Introduction. Periprosthetic infection is a serious complication after total hip arthroplasty (THA). Two stage procedure using antibiotic-impregnated cement spacer is one of the treatments for late chronic infection after THA. We investigated the effects of two stage procedure on the infection control and the recurrence of infection after revision THA. Materials and Methods. We retrospectively reviewed a consecutive series of 10 cases of a periprosthetic infection after hip arthroplasty, including 3 THA and 7 bipolar hemiarthroplasty (BHA). They were treated with two stage procedure using antibiotic-impregnated cement spacer from 2004 to 2009. There were 4 women and 6 men with an average age of 68.4 years. The pathogens were methicilin-resistant Staphylococcus aureus (MRSA) in 3 cases, coagulase-negative Staphylococcus (CNS) in 2 cases, Enterococcus in 2 cases, Streptococcus in 2 cases, and unknown in 1 case. After removal of the prosthesis, extensive debridement was performed to remove infected tissues and residual cement. After irrigation with iodine solution, antibiotic-impregnated cement spacer was inserted with proximal cement fixation to prevent dislocation and fracture of the cement spacer. The antibiotics that were impregnated in the cement spacer were VCM in 8 cases, MEPM in 1 case, and CAZ in 1 case. Intravenous antibiotics were administrated for 3 weeks after this first stage surgery, and then oral antibiotics were administrated until C-reactive protein (CRP) rates became negative. After confirming the culture of joint fluid contained no pathogens, second stage revision surgery was performed. The average follow-up period after revision THA was 2.3 years. We investigated the period from first stage surgery to the day when CRP became negative, and to the day of second stage surgery. The incidence of recurrence of infection after revision THA was investigated. Results. The average period to negative CRP was 25 days, and that to the second stage surgery was 64 days. There has been no recurrent infection until now. Discussion. The antibiotics-impregnated cement spacer for the treatment of periprosthetic infection was introduced around 1990, and success rate of this technique was reported to exceed 90%. In our series, we experienced no recurrence of infection in spite of containing 3 MRSA cases and 2 CNS cases. The advantages of the antibiotics-impregnated cement spacer were to avoid soft tissue shortening and to allow patient to walk without weight bearing. We concluded that two-stage revision technique with antibiotics-impregnated cement spacer is an effective treatment for peripros

At first-stage revision surgery for infection of total knee arthroplasties, antibiotic-impregnated cement spacers are frequently implanted. Two types of cement spacers are commonly used, “static” and “articulating” cement spacers. Advocates of cement spacers state that they deliver high doses of antibiotics locally, increase patient comfort, allow mobility and provide joint stability. They also minimize contracture of collateral ligaments, thereby facilitating re-implantation of a definitive prosthesis at a later stage. The use of these cement spacers, however, are not without significant complications, including patella tendon injuries. We describe a series of three patients who sustained patella tendon injuries in infected total knee arthroplasties following the use of a static cement spacer at first-stage knee revision. The patella tendon injuries resulted in significant compromise to wound healing and knee stability requiring multiple surgeries. The mid-term function was poor with an Oxford score at 24 months ranging from 12–20. Based on our experience, we advise caution in the use of static cement spacer blocks. If they are to be used, we recommend that they should be keyed in the bone to prevent patella tendon injuries

Aims. 1. A two-stage revision remains as the “gold standard” treatment for chronically infected total knee arthroplaties. 2. Evaluate technical challenges in two stage revision. Materials and Methods. Fourteen septic knee prostheses were revised with a minimum follow-up of 2 years. Static antibiotic-impregnated cement spacers were used in all cases. Intravenous antibiotics according to sensitivity test of the culture were applied during patients’ hospital stay and continued up to 3 weeks. Oral antibiotics were given for another 3 weeks. Second-stage surgery was undertaken after control of infection with normal erythrocyte sedimentation rate and C-reactive protein values. Extensile techniques were used if needed and metallic augments were employed for bone loss in revision of both femur and tibia components. Results. The average interval between the first-stage resection and reimplantation was 7 weeks. Significant improvement was obtained with respect to visual analog scale pain and clinical and functional scores, and infection was not seen in all cases following a two-stage revision total knee arthroplasty. Radiographic evaluation showed suitable alignment without signs of mechanical loosening. Average range of movement achieved was 0 to 100 degrees. Most common knee infected was the second knee in bilateral cases. Conclusions. This technique is a reasonable procedure in chronic infection in knee arthroplasty and provides proper functional and clinical results. However, it sometimes requires extensile surgical approaches that could imply arduous surgeries. Metallic augments with cement less stems available in most of the knee revision systems are a suitable alternative to handle bone deficiencies, avoiding the use of bone allograft with its complications

