ABSTRACT
BACKGROUND: Identification of infective organism causing periprosthetic joint infections (PJIs) is crucial to tailor the best combination of surgical and antimicrobial treatment. Traditional culture, with all its limitations, has been utilized for this purpose. A synovial fluid antibody assay against some common pathogens has been introduced by a commercial entity recently. This study aimed to determine if the antibody testing could be used as a proxy to traditional culture, and whether it provided additional information, in the setting of PJI. METHODS: A retrospective study was conducted of patients who underwent revision total hip and knee arthroplasty between January 2019 and 2020. Aspirated synovial fluid was sent for analyses including the commercial antibody testing. All patients had samples harvested for culture per standard of care. Results of the antibody testing and culture, in terms of concordance, were compared. Receiver operating characteristic curve and Youden's criterion were used to compare the 2 methods. RESULTS: A total of 419 patients were included. Using the International Consensus Meeting criteria as reference standard for PJI, antibody testing had a sensitivity and specificity of 40.5% and 93.4%, respectively. There were 59.5% false negative results with antibody testing compared with 50% for culture. Of the 12 patients who had positive results in both tests, 5 (41.7%) had discordant pathogens identified in each test. CONCLUSION: Synovial fluid antibody testing does not provide clinical benefit when compared to traditional cultures for PJI diagnosis. The antibody testing had a low sensitivity and a high rate of discordance with culture, when both tests were positive.
Subject(s)
Arthritis, Infectious , Arthroplasty, Replacement, Hip , Arthroplasty, Replacement, Knee , Prosthesis-Related Infections , Arthritis, Infectious/surgery , Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Knee/adverse effects , Biomarkers , Humans , Prosthesis-Related Infections/diagnosis , Prosthesis-Related Infections/surgery , Retrospective Studies , Sensitivity and Specificity , Synovial FluidABSTRACT
BACKGROUND: A leukocyte esterase (LE) test is inexpensive and provides real-time information about patients suspected of periprosthetic joint infections (PJIs). The 2018 International Consensus Meeting (ICM) recommends it as a diagnostic tool with a 2+ cutoff. There is still a lack of data revealing LE utility versus the ICM 2018 criteria for PJI. METHODS: This is a retrospective study of patients who underwent revision total hip and total knee arthroplasty at a single institution between March 2009 and December 2019. All patients underwent joint aspiration before the arthrotomy, and the LE strip test was performed on aspirated joint fluid. PJI was defined using the 2018 ICM criteria. RESULTS: As per the 2018 ICM criteria, 78 patients were diagnosed with chronic PJI and 181 were not infected. An LE test with a cutoff of ≥1+ had a sensitivity of 0.744, a specificity of 0.906, a positive predictive value of 0.773, an accuracy of 0.825 (95% confidence interval 0.772-0.878), and a negative predictive value of 0.891. The positive likelihood ratio (LR+) was 7.917. Using an LE cutoff of 2 + had a sensitivity of 0.513, a specificity of 1.000, and an accuracy of 0.756 (95% confidence interval-0.812). CONCLUSION: LE is a rapid and inexpensive test which can be performed at the bedside. Its performance is valuable as per ICM criteria. Based on the findings of this study and the given cohort, we suggest using the cutoff of LE1+ (result = negative or trace) as a point of care test to exclude infection, whereas LE at 2 + threshold has near absolute specificity for the diagnosis.
