Objectives. The optimal protocol for antibiotic loading in the articulating cement spacers for the treatment of prosthetic joint infection (PJI) remains controversial. The objective of the present study was to investigate the effectiveness of articulating cement spacers loaded with a new combination of antibiotics. Methods. A retrospective cohort study involving 114 PJI cases treated with implantation of an articulating cement spacer between 2005 and 2016 was performed. The treatment outcomes of the conventional protocol (i.e. gentamicin and vancomycin (GV protocol)) were compared with those reported using the sophisticated antibiotic-loading protocol (i.e. vancomycin, meropenem, and amphotericin (VMA protocol)). Results. There were 62 and 52 PJI cases treated with the GV and VMA protocols, respectively. Antimicrobial susceptibility testing revealed that 22/78 of all isolates (28.2%) in this series were resistant to gentamicin, whereas there were no vancomycin-, meropenem-, or amphotericin-resistant strains. The overall infection recurrence rates were 17.7% (11/62) and 1.9% (1/52), respectively (p = 0.006). In patients with a negative preoperative culture, there was no infection recurrence reported in the VMA cohort (0/45 (0%) vs 10/54 (18.5%) in the GV cohort; p = 0.002). Multivariate analysis indicated that the VMA protocol correlated with a decreased risk of infection recurrence compared with the GV protocol (p = 0.025). Conclusion. The sophisticated VMA protocol for the loading of antibiotics in articulating cement spacers, as part of a two-stage exchange, was associated with a reduced rate of infection recurrence. This proposed protocol appears to be safe and effective, especially in patients with negative culture results prior to the first-stage operation. Cite this article: Bone Joint Res 2019;8:526–534

Objectives. The optimal protocol for antibiotic loading in the articulating cement spacers for the treatment of prosthetic joint infection (PJI) remains controversial. The objective of the present study was to investigate the effectiveness of articulating cement spacers loaded with a new combination of antibiotics. Methods. A retrospective cohort study involving 114 PJI cases treated with implantation of an articulating cement spacer between 2005 and 2016 was performed. The treatment outcomes of the conventional protocol (i.e. gentamicin and vancomycin (GV protocol)) were compared with those reported using the sophisticated antibiotic-loading protocol (i.e. vancomycin, meropenem, and amphotericin (VMA protocol)). Results. There were 62 and 52 PJI cases treated with the GV and VMA protocols, respectively. Antimicrobial susceptibility testing revealed that 22/78 of all isolates (28.2%) in this series were resistant to gentamicin, whereas there were no vancomycin-, meropenem-, or amphotericin-resistant strains. The overall infection recurrence rates were 17.7% (11/62) and 1.9% (1/52), respectively (p = 0.006). In patients with a negative preoperative culture, there was no infection recurrence reported in the VMA cohort (0/45 (0%) vs 10/54 (18.5%) in the GV cohort; p = 0.002). Multivariate analysis indicated that the VMA protocol correlated with a decreased risk of infection recurrence compared with the GV protocol (p = 0.025). Conclusion. The sophisticated VMA protocol for the loading of antibiotics in articulating cement spacers, as part of a two-stage exchange, was associated with a reduced rate of infection recurrence. This proposed protocol appears to be safe and effective, especially in patients with negative culture results prior to the first-stage operation. Cite this article: Bone Joint Res 2019;8:526–534

