Does Symptomatic Benign Prostatic Hyperplasia Increase the Risk of Periprosthetic Joint Infection After Primary Total Joint Arthroplasty?

BackgroundPeriprosthetic joint infection (PJI) is among the leading causes of failure in total joint arthroplasty. A recently proposed risk factor for PJI is symptomatic benign prostatic hyperplasia (sBPH). This study aims to determine if sBPH is associated with PJI following primary total hip arthroplasty (THA) and total knee arthroplasty (TKA).MethodsUsing the Mariner all-payer claims database, 1745 patients with sBPH undergoing primary THA were propensity-matched with 3490 controls, and 3053 patients with sBPH undergoing primary TKA were propensity-matched with 6106 controls. Additionally, the same 1745 patients with sBPH undergoing THA were compared to 317,360 prematched controls, and the same 3053 patients with sBPH undergoing TKA were compared to 557,730 prematched controls. Univariate analysis was conducted using chi-squared or ANOVA where appropriate.ResultsAt two years postoperatively, patients with sBPH were not at significantly increased risk for PJI following primary THA (1.54% vs 1.43%; P = .745) and TKA (1.99% vs 2.14%; P = .642) relative to postmatch controls. Compared to matched controls, THA patients with sBPH had an increased 90-day incidence of anemia (P < .001), blood transfusion (P < .001), and urinary tract infection (UTI; P < .001). Total knee arthroplasty patients with sBPH had an increased 90-day incidence of anemia (P < .001), blood transfusion (P < .001), cellulitis (P = .023), renal failure (P = .030), heart failure (P = .029), and UTI (P < .001) relative to matched controls.ConclusionIn primary THA and TKA, sBPH does not appear to be an independent risk factor for PJI within two years postoperatively. However, clinicians should be cognizant of the significantly increased risk for postoperative UTI in this patient population.     

Preoperative Corticosteroid Injections Demonstrate a Temporal and Dose-Dependent Relationship with the Rate of Postoperative Infection Following Total Hip Arthroplasty

BackgroundCorticosteroid injections (CSI) are commonly used for the treatment of osteoarthritis of the hip. There is concern, however, that these injections may increase the risk of postoperative infection if a subsequent total hip arthroplasty (THA) is performed. The purpose of the present investigation is to determine the relationship between CSI and the risk of periprosthetic joint infection (PJI) and surgical site infections (SSIs) following THA.MethodsThe PearlDiver database was reviewed for patients undergoing THA from 2011 to 2018. Patients with unilateral hip osteoarthritis who received an intra-articular hip CSI prior to ipsilateral THA were matched in a sequential 1:1 fashion based on age, gender, and Charlson Comorbidity Index with THA patients who did not receive an injection in the preoperative period. PJI and SSI within 6 months of the surgical procedure were recorded. Statistical analysis included chi-squared test and multivariate logistic regression. Results were considered significant at P < .05.ResultsIn total, 29,058 patients underwent a hip CSI within 6 months prior to THA. CSI within 4 months of surgery was associated with a higher incidence of PJI at 6-month follow up (1.6% vs 1.1%, P = .040). An injection within 1 month of surgery corresponded to a higher odds of PJI (odds ratio [OR] 1.97) than an injection 4 months prior to surgery (OR 1.24). Furthermore, the quantity of CSI administered within the 3 months prior to THA demonstrated a dose-dependent relationship, with each subsequent injection increasing odds of PJI (OR 1.45-3.59). A similar relationship was observed for SSI.ConclusionThere appears to be both a time and dose-dependent association of hip CSI and PJI following THA. Surgeons should consider delaying elective THA if a CSI has been administered within the 4 months prior to the planned procedure.     

