Introduction:. Deep infection after total joint arthroplasty is a devastating complication with reported incidence of 1–3% with projection to increase to 6.8% by 2030. The direct costs of revision surgery due to septic failure are estimated at over $55,000 per case. Antibiotic-Loaded Bone Cement (ALBC) has been proposed as a preventive measure to decrease post-operative infection rates. Its efficacy has been compared with plain bone cement (PBC) in multiple studies. There has been no study to our knowledge examining its efficacy in “high risk” patients. The purpose of this study is to compare infection rates in three cohorts of patients: (1) all patients receiving only PBC, (2) all patients receiving only ALBC, and (3) only “high risk” patients receiving ALBC. Methods:. A standard cement protocol was instituted at our hospital for primary total knee arthroplasties (pTKA). From January 2000 to 2005 all pTKAs were performed with PBC. From February 2005 to May 2010, all pTKAs were performed with ALBC. From June 2010 to March 2012, all patients received regular bone cement unless they had previous diagnoses of rheumatoid arthritis, obesity, and/or diabetes mellitus. Our institutional joint registry was queried and the three cohorts' individual charts were retrospectively reviewed. Infection rates amongst cohorts were compared at 30 days, 6 months, and 1 year from index surgery date utilizing two sided proportion tests. Results:. A total of 3,292 consecutive primary TKAs with full follow up were included. Overall infection rate at one year for the entire study was 0.76%. There were 1,025 patients who received PBC, 1486 ALBC, and 781 in the risk stratified cohort. The 30-day infection rates for cohorts 1, 2, 3 were .0.29%, 0.20%, and 0.13% respectively. The 6-month infection rates for cohorts 1, 2, 3 were 0.39%, 0.54% and 0.38% respectively. The 1-year infection rate for cohorts 1, 2, 3 were 0.78%, 0.61%, and 0.64% respectively. The differences in infection rates between each cohort at all three time intervals were not statistically significant. Conclusions:. Antibiotic loaded bone cement does not significantly decrease infection rates for primary total knee arthroplasty. Even risk stratified usage of ALBC for “high risk” patients may be unnecessary and add undue costs to both the patient and hospital, without any appreciable benefit

The December 2023 Hip & Pelvis Roundup³⁶⁰ looks at: Early hip fracture surgery is safe for patients on direct oral anticoagulants; Time to return to work by occupational class after total hip or knee arthroplasty; Is there a consensus on air travel following hip and knee arthroplasty?; Predicting whether patients will achieve minimal clinically important differences following hip or knee arthroplasty; High-dose dual-antibiotic-loaded cement for hip hemiarthroplasty in the UK (WHiTE 8): a randomized controlled trial; Vitamin E – a positive thing in your poly?; Hydroxapatite-coated femoral stems: is there a difference in fixation?

Introduction. Infection after total hip arthroplasty is a severe complication. Controversies still exist as to the use of cemented or uncemented implants in the revision of infected THAs. Based on the data in the Norwegian Arthroplasty Register (NAR) we have studied this topic. Material and Methods. During the period 2002–2008 45.724 primary THAs were reported to NAR. Out of these 459 were revised due to infection (1,0%). The survival of the revisions with uncemented prostheses were compared to revisions with cemented prostheses with antibiotic loaded cement and to cemented prostheses with plain cement. Only prostheses with the same fixation both in acetabulum and in femur were included in the study. Cox-estimated survival and relative revision risks were calculated with adjustments for differences among groups in gender, type of surgical procedure, type of prosthesis, and age at revision. Results. 92 (23%) of all the revisions were performed with uncemented prostheses, 286 (71%) with cemented prostheses with antibiotic loaded cement, and 25 (6%) with plain cement. Compared to uncemented prostheses and with all reasons for revision as endpoint in the Cox-analyses, prostheses fixed with antibiotic loaded cement had 3.0 (1.4–6.3) times increased risk for re-revision (p=0.004) and prostheses with plain cement 1.9 (0.4–9.3) times increased risk (p=0.44). With infection as endpoint, prostheses with antibiotic loaded cement had 2.8 (1.2–6.4) times increased risk for re-revision (p=0.02) and prostheses with plain cement 2.6 (0.5–13.7) times increased (p=0.26). 77% of the re-revisions (48 of 60) were performed due to infection. Conclusion. Data in the Norwegian Arthroplasty Registry indicate that uncemented prostheses should be used in the revision of infected total arthroplasties