Objectives. Vancomycin and fosfomycin are antibiotics commonly used to treat methicillin-resistant Staphylococcus aureus (MRSA) infection. This study compares the in vitro inhibitory effects against MRSA of articulating cement spacers impregnated with either vancomycin or fosfomycin. Methods. Vancomycin-impregnated articulating cement spacers and fosfomycin-impregnated articulating cement spacers were immersed in sterile phosphate-buffered saline (PBS) solutions and then incubated. Samples were collected for bioactivity evaluation. The aliquots were tested for MRSA inhibition with the disc diffusion method, and the inhibition zone diameters were measured. The inhibition zone differences were evaluated using the Wilcoxon Rank Sum Test. Results. The vancomycin group had significantly larger inhibition zones than the fosfomycin group from day three through to completion of the fourth week of incubation (p < 0.001). The vancomycin group exhibited a MRSA inhibition zone up to four weeks but the fosfomycin group showed an inhibition zone for only three days and after that did not show the the potential to inhibit MRSA. Conclusion. This in vitro study found that the inhibitory effect of vancomycin-impregnated articulating cement spacers against MRSA outperformed fosfomycin-impregnated articulating cement spacers. Further comparing our results to other published reports suggests there might be a limitation of the disc diffusion bioassay to show a large inhibitory zone in a high concentration of a highly soluble antibiotic. Cite this article: V. Yuenyongviwat, N. Ingviya, P. Pathaburee, B. Tangtrakulwanich. Inhibitory effects of vancomycin and fosfomycin on methicillin-resistant Staphylococcus aureus from antibiotic-impregnated articulating cement spacers. Bone Joint Res 2017;6:132–136. DOI: 10.1302/2046-3758.63.2000639

We present a series of 48 patients with infected total knee replacements managed by the use of articulating cement spacers and short-term parenteral antibiotic therapy in the postoperative period. All patients had microbiological and/or histological confirmation of infection at the first stage of their revision. They all underwent re-implantation and had a mean follow-up of 48.5 months (26 to 85). Infection was successfully eradicated in 42 of the 48 patients (88%). Six had persistent infection which led to recurrence of symptoms and further surgery was successful in eliminating infection in four patients. These rates of success are similar to those of other comparable series. We conclude that protracted courses of intravenous antibiotic treatment may not be necessary in the management of the infected total knee replacement. In addition, we analysed the microbiological, histological and serological results obtained at the time of re-implantation of the definitive prosthesis, but could not identify a single test which alone would accurately predict a successful outcome

The common recommended treatment for infected total hip replacement is two-staged exchange including removal of all components. However, removal of well-fixed femoral stems can result in structural bone damage. We recently reported on an alternative treatment of partial two-stage exchange used in selected cases, in which a well-fixed femoral stem was left and only the acetabular component removed, the joint space was debrided thoroughly, an antibiotic-laden polymethylmethacrylate spacer was moulded using a bulb-type syringe and placed in the acetabulum, intravenous antibiotics were administered during the interval, and delayed re-implantation was performed. In 19 patients treated with this technique from January 2000 to January 2011, 89% were free of infection at a mean follow-up of four years (2 to 11). Since then, disposable silicone moulds have become available to fabricate spacers in separate femoral and head units. The head spacer mould, which incorporates various neck taper adapter options, greatly facilitates the technique of partial two-stage exchange. We report our early experience using disposable silicone head spacer moulds for partial two-stage exchange in seven patients with infected primary hip replacements.

Cite this article: Bone Joint J 2014;96-B(11 Suppl A):66–9

Aims. To explore the clinical efficacy of using two different types of articulating spacers in two-stage revision for chronic knee periprosthetic joint infection (kPJI). Methods. A retrospective cohort study of 50 chronic kPJI patients treated with two types of articulating spacers between January 2014 and March 2022 was conducted. The clinical outcomes and functional status of the different articulating spacers were compared. Overall, 17 patients were treated with prosthetic spacers (prosthetic group (PG)), and 33 patients were treated with cement spacers (cement group (CG)). The CG had a longer mean follow-up period (46.67 months (SD 26.61)) than the PG (24.82 months (SD 16.46); p = 0.001). Results. Infection was eradicated in 45 patients overall (90%). The PG had a better knee range of motion (ROM) and Knee Society Score (KSS) after the first-stage revision (p = 0.004; p = 0.002), while both groups had similar ROMs and KSSs at the last follow-up (p = 0.136; p = 0.895). The KSS in the CG was significantly better at the last follow-up (p = 0.013), while a larger percentage (10 in 17, 58.82%) of patients in the PG chose to retain the spacer (p = 0.008). Conclusion. Prosthetic spacers and cement spacers are both effective at treating chronic kPJI because they encourage infection control, and the former improved knee function status between stages. For some patients, prosthetic spacers may not require reimplantation. Cite this article: Bone Joint Res 2024;13(6):306–314

