Organic Peroxides in Aerosol: Key Reactive Intermediates for Multiphase Processes in the Atmosphere.

Organic peroxides (POs) are organic molecules with one or more peroxide (-O-O-) functional groups. POs are commonly regarded as chemically labile termination products from gas-phase radical chemistry and therefore serve as temporary reservoirs for oxidative radicals (HOx and ROx) in the atmosphere. Owing to their ubiquity, active gas-particle partitioning behavior, and reactivity, POs are key reactive intermediates in atmospheric multiphase processes determining the life cycle (formation, growth, and aging), climate, and health impacts of aerosol. However, there remain substantial gaps in the origin, molecular diversity, and fate of POs due to their complex nature and dynamic behavior. Here, we summarize the current understanding on atmospheric POs, with a focus on their identification and quantification, state-of-the-art analytical developments, molecular-level formation mechanisms, multiphase chemical transformation pathways, as well as environmental and health impacts. We find that interactions with SO2 and transition metal ions are generally the fast PO transformation pathways in atmospheric liquid water, with lifetimes estimated to be minutes to hours, while hydrolysis is particularly important for α-substituted hydroperoxides. Meanwhile, photolysis and thermolysis are likely minor sinks for POs. These multiphase PO transformation pathways are distinctly different from their gas-phase fates, such as photolysis and reaction with OH radicals, which highlights the need to understand the multiphase partitioning of POs. By summarizing the current advances and remaining challenges for the investigation of POs, we propose future research priorities regarding their origin, fate, and impacts in the atmosphere.

The Impact of Broadband Infrastructure Construction on Medical Resource Mismatch: Quasi-Natural Experiment From the Broadband China Policy.

BACKGROUND: Whether the construction of broadband infrastructure can alleviate the problem of mismatched medical resources is crucial to the national information strategy, residents' well-being, and social equity. However, the academic community lacks a comprehensive theoretical analysis and rigorous empirical research on this issue. OBJECTIVE: This study aims to construct a preliminary theoretical framework to scientifically assess the effects of broadband infrastructure development on the mitigation of health care resource mismatch from both theoretical and empirical perspectives, to explore the potential mechanisms of influence, and ultimately to develop several practical policy recommendations. METHODS: We first used a theoretical analysis to propose testable theoretical hypotheses and establish a preliminary theoretical framework. Then, based on balanced panel data from 300 cities from 2010 to 2021, a 2-way fixed effects difference-in-differences model was used for empirical testing. Mechanism tests, robustness analyses, and heterogeneity analyses were further conducted. RESULTS: The research findings demonstrate that the Broadband China Policy significantly reduces the degree of mismatch in medical resources by primarily using innovation effects and integration effects, resulting in a reduction of 13.2%. In addition, the heterogeneity analysis reveals that the central and eastern regions, cities with large populations, and areas with a high proportion of young people benefit more significantly. CONCLUSIONS: This study fully confirms, both theoretically and empirically, that broadband infrastructure construction can effectively reduce the mismatch of medical resources not only by expanding the existing literature on the impact of broadband on public services but also by providing valuable opportunities for policy makers to optimize the allocation of medical resources.

Curtailing infection risks in hepatitis C patients: the effect of antiviral treatment in revision shoulder arthroplasty.

BACKGROUND: Revision shoulder arthroplasty (RevSA) is a complex procedure that can result in various postoperative complications. However, the impact of hepatitis C virus (HCV) on postoperative complications after RevSA remains unclear because of limited and inconsistent evidence. This study aims (1) to investigate the incidence of postoperative complications in patients with HCV undergoing RevSA and (2) to evaluate the impact of HCV treatment on complication rates at different time points after the revision procedure, specifically at 90 days, 1 year, and 2 years. METHODS: We queried a national, all-payer database to investigate recent trends in the use of RevSA among HCV patients to assess postoperative complication rates, including venous thromboembolism (VTE), wound complication, transfusion, and periprosthetic joint infection (PJI). Statistical analyses involved propensity score matching to create balanced cohorts and logistic regression to determine the relative risk of postoperative complications. Data were analyzed with SPSS software (version 24.0 for Windows). The study included patients who underwent partial or total RevSA procedures between January 1, 2010, and December 31, 2020. Patients were identified based on medical claims that included procedural codes for RevSA and associated diagnosis codes for PJI or insertion/removal of an antibiotic spacer. A Bonferroni correction was used because many tests were performed and statistical significance was set at P = .0125. RESULTS: The HCV cohort demonstrated higher PJI rates at 1-year (5.5% vs. 3.9%, P = .006) and 2-year follow-ups (6.7% vs. 4.6%, P = .006). However, no significant differences emerged in VTE and wound complication rates between the HCV and non-HCV cohorts. Comparing untreated and treated HCV patients, the former showed significantly higher PJI rates at 2 years (P = .010), whereas the treated group had significantly lower odds ratios for PJI. When comparing treated HCV patients with the non-HCV cohort, minimal differences were found in postoperative outcomes, indicating no significant difference in the risk of complications between the groups. CONCLUSION: Our study observed an association between HCV patients who received antiviral treatment prior to RevSA and a reduced incidence of PJI compared to untreated HCV patients. When comparing this group to the non-HCV controls, there was no significant difference in the incidence of PJI, suggesting a potential association between antiviral treatment and the observed risk patterns in HCV patients. Proper management of HCV-positive patients during RevSA is crucial for improving outcomes and reducing complications.

