Aims. Uncemented implants are now commonly used at reimplantation of a two-stage revision total hip arthoplasty (THA) following periprosthetic joint infection (PJI). However, there is a paucity of data on the performance of the most commonly used uncemented femoral implants – modular fluted tapered (MFT) femoral components – in this setting. This study evaluated implant survival, radiological results, and clinical outcomes in a large cohort of reimplantation THAs using MFT components. Methods. We identified 236 reimplantation THAs from a single tertiary care academic institution from September 2000 to September 2020. Two designs of MFT femoral components were used as part of an established two-stage exchange protocol for the treatment of PJI. Mean age at reimplantation was 65 years (SD 11), mean BMI was 32 kg/m. 2. (SD 7), and 46% (n = 109) were female. Mean follow-up was seven years (SD 4). A competing risk model accounting for death was used. Results. The 15-year cumulative incidence of any revision was 24%. There were 48 revisions, with the most common reasons being dislocation (n = 25) and infection (n = 16). The 15-year cumulative incidence of any reoperation was 28%. Only 13 revisions involved the fluted tapered component (FTC), for a 15-year cumulative incidence of any FTC revision of 8%. Only two FTCs were revised for aseptic loosening, resulting in a 15-year cumulative incidence of FTC revision for aseptic loosening of 1%. Stem subsidence ≥ 5 mm occurred in 2% of unrevised cases. All stems were radiologically stable at most recent follow-up. Mean Harris Hip Score was 69 (SD 20) at most recent follow-up. Conclusion. This series demonstrated that MFT components were durable and reliable in the setting of two-stage reimplantation THA for infection. While the incidence of aseptic loosening was very low, the incidence of any revision was 24% at 15 years, primarily due to dislocation and recurrent PJI. Cite this article: Bone Joint J 2024;106-B(5 Supple B):125–132

Aim. D-dimer is a widely available serum test that detects fibrinolytic activities that occur during infection. Prior studies have explored its utility for diagnosis of chronic periprosthetic joint infections (PJI), but not explored its prognostic value for prediction of subsequent treatment failure. The purpose of this study was to: (1) assess the ability of serum D-dimer and other standard-of-care serum biomarkers to predict failure following reimplantation, and (2) establish a new cutoff value for serum D-dimer for prognostic use prior to reimplantation. Method. This prospective study enrolled 92 patients undergoing reimplantation between April 2015 and March 2019 who had previously undergone total hip/knee resection arthroplasty with placement of an antibiotic spacer for treatment of chronic PJI. Serum D-dimer level, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels were measured preoperatively for all patients. Failure following implantation was defined per the Delphi consensus criteria. Optimal cutoffs for D-dimer, ESR, and CRP were calculated based on ROC curves and compared in their association with failure following reimplantation criteria at minimum 1-year follow-up. Results. 15/92(16.3%) patients failed reimplantation surgery at mean follow up of 2.9 years (range 1.0–4.8). Optimal thresholds for D-Dimer, ESR and CRP were determined to be 1300ng/mL, 30mm/hr, and 1mg/L, respectively. The failure rate in patient with positive D-dimer was significantly higher at 32.0% (8/25) compared to those with negative D-dimer 10.6% (7/66); p=0.024. In comparison, 17.8% (8/45) of patients with ESR above threshold failed, compared to 13.89% (5/41) below (p=0.555) and 16.0% (4/25) of patients with CRP above threshold failed, compared to 16.1% (10/62) below (p=1.000). Conclusions. Patients with elevated D-Dimer appear to be at higher risk of failure after reimplantation surgery. This serum marker may be used to generate an additional data point in patients undergoing reimplantation surgery, especially in circumstances when optimal timing of reimplantation cannot be determined based on clinical circumstances