Aims. Our objective is to describe our early and mid-term results with the use of a new simple primary knee prosthesis as an articulating spacer in planned two-stage management for infected knee arthroplasty. As a second objective, we compared outcomes between the group with a retained first stage and those with a complete two-stage revision. Methods. We included 47 patients (48 knees) with positive criteria for infection, with a minimum two-year follow-up, in which a two-stage approach with an articulating spacer with new implants was used. Patients with infection control, and a stable and functional knee were allowed to retain the initial first-stage components. Outcomes recorded included: infection control rate, reoperations, final range of motion (ROM), and quality of life assessment (QoL) including Western Ontario and McMaster Universities osteoarthritis index, Knee Injury and Osteoarthritis Outcome Score, Oxford Knee Score, 12-Item Short-Form Health Survey questionnaire, and University of California Los Angeles (UCLA) activity score and satisfaction score. These outcomes were evaluated and compared to additional cohorts of patients with retained first-stage interventions and those with a complete two-stage revision. Mean follow-up was 3.7 years (2.0 to 6.5). Results. Eight knees failed directly related to lack of infection control (16%), and two patients (two knees) died within the first year for causes not directly related, giving an initial success rate of 79% (38/48). Secondary success rate after a subsequent procedure was 91% (44/48 knees). From the initially retained spacers, four knees (22%) required a second-stage revision for continuous symptoms and one (5%) for an acute infection. There were no significant differences regarding the failure rate due to infection, ROM, and QoL assessment between patients with a retained first-stage procedure and those who underwent a second-stage operation. Conclusion. Our protocol of two-stage exchange for infected knee arthroplasties with an articulating spacer and using new primary knee implants achieves adequate infection control. Retained first-stage operations achieve comparable results in selected cases, with no difference in infection control, ROM, and QoL assessment in comparison to patients with completed two-stage revision surgery. Cite this article: Bone Joint J 2020;102-B(7):852–860

Surgical treatment of Hip PJI by resection of the infected implants and tissue and placement of a “spacer” which elutes antibiotic via antibiotic loaded cement is an accepted treatment option. There is some controversy over whether this “spacer” should be articulating or static. Proponents of the articulating option argue that there is improved function and maintenance of the soft tissue envelop. Critics have suggested that additional biomaterials may compromise eradication of infection. This study compares our results of the 2 treatment options. A review of our institutional PJI database between 2016 and 2021 identified 87 patients who were treated with resection arthroplasty for unilateral total hip PJI. The cohort was analyzed for demographics and type for surgery, as well as medical comorbidities, survivorship, and treatment success. 44 patients were female, the mean age of all patients was 62. 44 patients were treated with Articulating apacers, and 43 patients treated with static spacers. There was no significant difference between ASA or Elixhauser score, and no significant difference between mortality or treatment failure. This study did not show any difference between the patients who receive static spacers, from those who received articulating spacers, and deomstrated similar treatment success rates. From this data there does not appear to be any difference in success rates between those patients that were treated with static spacers and those that were treated with articulating spacers