No Difference in the Rate of Periprosthetic Joint Infection in Patients Undergoing the Posterolateral Compared to the Direct Anterior Approach

BackgroundThere remains inconsistent data about the association of surgical approach and periprosthetic joint infection (PJI). We sought to evaluate the risk of reoperation for superficial infection and PJI after primary total hip arthroplasty (THA) in a multivariate model.MethodsWe reviewed 16,500 primary THAs, collecting data on surgical approach and all reoperations within 1 year for superficial infection (n = 36) or PJI (n = 70). Considering superficial infection and PJI separately, we used Kaplan–Meier survivorship to assess survival free from reoperation and a Cox Proportional Hazards multivariate models to assess risk factors for reoperation.ResultsBetween direct anterior approach (DAA) (N = 3,351) and PLA (N = 13,149) cohorts, rates of superficial infection (0.4 versus 0.2%) and PJI (0.3 versus 0.5%) were low and survivorship free from reoperation for superficial infection (99.6 versus 99.8%) and PJI (99.4 versus 99.7%) were excellent at both 1 and 2 years. The risk of developing superficial infection increased with high body mass index (BMI) (hazard ratio [HR] = 1.1 per unit increase, P = .003), DAA (HR = 2.7, P = .01), and smoking status (HR = 2.9, P = .03). The risk of developing PJI increased with the high BMI (HR = 1.04, P = .03), but not surgical approach (HR = 0.68, P = .3).ConclusionIn this study of 16,500 primary THAs, DAA was independently associated with an elevated risk of superficial infection reoperation compared to the PLA, but there was no association between surgical approach and PJI. An elevated patient BMI was the strongest risk factor for superficial infection and PJI in our cohort.Level of EvidenceIII, retrospective cohort study.     

Infection Risk Increases After Total Hip Arthroplasty Within 3 Months Following Intra-Articular Corticosteroid Injection. A Meta-Analysis on Knee and Hip Arthroplasty

BackgroundMuch debate continues regarding the risk of postoperative infection after intra-articular corticosteroid injection prior to total joint arthroplasty. The aim of this study was to evaluate the risk of periprosthetic joint infection (PJI) or other complications after joint arthroplasty in patients who received preoperative corticosteroids injections.MethodsA literature search was performed on PubMed, Web of Science, and Cochrane Library through January 4, 2022. Of 4,596 studies, 28 studies on 480,532 patients were selected for qualitative analysis. Studies describing patients receiving corticosteroids injections before joint arthroplasty (hip, knee) were included in the systematic review. A meta-analysis was performed of studies focusing on corticosteroids injections and PJI. Assessment of risk of bias and quality of evidence was based on the “Downs and Black’s Checklist for Measuring Quality”.ResultsA significant association (odds ratio: 1.55, P = .001, 95% confidence interval: 1.357-1.772) between PJI and corticosteroids injections was found for total hip arthroplasty (THA). No association was found for knee arthroplasty procedures. The risk of PJI is statistically higher (odds ratio: 1.20, P = .045, 95% confidence interval: 1.058-1.347) if the injections are performed within 3 months preoperatively in THA patients.ConclusionPatients undergoing THA who previously received intra-articular injections of corticosteroids may expect a statistically higher risk of developing PJI. On the contrary, no association between corticosteroids injections and PJI could be seen in total knee arthroplasty patients. In addition, injection timing plays an important role: surgeons should refrain from administering corticosteroids injections within 3 months before hip arthroplasty, as it appears to be less safe than waiting a 3-month interval.     

Cement Loaded With High-Dose Gentamicin and Clindamycin Reduces the Risk of Subsequent Infection After One-Stage Hip or Knee Arthroplasty Exchange for Periprosthetic Infection: A Preliminary Study

BackgroundThe use of antibiotic-loaded acrylic cement for treating periprosthetic joint infections remains controversial. We hypothesized that the raw rate of surgical site infection (SSI) is lower after using cement loaded with high-dose gentamicin and clindamycin than after using cement loaded with standard-dose gentamicin for implant fixation during 1-stage hip and knee revision arthroplasty for infection.MethodsOne hundred seventy-one continuous patients operated by 2 experienced surgeons during a 2-year period were included in the study. All patients were followed for 24 months. The primary endpoint was the raw rate of SSI after 2 years of follow-up time.ResultsThe raw rate of SSI after 2 years of follow-up time was significantly lower in the study group (13%) than in the control group (26%) (P = .03) with an odds ratio of 0.42 (P = .03). These SSIs were new infections rather than a recurrence/persistence of the initial infection.ConclusionThe cement used in the study group significantly reduced the risk of SSI relative to the cement used in the control group. Routine use of this high-dose dual antibiotic-loaded cement can be considered during 1-stage knee or hip revision arthroplasty for infection.     

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.     

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.     