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. Periprosthetic joint infection (PJI) is a serious problem and requires great effort and cost for its treatment. Treatment options may vary from resection arthroplasty, retention of prosthesis with debridement, one stage revision and two stage revision with handmade antibiotic impregnated cement spacer or with prefabricated antibiotic loaded cement spacer. Two stage revision remains the gold standard for the treatment of periprosthetic joint infection after Total Hip Arthroplasty (THA). This study was aimed to find the efficacy and cost effectiveness of handmade antibiotic impregnated articulating cement spacer over commercially available prefabricated antibiotic loaded cement spacer for the treatment of deep PJI of hip prosthesis and to evaluate its functional outcome. Material and methods. A total of 23 PJI patients were enrolled in this prospective cohort study. In the two stages of revision, the first stage consisted of thorough debridement, implant removal and implantation of handmade articulating antibiotic impregnated cement spacer. The second stage surgery consisted of removal of cement spacer, thorough debridement and implantation of new prosthesis. All patients were followed for a period of 24 months. Results. A total of 23 patients (15 males and 8 females) underwent two stage revision arthroplasty for chronic periprosthetic joint infection. The mean age of the patient was 57 years. The handmade antibiotic impregnated cement spacer was retained for 16– 20 weeks. Common organism observed was coagulase negative staphylococci followed by Staphylococcus aureus. After an average follow up of 2 years, 20 patients with PJI remained clinically free of infection. In 2 patients there was recurrence of infection. Conclusion. We conclude that two stage revision by hand made cement spacer is successful in eradication of infection with satisfactory functional outcome. Furthermore, these handmade cement spacer are cost effective and their efficacy may be comparable to commercially available prefabricated spacer

Aim: To review the early complications associated with staged revision hip Arthroplasty utilising the Biomet antibiotic loaded cement spacer. Method: We report on 80 consecutive staged revision hip replacements using the Biomet antibiotic loaded cement system in our institution over 3 years (1999–2002), performed by three consultant surgeons, with a minimum 1 year follow up. Results: Our patients had an average age of 68 (range 48–90) years, with an equal sex distribution. The median time between the first and second stage was 147 (range 50–619) days. Fractures of the Biomet antibiotic loaded acrylic spacer occurred in 11% revisions when associated with an increase in time between stages and there was a 7% dislocation rate. Patients did not receive a revision prosthesis in 19% cases and had early recurrent sepsis following their two stage procedure in 6%. Three patients had a single episode of dislocation of their revision hip prosthesis within a month postoperatively. Two patients had a proximal DVT and one patient had a pulmonary embolus. The mortality within eight weeks was 7%, rising to 10% within a year. This may be related to patient sepsis and comorbidities or the energy expenditure required to mobilise following a first stage procedure that we have analysed. Conclusions: The risks of staged revision hip surgery for infection are substantial when considering the time involved, the energy expenditure required to mobilise following a first stage, the possibility of not achieving a revision hip prosthesis and the mortality rate. The Biomet antibiotic loaded cement system articulates and maintains soft tissue length in the majority of patients for the duration required between stages

Revision of infected TKA is one of the most challenging operation as the surgeon should achieve two goals, ie eradication of infection and restoration of function. For the eradication of infection, a minimum of two operations are needed in most of cases. First stage of revision is meticulous debridement and insertion of antibiotic loaded cement. During arthrotomy, thick fibrous and granulation tissues which is located in the suprapatella pouch, lateral site to the patella tendon and posterior joint space should be removed so as to get better exposure, to get rid of infection source and to get better functional result. During debridement, I use highly concentrated antibiotic saline (1 gm vancomycin in 10cc saline), for irrigation of the operation field. I also pack the opening of the medullary canal so as to prevent the debris from entering into the medullary canal. I use antibiotics with the ratio of 1:3. To reduce the dead space in the medullary canal I insert a dowel shaped antibiotic loaded cement spacer made from one pack of cement and fill the medullary canal. Thereafter two packs of cement are used to make a block to fill the gap between femur and tibia. The cement block should be large enough to cover the distal femur and proximal tibia so as not to cause bone defect and knee dislocation during walking. After first stage of operation, antibiotics are administered for 4∼8 wks until the CRP levels become normalized and clinical findings show no sign of infection. The 2. nd. stage of operation is planned when clinical and laboratory signs of infection subside. The decision whether to reimplant the prosthesis or not is based on the operation findings and polymorphonuclear cell count on frozen section. However operation findings are considered more important than the frozen section results for reimplantation. If operative findings are clean, I do reimplanation even though the polymorphonuclear cell count is more than 5 on high power field(hpf) on frozen section. I have adopted numbering system to take specimen. Number 1 is specimen from suprapatella pouch, No 2 is that from gap between the femur and tibia, No 3 is that from femoral intramedullary canal, No 4 is that from tibial intramedullary canal, and No 5 is that from most unhealthy site. In a retrospective analysis of 16 cases which received reimplantation despite of the prescence of more than five polymorphonuclear cells on intra-operative frozen sections, none of the cases had recurrence of infection at a final follow up of 2 years. The femoral medullary canal was the most prevalent site for higher polymorphonuclear cell count. In conclusion, indication is the first step for successful reimplantion. Two stage revision is recommended and meticulous debridement is utmost important in first stage operation. Block type antibiotic loaded cement is sufficient for a good result. Clinical, laboratory and operative findings are more important than polymorphonuclear cell count on frozen section to decide reimplantation. I propose numbering system of the specimen site for frozen section, just as in tumor surgery

