Septic Revision Total Knee Arthroplasty Research Articles

Intramedullary Positive Tissue Culture Increases the Risk of Reinfection Following One-Stage Septic Revision Total Knee Arthroplasty

BackgroundIntraoperative acquisition of representative tissue samples is essential during revision arthroplasty of the infected total knee arthroplasty (TKA). While the number of intraoperative tissue samples needed to identify the organism is well described in the literature, there is still a paucity of evidence regarding the location of positive intraoperative samples and their correlation to postoperative outcomes. MethodsThere were forty-two patients who had septic failure following one-stage revision TKA for periprosthetic joint infection who were identified between January 2009 and December 2017. They were matched to a control group of patients who had successful one-stage revision TKA without septic failure. The location of positive intraoperative tissue samples was categorized as: 1) soft tissue; 2) interface between bone and prosthesis; and 3) intramedullary (IM). Chi-square, Student’s t-, and Wilcoxon Mann-Whitney U-tests were used as appropriate. Univariate and multivariate logistic regression analyses were performed to evaluate predictors of septic failure. ResultsWeight > 100 kilograms (P = .033), higher Charlson Comorbidity Index (P < .001), and positive IM cultures (P < .001) were associated with a higher risk of reinfection after one-stage revision TKA. A positive IM sample carried a nearly five-fold increase in odds of reinfection (odds ratio 4.86, 95% confidence interval 1.85 to 12.78, P = .001). ConclusionsA positive IM culture sample is significantly associated with septic failure after one-stage exchange for periprosthetic joint infection of the knee. Patients who had positive IM cultures may benefit from longer postoperative antibiotic therapy for the treatment of one-stage exchange arthroplasty to minimize the risk of reinfection.

Clinical Outcomes and Complications of 2-Stage Septic Versus Aseptic Revision Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

Although several studies have compared the clinical outcomes of septic and aseptic revision total knee arthroplasty (TKA), their results have been controversial. Therefore, this study aimed to compare clinical outcomes and complications of septic and aseptic revision TKA through a systematic review and meta-analysis. The PubMed (MEDLINE) and Embase databases were searched for studies evaluating the clinical outcomes and complications of 2-stage septic revision and aseptic revision TKAs. A systematic review of clinical outcomes (Knee Society Knee and Function Scores and range of motion) and complications (reoperation, infection, and failure rates) was conducted. Thirteen studies were included in the systematic review. The mean MINORS (Methodological Index for NOn-Randomized Studies) score of the included studies was 20.5 (range, 18 to 22). The meta-analysis revealed higher reoperation (risk ratio [RR], 1.98; 95% confidence interval [CI], 1.50 to 2.62; p < 0.00001), infection (RR, 4.08; 95% CI, 2.94 to 5.64; p < 0.00001), and failure rates (RR, 2.88; 95% CI, 1.38 to 6.03; p = 0.005) in septic revision TKAs than in aseptic revision TKAs. Moreover, septic revision TKAs showed lower Knee Society Knee Scores compared with aseptic TKAs (mean difference [MD], -6.86; 95% CI, -11.80 to -1.92; p = 0.006). However, the Knee Society Function Score (MD, -1.84; 95% CI, -7.84 to 3.80; p = 0.52) and range of motion (MD, -6.96°; 95% CI, -16.23° to 2.31°; p = 0.14) were not significantly different between septic and aseptic revision TKAs. Despite the heterogeneity of prosthesis designs and surgical protocols used in septic and aseptic revision TKAs, the results of this systematic review suggest that 2-stage septic revision TKAs have poorer clinical outcomes and higher complication rates than aseptic revision TKAs do. Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Maintenance of the joint line and posterior condylar offset are the most notable variables for successful outcomes of revision total knee arthroplasty.