Comparison of the Efficacy Between Closed Incisional Negative-Pressure Wound Therapy and Conventional Wound Management After Total Hip and Knee Arthroplasties: A Systematic Review and Meta-Analysis

BackgroundWound-related problems after total hip arthroplasty (THA) and total knee arthroplasty (TKA) can cause periprosthetic joint infections. We sought to evaluate the effect of closed incisional negative-pressure wound therapy (ciNPWT) on wound complications, skin blisters, surgical site infections (SSIs), reoperations, and length of hospitalization (LOH).MethodsStudies comparing ciNPWT with conventional dressings following THA and TKA were systematically searched on MEDLINE, Embase, and the Cochrane Library. Two reviewers performed the study selection, risk of bias assessment, and data extraction. Funnel plots were employed to evaluate publication bias and forest plots to analyze pooled data.ResultsTwelve studies were included herein. The odds ratios (ORs) for wound complications and SSIs indicated a lack of publication bias. ciNPWT showed significantly lower risks of wound complication (OR, 0.44; 95% confidence interval [CI], 0.22-0.9; P = .027) and SSI (OR, 0.39; 95% CI, 0.23-0.68; P < .001) than did conventional dressings. ciNPWT also yielded a significantly lower reoperation rate (OR, 0.38; 95% CI, 0.21-0.69; P = .001) and shorter LOH (mean difference, 0.41 days; 95% CI, −0.51 to −0.32; P < .001). However, the rate of skin blisters was higher in ciNPWT (OR, 4.44; 95% CI, 2.24-8.79; P < .001).ConclusionAlthough skin blisters were more likely to develop in ciNPWT, the risks of wound complication, SSI, reoperation, and longer LOH decreased in ciNPWT compared with those in conventional dressings. This finding could alleviate the potential concerns regarding wound-related problems after THA and TKA.     

Trends of Prosthetic Joint Infection Organisms and Recurrence for a Single High-Volume Arthroplasty Surgeon Over 20 Years

BackgroundProsthetic joint infection (PJI) is a morbid complication following total joint arthroplasty (TJA). PJI diagnosis and treatment has changed over time, and patient co-management with a high-volume musculoskeletal infectious disease (MSK ID) specialist has been implemented at our institution in the last decade.MethodsWe retrospectively evaluated all consecutive TJA patients treated for PJI between 1995 and 2018 by a single high-volume revision TJA surgeon. Microbial identities, antibiotic resistance, prior PJI, and MSK ID consultation were investigated.ResultsIn total, 261 PJI patients (median age 66 years, interquartile range 57-75) were treated. One-year and 5-year reinfection rates were 15.8% (95% confidence interval [CI] 11.6-20.7) and 22.1% (95% CI 17.0-27.7), respectively. Microbial identities and antibiotic resistances did not change significantly over time. Despite seeing more prior PJI patients (53.3% vs 37.6%, P = .012), MSK ID-managed patients had similar infection rates as non-MSK ID-managed patients (hazard ratio [HR] 1.02, 95% CI 0.6-1.75, P = .93). Prior PJI was associated with higher reinfection risk (HR 2.39, 95% CI 1.39-4.12, P = .002) overall and in patients without MSK ID consultation, specifically (HR 2.78, 95% CI 1.37-5.65, P = .005). This risk was somewhat lower and did not reach significance in prior PJI patients with MSK ID consultation (HR 1.97, 95% CI 0.87-4.48, P = .106).ConclusionWe noted minimal differences in microbial/antibiotic resistances for PJI over 20 years in a single institution, suggesting current standards of PJI treatment remain encouragingly valid in most cases. MSK ID involvement was not associated with lower reinfection risk overall; however, in patients with prior PJI, the risk of reinfection appeared to be somewhat lower with MSK ID involvement.Level of EvidenceLevel IV–Case Series.     

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.     