Aim. In patients with bone sarcoma, placing mega prostheses in the proximal tibia is associated with high rates of infection. In studies with small numbers of patients and short follow-up periods, silver-coated mega prostheses have been reported to lead to reduced infection rates. To the best of our knowledge, this study is the largest one that has compared the infection rates with titanium versus silver-coated mega prostheses in patients treated for sarcomas in the proximal tibia. Method. The infection rate in 98 patients with sarcoma or giant cell tumour in the proximal tibia who underwent placement of a titanium (n = 42) or silver-coated (n = 56) mega prosthesis. *. was assessed, along with the treatments administered for any infection. Results. As the primary end point of the study, the rates of infection were 16.7% in the titanium group and 8.9% in the silver group, resulting in 5-year prosthesis survival rates of 90% in the silver group and 84% in the titanium group. Overall, seven of 56 patients in the silver group (12.5%) developed periprosthetic infection. Two patients became infected after revision surgery due to mechanical failure of the prosthesis. In the titanium group, one patient developed a periprosthetic infection after revision surgery (which was carried out in 50% of patients) due to a mechanical prosthetic failure, leading to an overall infection rate of 19.0% (eight of 42). Overall, nine of 12 (75%) periprosthetic infections in the two groups occurred within the first 2 years postoperatively, if later revision surgery due to mechanical failure was not necessary. Whereas three of the eight patients in the titanium group (37.5%) ultimately had to undergo amputation due to infected proximal tibia replacement, these mutilating surgical procedures were necessary in the silver group in only one patient (14.3%). In the titanium group, two-stage revision surgery with a temporary antibiotic-impregnated cement spacer was ultimately successful in four of eight patients (50.0%), but this procedure was necessary in only one patient in the silver group (14.3%). Conclusions. The use of silver-coated prostheses reduced the infection rate in a relatively large and homogeneous group of patients. In addition, less aggressive treatment of infection was possible in the group with silver-coated prostheses

BACKGROUND. High-dose antibiotic cement spacers are commonly used to treat prosthetic joint infections following knee arthroplasties. Several clinical studies have shown a high success rate with antibiotic cement spacers, however there is little data on the systemic complications of high-dose antibiotic spacers, particularly acute kidney injury (AKI). This study aims to determine the incidence of AKI and identify risk factors predisposing patients undergoing staged revision arthroplasty with antibiotic cement spacers. METHODS. A single-institution, retrospective review was used to collect and analyze clinical and demographic data for patients who underwent staged revision total knee arthroplasty with placement of an antibiotic-impregnated cement spacer from 2006 to 2016. A search was made through specific procedure (DRG) and diagnostic (CD) codes. Baseline descriptive data were collected for all patients including age, sex, medical comorbidities, type and quantity of antibiotics used in the cement spacer, pre- and postoperative hemoglobin (Hg), BMI, smoking status, peak creatinine levels, and random vancomycin levels. Acute kidney injury was defined as a more than 50% rise in serum creatinine from a preoperative baseline within 90 days postoperatively. RESULTS. A total of 54 staged revision TKA surgeries performed by 5 different surgeons between 2006 and 2016. The total incidence of AKI was 31% (n=17). There was a significant positive association between change in creatinine level and use of oral/intravenous antibiotics (p=0.03, Spearman's rho=0.33) and a significant positive association between AKI and the use of tobramycin cement (p=0.01, Spearman's rho=0.38). Factors that were not significantly associated with AKI include presence of preexisting hypertension (p = 0.26), hyperlipidemia (p = 0.83), coronary artery disease (p = 0.86), chronic kidney disease (p=0.56), and smoking status (p=.35). There was a trend towards increased risk of AKI in patients with diabetes mellitus (p= 0.12), however this was not significant. CONCLUSION. In single staged revision knee arthroplasty there is a significant association between acute kidney injury and type of oral/intravenous antibiotic used in the treatment. Both the use of intravenous vancomycin and tobramycin cement are independently associated with higher rates of AKI. Preexisting medical comorbidities are not independent risk factors for development of AKI. Serum creatinine and measurement of serum aminoglycoside and vancomycin levels should be performed after placement of an aminoglycoside-containing antibiotic cement spacer in a staged revision arthroplasty

