision surgeries achieved better results regarding eradication rates then one stage revision surgery, results were statistically not significant. Reason could be a too small number of included patients for a significant statistical impact. The individual surgical procedure should orientate on the classification published by Mc Pherson.