Controversy regarding which variables should be prioritized for better outcomes in revision total knee arthroplasty (RTKA) exists. This study aimed to comprehensively analyze the variables affecting RTKA outcomes. We retrospectively identified 87 RTKAs in 82 patients who were performed between March 2014 and February 2020. Range of motion (ROM), including flexion contracture (FC) and further flexion (FF), was analyzed according to the covariates. The covariates included mode of failure, joint line position, anteroposterior (AP) position, rotational alignment of the femoral component, and patellofemoral alignment. The differences between the final follow-up values of each RTKA variable and those of the native knee were evaluated. The clinical outcomes were evaluated. No significant differences were observed between the joint line positions of the RTKA and native knees. The patellar and AP positions of the femoral component were restored to pre-TKA values. The femoral component had an external rotation of 2.78° compared with the native knee. In multivariable stepwise regression analysis, restoration of the adductor tubercle joint line and posterior condylar offset (PCO) were significant variables affecting ROM. Septic RTKA (33 knees) resulted in poor FF outcomes (p = 0.030) and Western Ontario and McMaster Universities Osteoarthritis Index stiffness (WOMAC S) scores (p < 0.001), compared with aseptic RTKA (54 knees). Restoration of the joint line position and PCO are crucial factors for improved ROM in RTKA. Joint line elevation in RTKA resulted in worse ROM than joint line lowering. In addition, RTKA due to septic failure had inferior ROM and WOMAC S scores compared with RTKA due to aseptic failure. Level III, cohort study.

Inferior results at long-term follow-up after extensor mechanism allograft reconstruction in septic compared to aseptic revision total knee arthroplasty.

Extensor mechanism lesion after total knee arthroplasty (TKA) is a catastrophic complication. Reconstruction with extensor mechanism allograft (EMA) has been described as a sound salvage procedure. Its effectiveness at long term and in septic cases is still under scrutiny. The long-term results of EMA reconstruction for chronic extensor mechanism failures following aseptic and septic revision TKA have been analysed. From the institutional database, 35 patients with a revision TKA (RevTKA) undergoing EMA reconstruction from 2005 to 2015 have been retrospectively identified. A history of periprosthetic joint infection (PJI) was found in 13 (37%) patients. The mean follow-up was 81.2months (± 34.7, range 3-120). EMA failures were considered for lag more than 20°, Knee Society Score (KSS) less than 60 points, and/or in the case of revision of the allograft. The mean KSS improved from 35.9 (± 16.9, range 0-54) to 86.6 (± 10.4, range 54-99) points in the aseptic group (p < 0.001) and from 27.5 (± 11.6, range 10-44) to 79.4 (± 16.3, range 48-94) points in the septic group (p < 0.001). The extensor lag changed from 48.4° (± 14.5, range 30-90) to 4.6° (± 10.8, range 0-50) in the aseptic group (p < 0.001) and from 56.5° (± 20.8, range 30-90) to 6.1° (± 6.8, range 0-20) in the septic group (p < 0.001). The mean postoperative flexion was 105.2° (± 13.2, range 75-130) in the aseptic group and 102.7° (± 12.5, range 80-120) in the septic group (p = 0.32). Three failures (14% of the cases) occurred in the aseptic group and five in the septic group (38% of the cases). The overall survivorship at 10 years was 83.3% (22 cases, CI95 94.2-121.7) vs 58% (13 cases, CI95 67.2-111.7) in the aseptic and septic group, respectively (p = 0.01). EMA reconstruction after extensor mechanism disruptions in TKA is a reliable salvage procedure. The septic nature of the revision decreased the functionality of the knee joint after EMA, but it did not represent a risk factor for re-ruptures or recurrence of infection. Level III.

Clinical Outcomes and Infection Rates Following Revision Total Knee Arthroplasty: Aseptic Failure versus Septic Failure.

It is controversial whether revision total knee arthroplasty (TKA) due to septic failure shows inferior clinical outcomes compared with TKA due to aseptic failure. Moreover, few studies have compared the infection rates after revision TKA between aseptic and septic failure. We aimed to compare the clinical outcomes and infection rates after aseptic and septic revision TKA. Between April 2006 and May 2019, 68 and 26 patients underwent revision TKA due to aseptic failure (aseptic group) and septic failure (septic group), respectively. The postoperative range of motion (ROM), Western Ontario and McMaster Universities Osteoarthritis index, Knee Society Knee Score (KSKS), Knee Society Function Score (KSFS), and infection rates were compared between the two groups. The mean follow-up durations in the aseptic and septic groups were 44.4 and 54.8 months, respectively. The septic group showed inferior postoperative ROM (124.1° and 109.4°, p = 0.004), KSKS (88.9 and 78.8, p = 0.001), and KSFS (72.8 and 59.0, p = 0.001). Three patients of aseptic group had infection. Three patients of septic group had recurred infection (same pathogen with the first infection) and 1 patient had a new infection (different pathogen). The septic group showed slightly higher but not significantly different infection rates (4.4% and 15.4%, p = 0.089). Revision TKA with septic failure showed inferior postoperative clinical outcomes compared with aseptic revision surgery. A slightly higher infection rate was observed in the septic group but it was not significantly different.