Aim. Aim was to compare revision rates when using single versus dual antibiotic loaded cement (ABLC) in hip fracture arthroplasty and aseptic revision hip or knee arthroplasty using data from the Dutch national joint registry (LROI). Methods. All primary cemented (hemi-)arthroplasties for acute hip fractures and cemented aseptic hip or knee revision arthroplasties, were incorporated in 3 datasets. All registered implants between 2007 and 2018 were included (minimum 2 years follow-up). Primary end-point was subsequent revision rates for infection and for any reason in the single and dual ABLC groups. Cumulative crude incidence of revision was calculated using competing risk analysis. Results. A total of 22,308 hip fracture arthroplasties, 2,529 hip revision and 7,124 knee revision arthroplasties were registered and analyzed in the study period. The majority of hip fracture patients (97.1%) was treated with single ABLC. For hip and knee revision arthroplasties dual ABLC was used in 33.8% and 25.7%. The revision rate for infection in the fracture arthroplasty group was not different between groups (0.5% versus 0.8%, p=0.27). The re-revision rate following hip or knee revision based on single versus dual ABLC was not different between groups (3.2% versus 2.8%, p=0.82 for hip revision and 1.8% versus 2.5%, p=0.36 for knee revision). In addition, the re-revision rate for any reason was not different in all three datasets. The crude cumulative revision and re-revision rates for any reason based on single ABLC versus dual ABLC showed no differences in all three datasets. The crude cumulative 7-year re-revision rate for any reason following revision THA with Gentamicin ABLC use was 11.8%, with Gentamicin + Clindamycin ABLC use 13.1% and with Erythromycin + Colistin ABLC use 14.8% (ns). The crude cumulative 9-year re-revision rate for any reason following revision TKA with Gentamicin ABLC use was 17.7% and with Gentamicin + Clindamycin ABLC use 16.5% (ns). Conclusions. In conclusion, we could not show a difference in revision rate for hip fracture arthroplasty or re-revision rates for revision hip- or knee arthroplasty with the use of dual ABLC compared to single ABLC bone cement, with 7and 9 year follow up. The low percentage of dual ABLC in hip fracture arthroplasties in our registry do not enable us to make a reliable estimation of the added value in this patient category. The results of this study do not confirm the potential benefit of dual ABLC use in revision cases

The infected joint arthroplasty continues to be a very challenging problem. Its management remains expensive, and places an increasing burden on health care systems. It also leads to a long and difficult course for the patient, and frequently a suboptimal functional outcome. The choice of a particular treatment program will be influenced by a number of factors. These include the acuteness or chronicity of the infection; the infecting organism(s), its antibiotic sensitivity profile and its ability to manufacture glycocalyx; the health of the patient; the fixation of the prosthesis; the available bone stock; and the particular philosophy and training of the surgeon. For most patients, antibiotics alone are not an acceptable method of treatment, and surgery is necessary. The standard of care for established infection is two stage revision with antibiotic loaded cement during the interval period and parental antibiotic therapy for six weeks. Single stage revision may have economic and functional advantages, however. We have devised a protocol that dictates the type of revision to be undertaken based on host, organism and local factors. Our protocol has included single stage revision using antibiotic loaded cement in both THA and TKA. This was only undertaken when sensitive organisms were identified pre-operatively by aspiration and appropriate antibiotics were available to use in cement. Patients with immunocompromise, multiple infecting organisms or recurrent infection were excluded. Patients with extensive bone loss that required allograft reconstruction or where a cementless femoral component was necessary were also excluded. Our algorithm was validated first in the hip and extended to infected TKA in 2004. This protocol has now been applied in over 100 TKA revisions for infection between 2004 and 2009. Our single stage revision rate is now over 25%. We continue to see a lower reinfection rate in these carefully selected patients, with high rates of infection control and satisfaction and better functional and quality of life scores than our two stage revision cases. Whilst our indications are arbitrary and not based on specific biomarkers, we present excellent results for selective single stage exchange. A minimum three year follow-up suggests that these patients have shorter hospital stays, higher satisfaction rates and better knee scores. An ongoing evaluation is in place. One stage revision arthroplasty for infection offers potential clinical and economic advantages in selected patients