Aims. It can be extremely challenging to determine whether to perform reimplantation in patients who have contradictory serum inflammatory markers and frozen section results. We investigated whether patients with a positive frozen section at reimplantation were at a higher risk of reinfection despite normal ESR and CRP. Methods. We retrospectively reviewed 163 consecutive patients with periprosthetic joint infections (PJIs) who had normal ESR and CRP results pre-reimplantation in our hospital from 2014 to 2018. Of these patients, 26 had positive frozen sections at reimplantation. The minimum follow-up time was two years unless reinfection occurred within this period. Univariable and multivariable logistic regression analyses were performed to identify the association between positive frozen sections and treatment failure. Results. Treatment failure occurred in eight (30.77%) of the 26 PJI patients with positive frozen sections at reimplantation, compared with 13 (9.49%) of 137 patients with negative results. In the multivariate analysis, positive frozen section increased the risk of failure (odds ratio 4.70; 95% confidence interval (CI) 1.64 to 13.45). The mean number of months to reinfection was lower in the positive frozen section group than in the control group (p = 0.041). While there were nine (34.62%) patients with positive frozen section and 25 (18.25%) patients with negative frozen section who had prolonged antibiotic use (p = 0.042), the mean duration of antibiotic use was comparable in two groups. Synovial white blood cell count (p = 0.137) and polymorphonuclear leucocyte percentage (p = 0.454) were not associated with treatment failure in logistic regression model. Conclusion. Positive frozen section at reimplantation was independently associated with subsequent failure and earlier reinfection, despite normal ESR and CRP levels pre-reimplantation. Surgeons should be aware of the risk of treatment failure in patients with positive frozen sections and carefully consider benefits of reimplantation. Cite this article: Bone Joint J 2021;103-B(5):916–922

There is a paucity of long-term data on modular fluted tapered (MFT) stems for two-stage reimplantation following periprosthetic joint infection (PJI). The purpose of this study was to evaluate implant survivorship, radiographic results, and clinical outcomes in a large cohort of reimplantation THAs using MFT stems. We identified 236 reimplantation THAs from a single tertiary care academic institution from 2000 to 2020. Two designs of MFT stems were used as part of an established two-stage exchange protocol for the treatment of PJI. Mean age at reimplantation was 65 years, mean BMI was 32 kg/m. 2. , and 46% were female. Median stem diameter was 19 mm, and median stem length was 195 mm. Mean follow-up was 7 years. A competing risk model accounting for death was utilized. The 15-year cumulative incidence of any revision was 24%. There were 48 revisions, with the most common reasons being dislocation (n=25) and PJI (n=16). The 15-year cumulative incidence of any reoperation was 28%. Only 13 revisions involved the fluted tapered portion of the component (FTC), for a 15-year cumulative incidence of any FTC revision of 8%. Only 2 FTCs were revised for aseptic loosening, resulting in a 15-year cumulative incidence of FTC revision for aseptic loosening of 1%. Stem subsidence >5 mm occurred in 2% of unrevised cases, and all stems were radiographically stable at most recent follow-up. Mean HHS was 77 at most recent follow-up. This series demonstrated that MFT stems were durable and reliable even in the setting of two-stage reimplantation for infection. While the incidence of aseptic loosening was very low, the incidence of any revision was 24% at 15 years, primarily caused by dislocation and recurrent PJI. Level of Evidence: IV

Aims. We aimed to report the mid- to long-term rates of septic and aseptic failure after two-stage revision surgery for periprosthetic joint infection (PJI) following total hip arthroplasty (THA). Methods. We retrospectively reviewed 96 cases which met the Musculoskeletal Infection Society criteria for PJI. The mean follow-up was 90 months (SD 32). Septic failure was assessed using a Delphi-based consensus definition. Any further surgery undertaken for aseptic mechanical causes was considered as aseptic failure. The cumulative incidence with competing risk analysis was used to predict the risk of septic failure. A regression model was used to evaluate factors associated with septic failure. The cumulative incidence of aseptic failure was also analyzed. Results. There were 23 septic failures at final follow-up, with a cumulative incidence of 14% (95% confidence interval (CI) 8% to 22%) at one year, 18% (95% CI 11% to 27%) at two years, 22% (95% CI 14% to 31%) at five years, and 23% (95% CI 15% to 33%) at ten years. Having at least one positive culture (hazard ratio (HR) 2.38 (interquartile range (IQR) 1.19 to 4.74); p = 0.013), or a positive intraoperative frozen section (HR 2.55 (IQR 1.06 to 6.15); p = 0.037) was significantly associated with septic failure after reimplantation. With dislocation being the most common cause of aseptic revision (5.2%), the cumulative incidence of aseptic failure was 1% (95% CI 0% to 5%) at one year, 6% (95% CI 1% to 8%) at five years, and 8% (95%CI 3% to 17%) at ten years. Conclusion. If there is no recurrent infection in the five years following reimplantation, the chances of further infection thereafter are remote. While the results of a frozen section may be a reliable guide to the timing of reimplantation, intraoperative culture has, currently, only prognostic value. Surgeons should be aware that instability remains a potential indication for further revision surgery. Cite this article: Bone Joint J 2021;103-B(1):79–86