Significant Difference in Antimicrobial Resistance of Coagulase Negative Periprosthetic Joint Infection in Septic Revision Total Knee Arthroplasty Between Two Major Orthopedic Centers.

Antimicrobial resistance is recognized as a major public health threat. It occurs naturally; however, an excessive antibiotic use and misuse of antibiotics accelerate the process. Periprosthetic joint infections (PJI) are becoming harder to treat as the efficacy of antibiotics is becoming lower. The aim of this study was to compare the resistance of coagulase-negative staphylococci (CNS) to antibiotics identified after revision TKAs for PJI between two major orthopedic centers. A review of all revision TKAs, undertaken between 2006 and 2018 in two orthopedic centers, was performed, including all those meeting the consensus criteria for PJI, in which CNS were identified. There were no major differences in surgical approach and tissue sampling between both centers. Thirteen commonly used antibiotics were tested at both centers. The 132 strains were analyzed for their resistance to 13 different antibiotics. Staphylococcus epidermidis was identified in 70.5% cultures, followed by Staphylococcus capitis in 8.3% cultures. The comparison of antibiotic resistance between two centers was statistically significant to penicillin (P= .001), oxacillin (P= .011), cefuroxime (P= .044), levofloxacin (P= .006), moxifloxacin (P= .008), tetracycline (P < .001), rifampicin (P < .001) and vancomycin (P < .001). The difference of resistance of CNS was not statistically significant to fosfomycin, clindamycin, teicoplanin, erythromycin and ampicillin. The resistance of CNS to antibiotics differs significantly between two major orthopedic centers that are geographically fairly close. Monitoring of bacteriological analyses in each referral center should be continuously performed. Close monitoring is needed for more efficient antibiotic treatment of and prophylaxis against PJI.

High Mortality After Total Knee Arthroplasty Periprosthetic Joint Infection is Related to Preoperative Morbidity and the Disease Process but Not Treatment

BackgroundPeriprosthetic joint infection (PJI) mortality rate is approximately 20%. The etiology for high mortality remains unknown. The objective of this study was to determine whether mortality was associated with preoperative morbidity (frailty), sequalae of treatment, or the PJI disease process itself. MethodsA multicenter observational study was completed comparing 184 patients treated with septic revision total knee arthroplasty (TKA) to a control group of 38 patients treated with aseptic revision TKA. Primary outcomes included time and the cause of death. Secondary outcomes included preoperative comorbidities and Charlson Comorbidity Index (CCMI) measured preoperatively and at various postoperative timepoints. ResultsThe septic revision TKA cohort experienced earlier mortality compared to the aseptic cohort, with a higher mortality rate at 90 days, 1, 2, and 3 years after index revision surgery (P = .01). There was no significant difference for any single cause of death (P > .05 for each). The mean preoperative CCMI was higher (P = .005) in the septic revision TKA cohort. Both septic and aseptic cohorts experienced a significant increase in CCMI from the preoperative to 3 years postoperative (P < .0001 and P = .002) and time of death (P < .0001 both) timepoints. The septic revision TKA cohort had a higher CCMI 3 years postoperatively (P = .001) and at time of death (P = .046), but not one year postoperatively (P = .119). ConclusionCompared to mortality from aseptic revision surgery, septic revision TKA is associated with earlier mortality, but there is no single specific etiology. As quantified by changes in CCMI, PJI mortality was associated with both frailty and the PJI disease process, but not treatment.

High revision rates following repeat septic revision after failed one-stage exchange for periprosthetic joint infection in total knee arthroplasty.