The infected joint arthroplasty continues to be a very challenging problem. Its management remains expensive, and places an increasing burden on health care systems. It also leads to a long and difficult course for the patient, and frequently a suboptimal functional outcome. The choice of a particular treatment program will be influenced by a number of factors. These include the acuteness or chronicity of the infection; the infecting organism(s), its antibiotic sensitivity profile and its ability to manufacture glycocalyx; the health of the patient; the fixation of the prosthesis; the available bone stock; and the particular philosophy and training of the surgeon. For most patients, antibiotics alone are not an acceptable method of treatment, and surgery is necessary. The standard of care for established infection is two-stage revision with antibiotic loaded cement during the interval period and parental antibiotic therapy for six weeks. Single stage revision may have economic and functional advantages however. We have devised a protocol that dictates the type of revision to be undertaken based on host, organism and local factors. Our protocol has included single stage revision using antibiotic loaded cement in both THA and TKA. This was only undertaken when sensitive organisms were identified pre-operatively by aspiration and appropriate antibiotics were available to use in cement. Patients with immunocompromise, multiple infecting organisms or recurrent infection were excluded. Patients with extensive bone loss that required allograft reconstruction or where a cementless femoral component was necessary were also excluded. Our algorithm was validated first in the hip and extended to infected TKA in 2004. This protocol has now been applied in over 100 TKA revisions for infection between 2004 and 2009. Our single stage revision rate is now over 25%. We continue to see a lower reinfection rate in these carefully selected patients, with high rates of infection control and satisfaction and better functional and quality of life scores than our two-stage revision cases. Whilst our indications are arbitrary and not based on specific biomarkers, we present excellent results for selective single stage exchange. A minimum three-year follow-up suggests that these patients have shorter hospital stays, higher satisfaction rates and better knee scores. An ongoing evaluation is in place. One-stage revision arthroplasty for infection offers potential clinical and economic advantages in selected patients

Infection of a total joint replacement (TJR) is considered a devastating complication, necessitating its complete removal and thorough debridement of the site. Usually at least two surgical interventions and antibiotic treatment within a period of several months are estimated being required for a favourable outcome. It is undoubted that one stage exchange, if successful, would provide the best benefit both for the patient and the society. Still the fear of re-infection dominates the surgeons’ decisions and directs them to multiple stage protocols. However, there is no scientifically based argument for that practice. Successful eradication of infection with two stage procedures is reported to average 80% to 98%, whereas there are no significant differences between revisions with or without antibiotic loaded cement, with short or long term antibiotic therapy, with or without the use of spacers and other differences. On the other hand a literature review of Jackson and Schmalzried (CORR 200) summarizing the results of 1,299 infected hip replacements treated with direct exchange (almost exclusively using antibiotic loaded cement), reports of 1,077 (83%) having been successful. For total knee replacement Jaemson et al. (Acta 2009) could show that the overall success rate in eradication of infection was 73–100% after one-stage revisions. It may be calculated, that adding a second one stage procedure for treating the failed cases the overall result with two operations may improve to > 95%, an outcome which is at least as good as the best results after two stage revisions, while requiring only one surgical intervention for the majority of cases. Spacers have been proven to be useful for improving final functional results compared to temporary resection; however, concerning infection control no benefit could be shown. Dead space management is performed comparably effective by a new prosthesis as with a spacer. In addition a definitive prosthesis is providing increased stability, which a spacer does not. As long as protection against colonization is granted by high local antibiotic concentrations a prostheses is likely to provide better functional results than a spacer. These results suggest, that the major factor for a successful outcome with traditional approaches may be found in the quality of the surgical debridement and dead space management. Failures in all protocols seem to be caused by small fragments of bacterial colonies remaining after debridement, whereas neither systemic antibiotics nor antibiotic loaded bone cement (PMMA) have been able to improve the situation significantly. One stage exchange provides marked reduction of patients discomfort and costs but is performed only rarely due to a multitude of risks and disadvantages, related to the mandatory use of antibiotic loaded cement for fixation. Cemented revisions generally show inferior long term results compared to uncemented techniques; the addition of antibiotics to cement reduces its biomechanical properties. The release of antibiotics from cement is too short-lived and concentrations are too low for reliable eradication of eventually remaining pathogens, especially when they are embedded within biofilms. PMMA has been shown to be the ideal substrate for bacterial attachment and replication of sessile bacterial phenotypes. Aging cement releases antibiotics in subinhibitory amounts, leading to antibiotic resistance of adherent bacteria even years after implantation. Whenever a new prosthesis is implanted into a previously infected site the surgeon must be aware of increased risk of failure, both in single or two stage revisions. Eventual removal therefore should be easy with low risk of additional damage to the bony substance in such a case. On the other hand it should also have potential of a good long term result in case of success. Cemented systems seem to be less likely for that purpose since efficient cementing techniques will result in tight bonding with the underlying bone. Eventual removal such will be time consuming and possibly associated with further damage to the osseous structures. Allograft bone may be impregnated with high loads of antibiotics using special incubation techniques. The storage capacities and pharmacological kinetics of the resulting antibiotic bone compound (ABC) are more advantageous than the ones of antibiotic loaded cement. ABC provides local concentrations exceeding those of cement by more than a 100 fold and efficient release is prolonged for several weeks. The same time they are likely to restore bone stock, which usually is compromised after removal of an infected endoprosthesis. ABC may be combined with uncemented implants which in case of a failure markedly facilitates their removal. There is reduced risk of creating resistances since the stored antibiotics are eluted completely and elution is terminated after several weeks. Based on this technology new protocols for one stage exchange of infected TJR have been established, both for hips and knees. Bone voids surrounding the implants are filled with antibiotic impregnated bone graft; uncemented implants are fixed in original bone. Recent studies indicate an overall success rate of more than 90% without any adverse side effects. Incorporation of allografts appears as after grafting with unimpregnated bone grafts. The favourable results have initiated extension of the technique to simultaneous reconstruction of large septic defects using impregnated bulk allografts. Antibiotic loaded bone graft seems to provide sufficient local antibiosis for protection against colonisation of uncemented implants, the eluted amounts of antibiotics are likely to eliminate biofilm remnants, dead space management is more complete and defects may be reconstructed efficiently. One stage revision such should be at least comparably save as multiple stage procedures, taking advantage of the obvious benefits for patients and economy

