Two stage exchange has been the gold standard in North America for the treatment of infected knee replacements. The choice of static vs. articulated spacers has been debated for a number of years. At our institution our choice of spacer for 2 stage exchanges is an articulated spacer. This allows motion between stages which facilitates recovery, and makes the second stage technically easier. In a study from our institution we followed 115 infected TKAs treated with the PROSTALAC articulated spacer for 5–9 years. Success for eradication of infection was 88%. With a repeat 2 stage, overall infection control was 98%. In addition, we compared functional outcomes to a group of aseptic knee revisions and found no difference in functional outcomes with standard quality of life outcome scores. While the articulated spacer was our treatment of choice in 2 stage exchange around 2012, the company that manufactured the PROSTALAC knee components ceased to manufacture them. At that time, based on the work of 2 previous studies (Hofmann, Lee), we continued to use articulated spacers. However, this was now the so-called Hofmann technique with a new standard femoral component with an all polyethylene tibia. The only difference from a standard knee revision was no stems and the utilization of high dose antibiotics. We also followed the principles from Europe of one stage exchange, such as wide debridement and soaking in dilute betadine for 15 minutes. More recently as of Sept 2015 we have used an all polyethylene tibia with a keel. The hope being that this will give a more stable tibia than previous and perhaps make a second stage unnecessary. Our first case was September 2015. The intention was not to do a second stage if the infection was eradicated and the patient had good pain relief and function. To date we have implanted 28 of these and in 80% of cases we have not had to do a second stage revision. Further study will reveal where this inadvertent one stage fits in our practi

Two stage exchange has been the gold standard in North America for the treatment of infected knee replacements. The choice of static versus articulated spacers has been debated for a number of years. At our institution our choice of spacer for two-stage exchanges is an articulated spacer. This allows motion between stages which facilitates recovery, and makes the second stage technically easier. In a study from our institution we followed 115 infected TKAs treated with the PROSTALAC articulated spacer for 5–9 years. Success for eradication of infection was 88%. With a repeat two stage overall infection control was 98%. In addition we compared functional outcomes to a group of aseptic knee revisions and found no difference in functional outcomes with standard quality of life outcome scores. While the articulated spacer was our treatment of choice in two-stage exchange around 2012 the company that manufactured the PROSTALAC knee components ceased to manufacture them. At that time based on the work of 2 previous studies (Hofmann, Lee), our institution continued to use articulated spacers. However, this was now the so-called Hofmann technique with a new standard femoral component with an all-polyethylene tibia. The only difference from a standard knee revision was no stems and the utilisation of high dose antibiotics. We also followed the principles from Europe of one-stage exchange, such as wide debridement and soaking in dilute betadine for 15 minutes. More recently, as of Sept 2015, we have used an all-polyethylene tibia with a keel. The hope being that this will give a more stable tibia than previous and perhaps make a second stage unnecessary. Our first case was September 2015. The intention was not to do a second stage if the infection was eradicated and the patient had good pain relief and function. To date we have implanted 12 of these and in all cases we have not had to do a second stage revision. Further study will reveal where this inadvertent one stage fits in our practice

Two-stage exchange has been the gold standard in North America for the treatment of infected knee replacements. The choice of static versus articulated spacers has been debated for a number of years. At our institution our choice of spacer for 2-stage exchanges is an articulated spacer. This allows motion between stages which facilitates recovery, and makes the second stage technically easier. In a study from our institution we followed 115 infected TKAs treated with the PROSTALAC articulated spacer for 5–9 years. Success for eradication of infection was 88%. With a repeat two-stage, overall infection control was 98%. In addition, we compared functional outcomes to a group of aseptic knee revisions and found no difference in functional outcomes with standard quality of life outcome scores. While the articulated spacers were our treatment of choice in 2-stage exchange, around 2012 the company that manufactured the PROSTALAC knee components ceased to manufacture them, based on the work of 2 previous studies (Hofmann, Lee). At our institution, we continued to use articulated spacers. However, this was now the so-called Hofmann technique with a new standard femoral component with an all-polyethylene tibia. The only difference from a standard knee revision was no stems and the utilization of high dose antibiotics. Around the same time as we instituted the change in articulated spacers, results out of Europe were showing promising results with one-stage exchange. In September 2015, our technique was modified to now include an all-polyethylene tibia with a keel. To date we have no results but it is our hope that a high percent of these will achieve stable fixation and will then have a one-stage exchange