The outcome of repeat septic revision after a failed one-stage exchange for periprosthetic joint infection (PJI) in total knee arthroplasty (TKA) remains unknown. The aim of this study was to report the infection-free and all-cause revision-free survival of repeat septic revision after a failed one-stage exchange, and to determine whether the Musculoskeletal Infection Society (MSIS) stage is associated with subsequent infection-related failure. We retrospectively reviewed all repeat septic revision TKAs which were undertaken after a failed one-stage exchange between 2004 and 2017. A total of 33 repeat septic revisions (29 one-stage and four two-stage) met the inclusion criteria. The mean follow-up from repeat septic revision was 68.2 months (8.0 months to 16.1 years). The proportion of patients who had a subsequent infection-related failure and all-cause revision was reported and Kaplan-Meier survival for these endpoints was determined. Patients were categorized according to the MSIS staging system, and the association with subsequent infection was analyzed. At the most recent follow-up, 17 repeat septic revisions (52%) had a subsequent infection-related failure and the five-year infection-free survival was 59% (95% confidence interval (CI) 39 to 74). A total of 19 underwent a subsequent all-cause revision (58%) and the five-year all-cause revision-free survival was 47% (95% CI 28 to 64). The most common indication for the first subsequent aseptic revision was loosening. The MSIS stage of the host status (p = 0.663) and limb status (p = 1.000) were not significantly associated with subsequent infection-related failure. Repeat septic revision after a failed one-stage exchange TKA for PJI is associated with a high rate of subsequent infection-related failure and all-cause revision. Patients should be counselled appropriately to manage expectations. The host and limb status according to the MSIS staging system were not associated with subsequent infection-related failure. Cite this article: Bone Joint J2022;104-B(3):386-393.

Significant Difference in Antimicrobial Resistance of Bacteria in Septic Revision between Total Knee Arthroplasty and Total Hip Arthroplasty.

Antimicrobial resistance (AMR) aggravates the already difficult treatment of periprosthetic joint infections (PJI). Due to many factors influencing AMR, the correct choice of antimicrobial management remains arguable. The primary purpose of this retrospective study was to identify and compare bacteria and their antibiotic resistance profile between septic revision total knee arthroplasty (TKA) and septic revision total hip arthroplasty (THA). A review of all revision TKAs and revision THAs, undertaken between 2007 and 2020 in a tertiary referral hospital, was performed. Included were cases meeting the consensus criteria for PJI, in which an organism has been identified. There were no major differences in tissue sampling between revision TKAs and revision THAs over time. A total of 228 bacterial strains, isolated after revision TKA and THA, were analysed for their resistance to 20 different antibiotics. There was a statistically significant higher occurrence of Gram-negative bacteria identified after revision THAs compared to TKA (p = 0.002). The comparison of antibiotic resistance between revision TKAs and revision THAs was statistically significant in 9 of 20 analysed antibiotics. This has implications for the choice of empirical antibiotic in revision surgery as well as prophylactic antibiotic in primary surgery, depending on the joint that is to be replaced.

Trends in Hospital and Surgeon Charges and Reimbursements for Revision Total Knee Arthroplasty

BackgroundThe relationship between surgeon and hospital charges and reimbursements for revision total knee arthroplasty (TKA) has not been well examined. The objective of this study is to report trends and variations in hospital charges and payments compared to surgeons for stage 1 (S1) vs stage 2 (S2) septic revision TKA and aseptic revision (AR) TKA. MethodsThe 5% Medicare sample was used to capture hospital and surgeon data for revision TKA from 2005 to 2014. The charge multiplier (CM) and ratio of hospital to surgeon charges, and the payment multiplier (PM) and ratio of hospital to surgeon payments were calculated. Year-to-year variation and regional trends in-patient demographics, Charlson Comorbidity Index, length of stay (LOS), CM, and PM were evaluated. ResultsIn total, 4570 AR, 1323 S1, and 863 S2 TKA patients were included. CM increased for all cohorts: 8.1-13.8 for AR (P < .001), 21.0-22.5 (P = .07) for S1, and 11.8-22.0 (P < .001) for S2. PM followed a similar trend, increasing 8.1-13.8 (P < .001) for AR, 19.8-27.3 (P = .005) for S1, and 14.7-30.7 (P < .001) for S2. Surgeon reimbursement decreased for all cohorts. LOS decreased for AR (3.8-2.8 days), S1 (12.8-6.9 days), and S2 (4.5-3.9 days). Charlson Comorbidity Index remained stable for AR patients but increased significantly for S1 and S2 cohorts. ConclusionHospital charges and payments relative to the surgeons have significantly increased for revision TKA in the setting of stable or increasing patient complexity and decreasing LOS.