The infected joint arthroplasty continues to be a very challenging problem. Its management remains expensive, and places an increasing burden on health care systems. It also leads to a long and difficult course for the patient, and frequently a sub optimal functional outcome. The choice of a particular treatment program will be influenced by a number of factors. These include the acuteness or chronicity of the infection; the infecting organism(s), its antibiotic sensitivity profile and its ability to manufacture glycocalyx; the health of the patient; the fixation of the prosthesis; the available bone stock; and the particular philosophy and training of the surgeon. For most patients, antibiotics alone are not an acceptable method of treatment, and surgery is necessary. The standard of care for established infection is two stage revision with antibiotic loaded cement during the interval period and parental antibiotic therapy for six weeks. Single stage revision may have economic and functional advantages however. We have devised a protocol that dictates the type of revision to be undertaken based on host, organism and local factors. Our protocol has included single stage revision using antibiotic loaded cement in both THA and TKA. This was only undertaken when sensitive organisms were identified preoperatively by aspiration and appropriate antibiotics were available to use in cement. Patients with immunocompromise, multiple infecting organisms or recurrent infection were excluded. Patients with extensive bone loss that required allograft reconstruction or where a cementless femoral component was necessary were also excluded. Our algorithm was validated first in the knee and extended to infected TKA in 2004. This protocol has now been applied in over 100 TKA revisions for infection between 2004 and 2009. Our single stage revision rate is now over 25%. We continue to see a lower reinfection rate in these carefully selected patients, with high rates of infection control and satisfaction and better functional and quality of life scores than our two stage revision cases. Whilst our indications are arbitrary and not based on specific biomarkers, we present excellent results for selective single stage exchange. A minimum three year follow-up suggests that these patients have shorter hospital stays, higher satisfaction rates and better knee scores. An ongoing evaluation is in place. One stage revision arthroplasty for infection offers potential clinical and economic advantages in selected patients