Introduction. Two-stage revision surgery remains the gold standard as treatment for periprosthetic hip infections. The purpose of this study was to determine the rate of infection eradication after two-stage revision hip arthroplasty in patients treated with intraoperatively surgeon-molded articulating spacers as well as to foreshadow the future economical impact of these articulating antibiotic spacers to those commercially available. Methods. Thirty-five patients who underwent two-stage revision hip arthroplasty due to chronic periprosthetic infection between 2003–2014 were followed clinically and radiographically an average of 4.9 years postoperatively [2.2–9.2]. 17 male and 18 female patients with a mean age of 62 [34–82] had articulating spacers, made in the operating room, inserted at the first stage. [The overall expense of the custom-made antibiotic spacers and the commercially available spacers was calculated and compared using a student t test.]. Results. Thirty-one patients (91%) had no clinical or radiographic signs of infection at the time of most recent follow-up. There were no periprosthetic femur fractures and two (6.0%) had a dislocation of hip spacer prior to the second stage surgery. After reimplantation, three patients (9.0%) suffered dislocations of the prosthetic hip, with one of those patients undergoing a second dislocation of the previously reduced hip. [The antibiotic articulating hip spacer manufactured intraoperatively cost $2,712 as compared to commercially available injectable molds $4,619 (p<0.05) and prefabricated spacers $3,820 (p<0.05).]. Conclusions. Patients treated using intraoperatively molded articulating spacers had similar infection eradication rates and outcomes compared to previously reported commercially available articulating spacers1. In the era of cost containment and surgical bundles, surgeon-made articulating spacers should be considered in the first stage of periprosthetic infections. The adjustment in treatment could equate to a national savings of over $12 million annually

The rate of periprosthetic joint infections (PJI) after primary total hip arthroplasty (THA) is approximately 1%. As the number of THAs performed each year continue to increase (550,000 by 2030), a corresponding increase in the number of hip PJI cases is likely to occur. A chronic deep infection may be treated by either chronic suppression, irrigation and debridement, single-stage exchange, or two-stage exchange. In the United States, the gold standard for chronic PJI continues to be a two-stage exchange. The benefit of an antibiotic impregnated cement is that they produce higher local concentrations of antibiotics than systemic intravenous administration. Hip spacers may be either static or articulating. Static spacers are reserved for cases of massive acetabular bone loss in which an articulating spacer is not feasible. A static spacer consists of a block of antibiotic cement in the native acetabulum and antibiotic coated rod in the femoral canal. Limb shortening, loss of soft tissue planes, and disuse osteopenia and muscle atrophy are all limitations of static spacers. In contrast, articulating spacers fulfill the goals of the interim construct during two-stage exchange which is to enhance eradication of the infecting organism through drug elution, to maintain limb length, to facilitate exposure during revision surgery, and to improve functional mobilization. Articulating spacers may be divided into three general categories based on method of spacer creation: Handmade custom spacers, prefabricated spacers, custom molded spacers (hemiarthroplasty molds and molded stem with cemented all-polyethylene cup). Handmade custom spacers are usually created with K-wire or rush rods coated with antibiotic cement. Handmade spacers are relatively simple to make, they are economical, and the amount and type of antibiotics incorporated can be customised for the infecting organism. Commercially available hemiarthroplasty spacers can be either prefabricated (Spacer G, Exactech, Gainesville. FL) or made intraoperatively (Stage One, Zimmer Biomet, Warsaw, IN) are available in several head and stem sizes. The advantage of prefabricated spacers is that they do not require additional time to mold in the operating room. The downside of prefabricated spacers is that the antibiotic concentration and type is predetermined. A custom molded stem with cemented all-polyethylene cup can be made with off the shelf implants or used as part of a commercially available spacer (PROSTALAC, DePuy Synthes, Warsaw, IN). A common antibiotic/cement combination includes Tobramycin (3.6 g/40 g of cement) and vancomycin (1.5 g/40 g of cement). In all of these spacer constructs, the principles of using a high-elution cement mixed without a vacuum and with high doses of heat stable antibiotics are consistent. Tobramycin works synergistically to improve Vancomycin elution properties and is usually added in higher doses. Overall infection eradication is similar between all categories of spacers and range between 90–97%. Complications after placement of an articulating spacer are often specific to the type of spacer used. Handmade spaces that have K-wires for support are at risk for spacer cement fracture. Spacer dislocation is also a common complication in up to 15% of cases with all types of spacers. In addition, periprosthetic fractures can occur postoperatively in up to 10% of patients. Overall, despite this complication profile, articulating antibiotic spacers have excellent rates of infection eradication and offer improved mobilization in the interim two stage period and reduce operative time, complexity, and morbidity during reimplantation