Staged Approach to Tibial Nail Removal Poses Increased Risk for Infection in the Setting of Total Knee Arthroplasty.

BACKGROUND: While previous research has addressed conversion arthroplasty scenarios, there is limited data on outcomes of staged or concurrent removal of intramedullary (IM) nails during total knee arthroplasty (TKA). Our study aimed to explore the association between the timing of IM nail removal and the incidence of periprosthetic joint infection (PJI), surgical site infection (SSI), manipulation under anesthesia (MUA), and aseptic revision at 90 days, 1 year, and 2 years after TKA when IM nail removal is performed in either a (1) staged or (2) concurrent manner. METHODS: We queried a national, all-payer database of all patients who underwent a primary TKA and hardware removal of an IM tibial nail. The group was separated into mutually exclusive cohorts with removal performed either (1) in a staged manner (n = 287) or (2) on the same day of TKA (n = 2,958). Surgical complications included the following: PJIs, SSIs, MUAs, and aseptic revisions. Surgical complications were collected at 90-day, 1 year, and 2-year time points. RESULTS: Patients who had staged nail removal before TKA demonstrated the highest incidence of PJI at 90 days, 1 year, and 2 years (13.9, 16.7, and 17.1%, respectively). Adjusted multivariate regression analyses demonstrated significantly higher odds of a PJI, SSI, and MUA at 90 days, 1 year, and 2 years for all patients who had staged nail removal TKA (P < .001). CONCLUSIONS: There was an observed association between concurrent IM nail removal and a decreased risk of PJI, SSI, and MUA when compared to patients who had nail removal in a staged fashion. However, this does not discount the utility of the staged approach, as it may be necessary for patients less tolerant to longer operative times.

Stroke History and Time Elapsed are Predictors of Complications in Total Knee Arthroplasty.

BACKGROUND: A consensus has not been reached regarding the optimal timing of elective total knee arthroplasty (TKA) following a stroke. The purpose of this study was to examine the optimal period between stroke and TKA to minimize complications. Specifically, we assessed: (1) medical and surgical complications; (2) timing of stroke and TKA; (3) associated risk factors. METHODS: A national database identified 69,815 TKA patients that were separated into 6 exclusive cohorts using a stratum likelihood ratio: no stroke (n = 20,000), stroke within 6 (n = 17,764), 12 (n = 10,338), 18 (n = 8,370), 24 (n = 7,121), and 30 months (n = 6,222) prior to TKA. We analyzed 90-day, 1-year, and 2-year complications in each subgroup. Multivariate analyses were used to identify risk factors for periprosthetic joint infection (PJI). RESULTS: The multivariate regression model identified that patients with a stroke within 6 months of TKA had increased risk of PJI at all time points (P < .001). Also, stroke 12 to 18 months before TKA elevated PJI risk at 1 and 2 years (all P < .021), while those over 18 months did not show a significant risk compared to controls (P > .067). CONCLUSIONS: Stroke prior to TKA was associated with an increased risk of postoperative complications, specifically PJI. We recommend a minimum of 6 months between stroke and TKA, with 18 months offering the lowest risk.

Timing Matters: Optimizing the Timeframe for Preoperative Weight Loss to Mitigate Postoperative Infection Risks in Total Knee Arthroplasty.

BACKGROUND: We explore the incidence of periprosthetic infections post-total knee arthroplasty (TKA) in morbidly obese patients who achieved weight loss. Current American Academy of Orthopaedic Surgeons guidelines suggest a preoperative body mass index (BMI) below 40 for TKA. This study assesses infection risks in patients initially who had a BMI of 40-50 who reduced their BMI to under 35 at varying intervals prior to surgery. METHODS: We reviewed a national, all-payer database, PearlDiver, for patients undergoing primary TKA. Patients were stratified based on initial BMI of 40 to 50 and reduction of BMI to less than 35 at 3 months (n = 1,932), 3 to 6 months (n = 794), 6 to 9 months (n = 2,233), and 9 to 12 months (n = 1,194) prior to TKA, as well as patients who had a BMI between 40 to 50 (n = 41,632) on the day of surgery. The nonobese group comprised of patients who had a BMI between 20 and 30 (n = 33,294). Multivariate analyses were performed at one-year follow-up. RESULTS: We found an increased risk of PJI for patients who had achieved BMI reduction less than nine months prior to TKA, compared to the BMI 20 to 30 cohort at the one-year follow-up (P < .001). Patients who achieved BMI reduction nine to twelve months prior to TKA showed no significant difference in PJI risk compared to the matching nonobese cohort at one-year follow-up (P = .400). CONCLUSIONS: In conclusion, our results suggest that weight loss should be achieved at least nine months before TKA to decrease infection risks. These findings have significant implications for surgical considerations in obese patients undergoing TKA.