Subject(s)
Prosthesis-Related Infections , Biomarkers , Carboxylic Ester Hydrolases , Consensus , Humans , Prosthesis-Related Infections/diagnosis , Retrospective Studies , Sensitivity and Specificity , Synovial FluidABSTRACT
BACKGROUND: Although obesity is a risk factor for periprosthetic joint infection (PJI) after total knee arthroplasty (TKA), the role of soft tissue thickness (STT) at the surgical site has not been well studied. This study examined if increased STT in the medial and anterior aspects of the knee are independent risk factors for PJI. METHODS: A retrospective study was conducted on 206 patients who underwent 2-stage exchange arthroplasty for PJI from 2000 to 2015. They were matched 1:3 to a control group of primary, noninfected TKA patients with minimum 2 years infection-free survival by age, gender, age-adjusted Charlson Comorbidity Index, date of surgery, and body mass index (BMI). Two blinded orthopedic surgeons measured the medial STT from the medial aspect of the knee at the level of the joint line on an anteroposterior radiograph, and anterior STT 8 cm above the joint line on a lateral radiograph from the skin to the quadriceps tendon. RESULTS: Increased STT was significantly associated with a higher risk for PJI. The mean anterior STT was 29.74 ± 13.76 mm in the PJI group and 24.88 ± 9.76 mm in the control group. The mean medial STT was 42.42 ± 14.66 mm for PJI and 37.27 ± 12.51 mm for control. Both STT measurements were significantly higher in PJI cases with BMI <30 kg/m2 vs control patients with BMI <30 kg/m2. CONCLUSION: Anterior and medial knee STT was an independent risk factor for PJI after primary TKA and represents a simple radiographic method to assess postoperative infection risk. Excess adipose tissue around the surgical site can predispose patients to PJI after TKA regardless of BMI.
Subject(s)
Arthritis, Infectious , Arthroplasty, Replacement, Knee , Knee Prosthesis , Prosthesis-Related Infections , Arthritis, Infectious/surgery , Arthroplasty, Replacement, Knee/adverse effects , Humans , Knee Joint/surgery , Knee Prosthesis/adverse effects , Prosthesis-Related Infections/epidemiology , Prosthesis-Related Infections/etiology , Retrospective StudiesABSTRACT
BACKGROUND: Aspirin has been shown to be a safe and cost-effective thromboprophylaxis agent with equivalent preventive efficacy to warfarin and fewer side-effects. However, animal studies have suggested delayed bone healing with aspirin and other inhibitors of prostaglandin synthesis. The impact of aspirin on aseptic loosening following cementless total hip arthroplasty (THA) has yet to be explored. Our aim was to determine if patients receiving aspirin for thromboprophylaxis had higher rates of aseptic loosening vs patients receiving warfarin after THA. METHODS: We identified 11,262 consecutive primary uncemented THA performed between 2006 and 2017. Postoperatively, either warfarin (target international normalized ratio 1.5-2.0) or aspirin chemoprophylaxis were prescribed for 4 weeks. We recorded demographics, length of stay, body mass index, preoperative nonsteroidal antiinflammatory drug use, and Elixhauser comorbidity index. All revisions because of aseptic loosening within 1 year of the index procedure were identified radiographically, confirmed intraoperatively, and did not fulfill Musculoskeletal Infection Society criteria for periprosthetic infection. Multivariate logistic regression analysis was performed. RESULTS: There was no difference (P = .14) in the rates of revision for aseptic loosening between patients in the aspirin cohort (14/4530; 0.31%; P = .14) and the warfarin cohort (36/6682; 0.54%). After accounting for confounding variables, no significant difference was noted in aseptic loosening rates between patients treated with aspirin vs those treated with warfarin (adjusted odds ratio 0.51; P = .11). Perioperative nonsteroidal antiinflammatory drug was not significantly associated with aseptic loosening (adjusted odds ratio 1.20; P = .67). CONCLUSION: While multiple agents are available for venous thromboprophylaxis, there is increasing evidence in favor of the use of aspirin. This study allays the notion that aspirin increases the rates of aseptic loosening following uncemented hip arthroplasty.