Septic Revision Total Knee Arthroplasty Is Associated With Significantly Higher Mortality Than Aseptic Revisions: Long-Term Single-Center Study (1254 Patients)

BackgroundThe aim of this study is to examine the differences in long-term mortality rates between septic and aseptic revision total knee arthroplasty (rTKA) in a single specialist center over 17-year period. MethodsRetrospective consecutive study of all patients who underwent rTKA at our tertiary center between 2003 and 2019 was carried out. Revisions were classified as septic or aseptic. We identified patients’ age, gender, American Society of Anesthesiologists grade, and body mass index. The primary outcome measure was all-cause mortality at 5 years, 10 years, and over the whole study period of 17 years. Death was identified through both local hospital electronic databases and linked data from the National Joint Registry/NHS Personal Demographic Service. Kaplan-Meier survival curves were used to estimate time to death. ResultsIn total, 1298 consecutive knee revisions were performed on 1254 patients (44 bilateral revisions) with 985 aseptic revisions in 945 patients (75.4%) and 313 septic revisions in 309 patients (24.6%). Average age was 70.6 years (range 27-95) with 720 females (57.4%). Septic revisions had higher mortality rates; patients’ survivorship for septic vs aseptic revisions was 77.6% vs 89.5% at 5 years, 68.7% vs 80.2% at 10 years, and 66.1% vs 75.0% at 17 years; these differences were all statistically significant (P < .0001). The unadjusted 10-year risk ratio of death after septic revision was 1.59 (95% confidence interval 1.29-1.96) compared to aseptic revisions. ConclusionrTKA performed for infection is associated with significantly higher long-term mortality at all time points compared with aseptic revision surgery. Level of EvidenceLevel IV.

Medicare Physician Fee Reimbursement for Revision Total Knee Arthroplasty Has Not Kept Up with Inflation from 2002 to 2019.

As orthopaedic physician fees continue to come under scrutiny by the U.S. Centers for Medicare & Medicaid Services (CMS), there is a continued need to evaluate trends in reimbursement rates across contemporary time intervals. Although substantially lower work relative value units (RVUs) have been previously demonstrated for septic revision total knee arthroplasty (TKA) compared with aseptic revisions, to our knowledge, there has been no corresponding analysis comparing total physician fees. Therefore, the purpose of our study was to analyze temporal trends in Medicare physician fees for septic and aseptic revision TKAs. Current Procedural Terminology (CPT) codes related to septic 1-stage and 2-stage revision TKAs and aseptic revision TKAs were categorized. From 2002 to 2019, the facility rates of physician fees associated with each CPT code were obtained from the CMS Physician Fee Schedule Look-Up Tool. Monetary data from Medicare Administrative Contractors at 85 locations were used to calculate nationally representative means. All total physician fee values were adjusted for inflation and were translated to 2019 U.S. dollars using Consumer Price Index data from the U.S. Bureau of Labor Statistics. Cumulative annual percentage changes and compound annual growth rates (CAGRs) were computed utilizing adjusted physician fee data. After adjusting for inflation, the total mean Medicare reimbursement (and standard deviation) for aseptic revision TKA decreased 24.83% ± 3.65% for 2-component revision and 24.21% ± 3.68% for 1-component revision. The mean septic revision TKA total Medicare reimbursement declined 23.29% ± 3.73% for explantation and 33.47% ± 3.24% for reimplantation. Both the dollar amount (p < 0.0001) and the percentage (p < 0.0001) of the total Medicare reimbursement decline for septic revision TKA were significantly greater than the decline for aseptic revision TKA. Septic revision TKAs have been devalued at a rate greater than their aseptic counterparts over the past 2 decades. Coupled with our findings, the increased resource utilization of septic revision TKAs may result in financial barriers for physicians and subsequently may reduce access to care for patients with periprosthetic joint infections. The devaluation of revision TKAs may result in reduced patient access to infection management at facilities unable to bear the financial burden of these procedures.

In-hospital Mortality after Septic Revision TKA: Analysis of the New York and Florida State Inpatient Databases.

