Tranexamic Acid Is Associated With Reduced Periprosthetic Joint Infection After Primary Total Joint Arthroplasty

BackgroundPrevious studies have demonstrated preoperative anemia to be a strong risk factor for periprosthetic joint infection (PJI) in total joint arthroplasty (TJA). Allogeneic blood transfusion can be associated with increased risk of PJI after primary and revision TJA. Tranexamic acid (TXA) is known to reduce blood loss and the need for allogeneic blood transfusion after TJA. The hypothesis of this study is that administration of intravenous TXA would result in a reduction in PJI after TJA.MethodsAn institutional database was utilized to identify 6340 patients undergoing primary TJA between January 1, 2013 and June 31, 2017 with a minimum of 1-year follow-up. Patients were divided into 2 groups based on whether they received intravenous TXA prior to TJA or not. Patients who developed PJI were identified. All PJI patients met the 2018 International Consensus Meeting definition for PJI. A multivariate regression analysis was performed to identify variables independently associated with PJI.ResultsOf the patients included, 3683 (58.1%) received TXA and 2657 (41.9%) did not. The overall incidence of preoperative anemia was 16%, postoperative blood transfusion 1.8%, and PJI 2.4%. Bivariate analysis showed that patients who received TXA were significantly at lower odds of infection. After adjusting for all confounding variables, multivariate regression analysis showed that TXA is associated with reduced PJI after primary TJA.ConclusionTXA can help reduce the rate of PJI after primary TJA. This protective effect is likely interlinked to reduction in blood loss, lower need for allogeneic blood transfusion, and issues related to immunomodulation associated with blood transfusion.     

The Cost-Effectiveness of Silver-Impregnated Occlusive Dressings for Infection Prevention After Total Joint Arthroplasty

BackgroundProsthetic joint infection (PJI) is a catastrophic complication after total joint arthroplasty that exacts a substantial economic burden on the health-care system. This study used break-even analysis to investigate whether the use of silver-impregnated occlusive dressings is a cost-effective measure for preventing PJI after primary total knee arthroplasty (TKA) and total hip arthroplasty (THA).MethodsBaseline infection rates after TKA and THA, the cost of revision arthroplasty for PJI, and the cost of a silver-impregnated occlusive dressing were determined based on institutional data and the existing literature. A break-even analysis was then conducted to calculate the minimal absolute risk reduction needed for cost-effectiveness.ResultsThe use of silver-impregnated occlusive dressings would be economically viable at an infection rate of 1.10%, treatment costs of $25,692 for TKA PJI, and $31,753 for THA PJI and our institutional dressing price of $38.05 if it reduces infection rates after TKA by 0.15% (the number needed to treat [NNT] = 676) and THA by 0.12% (NNT = 835). The absolute risk reduction needed to maintain cost-effectiveness did not change with varying initial infection rates and remained less than 0.40% (NNT = 263) for infection treatment costs as low as $10,000 and less than 0.80% (NNT = 129) for dressing prices as high as $200.ConclusionThe use of silver-impregnated occlusive dressings is a cost-effective measure for infection prophylaxis after TKA and THA.     

Visceral Fat as a Risk Factor for Periprosthetic Joint Infection After Total Hip and Knee Arthroplasty

BackgroundVisceral obesity, a strong indicator of chronic inflammation and impaired metabolic health, has been shown to be associated with poor postoperative outcomes and complications. This study aimed to evaluate the relationship between visceral fat area (VFA) and periprosthetic joint infection (PJI) in total joint arthroplasty (TJA) patients.MethodsA retrospective study of 484 patients who had undergone a total hip or knee arthroplasty was performed. All patients had a computed tomography scan of the abdomen/pelvis within two years of their TJA. Body composition data (ie, VFA, subcutaneous fat area, and skeletal muscle area) were calculated at the Lumbar-3 vertebral level via two fully automated and externally validated machine learning algorithms. A multivariable logistic model was created to determine the relationship between VFA and PJI, while accounting for other PJI risk factors. Of the 484 patients, 31 (6.4%) had a PJI complication.ResultsThe rate of PJI among patients with VFA in the top quartile (> 264.1 cm²) versus bottom quartile (< 82.6 cm²) was 5.6% versus 10.6% and 18.8% versus 2.7% in the total hip arthroplasty and total knee arthroplasty cohorts, respectively. In the multivariate model, total knee arthroplasty patients with a VFA in the top quartile had a 30.5 times greater risk of PJI than those in the bottom quartile of VFA (P = .0154).ConclusionVFA may have a strong association with PJI in TJA patients. Using a standardized imaging modality like computed tomography scans to calculate VFA can be a valuable tool for surgeons when assessing risk of PJI.     