Aim. The diagnosis of periprosthetic joint infection (PJI) remains a clinical dilemma, since presentations of PJI usually greatly overlap with aseptic failure (AF). The aim of this study is to evaluate the values of plasma fibrinogen, individually or in combination with CRP, ESR and WBC, for distinguishing PJI from AF. Method. We retrospectively enrolled 357 cases who underwent revision hip or knee arthroplasties in the Third Affiliated Hospital of Southern Medical University, Sun Yat-sen Memorial Hospital and the First Affiliated Hospital of Sun Yat-sen University from January 2013 to December 2021, including 197 AF, 116 PJI and 44 reimplantation. The diagnostic capacity of preoperative fibrinogen, CRP, ESR and WBC as well as their combinations for differentiating PJI from AF were assessed by ROC curves. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were calculated according to the optimal cutoff value based on the Youden index. All biomarkers were further investigated for their potential ability to predict optimal timing of reimplantation as well as their diagnostic capacity in the subgroups of the knee and hip PJI. Furthermore, the correlations among fibrinogen, CRP and ESR in the patients with PJI and AF were analyzed to further evaluate the potential capacity of fibrinogen in the diagnosis of PJI. Results. The levels of fibrinogen, CRP, ESR and WBC were significantly higher in PJI group than in AF group. ROC analyses showed that the AUCs of fibrinogen, CRP, ESR and WBC were 0.879, 0.903, 0.879 and 0.685, respectively. The optimal threshold of fibrinogen is 4.04 g/L (74.1% sensitivity, 85.6% specificity, 76.1% PPV, 85.0% NPV and 81.8% accuracy). Combining fibrinogen with CRP and/or ESR (AUC: 0.903∼0.914) yielded almost equivalent diagnostic efficiency compared with the combination of CRP and ESR (AUC: 0.910). Besides, fibrinogen yielded AUCs of 0.869 (cutoff: 3.44 g/L) and 0.887 (cutoff: 4.12 g/L) in the hip and knee subgroups, with higher specificity and PPV of 93.1% and 96.1% in the knee PJI. Intriguingly, as for the cases with CRP < 10mg/L and ESR ≧ 30 mm/h, the specificity and NPV of fibrinogen for diagnosing PJI were 92.2% and 83.9%. Conclusions. Plasma fibrinogen is considered as a potential first-line screening marker for PJI detection and timing of reimplantation. As for the patients with an increased ESR but normal CRP, a low fibrinogen level (below 4.04 g/L) is more likely to rule out PJI

Introduction. Two-stage reimplantation for prosthetic joint infection (PJI) of the hip is the standard of care with a 5–10% recurrence at a minimum two-year follow-up. Compiling outcomes data for this standard of care is necessary in order to characterize long-term reinfection risk and the culpable microbiology. The purpose of this study was to determine the long-term success of two-stage reimplantation and identify the factors that affected the success. Methods. We performed a systematic review of randomized control trials, cohort studies, and case series through May 2019, searching Embase, Medline via PubMed, and Cochrane Library for the concept of two-stage reimplantation for the treatment of hip and knee PJIs, yielding 464 unique citations for abstract review, of which 135 were reviewed in full. Our parameters of interest included: reinfection and mortality events following successful reimplantation, the timing of these events, and the microbiology of index and recurrent infections. Results. Meeting our criteria were 59 studies with 4,494 patients (1,842 hips) who had completed reimplantation. Among successfully reimplanted hips, 4.76% (95% CI, 2.00–8.41) were reinfected by 24 months, 6.84% (4.92–9.02) were reinfected by final follow-up, 1.6% (0.32–3.52) were reinfected with an identical organism(s) with identical resistance, and 2.55% (0.77–5.03) were reinfected with a novel organism(s) or novel resistance. In 24 studies with reinfected patients and sufficient data, 8 studies reported an average interval from reimplantation to reinfection greater than 24 months, and 14 reported at least 1 patient with a reinfection event greater than 48 months following reimplantation. Conclusion. The results from this review determined that the host of an index PJI faces ongoing risk of recurrent infection years into the post-operative period despite initial eradication and that novel microbiology is the cause of a significant proportion of failures. For any tables or figures, please contact the authors directly