The aims of this study were to investigate (1) in-hospital mortality rates following septic revision total knee arthroplasty (rTKA); (2) compare septic rTKA mortality rates between differing knee revision volume (KRV) hospitals; and (3) identify independent risk factors associated with in-hospital mortality after septic rTKA (up to 2-year follow-up). The Healthcare Cost and Utilization Project State Inpatient Databases of New York and Florida were used to identify septic rTKA, and control groups of aseptic rTKA and primary TKA between 2007 and 2012 via International Classification of Diseases, Ninth Revision codes. Mortality was compared between septic rTKA and aseptic rTKA/primary TKA control groups. Hospital KRV was stratified, and independent risk factors of in-hospital mortality were identified and analyzed using unadjusted and adjusted logistic regression analyses. In this study, 3,531 septic rTKA patients were identified; 105 (3%) patients suffered in-hospital mortality, compared with the control aseptic rTKA (n = 178; 1.7%; p < 0.0001) and primary TKA groups (n = 930; 0.6%; p < 0.0001). Being an octogenarian (adjusted odds ratio [AOR]: 2.361; 95% confidence interval [CI]: 1.514-3.683; p < 0.0002) and having a medium- or high-Elixhauser comorbidity score was associated with in-hospital mortality (AOR: 2.073; 95% CI: 1.334-3.223; p = 0.0012, and AOR: 4.127; 95% CI: 2.268-7.512, p < 0.0001). There were no significant in-hospital mortality rate differences in high- versus medium- versus low-KRV hospitals (1.9 vs. 3.6 vs. 2.9%, respectively, p = 0.0558). Age >81 years and higher comorbidity burden were found to contribute to increased risk of 2-year postoperative mortality after septic rTKA. This association could not be established for hospital KRV.

Combined serum biomarker analysis shows no benefit in the diagnosis of periprosthetic joint infection

PurposeIn many cases, the diagnosis of a periprosthetic joint infection (PJI) consisting of the clinical appearance, laboratory tests, and other diagnostic tools remains a difficult task. Single serum biomarkers are easy to collect, are suitable for periodical assessment, and are a crucial tool in PJI diagnosis, but limited sensitivity or specificity is reported in literature. The aim of this study was to combine the best-performing single serum biomarkers into a multi-biomarker model aiming to improve the diagnostic properties.MethodsWithin a 27-month period, 124 surgical procedures (aseptic or septic revision total knee arthroplasty (TKA) or total hip arthroplasty (THA)) were prospectively included. The serum leukocyte count, C-reactive protein (CRP), interleukin-6, procalcitonin, interferon alpha, and fibrinogen were assessed 1 day prior to surgery. Logistic regression with lasso-regularization was used for the biomarkers and all their ratios. After randomly splitting the data into a training (75%) and a test set (25%), the multi-biomarker model was calculated and validated in a cross-validation approach.ResultsCRP (AUC 0.91, specificity 0.67, sensitivity 0.90, p value 0.03) and fibrinogen (AUC 0.93, specificity 0.73, sensitivity 0.94, p value 0.02) had the best single-biomarker performances. The multi-biomarker model including fibrinogen, CRP, the ratio of fibrinogen to CRP, and the ratio of serum thrombocytes to CRP showed a similar performance (AUC 0.95, specificity 0.91, sensitivity 0.72, p value 0.01).ConclusionIn this study, multiple biomarkers were tested for their diagnostic performance, with CRP and fibrinogen showing the best results regarding the AUC, accuracy, sensitivity, and specificity. It was not possible to further increase the diagnostic accuracy by combining multiple biomarkers using sophisticated statistical methods.

Greater Prevalence of Mental Health Conditions in Septic Revision Total Knee Arthroplasty: A Call to Action.