Subject(s)
Arthroplasty, Replacement, Hip , Hip Prosthesis , Venous Thromboembolism , Anticoagulants/adverse effects , Arthroplasty, Replacement, Hip/adverse effects , Aspirin/adverse effects , Hip Prosthesis/adverse effects , Humans , Prosthesis Design , Prosthesis Failure , Reoperation , Risk FactorsABSTRACT
BACKGROUND: Value-based payment models such as bundled payments have been introduced to reduce costs following total hip arthroplasty (THA). Concerns exist, however, about access to care for patients who utilize more resources. The purpose of this study is thus to compare resource utilization and outcomes of patients undergoing THA for malignancy with those undergoing THA for fracture or osteoarthritis. METHODS: We queried the American College of Surgeons National Surgical Quality Improvement Program database to identify all hip arthroplasties performed from 2013 to 2016 for a primary diagnosis of malignancy (n = 296), osteoarthritis (n = 96,480), and fracture (n = 13,406). The rates of readmissions, reoperations, comorbidities, mortality, and surgical characteristics were compared between the 3 cohorts. To control for confounding variables, a multivariate analysis was performed to identify independent risk factors for resource utilization and outcomes following THA. RESULTS: Patients undergoing THA for malignancy had a longer mean operative time (155.7 vs 82.9 vs 91.0 minutes, P < .001), longer length of stay (9.0 vs 7.2 vs 2.6 days, P < .001), and were more likely to be discharged to a rehabilitation facility (42.1% vs 61.8% vs 20.2%, P < .001) than patients with fracture or osteoarthritis. When controlling for demographics and comorbidities, patients undergoing THA for malignancy had a higher rate of readmission (adjusted odds ratio 3.39, P < .001) and reoperation (adjusted odds ratio 3.71, P < .001). CONCLUSION: Patients undergoing THA for malignancy utilize more resources in an episode-of-care and have worse outcomes. Risk adjustment is necessary for oncology patients in order to prevent access to care problems for these high-risk patients.
Subject(s)
Arthroplasty, Replacement, Hip/mortality , Fractures, Bone/surgery , Neoplasms/surgery , Osteoarthritis/surgery , Postoperative Complications/epidemiology , Aged , Arthroplasty, Replacement, Hip/adverse effects , Cohort Studies , Comorbidity , Databases, Factual , Female , Fractures, Bone/mortality , Health Expenditures , Health Resources/economics , Humans , Male , Middle Aged , Multivariate Analysis , Neoplasms/mortality , Odds Ratio , Operative Time , Osteoarthritis/mortality , Patient Discharge , Postoperative Complications/etiology , Quality Improvement , Reoperation/statistics & numerical data , Risk Adjustment , Risk Factors , United States/epidemiologyABSTRACT
BACKGROUND: One of the most effective prophylactic strategies against periprosthetic joint infection (PJI) is administration of perioperative antibiotics. Many orthopedic surgeons are unaware of the weight-based dosing protocol for cefazolin. This study aimed at elucidating what proportion of patients receiving cefazolin prophylaxis are underdosed and whether this increases the risk of PJI. METHODS: A retrospective study of 17,393 primary total joint arthroplasties receiving cefazolin as perioperative prophylaxis from 2005 to 2017 was performed. Patients were stratified into 2 groups (underdosed and adequately dosed) based on patient weight and antibiotic dosage. Patients who developed PJI within 1 year following index procedure were identified. A bivariate and multiple logistic regression analyses were performed to control for potential confounders and identify risk factors for PJI. RESULTS: The majority of patients weighing greater than 120 kg (95.9%, 944/984) were underdosed. Underdosed patients had a higher rate of PJI at 1 year compared with adequately dosed patients (1.51% vs 0.86%, P = .002). Patients weighing greater than 120 kg had higher 1-year PJI rate than patients weighing less than 120 kg (3.25% vs 0.83%, P < .001). Patients who were underdosed (odds ratio, 1.665; P = .006) with greater comorbidities (odds ratio, 1.259; P < .001) were more likely to develop PJI at 1 year. CONCLUSION: Cefazolin underdosing is common, especially for patients weighing more than 120 kg. Our study reports that underdosed patients were more likely to develop PJI. Orthopedic surgeons should pay attention to the weight-based dosing of antibiotics in the perioperative period to avoid increasing risk of PJI.