Hypoalbuminemia Predicts Failure of Two-Stage Exchange for Chronic Periprosthetic Joint Infection of the Hip and Knee

BackgroundNutritionally compromized patients, with preoperative serum albumin (SAB) < 3.5g/dL, are at higher risk for periprosthetic joint infection (PJI) in total joint arthroplasty. The relationship between nutritional and PJI treatment success is unknown. The purpose of this study was to examine the relationship between preresection nutrition and success after first-stage resection in planned two-stage exchange for PJI.MethodsA retrospective review was performed on 418 patients who had first-stage resection of a planned two-stage exchange for chronic hip or knee PJI between 2014 and 2018. A total of 157 patients (58 hips and 99 knees) were included who completed first stage, had available preop SAB and had a 2-year follow-up. Failure was defined as persistent infection or repeat surgery for infection after resection. Demographic and surgical data were abstracted and analyzed.ResultsAmong knee patients with preop SAB >3.5 g/dL, the failure rate was 32% (15 of 47) versus a 48% (25 of 40) failure rate when SAB <3.5 g/dL (P = .10). Similarly, the failure rate among hip patients with preop SAB >3.5 g/dL versus 12.5% (3 of 24) versus 44% (15 of 34) for hip patients with SAB <3.5 g/dL (P = .01). Multivariable regression results indicated that patients with SAB< 3.5 g/dL (P = .0143) and Musculoskeletal Infection Society host type C (P = .0316) were at an increased risk of failure.ConclusionLow preoperative SAB and Musculoskeletal Infection Societyhost type-C are independent risk factors for failure following first-stage resection in planned two-stage exchange for PJI. Efforts to nutritionally optimize PJI patients, when possible, may improve the outcome of two-stage exchange.     

Hospital Costs for Unsuccessful Two-Stage Revisions for Periprosthetic Joint Infection

BackgroundAlthough 2-stage exchange arthroplasty is the preferred surgical treatment for periprosthetic joint infection (PJI) in the United States, little is known about the risk of complications between stages, mortality, and the economic burden of unsuccessful 2-stage procedures.MethodsThe 2015-2019 Medicare 100% inpatient sample was used to identify 2-stage PJI revisions in total hip and knee arthroplasty patients using procedural codes. We used the Fine and Gray sub-distribution adaptation of the conventional Kaplan-Meier method to estimate the probability of completing the second stage of the 2-stage PJI infection treatment, accounting for death as a competing risk. Hospital costs were estimated from the hospital charges using “cost-to-charge” ratios from Centers for Medicare and Medicaid Services.ResultsA total of 5094 total hip arthroplasty and 13,062 total knee arthroplasty patients had an index revision for PJI during the study period. In the first 12 months following the first-stage explantation, the likelihood of completing a second-stage PJI revision was 43.1% (95% confidence interval [CI] 41.7-44.5) for hips and 47.9% (95% CI 47.0-48.8) for knees. Following explantation, 1-year patient survival rates for hip and knee patients were 87.4% (95% CI 85.8-88.9) and 91.4% (95% CI 90.6-92.2), respectively. The median additional cost for hospitalizations between stages was $23,582 and $20,965 per patient for hips and knees, respectively. Hospital volume, Northeast or Midwest region, and younger age were associated with reduced PJI costs (P < .05).ConclusionAlthough viewed as the most preferred, the 2-stage revision strategy for PJI had less than a 50% chance of successful completion within the first year, and was associated with high mortality rates and substantial costs for treatment failure.     

Urinary tract infections diagnosed within two weeks prior to shoulder arthroplasty are associated with increased postoperative infection rates

BackgroundAlthough literature describing the increased risk of postoperative infection for patients undergoing lower extremity arthroplasty with a preoperative urinary tract infection (UTI) is inconclusive, this relationship has yet to be adequately studied for shoulder arthroplasty. The goals of the present study were to examine the association between preoperative UTIs and their timing with periprosthetic joint infection (PJI) after shoulder arthroplasty.MethodsPatients undergoing primary shoulder arthroplasty diagnosed with a UTI in the preoperative period were identified in an insurance database and separated into mutually exclusive groups based on one-week intervals up to six weeks before surgery. A matched control cohort without a preoperative UTI was created for comparison. The incidence of PJI within two years after shoulder arthroplasty was then assessed for each cohort and compared using a logistic regression analysis.ResultsCompared with matched controls, patients with a UTI diagnosed within 1 week before shoulder arthroplasty (odds ratio, 2.73; 95% confidence interval, 1.67-4.46; P < .001) and within 1 to 2 weeks preoperatively (odds ratio, 1.77; 95% confidence interval, 1.24-2.52; P = .002) experienced significantly higher rates of PJI within 2 years postoperatively. There were no significant differences in the incidence of PJI between patients diagnosed with a UTI greater than 2 weeks before surgery and matched controls (P > .05).ConclusionPatients diagnosed with a UTI within 2 weeks before shoulder arthroplasty may be at an increased risk of postoperative PJI.Level of evidenceLevel III, Database Case-control Prognosis Study     