Aim. A two-stage exchange of an infected prosthetic joint (PJI) is considered the most effective surgical treatment of chronic PJIs, particularly in North America. However, reinfection rates are unacceptably high (10–20%). This could be the consequence of a persistent infection or a new infection introduced during the first or second stage of the exchange arthroplasty. We aimed to determine: i) the prevalence of positive cultures at reimplantation, ii) whether there is an association between positive cultures at reimplantation and reinfection during follow-up, and iii) if there is a microbiological correlation between primary infections, reimplantations and reinfections. Method. We retrospectively evaluated all two-stage exchange procedures performed at two academic centers between 2000 and 2015. Primary culture-negative PJIs and cases in whom no intraoperative cultures were obtained during reimplantation were excluded from the analysis. One or more positive intraoperative cultures during reimplantation were considered positive for infection. Reinfection was defined as the need for additional surgical intervention after reimplantation or the need for antibiotic suppressive therapy due to persistent clinical signs of infection. Results. A total of 424 cases were included in the final analysis with a mean follow-up of 48 months (SD 37). Eighty-eight cases (20.8%) had positive cultures during reimplantation (second stage) of which 68.1% (n=60) grew a different microorganism than during the first stage of the procedure. The percentage of positive cultures during reimplantation was higher for hips than for knees (26.5% vs 17.1%, p 0.02). For the total group, the reinfection rate during follow-up was 18.4% (78/424), which was 29.5% for the positive-culture group versus 15.5% for the culture-negative group at reimplantation (p=0.002). A positive culture during reimplantation was an independent risk factor for reinfection during follow-up in the multivariate analysis (OR 2.2 (95% CI 1.2 – 3.8), p 0.007). Reinfection was caused by a different microorganism than the primary infection (first stage) in 64.1% of cases (50/78). Conclusions. There is a very high rate of positive cultures at reimplantation, which are mostly attributed to a different microorganism than the primary infection and is associated with a worse outcome. These results stress the importance of developing treatment strategies for this particular population

Introduction. Debridement, antibiotics, and implant retention (DAIR) for acute prosthetic hip infection is a popular low morbidity option despite less than optimal success rates. We theorized that the delay between DAIR and explantation in failed cases may complicate eradication due to biofilm maturation and entrenchment of bacteria in periprosthetic bone. We ask, what are the results of two-stage reimplantation after a failed DAIR versus an initial two-stage procedure?. Methods. 114 patients were treated with 2-stage exchange for periprosthetic hip infection. 65 were treated initially with a 2-stage exchange, while 49 underwent an antecedent DAIR prior to a 2-stage exchange. Patients were classified according to MSIS host criteria. Failure was defined as return to the OR for infection, a draining sinus, or systemic infection. Results. Treatment failure occurred in 42.9% (21 of 49) of patients treated with an antecedent DAIR. In contrast, treatment failure occurred in only 12.3% (8 of 65) of initial 2-stage procedures (p< 0.001). Relative Risk of return to the OR after a 2-stage reimplantation with an antecedent DAIR compared to initial resection was 4.52 (95% CI 1.71, 11.9). MSIS host grading was similar between groups and did not influence the rate of failure. The DAIR cohort had increased hospitalization length and greater number of operative procedures (p< 0.001). Conclusion. We have shown that if irrigation and debridement fails to treat acute prosthetic hip infection, subsequent attempts at two-stage reimplantation may be compromised. Additionally, in the antecedent DAIR group, the average number of infection-related procedures (5) was nearly twice that of those initially resected (2.7). This by nature implies a significantly greater burden to the patient and cost to the healthcare system