Subject(s)
Anti-Bacterial Agents/administration & dosage , Antibiotic Prophylaxis/statistics & numerical data , Arthritis, Infectious/prevention & control , Cefazolin/administration & dosage , Obesity/complications , Prosthesis-Related Infections/prevention & control , Adult , Aged , Arthritis, Infectious/etiology , Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Knee/adverse effects , Comorbidity , Female , Humans , Male , Middle Aged , Odds Ratio , Prosthesis-Related Infections/etiology , Retrospective Studies , Risk FactorsABSTRACT
BACKGROUND: Revision total joint arthroplasties (TJAs) have been empirically associated with significant postoperative morbidity and mortality. Red blood cell distribution width (RDW), a frequently measured hematological parameter, has been shown to predict mortality in hip fracture patients. However, its utility in risk-stratifying patients before revision TJA remains unknown. The aim of this study was to investigate the possible relationship between preoperative RDW levels and outcome of revision arthroplasty in terms of mortality, adverse outcomes, and length of hospital stay. METHODS: A single-institution retrospective study was conducted on 4633 patients who underwent revision TJA (3289 hips and 1344 knees) between 2000 and September 2016. Of those, 656 (14.1%) surgeries were performed due to periprosthetic joint infection, and 3977 (85.9%) were aseptic revisions. The association between preoperative RDW and various outcomes, including 1-year mortality, in-hospital medical complications, length of hospital stay, and 90-day all-cause readmission, was examined. RESULTS: The average age of patients in the cohort was 65.4 ± 12.9 years. The average Charlson comorbidity index was 0.6 (standard deviation = 1.0), with 691 patients (14.9%) having 2 or more comorbidities. Mean preoperative RDW level was 14.4% (standard deviation = 1.8). After adjusting for covariates, higher RDW levels were statistically significantly associated with mortality (adjusted odds ratio [OR], 1.25; 95% confidence interval [CI], 1.13-1.39; P < .001), any in-hospital medical complications (adjusted OR, 1.12; 95% CI, 1.07-1.18; P < .001), and readmission (adjusted OR, 1.07; 95% CI, 1.02-1.13; P < .001). CONCLUSION: Higher levels of preoperative RDW appeared to be associated with less optimal outcomes after revision TJA. Adult reconstruction orthopedic surgeons should be aware of this predictive factor and exercise caution with TJA revision patients with high values of preoperative RDW. RDW could be included in the routine perioperative workup and used to counsel patients on their postoperative risk.
Subject(s)
Arthroplasty, Replacement, Hip/mortality , Arthroplasty, Replacement, Knee/mortality , Erythrocyte Indices , Postoperative Complications/blood , Reoperation/mortality , Aged , Arthritis, Infectious/etiology , Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Knee/adverse effects , Cohort Studies , Comorbidity , Female , Humans , Length of Stay , Male , Middle Aged , Multivariate Analysis , Odds Ratio , Philadelphia/epidemiology , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Reoperation/adverse effects , Retrospective StudiesABSTRACT
BACKGROUND: The association between inadequate glycemic control and surgical site infection (SSI) following total joint arthroplasty (TJA) remains unclear. The aim of this study is to assess the relationship between perioperative glycemic control and the risk for SSI, mainly periprosthetic joint infection. METHODS: We searched OVID-MEDLINE, Embase, and Web of Science from inception up to June 2017. The main independent variable was glycemic control as defined by glycated hemoglobin (HbA1C) or perioperative glucose values. The main outcome was SSI. Publication year, location, study design, sample population (size, age, gender), procedure, glycemic control assessment, infection outcome, results, confounders, and limitations were assessed. Studies included in the meta-analysis had stratified glycemic control using a distinct HbA1C cut-off. RESULTS: Seventeen studies were included in this study. Meta-analysis of 10 studies suggested that elevated HbA1C levels were associated with a higher risk of SSI after TJA (pooled odds ratio 1.49, 95% confidence interval 0.94-2.37, P = .09) with significant heterogeneity between studies (I2 = 81.32%, P < .0001). In a subgroup analysis of studies considering HbA1C with a cut-off of 7% as uncontrolled, this association was no longer noticed (P = .50). All 5 studies that specifically assessed for SSI and perioperative hyperglycemia showed a significant association, which was usually attenuated after adjusting for covariates. CONCLUSION: Inadequate glycemic control was associated with increased risk for SSI after TJA. However, the optimal HbA1C threshold remains contentious. Pooled data does not support the conventional 7% cut-off for risk stratification. Future studies should examine new markers for determining adequate glycemic control.