Preoperative Opioid Use Is Associated With Higher Revision Rates in Total Joint Arthroplasty: A Systematic Review

BackgroundAlthough preoperative opioid use has been associated with poor postoperative patient-reported outcome measures and delayed return to work in patients undergoing total joint arthroplasty, direct surgery-related complications in patients on chronic opioids are still not clear. Thus, we sought to perform a systematic review of the literature to evaluate the influence of preoperative opioid use on postoperative complications and revision following primary total joint arthroplasty.MethodsFollowing the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement, we queried PubMed, EMBASE, the Cochrane Library, and the ISI Web of Science for studies investigating the influence of preoperative opioid use on postoperative complications following total hip arthroplasty and total knee arthroplasty up to May 2020.ResultsAfter applying exclusion criteria, 10 studies were included in the analysis which represented 87,165 opioid users (OU) and 5,214,010 nonopioid users (NOU). The overall revision rate in the OU group was 4.79% (3846 of 80,303 patients) compared to 1.21% in the NOU group (43,719 of 3,613,211 patients). There was a higher risk of aseptic loosening (odds ratio [OR] 1.30, 95% confidence interval [CI] 1.11-1.53, P = .002), periprosthetic fractures (OR 1.89, 95% CI 1.53-2.34, P < .00001), and dislocations (OR 1.26, 95% CI 1.14-1.39, P < .00001) in the OU group compared to the NOU group. Overall, 5 of 6 studies reporting on periprosthetic joint infection (PJI) rates showed statistically significant correlation between preoperative opioid use and higher PJI rates.ConclusionThere is strong evidence that preoperative opioid use is associated with a higher overall revision rate for aseptic loosening, periprosthetic fractures, and dislocation, and an increased risk for PJI.Level of EvidenceLevel III, systematic review.     

Measuring Surgical Site Infection From Linked Administrative Data Following Hip and Knee Replacement

BackgroundSurgical site infections (SSIs) in hip and knee arthroplasty are increasing internationally. Current trends in SSI monitoring use single source administrative databases with data collection points commonly at 30 or 90 days. We hypothesize that SSI rates are being under-reported due to methodological biases.MethodsData from multiple administrative data sets were contrasted and compared to look at the 90-day SSI rates for hip and knee arthroplasty in a single province from 2001 to 2015. SSI rates were calculated over time by year, and the differences in infection rates between single and multiple administrative data sets were calculated as an estimate of under reporting rates of SSIs. Days until diagnosis was measured for those diagnosed with an infection within 1 year.ResultsCombining administrative data sets indicates that hospital-based data underestimate SSI rates by 0.44 (P < .0001) of a percentage point over all years, a clinically significant result given the overall infection rate of 2.2% over the period. Less than 50% of hip and knee arthroplasty was recorded as infected by 30 days and approximately 75% of cases were recorded as infected by 90 days.ConclusionSingle source administrative data sets and short follow-up periods underestimate SSI rates. Administrative data sets should be combined and a minimum follow-up period of 90 days should be used to more accurately track SSI rates in hip and knee arthroplasty.     

Surgical Helmet Systems Are Associated With a Lower Rate of Prosthetic Joint Infection After Total Knee Arthroplasty: Combined Results From the New Zealand Joint Registry and Surgical Site Infection Improvement Programme

BackgroundThis study aimed to identify the risk factors, in particular the use of surgical helmet systems (SHSs), for prosthetic joint infection (PJI) after total knee arthroplasty (TKA). Data recorded by the New Zealand Surgical Site Infection Improvement Programme (SSIIP) and the New Zealand Joint Registry (NZJR) were combined and analyzed.MethodsPrimary TKA procedures performed between July 2013 and June 2018 that were recorded by both the SSIIP and NZJR were analyzed. Two primary outcomes were measured: (1) PJI within 90 days as recorded by the SSIIP and (2) revision TKA for deep infection within 6 months as recorded by the NZJR. Univariate and multivariate analyses were performed to identify risk factors for both outcomes with results considered significant at P < .05.ResultsA total of 19,322 primary TKAs were recorded by both databases in which 97 patients had a PJI within 90 days as recorded by the SSIIP (0.50%), and 90 patients had a revision TKA for deep infection within 6 months (0.47%) as recorded by the NZJR. An SHS was associated with a lower rate of PJI (adjusted odds ratio [OR] = 0.50, P = .008) and revision for deep infection (adjusted OR = 0.55, P = .022) than conventional gowning. Male sex (adjusted OR = 2.6, P < .001) and an American Society of Anesthesiologists score >2 were patient risk factors for infection (OR = 2.63, P < .001 for PJI and OR = 1.75, P = .017 for revision for deep infection).ConclusionUsing contemporary data from the SSIIP and NZJR, the use of the SHS was associated with a lower rate of PJI after primary TKA than conventional surgical gowning. Male sex and a higher American Society of Anesthesiologists score continue to be risk factors for infection.     