Reimplantation is a well-established procedure in reconstructive surgery. This is especially so after amputation of the upper limb since prostheses provide limited function. In unilateral amputation of the lower leg orthotopic reimplantation is the treatment of choice. With bilateral amputation, in which orthotopic reimplantation is not possible because of the complexity of the trauma, heterotopic reimplantation is an option. We report five patients who received orthotopic and two who received heterotopic reimplantations of the lower leg. We assessed the functional outcome with reference to cutaneous sensation, mobility, pain, and the cosmetic result. The functional outcome was good, as was the patients’ satisfaction. Their mobility, stability, and psychological state were satisfactory. Patients with heterotopic reimplantations preferred the reimplanted leg to a prosthesis. Although reimplantation of the lower leg requires prolonged hospitalisation, delayed mobilisation and secondary operations, we conclude that there is an indication for this operation in order to improve the patient’s quality of life

It is strongly recommended that tissue and synovial fluid culture samples be obtained during reimplantation performed as part of a two-stage exchange arthroplasty. The incidence of positive cultures during reimplantation and the influence of positive cultures on subsequent outcome are unknown. This aim of this study was to determine the incidence of positive cultures during reimplantation and to investigate the association between positive cultures at reimplantation and the subsequent outcome. A retrospective review was conducted on 267 patients that met the Musculoskeletal Infection Society (MSIS) criteria for PJI that completed both stages of two-stage exchange arthroplasty (Table 1). Intraoperative culture results from tissue and/or synovial fluid were obtained. Cultures were positive in 33 cases (12.4%) undergoing reimplantation surgery (Figure 1). Treatment failure was assessed based on the Delphi consensus definition. Logistic regression analysis was performed to assess the predictors of positive culture and risk factors for failure of two-stage exchange arthroplasty. Treatment failure was 45.5% for those with a positive intraoperative culture and 20.9% in those with negative cultures at the time of reimplantation. When controlling for organism virulence, comorbidities, and other confounding factors, treatment failure was higher (odds ratio [OR]: 3.3; 95% confidence interval [CI]: 1.3–4.5) and occurred at an earlier time point (hazard ratio: 2.5; 95% CI: 1.3–4.5) in patients with a positive reimplantation culture. The treatment failure rate was not different between cases with two or more positive cultures (36.4%) and one positive culture (42.8%). Positive intraoperative cultures during reimplantation, regardless of the number of positive samples were independently associated with two times the risk of subsequent infection and earlier treatment failure. Surgeons should be aware that a positive culture at the time of reimplantation independently increases the risk of subsequent failure and needs to be taken seriously. Given the significance of these findings, future studies are needed to evaluate the optimal management of positive cultures during reimplantation surgery

Two-stage reimplantation is currently the most widely accepted method of treatment for a periprosthetic hip infection. However, it remains controversial whether the treatment protocol may be equally effective in the eradication of resistant microorganisms. We compared the results of two-stage reimplantation performed for periprosthetic hip infection caused by resistant microorganisms with those performed for periprosthetic hip infection caused by non-resistant microorganisms. We reviewed a consecutive series of 32 patients (32 hips) who had a culture-proven deep infection at the site of hip arthroplasty and were treated by a two-stage reimplantation protocol. Based on the antibiotic sensitivities of the infecting microorganisms, the patients were divided into two groups. Resistant microorganism group consisted of 20 patients who had an infection with antibiotic-resistant bacterial strains (methicillin-resistant Staphylococcus aureus in 11 and methicillin-resistant Staphylococcus epidermidis in 9). Non-resistant microorganism group consisted of 12 patients who had an infection with antibiotic-sensitive bacterial strains. The treatment was considered a failure if the patient had a persistent infection after the first-stage procedure or a recurrence of infection after reimplantation. The mean duration of follow-up after the index procedure was 45 months (24 to 123). Among the entire series of the 32 patients, the second-stage reimplantation was able to be performed in 29 patients (91%) and the remaining three went on to a permanent resection of the hip because of persistent infections. After the two-stage reimplantation, four patients had a recurrence of infection (relapse of infection with the same microorganism in three and reinfection with different resistant microorganism in one). Thus, overall treatment failure rate was 22% and all these failures occurred among patients with resistant microorganisms. Treatment failure rate of 35% in resistant microorganism group was significantly higher than that of 0% in the non-resistant microorganism group (p = 0.029). None of the variables evaluated in this study was found to be significantly associated with the treatment failure in the resistant microorganism group. Current two-stage reimplantation protocol showed a high rate of treatment failure in our patients who had periprosthetic hip infection caused by methicillin-resistant bacterial strains. Further study is needed to develop optimal treatment strategy for this difficult-to-treat condition