Introduction. Our objective is to describe early and midterm results with the use of a new knee prosthesis as an articulating spacer in planned two-stage management for infected total knee arthroplasty. As a second objective, we compared outcomes between the group with a retained first stage and those with a completed 2-stage revision. Methods. Forty-seven patients (48 knees) from January 2012 and November 2017 underwent a 2-stage exchange with an articulating spacer with new implants was used for a chronic knee periprosthetic joint infection with a mean follow-up of 3.7 years (2–6.5 years). The most frequently identified infecting organism was MSSA (31%), MRSA (21%) or MRSE (20%). At the first stage, a new PS femoral component and a new all-polyethylene posterior stabilized (PS) tibial component or a standard PS tibial liner were cemented with antibiotic-cement, typically 3.6 gm tobramycin and vancomycin 1.5 gm. IV antibiotics for six weeks were administered. The planned reimplantation was at 3 months, but ninetteen spacers (14 all poly tibias and 5 tibial liner) were retained for over 12 months. Postoperative assessment included knee range of motion (ROM), quality of life (QOL) scores (SF-12, WOMAC, KOOS, Oxford, and UCLA scores), and a satisfaction scale from 0–100%. Results. Of the 48 knees, 8 failed due to lack of infection control, and 2 died within the first year for medical reasons (4%), giving a failure rate of 17% (8/46). One of these knees was not revised due to poor medical status. Of the remaining 7, 2 had a repeat 2-stage exchange, one a single stage revision and 4 irrigation and debridement with retained implants. All 7 had a successful outcome with infection control after this, leaving a permanent failure rate of 2% (1/46). Five of the 19 knees with initially retained implants were revised to a second stage after 12 months for continued pain or instability (1/14 all poly tibia and 4/5 PS liner). There were no significant differences in final range of motion or QOL scores between patients with a retained first stage procedure and those who underwent a second stage operation. Also, there was no statistically significant difference in the initial failure rate due to infection between patients with a complete 2-stage revision and those with a retained first stage (19% (6/31) vs. 14% (2/14), respectively; p=0.613). Conclusions. When an all poly tibial implant is used a spacer in two-stage exchange arthroplasty, it may be retained for over 12 months, with no difference in infection control, range of motion, and quality of life assessment to patients with complete 2-stage revision surgery. With this technique, the second stage may be delayed in patients who are doing well, and may never need to be revised, hence we propose the new term “one-and-a-half stage exchange”

The infected TKA is one of the most challenging complications of knee surgery, but spacers can make them easier to treat. An articulating spacer allows weight bearing and range of motion of the knee during rehabilitation. This spacer is made using antibiotic-impregnated bone cement applied to the tibial and femoral implants. For our purpose, 4.8g powdered tobramycin is mixed with 2gm vancomycin and one batch of antibiotic. Cement is applied early to the components, but applied late to the femur, tibia, and patella to allow molding to the defects and bone without solid adherence to bone. Patients have tailored intravenous antibiotic therapy for 6 weeks for treatment of various gram-positive and gram-negative organisms. At 10–12 weeks patients are revised to a cemented revision total knee arthroplasty using standard cementing techniques. From our experience, range of motion before reimplantation was 5 – 90 degrees. Follow-up averaged 73 months for fifty patients with 90% good to excellent results; 10% had a recurrence of infections. Use of an articulating spacer achieves soft tissue compliance, allows for ease of re-operation, reduced postoperative pain, improved function, and eradicates infection equal to standards reported in the literature