Tobacco Use and Risk of Wound Complications and Periprosthetic Joint Infection: A Systematic Review and Meta-Analysis of Primary Total Joint Arthroplasty Procedures

Background

The purpose of this study was to perform a systematic review and meta-analysis to quantitatively assess the association between tobacco use and the risk of any wound complication and periprosthetic joint infection (PJI) after primary total hip and total knee arthroplasty procedures.

Aseptic Reoperations Within 1 Year of Primary Total Knee Arthroplasty Markedly Increase the Risk of Later Periprosthetic Joint Infection

BackgroundDespite the high rate of success of primary total knee arthroplasty (TKA), some patients are candidates for early aseptic reoperation. The goal of this study is to evaluate the risk of subsequent periprosthetic joint infection (PJI) in patients treated with an aseptic reoperation within 1 year of primary TKA.MethodsA retrospective review of our total joint registry compared 249 primary TKAs requiring an aseptic reoperation within 1 year following index arthroplasty to a control group of 17,867 TKAs not requiring reoperation within 1 year. Patients were divided into groups based on time from index TKA: (1) 90 days or less (114 TKAs) and (2) 91 to 365 days (135 TKAs). Mean age was 68 years with 57% female. Mean follow-up was 7 years.ResultsAt 2 years postoperatively, patients undergoing an aseptic reoperation within 90 days subsequently had a 9% PJI rate, while patients undergoing an aseptic reoperation between 91 and 365 days subsequently had a 3% PJI rate. The control group had a 0.4% PJI rate. Compared to the control group, patients undergoing an aseptic reoperation within 90 days had an elevated risk of PJI (hazard ratio, 9; P < .0001), as did patients who had a reoperation between 91 and 365 days (hazard ratio, 4; P < .0001).ConclusionAseptic reoperation within 1 year of primary TKA was associated with a notably increased risk of subsequent PJI.     

Statin Exposure and Risk of Prosthetic Joint Infection After Total Knee or Hip Arthroplasty Among U.S. Veterans

BackgroundStatins have a variety of pleiotropic effects that could be beneficial for patients undertaking total knee or hip arthroplasty. In vitro and in vivo models suggest the beneficial effects of statins through bone formation and modulating proinflammatory cytokines triggered by implant debris. However, statins also exhibit antimicrobial action and may reduce the risk of revision surgery via reducing the risk of infection. We sought to explore the relationship between statin use and prosthetic joint infection (PJI) after total knee or hip arthroplasty.MethodsWe use a retrospective cohort of patients undergoing total knee or hip arthroplasty performed within the Department of Veterans Affairs. To minimize selection bias between the statin exposed and unexposed patients, we used 1:1 ratio propensity score matching. We fit adjusted Cox proportional hazards models to quantify the risk of PJI between the cohorts within 1 year, 3 years, and all follow-up time.ResultsWith a study period beginning from January 2000, a total of 60,241 patients were included. The unmatched Cox models reveal, over the entire follow-up time, a statistically significant lower risk of infection for the statin exposed patients (hazard ratio = 0.869; 95% confidence interval = [0.79-0.956]). The matched Cox model results reveal a statistically significant lower risk of PJI, only in the overall model, for the statin exposed cohort compared with the unexposed cohort (hazard ratio = 0.895, 95% confidence interval = [0.807-0.993]).ConclusionOur analysis finds some support for the beneficial effects of statins for preventing PJI among patients undergoing total knee or hip arthroplasty.     