Introduction. The goal of treating artificial joint infection is to relieve the infection quickly and re-establish joint function, but many patients have underlying diseases, and treatment is often made problematic by the diversity of the causative bacteria. In this study we assessed the factor that enabled revision arthroplasty in patients with infection after artificial hip arthroplasty, including bipolar hip arthroplasty, in our hospital. Subjectives and Methods. The subjects were the 16 patients (16 hips) with infection after hip arthroplasty who were treated in our hospital during the past 10 years. There were 7 males and 9 females, and their mean age was 69.8 years. Primary total hip arthroplasty had been performed in 6 hips, revision hip arthroplasty in 8 hips, and bipolar hip arthroplasty in 2 hips. Infected implants were removed as soon as possible and delayed reimplantations with an interval antibiotic spacer were attempted in all patients. 9 hips were successful in reimplantation (reimplantation group) and 7 hips were impossible (No reimplantation group). In this study we investigated age, complications, body mass index (BMI), body temperature, pain, rate of resistant bacteria, number of hip surgery prior to infection and clinical manifestations compared to two groups. Results. Age, rate of resistant bacteria, body temperature and number of surgery were not significantly different compared to two groups. In no reimplantation group BMI was significantly low. Also, local heat, redness and fistula as clinical manifestations had been observed in most no reimplantation hips. Conversely there were no associations with the presence or absence of swelling, tenderness and pain in initial consultation. Discussion. Garvin et al. have reported a two-stage reimplantation success rate for infected artificial joints of 91%. However, our results comparatively showed lower successful rate. It is suggested that lower BMI, presence of local heat, redness and fistulation were risk factors for reimplantation. Especially, these clinical manifestations means that the infection widely invade to subcutaneous tissue. Therefore, we should performed debridement and antibiotic treatment more carefully

One-stage reimplantation for the salvage of infected total knee arthroplasty in 18 patients was reviewed at an average follow-up of five years. There had been one recurrence and one new infection, both in rheumatoid patients with another focus of infection. In four other patients the clinical result was impaired by pain after walking (2) and limited flexion (2). Our results suggest that one-stage reimplantation is a reasonably reliable procedure for the management of a loose infected prosthesis

Introduction and purpose: Two-stage reimplantation of a hip replacement is the treatment of choice for deep periprosthetic infections. The purpose of this study is to analyse the survival of the femoral component in two-stage hip replacement reimplantations and compare the results of cemented and cementless components. Materials and methods: Between 1988 and 1998 our hospital carried out 169 two-stage reimplantations for treatment of first episodes of deep infection. The femoral component was cemented in 121 cases and cementless in 48. All patients were followed up clinically and radiologically for at least five years. Results: The two-stage revision was associated with a significant clinical improvement. The reinfection rate was 9% (16/169), of which 11 patients underwent revision surgery and five received chronic suppressive antibiotic treatment. Eight patients required revision due to aseptic loosening and two for periprosthetic fracture. With the numbers available, fixation with or without cement showed no significant differences. Conclusions: The two-stage revision of an infected hip prosthesis resolved the infection in 91% of the cases. An additional 5% required revision due to aseptic loosening. The surgical outcomes seem to be independent of the femoral component fixation (cemented or cementless)

Infection is a devastating complication following total hip arthroplasty. For chronically infected total hip arthroplasty; we utilise a 2-stage articulating antibiotic hip spacer technique. Our success rate with the technique is 90% with patients clinically free of infection at an average of five years postoperatively. 80% of the patients had a positive identification of the infecting organism. The other 20% had a positive frozen section and clinically infected joints. All patients receive a minimum of 6 weeks of intravenous antibiotics. Postoperative hip scores average 90 points. Some patients elected to keep their antibiotic spacers for up to 2 years before the 2nd stage. Advantages of this technique include improved patient function, maintenance of bone stock and soft tissue tension, thus simplifying reimplantation