Aims: Purpose of this study was to evaluate the results of a staged revision technique in the treatment of deep infection after limb salvage surgery for bone tumors and to identify factors possibly affecting the outcome. Methods: A retrospective study of 19 consecutive patients with an infected bone tumor reconstruction treated at our Institution in the period 1986–1997 was undertaken. All the patients underwent staged revision (two stages in 13 cases, three stages in 5, four stages in 1) using one or more antibiotic loaded cement spacers after debridement and partial (10 cases) or complete (9 cases) removal of the original implant. Postoperatively, all the patients received oral or parenteral antibiotics for a minimum of 4 weeks. Delayed reimplantation was performed in 15 cases, average time to reimplantation being 7 months (4–14). A minimum follow up of 3 years was available in all patients. Cultures identiþed S. Epider-midis in 12 cases (63%), S. Aureus in 4 (21%), mixed organisms in 2 (11%), and were negative in 1 case (5%) despite clinical evidence of infection. Results: At a minimum follow-up of 3 years, 13 patients were continuously infection-free (68%) while 6 relapsed (32%). Two of the 6 relapses were cleared by amputation while 4 remained infected. Average functional result of infection-free patients according to the International Society Of Limb Salvage (ISOLS) was 71% (21.2 points), ranging from 60% to 80% (18 to 24 points). Conclusions: Staged revision with antibiotic loaded cement spacer for infected bone tumor reconstruction is a demanding and expensive technique requiring prolonged inability. Overall success rate in this series approaches 70%. Complete removal of the infected implant, microbiology, appropriate antibiotic selection, and negative cultures before reimplantation are crucial

The management of infected total hip replacements remains controversial. The standard of care is two stage revision with antibiotic load ed cement during the interval period and parental antibiotic therapy for six weeks. Single stage revision may have economic and functional advantages however. Fifty consecutive patients with infected total hip replacements were treated according to a Standard Protocol. Patients were selected for single or two stage revision based on their general characteristics, the infecting organisms and type of reconstruction to be used. If a single sensitive organism was identified and antibiotics were available to use antibiotic loaded cement on the femoral side then a single stage revision was undertaken. Eleven patients underwent a single stage revision and 39 two stage revision. All 11 patients who underwent single stage revision had femoral components inserted using antibiotic loaded cement. Six had uncemented acetabular components. All the patients were reviewed at a minimum of 2 years post surgery. There was evidence of re-infection in two cases who were treated w ith two stage exchange and in none of the one stage revisions. The average Harris hip score in the patients treated with one stage exchange improved from 42 to 85. In the patients treated with two stages the scores improved from 36 to 73. Patients with one stage exchange were significantly more satisfied than those undergoing two stage exchange. Single stage exchange arthroplasty can be performed in selected patients with excellent success rates. We have not seen any detrimental effects of using uncemented acetabular components in these cases although we continue to use cement on the femoral side to provide a high local antibiotic load. At a minimum of 2 years of follow up of single stage revision appears to offer some advantages in specific patients over two stage exchange

Aim: To determine the cost of medical treatment of infection following total joint replacement (TJR) of the hip or knee. With this information, and obtaining the current costs of antibiotics, antibiotic loaded cement and laminar flow theatres, we aimed to calculate the relative cost- benefit of these prophylactic strategies to prevent infection. Method: Fifty two patients who were admitted to The Canberra Hospital (TCH) for treatment of infection at following total joint arthroplasty between January 1996 and January 2001. A detailed cost analysis of treatment costs following infection was performed. All ward, theatre, prosthesis, investigation, pharmaceutical, allied health and medical costs were collated to produce a total cost of treatment. Current costs of prophylactic antibiotics, antibiotic cement and laminar flow theatres were obtained from suppliers. Costs were calculated for different combinations of prophylactic measures using the rates of deep periprosthetic infection reported through the Swedish Arthroplasty Registry. Results: There were 41 deep infections and 13 superficial. The average cost for the 54 patients for the in hospital treatment of infection was $41,215. The cost of treating a superficial infection with antibiotics alone averaged $17,663. The average cost of a two stage revision procedure for deep periprosthetic infection was $79,623. Assuming a hospital volume of 150 cases per year, the use of prophylactic intravenous antibiotics, the use of laminar flow and the combined use of antibiotics and laminar flow were significantly cost effective. The addition of antibiotic loaded cement was marginally cost ineffective in combination with either or both of intravenous antibiotics or laminar flow. Conclusion: The in hospital costs for the treatment of infection after TJR in the Australian setting have been addressed for the first time. Past studies have underestimated the cost of treatment. With this information, we have shown that the combinations of laminar flow and intravenous antibiotic for prophylaxis against infection in TJR are justified on a purely financial cost benefit basis