Subject(s)
Arthritis, Infectious/etiology , Glycated Hemoglobin/analysis , Hyperglycemia/complications , Prosthesis-Related Infections/etiology , Surgical Wound Infection/etiology , Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Knee/adverse effects , Biomarkers , Blood Glucose/analysis , Humans , Odds Ratio , Perioperative PeriodABSTRACT
BACKGROUND: While the preferred surgical treatment for chronic periprosthetic joint infection (PJI) in North America is a 2-stage exchange arthroplasty, the optimal time between first-stage and reimplantation surgery remains unknown. This study was conceived to examine the association between time to reimplantation and treatment failure. METHODS: Using an institutional database, we identified PJI cases treated with 2-stage exchange arthroplasty between 2000 and 2016. Musculoskeletal Infection Society criteria were used to define PJI, and treatment failure was defined using Delphi criteria. The interstage interval between first-stage and reimplantation surgery for each case was collected, alongside demographics, patient-related and organism-specific data. Multivariate logistic regression analyses were used to examine association with treatment failure. RESULTS: Our final analysis consisted of 282 patients with an average time to reimplantation of 100.2 days (range, 20-648). Sixty-three patients (22.3%) failed at 1 year based on Delphi criteria. Time to reimplantation was not significantly associated with failure in both univariate (P = .598) and multivariate (P = .397) models. However, patients reimplanted at >26 weeks were twice as likely to fail in comparison to those reimplanted within <26 weeks (43.8% vs 21.1%), and this finding reached marginal significance (P = .057). Patients who failed had significantly more comorbidities (P = .008). Charlson comorbidity index was the only variable significantly associated with treatment failure in regression analysis (odds ratio, 1.40; 95% confidence interval, 1.06-1.86; P = .019). CONCLUSION: The length of the interstage interval was not a statistically significant predictor of failure in patients undergoing 2-stage exchange arthroplasty for PJI.