Preoperative Risk Factor Screening Protocols in Total Joint Arthroplasty: A Systematic Review

BackgroundPreoperative optimization protocols targeting potentially modifiable risk factors could prove beneficial in reducing the rate of complications in lower extremity total joint arthroplasty (LE-TJA). We aimed to summarize the evidence on preoperative screening protocols targeting modifiable risk factors to assess their effect on postoperative outcomes following primary LE-TJA.MethodsA literature search of MEDLINE, EMBASE, CINAHL, and Cochrane Library databases was performed in August 2019. The bibliographies of relevant publications were searched for further applicable studies. Included studies were required to report at least one outcome including prosthetic joint infection/surgical site infection (PJI/SSI), hospital length of stay (LOS), disposition, 90-day emergency department visits, or hospital readmissions after implementation of an evidence-based preoperative optimization protocol targeting modifiable risk factors. Methodological quality of included studies was assessed using the methodological index for non-randomized studies (MINORS) criteria.ResultsA total of 8 retrospective cohort studies including 9915 patients were reviewed. Implementation of preoperative optimization protocols were associated with reductions in SSI (0.56% vs. 2.60%; RR 0.21 [95% CI 0.12 to 0.37]; P < .00001), hospital LOS, mean cost of care, and hospital readmission rates. The mean MINORS score for comparative studies was 16.285.ConclusionsImplementation and compliance with evidence-based preoperative protocols for optimization of modifiable risk factors is associated with overall improved outcomes following LE-TJA. SSI, hospital LOS, average total cost of care, and hospital readmission rates were favorable in those cohorts subjected to a preoperative intervention protocol. Future prospective studies are necessary for further refinement of preoperative optimization protocols and referral algorithms, without compromising patients’ access to surgery.Level of EvidenceIII, Systematic Review;     

Risk of Periprosthetic Joint Infection After Intra-Articular Corticosteroid Injection Following Unicompartmental Knee Arthroplasty

BackgroundPerioperative intra-articular joint injection is a known risk factor for developing prosthetic joint infection (PJI) in the immediate preoperative and postoperative periods for total knee arthroplasty, but is less defined in unicompartmental knee arthroplasty (UKA). The goal of this study was to elucidate the risk of developing PJI after intra-articular corticosteroid injection (IACI) into a post UKA knee.MethodsA retrospective review of a nationwide administrative claims database was performed from January 2015 to October 2020. Patients who underwent UKA and had an ipsilateral IACI were identified and matched 2:1 to a control group of primary UKA patients who did not receive IACI. Multivariate logistic analyses were conducted to assess differences in PJI rates at 6 months, 1 year, and 2 years.ResultsA total of 47,903 cases were identified, of which 2,656 (5.5%) cases received IACI. The mean time from UKA to IACI was 355 days. The incidence of PJI in the IACI group was 2.7%, compared to 1.3% in the control group. The rate of PJI after IACI was significantly higher than the rate in the control group at 6 months, 1 year, and 2 years (all P < .05). The majority of PJI occurred within the first 6 months following IACI (75%).ConclusionIn this study, IACI in a UKA doubled the risk of PJI compared to patients who did not receive an injection. Surgeons should be aware of this increased risk to aid in their decision-making about injecting into a UKA.Level of EvidenceIII, retrospective comparative study.     

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.     

Low-Dose Aspirin for Venous Thromboembolism Prophylaxis is Associated With Lower Rates of Periprosthetic Joint Infection After Total Joint Arthroplasty

BackgroundAspirin as a venous thromboembolism (VTE) prophylactic agent has been shown to have antistaphylococcal and antibiofilm roles. Optimal acetylsalicylic acid (ASA) dosage would facilitate antimicrobial effects while avoiding over-aggressive inhibition of platelet antimicrobial function. Our purpose was to determine the periprosthetic joint infection (PJI) rate after total joint arthroplasty in patients receiving low-dose ASA (81 mg twice a day), in comparison to high-dose ASA (325 mg twice a day).MethodsWe conducted a retrospective cohort study between 2008 and 2020. Eligible patients were older than 18 years, underwent primary total joint arthroplasty, both total knee arthroplasty and total hip arthroplasty, had a minimum 30-day follow-up, and received a full course ASA as VTE prophylaxis. Patients’ records were reviewed for PJI, according to Musculoskeletal Infection Society criteria. Patients were excluded if they underwent revision arthroplasty, had a history of coagulopathy, or had an ASA regimen that was not completed. In total 15,825 patients were identified, 8,761 patients received low-dose ASA and 7,064 received high-dose ASA.ResultsThe high-dose cohort had a higher PJI rate (0.35 versus 0.10%, P = .001). This relationship was maintained when comparing subgroups comprising total knee arthroplasty (0.32 versus 0.06%, P = .019) or total hip arthroplasty (0.38 versus 0.14%, P = .035) and accounting for potentially confounding demographic and surgical variables (odds ratio = 2.59, 95% CI = 1.15-6.40, P = .028).ConclusionComparing low-dose to high-dose ASA as a VTE prophylactic agent, low-dose ASA had a lower PJI rate. This may be attributable to a balance of anti-infective properties of ASA and antiplatelet effects.     