Introduction: Chronic hip arthroplasty infection is a difficult situation to solve. The use of uncemented stem is questionable, as no antibiotic loaded cement is used to fix the implant. Bone deficiencies are often enlarged by the chronic infection process and the multiple previous surgeries. We report our experience in two stage revisions with massive allograft and uncemented distal locked stem. Material and method: We have retrospectively reviewed 15 patients operated on from chronic hip arthroplasty infection and secondary large femoral defects. Two stages revision with a temporarily antibiotic loaded cement spacer and 6-weeks second look reconstruction were performed with massive proximal femoral allograft and a long distally locked stem. The uncemented stem was cemented into the allograft and remained uncemented in the recipient distal femur. Outcome was assessed regarding infection control, allograft complication and function according to the Merle d’Aubigné score. Results: Patients mean age was 62 years (SD 11). Patients were already operated from the same hip 5.9 +/− 2.3 times before the actual procedure. Isolated microorganisms were MRSE (7), staph Aureus (4), MRSA (1), VRE (1), enterococcus (2). Muscle flaps were performed in 2 cases and discuss for 2 more. Allograft length was 22 +/− 9 cm. Antibiotic treatment was maintained for 4.6 +/− 2.5 months (median 3 months). Mean follow-up was 29 months (SD 26; median 23). Clinical outcome based on Merle d’Aubigné score is 5.3 +/− 3 before treatment and 13.8 +/− 2.5 at the last visit. Complications were registered in 4 cases. Infection recurrence was observed in 3 cases (2,7,20 months) but the function was preserved in all cases. One of them needed a two stage procedure with a new allograft after 19 months due to acute staph Aureus infection. One allograft was broken after 80 months and need one stage revision. Discussion: While the treatment of these cases was particularly demanding as bone deficiencies and microorganisms antibiotic resistance were high, functional result obtained was good. When infection recurrence was observed, function remains preserved. The use of uncemented distal locked stem with a cemented massive allograft did not lead to mechanical or hardware problem and allow us to restore the bone stock and the gluteus tendons insertion. The use of a modular stem was very helpful in solving these complex situations. Massive allografts can be used in case of infection as antibiotic delivery system

Despite the increasing availability of bone grafting materials, the regeneration of large bone defects remains a challenge. Especially infection prevention while fostering regeneration is a crucial issue. Therefore, loading of grafting material with antibiotics for direct delivery to the site of need is desired. This study evaluates the concept of local delivery using in vitro and in vivo investigations. We aim at verifying safety and reliability of a perioperative enrichment procedure of demineralized bone matrix (DBM) with gentamicin. DBM (DBMputty, DIZG, Germany) was mixed with antibiotic using a syringe with an integrated mixing propeller (Medmix Systems, Switzerland). Gentamicin, as powder or solution, was mixed with DBM at different concentrations (25 −100 mg/g DBM), release and cytotoxicity was analyzed. For in vivo analysis, sterile drill hole defects (diameter: 6 mm, depth: 15 mm) were created in diaphyseal and metaphyseal bones of sheep (Pobloth et al. 2016). Defects (6 – 8 per group and time point) were filled with DBM or DBM enriched with gentamicin (50 mg/g DBM) or left untreated. After three and nine weeks, defect regeneration was analyzed by µCT and histology. The release experiments revealed a burst release of gentamicin from DBM independent of the used amount, the sampling strategy, or the formulation (powder or solution). Gentamicin was almost completely released after three days in all set-ups. Eluates showed an antimicrobial activity against S. aureus over at least three days. Eluates had no negative effect on viability and alkaline phosphatase activity of osteoblast-like cells (partially published Bormann et al. 2014). µCT and histology of the drill hole defects revealed a reduced bone formation with gentamicin loaded DBM. After nine weeks significantly less mineralized tissue was detectable in metaphyseal defects of the gentamicin group. Histological evaluation revealed new bone formation starting at the edges of the drill holes and growing into the center over time. The amount of DBM decreased over time due to the active removal by osteoclasts while osteoblasts formed new bone. Using this mixing procedure, loading of DBM was fast, reliable and possible during surgical setting. In vitro experiments revealed a burst and almost complete release after three days, antimicrobial activity and good biocompatibility of the eluates. Gentamicin/DBM concentration was in the range of clinically used antibiotic-loaded-cement for prophylaxis and treatment in joint replacement (Jiranek et al. 2006). The delayed healing seen in vivo was unexpected due to the good biocompatibility found in vitro. A reduced healing was also seen in spinal fusion where DBM was mixed with vancomycin (Shields et al. 2017), whereas DBM with gentamicin or DBM/bioactive glass with tobramycin had no negative effect on osteoinductivity or femur defect healing, respectively (Lewis et al. 2010, Shields et al. 2016). In conclusion, loading of DBM with gentamicin showed a proper antibiotic delivery over several days, covering the critical phase shortly after surgery. Due to the faster and complete release of the antibiotic compared to antibiotic loaded cement, the amount of antibiotic should be much lower in the DBM compared to cement