Several risk factors can and should be addressed during first stage or spacer implantation surgery in order to minimize complications. Technical aspects as well as practical tips and pearls to overcome common nuisances such as spacer instability or femoral and acetabular bone loss will be discussed and shown with pictures. Total joint arthroplasty (TJA) is one of the most successful procedures in orthopaedics and excellent results are expected in virtually all cases. Periprosthetic joint infection (PJI) though unusual, is one of the most frequent and challenging complications after TJA. It is the third most common cause of revision in total hip replacement, responsible for up to 15% of all cases. In the past few years several improvements have been made in the management of an infected total hip prosthesis. Nevertheless it remains a challenging problem for the orthopaedic surgeon. Although numerous studies report favourable outcomes after one-stage revision surgery, two-stage has traditionally been considered as the gold standard for management of chronic infection. Two-stage exchange consists of debridement, resection of infected implants and usually temporary placement of an antibiotic-impregnated cement spacer before reimplantation of a new prosthesis. Spacers can be classified as static or articulating. The goals of using an articulating antibiotic loaded cement spacer are two-fold: to enhance the clearance of infection by local antibiotic therapy and dead-space management while maintaining joint function during treatment thus improving the functional outcome at reimplantation. Still, hip spacer implantation is not innocuous and there are several possible complications. Going forward, one must consider not just eradicating infection but also the importance of restoring function. In this regard using a mobile spacer adds an element of physiologic motion that both increases patient comfort between stages and facilitates re-implantation surgery. Conversely, mechanical complications are one of the major consequences of this preference. Be that as it may there are ways to minimize these problems. It is the surgeon responsibility to optimize mechanical circumstances as much as possible. I would like to thank Dr. Ricardo Sousa for his help with this work

Purpose. Infection following total knee arthroplasty is a devastating complication, requiring considerable effort on the part of the surgeon to eradicate the infection and restore joint function. Two-stage revision is the standard of care in the treatment of peri-prosthetic infection, using a temporary antibiotic-impregnated spacer between procedures. However, controversy remains concerning the use of static versus dynamic spacers, as well as the spacer material. The purpose of this study was to evaluate the clinical outcomes and complications of two-stage revision total knee arthroplasty in patients treated with a metal-on-polyethylene articulating spacer, as compared to those treated with a static antibiotic-impregnated cement spacer at the same centre. Method. Twenty-seven knees in patients with a mean age of 65 years (range, 40 to 80 years) were treated with two-stage revision of an infected total knee arthroplasty using a metal-on-polyethylene dynamic prosthetic spacer fixed with antibiotic-impregnated cement. Clinical outcomes were evaluated using maximum active knee range of motion, as well as modified Knee Society knee scores and incidence of re-infection at a minimum one-year follow-up. The results were compared to those achieved at similar follow-up in 10 patients treated with a static cement spacer. Demographic profile as measured by age and gender, and pre-operative Knee Society scores and range of motion were similar between the two groups. Results. At a mean of twenty-five months following re-implantation (range, 12 to 50 months), the patients treated with dynamic spacers had significantly higher Knee Society scores (mean 93 points, range 77 to 100 points) as compared to the group treated with static spacers (mean 76 points, range 59 to 89 points; p=0.039). Additionally, mean range of motion at final follow-up was substantially higher in the patients treated with dynamic spacers (mean 102 degrees, range 60 to 120 degrees versus mean 92 degrees, range 40 to 120 degrees). There was one re-infection in the dynamic spacer group (3.7%), in a patient whos clinical course was previously complicated by subluxation of the dynamic spacer between procedures. Otherwise, no gross loosening or fractures of the dynamic spacers were noted. Conclusion. The results of this study suggest that the use of a cemented metal-on-polyethylene dynamic prosthetic spacer at the time of two-stage revision knee arthroplasty is similarly effective in eradicating peri-prosthetic infections when compared to the use of a cemented static spacer, while providing better clinical outcomes at short-term follow-up. Additionally, this spacer design provides a degree of mobility and knee function between procedures that is unachievable with a static construct, and appears to eliminate the potential complication of spacer fracture associated with pre-formed cement implants. The authors await further data to confirm these findings at longer-term follow-up