Purpose: The gold standard for treatment of infected total hip or knee replacements remains a 2-stage exchange arthroplasty. This includes aggressive irrigation and debridement, implant removal, insertion of antibiotic impregnated spacers, iv antibiotics, and eventual reimplantion with a definitive prosthesis. The purpose of this study was to quantify Vancomycin and Gentamycin synovial fluid levels at the time of reimplantation following a 2-stage exchange arthroplasty for a infected total hip or knee replacements. Methods: The senior author performed 42 two-stage reconstructions using the prosthesis of antibiotic-loaded acrylic cement (PROSTALAC). Each 40g bag of Pala-cos-R cement was impregnated with Vancomycin 2g, Gentamycin 4.8g, and plus/minus ancef 2.0g (depending on penicillin allergy). At the time of reimplantation, the synovial fluid was immediately analyzed for levels of Vancomycin and Gentamycin. Results: 17 patients were taken for stage II within 60 days (avg. 53). The synovial fluid vancomycin and gentamycin levels were 12.7 and 20.6 respectively. Twelve patients had stage II between 60 and 90 days (avg. 79). The synovial fluid vancomycin and gentamycin levels were 6.2 and 14.9 respectively. The remaining 13 patients underwent stage II beyond 90 days (avg. 192), and their synovial fluid vancomycin and gentamycin levels were 3.3 and 2.4 respectively. 40 of 42 patients had their infections eradicated. Conclusions: in vitro evidence predicts that antibiotics elute rapidly from bone cement. The results of this study confirm that substantial doses of vancomycin, gentamycin, and ancef per bag of Palacos-R cement does confer long term synovial fluid antibiotic levels well above the minimal inhibitory concentrations required to treat infected total joints. When stage II reimplantation is done at greater than 3 months, synovial fluid antibiotic levels decline significantly

Prosthetic joint infections (PJI) occur in 0.8–1.9 % of arthroplasties, but the absolute number is increasing because of the frequency of procedures. Two stage exchange is the most effective strategy, but failures are often described. Culture of perioperative tissues during removal of arthroplasty is a standard procedure but culture during second step is equally important to define a success or a failure. We retrospectively reviewed PJI treated with two stage-exchange from January 2011 and December 2012 at “Ospedale S. Maria Misericordia”, Albenga-Italy. The procedure calls for bacterial culture not only during first step but also during reimplantation. Antibiotic treatment is prolonged after reimplantation until the cultures availability. A failure was defined by persistence of infection for positive culture or reocurrence of infection during a follow up of at least 2 years in patients with negative cultures. Three positive cultures yielding phenotypically identical organisms, or a single specimen of a virulent microorganism (e.g. Staphylococcus aureus) were required to rule out false positive for contaminants. Patients with persistence of infection were treated for 3 months with antibiotics. 86 patients underwent the two stage treatment: 45 hip and 41 knee prosthesis. The average ESR before arthroplasty removal was 59 mm/ 1st h (range 5–120), the average CRP was 3.9 mg/dl (range 0.3 – 34). Coagulase-negative staphylococci were isolated in 31 cases, Staphylococcus aureus in 19, Streptococcus spp in 8 and enterococci in 4. Gram-negatives were isolated in 4 patients and polymicrobial infection in 6 patients. In 14 patients (16%) no pathogen was identified. A positive culture during reimplantation was documented in 11 (13%) cases: 8 coagulase-negative staphylococci, 2 Staphylococcus aureus, 1 Candida sp. All patients received 3 months of therapy after surgery and 6 of them were free of infection at 2 years of follow up after the end of treatment. Among the 75 patients with negative cultures, a relapse was documented in 2 (3%), after 5 and 24 months, respectively. These cases were treated with arthrodesis and 6 weeks antibiotic treatment, with resolution of infection but poor functional results. Overall the success rate of our strategy was 92% (79/86). In patients treated with two-stage exchange, the combination of cultures at reimplantation and antibiotic suppressive treatment for 3 months in presence of positive cultures, are associated with a high rate of success. Only a prolonged follow up can rule out a relapse and agree with a true resolution of infection