In recent years articulating cement spacers have been used to treat infected knee arthroplasty. The aim has been to better maintain tissue planes and joint mobility thereby improving second stage re-implantation surgery. Two groups of patients treated for infected knee arthroplasty were reviewed. Twenty-six patients with articulating and forty patients with static antibiotic-impregnated methyl-methacrylate spacers were compared. The articulating spacers demonstrated easier surgical exposure at second stage and improved range of knee motion after re-implantation. There was no compromise in the rate of infection eradication with articulating spacers. Bone loss at revision was independent of spacer type. To compare the results of patients treated with articulating versus static antibiotic-impregnated spacers for infected knee arthroplasty. Articulating cement spacers facilitate re-implantation surgery by maintaining tissue planes and joint mobility without compromising joint stability or eradication rate of infection. Patients demonstrate better range of motion and less complications related to the extensor mechanism with the articulated spacer. Antibiotic impregnated methyl-methacrylate spacers have become a mainstay in two-stage revision arthroplasty for sepsis. It is thought that articulating cement spacers facilitate prosthesis re-insertion by better maintaining tissue planes and joint mobility between stages. In the articulating group fewer extensile exposure methods were required at second stage prosthesis reimplantation (19% vs 36 %). No tibial tuberosity osteotomies have been required since using the articulating spacer. The articulating group demonstrated a significantly improved range of flexion compared to the static group(106 vs 97 degrees- p=0.045) and had fewer patients with significant loss of extension or quadriceps lag. Eradication of infection was improved in the articulating group (92% vs 82%) but at shorter average follow-up. The need for augments and stabilized prostheses at revision surgery as a measure of bone loss was no different between the groups but was related to the number of prior surgical procedures. Twenty-six patients treated with articulating spacers were compared to a matched consecutive group of forty patients treated with static spacers. Minimum follow-up was twelve months from second stage re-implantation (average twenty-two months articulating, forty months static). Funding: No direct funding from any commercial source has been received for this study. The primary author’s fellowship position is partially funded by Smith and Nephew Richards Inc

In recent years articulating cement spacers have been used to treat infected knee arthroplasty. The aim has been to better maintain tissue planes and joint mobility thereby improving second stage re-implantation surgery. Two groups of patients treated for infected knee arthroplasty were reviewed. Twenty-six patients with articulating and forty patients with static antibiotic-impregnated methyl-methacrylate spacers were compared. The articulating spacers demonstrated easier surgical exposure at second stage and improved range of knee motion after re-implantation. There was no compromise in the rate of infection eradication with articulating spacers. Bone loss at revision was independent of spacer type. To compare the results of patients treated with articulating versus static antibiotic-impregnated spacers for infected knee arthroplasty. Articulating cement spacers facilitate re-implantation surgery by maintaining tissue planes and joint mobility without compromising joint stability or eradication rate of infection. Patients demonstrate better range of motion and less complications related to the extensor mechanism with the articulated spacer. Antibiotic impregnated methyl-methacrylate spacers have become a mainstay in two-stage revision arthroplasty for sepsis. It is thought that articulating cement spacers facilitate prosthesis re-insertion by better maintaining tissue planes and joint mobility between stages. In the articulating group fewer extensile exposure methods were required at second stage prosthesis reimplantation (19% vs 36 %). No tibial tuberosity osteotomies have been required since using the articulating spacer. The articulating group demonstrated a significantly improved range of flexion compared to the static group(106 vs 97 degrees- p=0.045) and had fewer patients with significant loss of extension or quadriceps lag. Eradication of infection was improved in the articulating group (92% vs 82%) but at shorter average follow-up. The need for augments and stabilized prostheses at revision surgery as a measure of bone loss was no different between the groups but was related to the number of prior surgical procedures. Twenty-six patients treated with articulating spacers were compared to a matched consecutive group of forty patients treated with static spacers. Minimum follow-up was twelve months from second stage re-implantation (average twenty-two months articulating, forty months static). Funding: No direct funding from any commercial source has been received for this study. The primary author’s fellowship position is partially funded by Smith and Nephew Richards Inc