Socioeconomic Status May Not Be a Risk Factor for Periprosthetic Joint Infection

BackgroundPeriprosthetic joint infection (PJI) is a devastating complication after total joint arthroplasty, carrying significant economic and personal burden. The goal of this study is to use an established database to analyze socioeconomic variables and assess their relationship to PJI. Additionally, we sought to evaluate whether socioeconomic factors, along with other known risk factors of PJI, when controlled for in a statistical model affected the familial risk of PJI.MethodsWith approval from our Institutional Review Board we performed a population-based retrospective cohort study on all primary total joint arthroplasty cases of the hip or knee (n = 85,332), within a statewide database, between January 1996 and December 2013. We excluded 9854 patients due to age <18 years, missing data, history of PJI prior to index procedure, and no evidence of 2-year follow-up (excluding those with PJI). Cases that developed PJI following the index procedure (n = 2282) were compared to those that did not (n = 73,196).ResultsAfter adjusting for covariates, patients with Medicaid as a primary payer were at greater risk for experiencing PJI (relative risk 1.40, 95% confidence interval [CI] 1.08-1.82, P = .01). There was no difference in risk between the groups associated with education level or median household income (all, P > .05). First-degree relatives of patients who develop PJI (hazard ratio 1.66, 95% CI 1.23-2.24, P = .001) and first-degree and second-degree relatives combined (hazard ratio 1.39, 95% CI 1.09-1.77, P = .007) were at greater risk despite controlling for the above socioeconomic factors.ConclusionOur study provides further support that genetic factors may underlie PJI as we did observe significant familial risk even after accounting for socioeconomic factors and payer status. We did not find a correlation between education level or household income and PJI; however, Medicaid payees were at increased risk. Continued study is needed to define a possible heritable disposition to PJI in an effort to optimize treatment and possibly prevent this complication.     

Risk Factors for Periprosthetic Joint Infection Following Primary Total Hip Arthroplasty: A Case Control Study

The purpose of this study was to identify the specific comorbidities and demographic factors that are independently associated with an increased risk of periprosthetic joint infection (PJI) in total hip arthroplasty (THA) patients. A case–control study design was used to compare 88 patients who underwent unilateral primary THA and developed PJI with 499 unilateral primary THA patients who did not develop PJI. The impact of 18 comorbid conditions and other demographic factors on PJI was examined. Depression, obesity, cardiac arrhythmia, and male gender were found to be independently associated with an increased risk of PJI in THA patients. This information is important to consider when counseling patients on the risks associated with elective THA, and for risk-adjusting publicly reported THA outcomes.     

Risk of Periprosthetic Infection Following Intra-Articular Corticosteroid Injections After Total Knee Arthroplasty

BackgroundRecent literature has advocated for the effectiveness of postoperative steroid injections following total knee arthroplasty (TKA) for improving pain and range of motion when other correctible causes of these symptoms have been eliminated. The safety of such injections has not been thoroughly evaluated. The aim of this study was to determine the risk of acute infection following intra-articular corticosteroid injection into a preexisting TKA.MethodsThe Humana dataset was used to identify patients who underwent TKA from 2007 to 2017. Patients with ipsilateral knee corticosteroid injections in the postoperative period were then identified and compared to a 2:1 matched control cohort. A diagnosis of infection within 6 months and 1 year following the injection and an ipsilateral procedure for infection at any time postoperatively were then assessed and compared to controls using a multivariate binomial logistic regression analysis.ResultsOf the 166,946 TKA performed during the study period, 5628 patients had a postoperative corticosteroid injection (3.4%). Patients with injections had a significantly higher rate of periprosthetic infection compared to noninjection matched controls at all studied time points.ConclusionIn a large national database, about 3% of patients who undergo TKA have a postoperative steroid injection into their postoperative knee. While there is some existing literature demonstrating improvement in pain and stiffness symptoms after TKA with postoperative injections, the present study demonstrates a significant correlation between postoperative intra-articular corticosteroid injections in patients with preexisting TKA and periprosthetic joint infection compared to matched controls who did not receive an injection.     