The purpose of this study was to compare the prevalence of mental health conditions among patients undergoing (1) primary total knee arthroplasty (pTKA), (2) septic revision total knee arthroplasty (rTKA), and (3) aseptic revision total knee arthroplasty (TKA). The State Inpatient Databases were queried for all TKAs from 2005 to 2014 yielding 563,144 patients. Patients were separated into the following cohorts: primary, septic revision, and aseptic revision. Diagnoses of any mental health condition and the following specific conditions were compared between the three cohorts: schizophrenia/delusion, bipolar disorder, depression/mood disorder, personality disorder, anxiety/somatic/dissociative disorder, eating disorders, attention deficit hyperactivity disorder/conduct/impulse control, alcohol abuse, and drug abuse. Throughout the study period, an increase in the prevalence of mental health conditions was observed in septic and aseptic revision patients. Overall, there was a significantly higher prevalence of mental health conditions in the septic revision cohort (22.7%) compared with the primary (17.8%, p < 0.001) and aseptic revision (20.0%, p < 0.001) cohorts. Specifically, septic revision TKA patients had a higher prevalence of depression (p < 0.001), alcohol abuse (p < 0.001), drug abuse (p < 0.001), schizophrenia (p = 0.0007), and bipolar disorder (p < 0.001), compared with primary TKA patients. Additionally, there was a significantly higher prevalence of depression (p < 0.001), alcohol abuse (p < 0.001), and drug abuse (p < 0.001) among septic revision patients compared with aseptic revision patients. Mental health conditions were significantly higher among septic revision patients. Alcohol and drug abuse were approximately twice as prevalent in septic revision patients compared with primary and aseptic revision patients. These findings should serve as a call to action for mental health support for patients suffering from PJI.

Septic Revision Total Knee Arthroplasty: Treatment of Metaphyseal Bone Defects Using Metaphyseal Sleeves

BackgroundBone loss is a severe problem in septic revision total knee arthroplasty (RTKA). The use of porous coated metaphyseal sleeves is a promising treatment option for metaphyseal bone defects. The currently published midterm results remain limited and no study has been focused exclusively on septic cases. Our aim was to determine the implant survivorship (with special focus on osseointegration) and the clinical and radiological midterm outcome of metaphyseal sleeve fixation in septic RTKA surgery (minimum follow-up of 2 years). MethodsWe performed a clinical and radiographic examination of 56 patients with a history of prosthetic joint infection who underwent 2-stage RTKA with the use of porous coated metaphyseal sleeves. These examinations included evaluation of the American Knee Society Score, the Western Ontario and McMaster Universities Osteoarthritis Index, the Short Form (SF-36) Health survey as well as radiographic measurement to determine whether successful osseointegration had been achieved. ResultsNine patients (16%) had to be re-revised at the time of follow-up (mean, 5.3 years; range, 2-11.2), all due to reinfection. We did not encounter any cases of aseptic loosening. The mean range of motion (92°, SD ± 21°), subjective satisfaction score (7, SD ± 2), American Knee Society Score (76, SD ± 19), Western Ontario and McMaster Universities Osteoarthritis Index (70, SD ± 20), SF-36 mental component summary (55, SD ± 14), and SF-36 physical component summary (35, SD ± 9) have shown satisfying results. ConclusionMetaphyseal sleeves have shown very promising midterm results regarding clinical scores, osseointegration, and aseptic loosening. Our results are the first analyzing exclusively septic indications and indicate that they are a reliable fixation option in all bone defect types in septic RTKA patients.

Periprosthetic Joint Infection Does Not Preclude Good Outcomes after a Revision Total Knee Arthroplasty: A 7-Year Follow-Up Study of 144 Retrospective Cases

Background and Purpose Debate exists on whether septic revision total knee arthroplasty (TKA) results in inferior clinical outcomes, and limited information is available regarding the factors associated with such outcomes. This study aimed to (1) compare clinical outcomes and characteristics of aseptic versus septic revision TKA and (2) identify the risk factors associated with inferior clinical outcomes. Methods We retrospectively reviewed 144 revision TKAs (90 aseptic and 54 septic revisions) that were followed for a minimum of 3 years (mean = 7 years). Clinical outcome data, namely, Knee Society knee and function scores and the Hospital for Special Surgery knee score, were collected. We reviewed 13 pre- and intraoperative variables. Results Postoperative clinical outcomes were inferior in septic revision surgeries (p<0.05). In regression analyses, however, septic revision was not an independent risk factor for poor clinical outcomes. The independent risk factors for poor outcome were identified where Anderson Orthopedic Research Institute grade 3 femoral and tibial bone defects, more than three surgeries, and treatment for persistent infection were associated with inferior clinical outcomes (all p<0.05). Standard two-stage septic revision without grade 3 bone defects or additional surgeries showed comparable outcomes to aseptic revision. Interpretation Clinical outcomes of septic revision were inferior to those of aseptic revision. However, poor outcomes were mainly associated with large bone defects and an increased number of surgeries. The outcomes of aseptic and septic revision surgery were similar when patients with larger bone defects and more than three surgeries were excluded.