Total joint replacement (TJR), such as hip and knee replacement, is commonly used for the treatment of end stage arthritis. The use of Poly (methylmethacrylate) bone cement is a gold standard in such replacement, where it fixes the implant in place and transfer stresses between bone and implant, and frequently used for local delivery of drugs such as antibiotics. The use of antibiotic loaded bone cement is considered a well-established standard in the treatment and prophylaxis of Prosthetic joint infections (PJI). PJIs is a serious problem that decreases success rate of surgery and can be life threatening to patients, where the incidence can reach up 2% in total and hip replacements and up to 40% for revision surgery. Currently used antibiotic loaded bone cements have many limitations, including burst release of < 10% of antibiotic added. This burst release falls rapidly below inhibitory level within few days, which leads to selection of resistant antimicrobial strains and does not provide prophylaxis from early and delayed stage infection. This study aims to provide a controlled release for gentamicin when loaded on Silica nanoparticles (NP) using layer-by-layer technique (LbL) to provide prophylaxis and treatment from postsurgical infections. The gentamicin loaded NPs were incorporated into PMMA bone cement and the new nanocomposite is characterized for gentamicin release, antimicrobial and mechanical properties. Our results showed that the nanocomposite gentamicin release continued for 30 days at concentration 3 times higher than the commercial formulation containing the same amount of gentamicin, where burst release for few days were observed. Moreover, the nanocomposite showed superior antimicrobial inhibition for bacterial growth and good cytocompatibility without adversely affecting the cement compressive strength, bending and fracture toughness properties

Aim. To assess the effectiveness of role of frozen section in revision arthroplasty. Method. 21 patients with infected hip arthroplasties were operated in the form of one or two-staged revision hip arthroplasties. A frozen section was obtained intra-operatively and >5 PMN's/ HPF was considered as a positive indicator of infection. Fig 1 llustrating frozen section image. If the frozen section was reported negative (≤5 PMN's/HPF), the revision prosthesis was implanted after a thorough debridement and a wash. If the frozen section was reported as positive, after the debridement a non-articulating antibiotic loaded cement spacer was implanted for 8 weeks, supplemented with 3 weeks of intravenous antibiotics and 3 weeks of oral antibiotics. This was followed by an antibiotic free interval of 2 weeks. The patient was taken up for a revision surgery once the frozen section study was negative (≤5 PMN's/HPF). The patients were followed up for minimum of 1 year to a maximum of 2 years after the revision for any evidence of infection (assessed clinically and serologically, radiologically). Results. 15 patients had a positive frozen section (>5PMN's/HPF) in the first stage and were treated with prosthesis removal and cement spacer insertion for 8 weeks. In the 2nd stage, out of 15 patients, 14 underwent revision arthroplasty, while 1 patient underwent reapplication of the cement spacer. As per the follow up of ESR & CRP values, clinically and radiologically no patients had any evidence of infection. The average follow up was 17.04 months (range 12–24 months). 1 patient had persistently raised ESR (34mm/hr) which may be attributable to other causes Frozen section analysis of PMN's per high power field had 100% specificity in our patients in detecting periprosthetic joint infection. Conclusions. Intraoperative frozen section study is a reliable indicator in predicting a diagnosis of PJI with good accuracy in ruling out this diagnosis. Frozen section study should thus be considered a relevant part of the challenging diagnostic work-up for patients undergoing revision hip arthroplasty

Orthopedic device-related bone infection is one of the most distressing complications of the surgical fixation of fractures. Despite best practice in medical and surgical interventions, the rate of infection remains stubbornly persistent, and current estimates indicate that treatment failure rates are also significant. As we approach the limit of the effectiveness of current anti-infective preventative and therapeutic strategies, novel approaches to infection management assume great importance. This presentation will describe our efforts to develop and test various hydrogels to serve as customized antibiotic delivery vehicles for infection prevention and treatment. Hydrogels offer solutions for many of the challenges faced by complex trauma wounds as they are not restricted spatially within a poorly defined surgical field, they often degrade rapidly with no compatibility issues, and releases 100% of the loaded antibiotic. The preliminary data set proving efficacy in preventing and treating infection in both rabbit and sheep studies will be described, including local antibiotic concentrations in the intramedullary canal over time, compared to that of the more conventional antibiotic loaded bone cement. These two technologies show potential for the prevention and treatment of infection in trauma patients, with a clear focus on optimized antibiotic delivery tailored for complex wounds