The aim of this study was to measure intra-articular gentamicin levels at the 2. nd. stage revision following the use of an antibiotic impregnated articulating spacer. Infected total knee replacements are a cause of considerable morbidity often requiring revision in two stages. Rings of bone cement, cement moulds and spacer devices are available for use following the initial debridement and removal of infected metalwork. The availability of antibiotic impregnated articulating spacers are potentially attractive to achieve a high local dose of antibiotic and to maintain a good range of movement. Seven patients underwent a two stage revision of their total knee replacements. Following the initial debridement an antibiotic impregnated articulating spacer was cemented in place. At the 2. nd. stage revision a perioperative joint aspirate and blood sample was taken and gentamicin levels measured. The range of movement was assessed. The average gentamicin levels were 0.72mg/l (0.24 – 2.36mg/l). A good range of movement was maintained in all cases. At these levels the gentamicin would be therapeutic. Antibiotic impregnated articulating spacers possess several potential advantages to the revision knee surgeon by helping maintain the range of movement and provide local release of antibiotics. Their use should be considered in such cases

Background. The purpose of this multi-center, randomized clinical trial was to compare static and articulating spacers in the treatment of PJI complicating total knee arthroplasty TKA. Methods. 68 Patients treated with two-stage exchange arthroplasty were randomized to either a static (32 patients) or an articulating (36 patients) spacer. A power analysis determined that 28 patients per group were necessary to detect a 13º difference in range of motion between groups. Six patients were excluded after randomization, six died, and seven were lost to follow-up prior to two years. Results. Patients in the static group had a hospital length of stay that was one day greater than the articulating group (6.1 vs. 5.1 days; p=0.032); no other differences were noted perioperatively. At a mean 3.5 years (range, 2.0 to 6.4 years), 49 patients were available for evaluation. Mean motion arc in the articulating group was 113.0º compared to 100.2º in the static group (p=0.001). The mean Knee Society Score was significantly higher in the articulating cohort (79.4 vs. 69.8 points; p=0.043). Although not significantly different with the sample size studied, static spacers were associated with a greater need for an extensile exposure at the time of reimplantation (16.7% vs. 3.8%) and a higher rate of reoperation (33.3% vs. 12.0%). Conclusions. Articulating spacers provided significantly greater range of motion and better clinical outcomes scores. Static spacers also appeared to affect early postoperative rehabilitation, as evidenced by a longer hospital stay following removal of the infected implant and were associated with a trend towards a greater need for extensile exposures at the time of reimplantation. Further, while it has been commonly believed that static spacers would improve infection control, there was no difference in the failure rate secondary to reinfection and there was a trend towards higher risk of reoperation in patients who received a static spacer. When the soft tissue envelope allows and if there is adequate bony support, an articulating spacer is associated with improved outcomes. For figures, tables, or references, please contact authors directly