Introduction. Infection following total joint arthroplasty is a major and devastating complication. After removal of the initial prosthesis, an antibiotic-impregnated cement spacer is inserted for approx. three months. Treatment is completed by a second stage revision arthroplasty. Up to now, spacers are produced from conventional bone cements that contain abrasive radio-opaque substances like zirconium dioxide or barium sulphate. As long as spacer wear products (cement particles containing these hard substances) are not fully removed during the final revision surgery they may enter the articulating surfaces of the revision implant leading to third body wear. In order to reduce the formation of reactive wear particles, a special cement (Copal(r) spacem) without abrasive zirconium dioxide or barium sulphate was developed. To date, no comparative tribological data for cement spacers have been published. Hence, we carried out a study on the wear properties of Copal(r) spacem (with and without gentamicin) in comparison to conventional bone cements (Palacos(r) R and SmartSet(r) GHV). Material and Methods. In order to assure reproducible forms of the femoral and tibial components, silicon rubber moulds were produced and filled with the respective cement. Force-controlled simulation was carried out on an AMTI knee simulator (Figure I). The test parameters were in accordance to ISO 14243-1 with a 50% reduced axial force (partial weight bearing). Tests were carried out at 37 °C in closed chambers filled with circulating calf serum. Tests were run for 240,000 cycles (representing the average step rate during 6-8 weeks) at a frequency of 1 Hz. For wear analysis, digital photographs of the spacer were taken at the beginning and at the end of the testing period. The areas of wear scars were measured by the means of a digital image processing software. Results. At the end of wear test none of the cement specimens showed cracks or failures. Pairwise comparison between the cement types revealed significant differences: Larger wear scars were observed for Copal(r) spacem compared to Copal(r) spacem + gentamicin (TUKEY test, p=0.025), whereas smaller wear scars were measured compared to Palacos(r) R (Figure 2), (TUKEY test, p<0.001). Copal(r) spacem + gentamicin showed the smallest wear scars with significance to all tested cements (Copal(r) spacem (TUKEY test, p=0.025), Palacos(r) R (TUKEY test, p<0.001), and SmartSet(r) GHV (TUKEY test, p=0.006). Discussion. Copal(r) spacem without and especially with gentamicin showed considerably smaller wear scar areas at 240,000 cycles compared to the well established cements Palacos(r) R and SmartSet(r) GHV (Figure 2). This finding is due to the soft calcium carbonate in Copal(r) spacem, which is clearly less abrasive against the surfaces of the sliding partners when compared to bone cements containing zirconium dioxide as radio contrast agents. Summarising these results, Copal(r) spacem provides a new and interesting approach to produce enhanced spacers with decreased wear. This concept should be further investigated from a mechanical, material-scientific and clinical point of view. Whether the favourable properties of Copal(r) spacem are applicable in order to improve survival of the revision implant needs to be investigated in a long-term study