Mortality During Total Knee Periprosthetic Joint Infection

Background

Periprosthetic joint infections (PJIs) are fraught with multiple complications including poor patient-reported outcomes, disability, reinfection, disarticulation, and even death. We sought to perform a systematic review asking the question: (1) What is the mortality rate of a PJI of the knee undergoing 2-stage revision for infection? (2) Has this rate improved over time? (3) How does this compare to a normal cohort of individuals?

1.5-Stage Exchange Arthroplasty for Total Knee Arthroplasty Periprosthetic Joint Infections

BackgroundPeriprosthetic joint infection (PJI) in total knee arthroplasty (TKA) is a challenging problem. The purpose of this study was to outline a novel technique to treat TKA PJI. We define 1.5-stage exchange arthroplasty as placing an articulating spacer with the intent to last for a prolonged time.MethodsA retrospective review was performed from 2007 to 2019 to evaluate patients treated with 1.5-stage exchange arthroplasty for TKA PJI. Inclusion criteria included: articulating knee spacer(s) remaining in situ for 12 months and the patient deferring a second-stage reimplantation because the patient had acceptable function with the spacer (28 knees) or not being a surgical candidate (three knees). Thirty-one knees were included with a mean age of 63 years, mean BMI 34.4 kg/m², 12 were female, with a mean clinical follow-up of 2.7 years. Cobalt-chrome femoral and polyethylene tibial components were used. We evaluated progression to second-stage reimplantation, reinfection, and radiographic outcomes.ResultsAt a mean follow-up of 2.7 years, 25 initial spacers were in situ (81%). Five knees retained their spacer(s) for some time (mean 1.5 years) and then underwent a second-stage reimplantation; one of the five had progressive radiolucent lines but no evidence of component migration. Three knees (10%) had PJI reoccurrence. Four had progressive radiolucent lines, but there was no evidence of component migration in any knees.Conclusions1.5-stage exchange arthroplasty may be a reasonable method to treat TKA PJI. At a mean follow-up of 2.7 years, there was an acceptable rate of infection recurrence and implant durability.     

Sarcopenia as a Risk Factor for Prosthetic Infection After Total Hip or Knee Arthroplasty

Background

Sarcopenia, an age-related loss of muscle mass and function, has been previously linked to an increased risk of morbidity, mortality, and infection after a variety of surgical procedures. This study is the first to evaluate the impact of the psoas-lumbar vertebral index (PLVI), a validated marker for central sarcopenia, on determining post-arthroplasty infection status.

Greater Knee Soft Tissue Thickness Predisposes Patients to Subsequent Periprosthetic Joint Infection After Total Knee Arthroplasty

BackgroundAlthough 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.MethodsA 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.ResultsIncreased 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.ConclusionAnterior 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.     

Topical Vancomycin Powder and Dilute Povidone-Iodine Lavage Reduce the Rate of Early Periprosthetic Joint Infection After Primary Total Knee Arthroplasty

BackgroundVancomycin powder and dilute povidone-iodine lavage (VIP) was introduced to reduce the incidence of periprosthetic joint infection (PJI) in high-risk total knee arthroplasty (TKA) patients. We hypothesize that VIP can reduce the incidence of early PJI in all primary TKA patients, regardless of preoperative risk.MethodsAn infection database of primary TKAs performed before a VIP protocol was implemented (January 2012-December 2013), during a time when only high-risk TKAs received VIP (January 2014-December 2015), and when all TKAs received VIP (January 2016-September 2019) at an urban, university-affiliated, not-for-profit orthopedic hospital was retrospectively reviewed to identify patients with PJI. Criteria used for diagnosis of PJI were the National Healthcare Safety Network and Musculoskeletal Infection Society guidelines.ResultsVIP reduced early primary TKA PJI incidence in both the high-risk and all-risk cohorts compared with the pre-VIP cohort by 44.6% and 56.4%, respectively (1.01% vs 0.56% vs 0.44%, P = .0088). In addition, after introducing VIP to all-risk TKA patients, compared with high-risk TKA patients, the relative risk of PJI dropped an additional 21.4%, but this finding did not reach statistical significance (0.56% vs 0.44%, P = .4212). There were no demographic differences between the 3 VIP PJI cohorts.ConclusionVIP is associated with a reduced early PJI incidence after primary TKA, regardless of preoperative risk. With the literature supporting its safety and cost-effectiveness, VIP is a value-based intervention, but given the nature of this historical cohort study, a multicenter randomized controlled trial is underway to definitively confirm its efficacy.