Two stage exchange has been the gold standard in north America for the treatment of infected knee replacements. The choice of static versus articulated spacers has been debated for a number of years. At our institution our choice of spacer for 2 stage exchanges is an articulated spacer. This allows motion between stages which facilitates recovery, and makes the second stage technically easier. In a study from our institution we followed 115 infected TKAs treated with the PROSTALAC articulated spacer for 5–9 years. Success for eradication of infection was 88%. With a repeat two stage overall infection control was 98%. In addition we compared functional outcomes to a group of aseptic knee revisions and found no difference in functional outcomes with standard quality of life outcome scores. While the articulated spacers was our treatment of choice in 2 stage exchange around 2012 the company that manufactured the PROSTALAC knee components ceased to manufacture them. At that time based on the work of 2 previous studies (Hofmann, Lee), at our institution we continued to use articulated spacers. However, this was now the so called Hofmann technique with a new standard femoral component with an all polyethylene tibia. The only difference from a standard knee revision was no stems and the utilization of high dose antibiotics. We also followed the principles from Europe of one stage exchange, such as wide debridement and soaking in dilute betadine for 15 minutes. More recently as of Sept 2015 we have used an all-polyethylene tibia with a keel. The hope being that this will give a more stable tibia than previous and perhaps make a second stage unnecessary. Our first case was September 2015. The intention was not to do a second stage if the infection was eradicated and the patient had good pain relief and function. To date we have implanted 12 of these and in all cases we have not had to do a second stage revision. Further study will reveal where this inadvertent one stage fits in our practice

The purpose of the following study was to present the general strategy for preserving the lower extremity by knee arthrodesis and to analyze the outcome of knee arthrodeses performed by a special modular system. Between 2009 and 2014 35 knee arthrodeses were performed. 23 patients were male, 12 female. The average age was 66 years (42 to 83 years). The patients underwent an average of 6 operations because of infected knee arthroplasties previous to the knee arthrodesis. The main pathogen was S. epidermidis followed by MRSA. The arthrodeses system included a non cemented femoral and tibial stem (press fit application plus two static locking screws). These were connected by a special stem to stem clamp. Immediate postoperative full weight-bearing was possible in 32 of 35 patients. We saw 4 recurrent infections (all connected to the patients, who did not show a full weight bearing after knee arthrodesis). In two cases re-revision surgery was successful and lead to a sufficient re-arthrodesis. In two cases above-knee-amputation was necessary. Peri-implant fractures were detected in 3 cases. All of them could be cured by changing the arthrodesis stem and to a longer one bridging the fracture. In one case a stem loosening was seen. This was as well addressed by the use of a longer stem. Knee arthrodesis by a modular non cemented system is a god alternative in order to preserve the weight-bearing lower extremity. The complication rate is rather high due to the fact, that this procedure presents the final alternative to do so in patients, who are in extremis in terms of a long lasting aggressive peri-arthroplasty infection the lead to massive destruction of the soft tissue around the knee and a significant loss of function

Determine if debridement, rather than staged revision is a more effective strategy in some patient subgroups with infected arthroplasty. We compiled a database comprising 154 proven infected knee replacements and 144 infected hip replacements in Christchurch over the last 10 years. This has given us the largest series in the literature. Cross referencing this database with the joint registry enabled us to compare the treatment of both acute and chronic infection in hip and knee arthroplasty with regard to both functional outcome and re-revision rate. Patients treated with debridement had no statistically significant difference in re-revision rate or functional score when compared with patients undergoing staged revision. Orthopaedic surgeons justifiably aim to eradicate infection in arthroplasty patients. A prosthesis retaining management strategy may be justifiable, especially in certain patient groups in whom multiple operations are best avoided

Background. The diagnosis of Periprosthetic Joint Infection (PJI) is a considerable challenge in total joint arthroplasty. The mainstay for diagnosis of PJI is a combination of serological markers, including C-reactive protein (CRP), along with joint aspirate for white cell count, differential and culture. The aim of this study was to examine the use of synovial fluid CRP in the diagnosis of PJI. Material & Methods. Synovial fluid samples were collected prospectively from patients undergoing primary and revision knee arthroplasty. Samples were assessed for CRP, cell count and differential. Three groups were analyzed; those undergoing primary knee arthroplasty, aseptic knee arthroplasties and infected arthroplasties. Demographic data, along with associated medical co-morbidities, were collected,. Statistical analysis was performed. Synovial fluid CRP was correlated with serum CRP values. Sensitivity and specificity were calculated. Results. 50 synovial fluid samples were collected from 50 patients. Synovial fluid CRP was 0.3 +/− 0.4 in native knees, 0.2 +/− 0.5 in aseptic knee arthroplasties, 4.3+/−4.1 in patients with infected knee arthroplasties. Synovial fluid CRP was significantly higher in septic total knee arthroplasties by comparison to both aseptic total knees (p< 0.001) and native knees (p=0.006). The specificity was 100% and the sensitivity was 89% at a CRP of 1. Conclusion. While this is preliminary data, synovial fluid CRP was found to be significantly elevated in patients with infected total knee arthroplasties. This test is easily performed under routine hospital laboratory conditions without specific, expensive assays. We believe synovial CRP assay holds great promise as a new, potentially low-cost, diagnostic marker for PJI