Subject(s)
Arthritis, Infectious/surgery , Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Knee/adverse effects , Prosthesis-Related Infections/surgery , Aged , Databases, Factual , Female , Humans , Male , Middle Aged , North America , Odds Ratio , Reoperation , Retrospective Studies , Time Factors , Treatment FailureABSTRACT
BACKGROUND: The introduction of the Musculoskeletal Infection Society (MSIS) criteria for periprosthetic joint infection (PJI) in 2011 resulted in improvements in diagnostic confidence and research collaboration. The emergence of new diagnostic tests and the lessons we have learned from the past 7 years using the MSIS definition, prompted us to develop an evidence-based and validated updated version of the criteria. METHODS: This multi-institutional study of patients undergoing revision total joint arthroplasty was conducted at 3 academic centers. For the development of the new diagnostic criteria, PJI and aseptic patient cohorts were stringently defined: PJI cases were defined using only major criteria from the MSIS definition (n = 684) and aseptic cases underwent one-stage revision for a noninfective indication and did not fail within 2 years (n = 820). Serum C-reactive protein (CRP), D-dimer, erythrocyte sedimentation rate were investigated, as well as synovial white blood cell count, polymorphonuclear percentage, leukocyte esterase, alpha-defensin, and synovial CRP. Intraoperative findings included frozen section, presence of purulence, and isolation of a pathogen by culture. A stepwise approach using random forest analysis and multivariate regression was used to generate relative weights for each diagnostic marker. Preoperative and intraoperative definitions were created based on beta coefficients. The new definition was then validated on an external cohort of 222 patients with PJI who subsequently failed with reinfection and 200 aseptic patients. The performance of the new criteria was compared to the established MSIS and the prior International Consensus Meeting definitions. RESULTS: Two positive cultures or the presence of a sinus tract were considered as major criteria and diagnostic of PJI. The calculated weights of an elevated serum CRP (>1 mg/dL), D-dimer (>860 ng/mL), and erythrocyte sedimentation rate (>30 mm/h) were 2, 2, and 1 points, respectively. Furthermore, elevated synovial fluid white blood cell count (>3000 cells/µL), alpha-defensin (signal-to-cutoff ratio >1), leukocyte esterase (++), polymorphonuclear percentage (>80%), and synovial CRP (>6.9 mg/L) received 3, 3, 3, 2, and 1 points, respectively. Patients with an aggregate score of greater than or equal to 6 were considered infected, while a score between 2 and 5 required the inclusion of intraoperative findings for confirming or refuting the diagnosis. Intraoperative findings of positive histology, purulence, and single positive culture were assigned 3, 3, and 2 points, respectively. Combined with the preoperative score, a total of greater than or equal to 6 was considered infected, a score between 4 and 5 was inconclusive, and a score of 3 or less was not infected. The new criteria demonstrated a higher sensitivity of 97.7% compared to the MSIS (79.3%) and International Consensus Meeting definition (86.9%), with a similar specificity of 99.5%. CONCLUSION: This study offers an evidence-based definition for diagnosing hip and knee PJI, which has shown excellent performance on formal external validation.
Subject(s)
Arthritis, Infectious/diagnosis , Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Knee/adverse effects , Prosthesis-Related Infections/diagnosis , Reoperation/statistics & numerical data , Synovial Fluid/chemistry , Aged , Area Under Curve , Arthritis, Infectious/etiology , Blood Sedimentation , C-Reactive Protein/analysis , Carboxylic Ester Hydrolases , Diagnostic Tests, Routine , Evidence-Based Medicine , Female , Fibrin Fibrinogen Degradation Products/analysis , Frozen Sections , Humans , Inflammation/surgery , Knee Joint/surgery , Leukocyte Count , Male , Middle Aged , Prosthesis-Related Infections/etiology , Sensitivity and Specificity , Young AdultABSTRACT
In the modern operating room (OR), traditional surgical mask, frequent air exchanges, and architectural barriers are viewed as effective in reducing airborne microbial populations. Intraoperative sampling of airborne particulates is rarely performed in the OR because of technical difficulties associated with sampling methodologies and a common belief that airborne contamination is infrequently associated with surgical site infections (SSIs). Recent studies suggest that viable airborne particulates are readily disseminated throughout the OR, placing patients at risk for postoperative SSI. In 2017, virtually all surgical disciplines are engaged in the implantation of selective biomedical devices, and these implants have been documented to be at high risk for intraoperative contamination. Approximately 1.2 million arthroplasties are performed annually in the United States, and that number is expected to increase to 3.8 million by the year 2030. The incidence of periprosthetic joint infection is perceived to be low (<2.5%); however, the personal and fiscal morbidity is significant. Although the pharmaceutic and computer industries enforce stringent air quality standards on their manufacturing processes, there is currently no U.S. standard for acceptable air quality within the OR environment. This review documents the contribution of air contamination to the etiology of periprosthetic joint infection, and evidence for selective innovative strategies to reduce the risk of intraoperative microbial aerosols.