The Varus-Valgus Constrained Knee Implant: Survivorship and Outcomes.

The purpose of this study was to estimate the survivorship of the varus-valgus constrained (VVC) knee implants in primary, aseptic, and septic revision total knee arthroplasty (TKA); determine functional outcomes; main modes of failure; and variables associated with increased mechanical failures. In this study, 685 consecutive cases of primary (n = 247), aseptic (n = 315), and septic revision (n = 123) TKAs with VVC implants were performed between 1999 and 2008; 533 knees (78%) had a mean follow-up of 8.2 years (range, 2-15.1). Kaplan-Meier method was used to evaluate implant survival with mechanical failure as the end point. Clinical outcomes were measured with a modified Knee Society Score (mKSS) and modified Knee Function Score (mKFS) and modes of failure were determined. Cox proportional hazards models were performed to assess for factors associated with implant failure. Ten-year survival was 88.5% (95% confidence interval [CI]: 83.9-93.5%) for primary TKAs, 75.8% (95% CI: 70.4-81.7%) for aseptic, and 54.6% (95% CI: 43.7-68.2%) for septic revisions. Improvement in pre- to postoperative mKSS and mKFS were significant in all three groups (p < 0.05). The most common mode of failure overall was infection. Mechanical modes of failures included periprosthetic fracture (45%) for primary TKA and soft tissue instability (19%) for aseptic revisions. A longer period since the last surgery in affected knee was associated with lower mechanical failures (hazards ratio of 0.55 [95% CI: 0.31-0.95], p = 0.03). VVC implant showed reliable survivorship at 10 years although careful patient selection is warranted due to the risk of infection. The main mechanical modes of failure were instability and periprosthetic fracture.

The use of calcium carbonate beads containing gentamicin in the second stage septic revision of total knee arthroplasty reduces reinfection rate

BackgroundThe aim of the study was to analyze effectiveness and safety of packing the medullary canal of the tibia and femur with Herafill (Heraeus Medical GmbH, Wehrheim, Germany), a void filler and antibiotic carrier, during second stage revision total knee arthroplasty (TKA) for periprosthetic joint infection (PJI). MethodsTwo groups were formed of 28 consecutive patients during second stage revision TKA, comparable for gender and age. The study group received Herafill, while the control group did not. The average follow-up was 52months (minimum 36months). ResultsNo reinfections were observed in the study group, while five were seen in the control group. No other differences were observed between the study and control groups, including mean clinical KSS (Knee Society score) (67.4 and 68.4 points, respectively) and functional score (72.5 and 70.5 points respectively). No side effects related to the use of Herafill beads were noted. ConclusionsHerafill packed into the tibial and femoral intramedullary canal during second stage of septic revision TKA is a reliable bone substitute, may reduce recurrence of infection and incorporates well with host bone. However, results after PJI treatment are less than optimal measured by KSSs as compared to patients who do not require revision.

Aseptic versus septic revision total knee arthroplasty: Patient satisfaction, outcome and quality of life improvement

We prospectively compared the clinical outcomes and patient satisfaction rates of aseptic ( n = 30) versus septic revision TKA ( n = 15) at a mean follow-up of 40 months. We hypothesized that the clinical results of septic revision TKA would be inferior to aseptic revision TKA. The indication for revision in aseptic group was stiffness in 11 patients, aseptic loosening in 13, patellar loosening or maltracking in 6 patients. Patients operated for infection had better post-operative Knee Society Scores (KSS), Function Scores and SF-36 Mental Scores than aseptic group but there were no significant differences in the satisfaction rates. Patients operated for infection had more improvement in their KSS ( p = 0.004) and Function Scores ( p = 0.02) than patients revised for stiffness. Moreover, patients operated on for patellar problems had higher satisfaction rates than patients revised for stiffness ( p = 0.01) or aseptic loosening ( p = 0.01). Thus, patients undergoing septic revision TKA had better outcomes compared to those with aseptic revision TKA. However, in the aseptic group, revision TKA for stiffness was associated with the poorest outcomes. The indication for aseptic revision is an important variable when discussing treatment and outcome with patients.