Introduction and objective: Infection is one of the greatest threats in hip surgery. It is agreed that the implant should be removed. The debate remains open if one or two stage surgery is perferable. This study evaluates the two stage septic hip revison arthroplasty and compares our results with the literature. Materials and Methods: A retrospective clinical and radiological study was performed on patients that had a two stage septic revision hip surgery. The Harris Hip Score (HHS) and the Mayo Hip Score (MHS) were applied. The ASA-Score for evaluation of preoperative morbidity was introduced. Statistical evaluation included the t–test. Results: 40 patients with 41 primary total hip replacements underwent septic revision. 17 patients with 18 hip prostheses (8 male, 9 female) could be evaluated. 14 patients were deceased, the rest was unable to participate due to severe health problems.12 patientswith 13 hips had a primary reimplantation, 5 patients had to be left with a Girdlestone situation. The mean follow up was 52 months (4.3 years, standard error +/−28). The average age was 68 years. The mean preoperative ASA-Score was 3.24 (+/−0,75). Staph. aureus was the most common infectious agent (35%) followed by Staph epidermidis (24%) and E. coli (12%). The mean time between removal and re-implantation was 158 days. The most frequent primary preoperative indication for hip arthroplasty was osteoarthritis (62%) followed by trauma (24%) and avascular necorsis of the femoral head (14%). In 42%, the onset of ionfection was early (under 12 months after implantation), 58%% of the patients had a late onset infection. The MHS in the group who had a reimplantation was an average of 66/standard error +/−21). The patients with a Girdlestone situation had a HHS that was not significantly lower than the rest (58 in Girdlestone patients, 61 in patients with re-implantation). Discussion: The study demonstrated that our results compare well to those of other studies. It supports the conclusion that two stage septic hip arthroplasty is still an excellent option in septic revision arthroplasty. The preoperative ASA-Score which is not routinely mentioned in other studies showed that many of our patients were critically ill. This may explain the long interval between removal and reimplantation, and it may also be of value to determine wether to re-implant at all costs. This study remarkably demonstrated that patients with resection arthroplasty did not have a significantly lower HHS than those with performed re-implantation. The resection arthroplasty may be considered a valuable solution in clinically very ill patients according to our results. If a second operation considering the ASA -score would be too risky it should be discussed if reimplantation must be achieved

Acute periprosthetic infection, acute and chronic course of the infection with unknown spectrum of organism, hardly to treat and loss of mobility due to long lasting immobilization after implant removal are the indications for this special design of a spacer. The management of a bacterial periprosthetic infection by two-stage reimplantation using an implanted applicationspacer for antibiotics maintains mobility and soft tissue balance and ensures simultaneous local delivery of antibiotics. After a complete synovectomy the implant components and all foreign material are removed. The implant bed is then prepared for implantation of the application-spacer for antibiotics. Silicone catheters are advanced through two separate drill holes into the intramedullary canal and then inserted into the perforated implant stems. After the applicationspacer for antibioticss has been implanted, the wound is closed. Daily parenteral doses of antibiotics are delivered through the percutaneous silicone catheters directly into the intramedullary canal at the site of the infection. The applicationspacer for antibiotics allows daily physiotherapy and even mobilization on a CPM device. Partial weight bearing may even be allowed if there is sufficient stability. Once the CRP values have decreased to normal levels, the definitive implant is placed using antibiotic-impregnated cement according to current resistance studies. The implant beds are debrided to remove the synovial tissue that has developed in the interim. Then the revision implants can be placed in the prepared bone because the same templates are used for both the applicationspacer for antibioticss and the revision implants. 36 patients have been treated with this method since 1993. Two-stage reimplantation of a total knee was performed in 27 cases.. The longest postoperative follow-up period is now 12 years. Till now, no revision surgery has been required on a joint treated in this manner, and no periprosthetic infections have been observed. In the knee, a range of motion of 0/0/106 degrees was achieved after an average follow-up period of 7,1 years. In the hip, values of 10/0/110 degrees were achieved after an average of 7,3 years. Revision surgery for infection included cases of fungal and tubercular infection. A postoperative Hospital for Special Surgery rating of 79,5 was achieved in the knee and a rating of 81,3 in the Harris hip score