Aim. The primary endpoint of this study is to characterize the progression of bone defects at the femoral and tibial side in patients who sustained PJI of the knee that underwent two-stage revision with spacer implantation. In addition, we want to analyze the differences between functional moulded and hand-made spacers. Methods. A retrospective analysis of patients that underwent two-stage revision due to PJI of the knee between January 2014 and December 2021 at our institution. Diagnosis of infection was based on the criteria of the Muscoloskeletal Infection Society. The bone defect evaluation was performed intraoperatively based on the AORI classification. The basal evaluation was performed at the time the resection arthroplasty and spacer implantation surgery. The final evaluation was performed at the second-stage surgery, at the time of spacer removal and revision implant positioning. The differences between groups were characterized by using T-test student for continuous variables, and by using chi-square for categorical variables. A p-value < 0.05 was defined as significant. Results. Complete data of 37 two-stage TKAs revision were included in the study. An articulating moulded functional spacer was used in 14 (35.9%) cases, while a hand-made spacer was used in 23 (58.9%) cases. The average length of interval period (excluding the time for patients that retained the spacer) was 146.6 days. A bone defects progression based on the AORI classification was documented in 24 cases at the femoral side (61.6%), a bone defect progression was documented in 17 cases at the tibial side (43.6%), and a bone defect at both sides was documented in 13 cases (33.3%). A statistically significant greater bone defect progression at the tibial side was observed when hand-made spacers were used. A complication during the interval period was reported in five cases (12.8%) and postoperative complication was reported in 9 cases (23.1%). Conclusions. When comparing patients in which a functional articulating spacer was used, with patients in which static spacer was used, we reported a statistically significant reduced bone defect progression during the interval period at the femoral side only when moulded spacers were used. We observed a higher incidence of bone defect progression also at the tibial and both sides when hand-made spacers were used. This is the first study that documented the bone defect progression during two-stage revision of the knee, the results observed in this study are very encouraging

Background. Vancomycin and fosfomycin are antibiotic commonly used in Methicillin-resistant Staphylococcus aureus (MRSA) infection. This study compares the efficacy of articulating cement spacer implegnated with vancomycin and articulating cement spacer implegnated with fosfomycin to inhibit MRSA. Methods. Vancomycin implegnated articulating cement spacers and Fosfomycin implegnated articulating cement spacers were immersed in sterile phosphate buffered saline(PBS) and then incubated at 37 C. The samples were collected and change daily. Aliquots were tested for MRSA inhibition by disc diffusion method. The inhibition zones diameters were measured. Results. Vancomycin group showed an MRSA inhibition zone up to four weeks. However, Fosfomycin group showed inhibition zone in day 3 in some samples but after that no sample had the potential to inhibit MRSA. Conclusion. In this experiment. Vancomycin impregnated articulating cement spacers showed longer efficacy to inhibit MRSA when compared to Fosfomycin

The infected TKA is one of the most challenging complications of knee surgery, but spacers can make them easier to treat. An articulating spacer allows weight bearing and range of motion of the knee during rehabilitation. This spacer is made using antibiotic-impregnated bone cement applied to the tibial and femoral implant. For our purpose, 4.8g powdered tobramycin is mixed with 2g vancomycin and one batch of cement. Cement is applied early to the components, but applied late to the femur, tibia, and patella to allow molding to the defects and bone without solid adherence to bone. Patients have tailored intravenous antibiotic therapy for 6 weeks for treatment of various gram-positive and gram-negative organisms. At 10–12 weeks patients are revised to a cemented revision total knee arthroplasty using standard cementing techniques. From our experience, range of motion before reimplantation was 5 – 90 degrees. Follow-up averaged 73 months for fifty patients with 90% good to excellent results; 10% had a recurrence of infections. Use of an articulating spacer achieves soft tissue compliance, allows for ease of re-operation, reduced post-operative pain, improved function, and eradicates infection equal to standards reported in the literature

We present a case of multifocal infection involving the left total hip replacement and the right total knee replacement of a patient, further complicated by an infected non-union of a periprosthetic fracture of the right knee. This required the unique simultaneous management of both infection eradication and fracture stabilization in the knee. Both sites were treated with a 2-stage procedure, including the novel use of a stemmed articulating spacer for the right knee. This spacer was made combining a retrograde humeral nail, coated with antibiotic-impregnated cement, and a pre-formed articulating cement spacer. The patient was able to weight-bear on this spacer. The fracture went on to unite, and a second stage was performed with the use of stemmed prosthesis and augments. She remains infection free 2 years after the second stage operation. The use of a stemmed articulating knee spacer can facilitate infection eradication and fracture stabilization while preserving some motion and weight-bearing ability in the 2 stage management of an infected periprosthetic fracture of the knee