Aim. Antibiotic loaded spacers are often used during a two-stage exchange for periprosthetic joint infections (PJI) both for its mechanical properties and as a means for local antibiotic delivery. The main goal of this study is to compare the rate of positive cultures during reimplantation with the use of different antibiotic loaded spacers: aminoglycoside only vs. combined glycopeptide/aminoglycoside vs. combined glycopeptide/carbapenem/aminoglycoside. Method. We retrospectively evaluated every two-stage exchange procedures for infected hip/knee arthroplasty between 2012–2018. Microbiological findings in the first and second stage were registered as well as the type of spacer and antibiotic(s) used. Cases in whom no cultures were obtained during reimplantation and cases without sufficient data on antibiotic(s) used in cement spacers were excluded. Results. Fifty-four cases were included (20THA and 34TKA), with an overall rate of positive cultures during reimplantation of 18.5% (10/54). The rate of positive cultures was statistically significant higher among spacers with monotherapy with aminoglycoside compared to spacers with combined antibiotic therapy- 35.7% (5/14) vs. 12.5% (5/40) respectively(p<0.05). Comparing those with combined glycopeptide/aminoglycoside (2/19) with triple glycopeptide/carbapenem/aminoglycoside therapy (3/21) there was no significant difference. Microorganisms present during the second stage were mostly staphylococci (coagulase-negative in four cases, S.aureus in three), Corynebacterium striatum, Enterococcus faecalis, C.albicans in one case each. In most cases (8/10), the isolated microorganism was the same as the first stage and was resistant to the antibiotic(s) used in the spacer in seven cases. Failure rate with the need for subsequent surgery was significantly higher at 60% (6/10) in cases with positive cultures at reimplantation compared to 4.5% (2/44) for those with negative cultures during reimplantation(p=0.0005). Conclusions. It has recently been suggested that adding a glycopeptide to the spacer may be advantageous when compared to spacers with aminoglycoside monotherapy, as it will produce significantly lower rates of positive cultures during reimplantation which have been shown to increase the risk of subsequent failure as is the case in our study. Local unavailability of obtaining powder aminoglycosides has driven us to manually add high doses of vancomycin and meropenem to commercially available low-dose gentamicin cement in many of our spacers and they seem to to perform just as well as commercially available vancomycin/gentamicin combination. Although many other variables not considered in this study may influence the rate of positive cultures during the second stage (quality of initial debridement, systemic antibiotic therapy, etc.), we believe these results portrait a sufficiently accurate picture of clinical results with the use of different spacers

Infection after knee arthroplasty is a devastating complication. Our aim is to present our outcomes of treating infected knee replacements at a tertiary referral centre. We performed a consecutive, retrospective case series of all revision knee arthroplasty for infection between January 2006 and December 2008. Case notes were reviewed and data collated on the date and institution of primary arthroplasty, procedures undertaken at our institution, microbiology and bone loss post first stage, serological markers (C-reactive protein, ESR) prior to second stage and outcome. During this three year period we performed 430 knee revision operations. 51 were in the presence of deep chronic infection. 90% were referred from other hospitals. Overall infection was successfully eradicated in 69%. Nineteen patients underwent repeat two-stage and overall eleven (58%) patients had successful eradication of infection with multiple two-stages. Of these 47% had F3/T3, the highest grading of Anderson Orthopaedic Research Institute bone loss indicating no metaphyseal bone. A further 12% had bicondylar deficiency on the tibia and no femoral metaphyseal bone (F3/T2b). Multidrug resistance present in 69% and 47% were infected with multiple organisms. All members of the unsuccessful outcome group had at least one multidrug resistant organism compared to 43% in the successful cohort (P=0.0002). Multiple organisms are associated with an unsuccessful outcome (P=0.056). Serological markers were not significantly different between the successful and unsuccessful outcome groups. Where the referring hospital had attempted revision and failed, the chance of eradicating infection dropped from 75% to 58% and the rate of above knee amputation was twelve times higher (3% vs. 36%). Custom constrained, rotating hinge prostheses enable aggressive soft tissue debridement including ligaments. Successful two-stage requires a multidisciplinary approach including tissue viability nurses, microbiologists and plastic surgeons. Where units lack revision expertise this series suggests early referral increases the chance of limb salvage

Aims

Elective surgery has been severely curtailed as a result of the COVID-19 pandemic. There is little evidence to guide surgeons in assessing what processes should be put in place to restart elective surgery safely in a time of endemic COVID-19 in the community.