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.     

Do Positive Cultures at Second Stage Re-Implantation Increase the Risk for Reinfection in Two-Stage Exchange for Periprosthetic Joint Infection?

BackgroundIntraoperative cultures are important in the diagnosis and targeted treatment of periprosthetic joint infection (PJI). Positive cultures at reimplantation during a two-stage exchange are discussed as a risk factor for reinfection. The aim of this study is the investigation of the incidence and risk factors for positive cultures during reimplantation.MethodsWe retrospectively identified 204 patients (111 knees, 93 hips) who were treated between 2012 and 2016 for PJI using a two-stage exchange protocol at a median follow-up of 42 months. PJI was diagnosed using the criteria of the musculoskeletal infection society (MSIS) of 2011. All cultural findings from first and second stage surgery were recorded. The primary endpoint was revision for infection. Risk factors for positive cultures and reinfection were analyzed.ResultsDuring reimplantation 25% (51/204) of patients had at least one positive culture, in 19.1% (39/204) only a single culture. Patients with culture-negative infections had a higher risk for positive cultures at reimplantation (HR 2.946 (95% CI 1.247-6.961), P = .014) and patients with infected total hip arthroplasty (THA) (HR 3.547 (95% CI 1.7-7.4), P = .001). Patients with positive cultures during reimplantation had a higher risk for reinfection (HR 2.27 (95% CI 1.181-4.363), P = .014) as well as patients with a single positive culture (HR 2.421 (95% CI 1.139-5.143), P = .021).ConclusionAs positive cultures are common and increase reinfection risk irrespective of their numbers, longer antibiotic therapy following reimplantation can be an option. Single positive cultures in reimplantation surgery should not be considered contamination.     

Do Extended Oral Postoperative Antibiotics Prevent Early Periprosthetic Joint Infection in Morbidly Obese Patients Undergoing Primary Total Joint Arthroplasty?

BackgroundExtended oral antibiotic prophylaxis after primary total knee arthroplasty (TKA) and total hip arthroplasty (THA) in patients with body mass index (BMI) ≥40 kg/m² may reduce the rate of early periprosthetic joint infection (PJI); however, existing data are limited. The purpose of this study was to examine rates of wound complications and PJI in patients with BMI ≥40 kg/m² treated with and without extended oral antibiotic prophylaxis after surgery.MethodsWe retrospectively identified all primary THA and TKA performed since 2015 in patients with a BMI ≥40 kg/m² at a single institution. Extended oral antibiotic prophylaxis for 7-14 days after surgery was prescribed at the discretion of each surgeon. Wound complications and PJI were examined at 90 days postoperatively.ResultsIn total, 650 cases (205 THA and 445 TKA) were analyzed. Mean age was 58 years and 62% were women. Mean BMI was 44 kg/m². Extended oral antibiotic prophylaxis was prescribed in 177 cases (27%). At 90 days, there was no difference between prophylaxis and nonprophylaxis groups in rate of wound complications (11% vs 8%; P = .41) or PJI (1.7% vs 0.6%; P = .35). The univariate analysis demonstrated increased operative time (odds ratio (OR) 1.01; 95% confidence interval (95% CI) 1.01-1.02) and diabetes mellitus (OR 1.88; 95% CI 1.03-3.46) to be associated with increased risk of 90-day wound complications. No patient factors were associated with increased risk of PJI at 90 days postoperatively.ConclusionExtended oral antibiotic prophylaxis after primary THA and TKA did not reduce rates of wound complications or early PJI in a morbidly obese patient population.