Are Metal Ion Levels Elevated After Dual Mobility Acetabular Systems: Minimum Five-Year Analyses.

INTRODUCTION: While dual mobility systems in total hip replacements have demonstrated reduced dislocation and revision occurrences, concerns persist about the potential elevation of metal ions in the bloodstream, leading to negative tissue reactions. Notably, there's a scarcity of research spanning over five years post-surgery that examines cobalt and chromium levels after such implants. This study aimed to delve into these metal ion concentrations after a five-year period, building on previous metal-ion findings. We focused on: (1) cobalt concentrations in blood and urine; (2) chromium concentrations in blood and urine; (3) cobalt variations based on follow-up duration and specific implant metrics (e.g., offset, cup dimension, stem, and neck inclination); and (4) chromium variations based on the same parameters. MATERIALS AND METHODS: We tracked 57 individuals who received THA using modular dual mobility systems from January 1, 2011, to December 31, 2016, for an average span of six years (ranging from five to 10 years). At the final check-up, we measured cobalt and chromium levels in serum, plasma, blood, and urine. We also evaluated parameters like head composition and dimension, stem offset, cup dimension, and stem-neck inclination. RESULTS: Cobalt concentrations remained minimal, with average blood and urine values being 0.8+0.6mcg/L (standard <1.8mcg/L) and 1.2+1.0mcg/L (standard <2.8mcg/L), respectively. Two individuals exhibited a slight increase in blood cobalt concentration by 0.1 and 0.2mcg/L. Chromium averages in blood and urine were also minimal, with readings of 0.9+0.2mcg/L (standard <1.2mcg/L) and 1.3 + 0.5mcg/L (standard <2mcg/L), respectively. One individual had a marginally increased blood chromium concentration of 1.3mcg/L. Evaluations considering ceramic or cobalt-chrome heads, up to a decade of follow up, or varying implant metrics showed negligible variations in metal ion concentrations. CONCLUSION: The findings reveal that over a minimum of five years (average = six years; span, five to 10 years), cobalt and chromium concentrations in patients' systems remained within normal limits and were clinically insignificant, irrespective of the follow-up duration, head material, or implant specifications. This underscores the efficacy of dual mobility systems in ensuring minimal metal ion presence.

Risk Factors Portending a Total Hip Arthroplasty for Patients Who Have Osteonecrosis of the Femoral Head.

INTRODUCTION: Osteonecrosis of the femoral head (ONFH) poses a substantial burden to orthopaedic surgeons. However, the exact risk attributed by each specific patient factor for those who end up receiving a total hip arthroplasty (THA) are not well known. We assessed: (1) patient demographics (age and sex); (2) blood cell dyscrasias (sickle-cell disease and hypercoagulable states); and (3) substance use (oral corticosteroid use, tobacco use, and alcohol abuse). MATERIALS AND METHODS: A retrospective search examined all patients who had a primary THA (n=715,100) between January 1, 2010 and April 30, 2020 using a national, all-payer database. Risk factors studied included age, sex, sickle-cell, hypercoagulable state, oral corticosteroid use, tobacco use, and alcohol abuse. RESULTS: Several risk factors were found to be significantly predictive for ONFH requiring THA: age <55 years (odds ratio [OR] 1.02, 95% confidence interval [CI] of 1.01 to 1.02, p<0.001), men (OR 1.07, 95% CI of 1.04 to 1.10, p<0.001), oral corticosteroid use (OR 1.21, 95% CI of 1.17 to 1.25, p<0.001), tobacco use (OR 1.15, 95% CI of 1.11 to 1.18, p<0.001), and alcohol abuse (OR 1.05, 95% CI of 1.01 to 1.08, p=0.009). CONCLUSIONS: Based on the results of this study, young age, men, oral corticosteroid use, tobacco use, and alcohol abuse are risk factors for patients who have ONFH and had a THA. The degree of risk from greatest to least were: oral corticosteroid use, tobacco use, men, alcohol abuse, and age <55 years old.

The use of preoperative continuous positive airway pressure in patients with obstructive sleep apnea following total knee arthroplasty: a propensity score matched analysis.

INTRODUCTION: Patients with sleep apnea, affecting up to 1 in 4 older men in the United States, may be at increased risk of postoperative complications after total knee arthroplasty (TKA), including increased thromboembolic and cerebrovascular events, as well as respiratory, cardiac, and digestive complications. However, the extent to which the use of CPAP in patients with sleep apnea has been studied in TKA is limited. METHODS: A national, all-payer database was queried to identify all patients who underwent a primary TKA between 2010 and 2021. Patients who had any history of sleep apnea were identified and then stratified based on the use of CPAP. A propensity score match analysis was conducted to limit the influence of confounders. Medical complications, such as cardiac arrest, stroke, pulmonary embolism, transfusion, venous thromboembolism, and wound complications, were collected at 90-days, 1-year, and 2-years. RESULTS: The bivariate analysis showed inferior outcomes for sleep apnea with CPAP use compared to sleep apnea with no CPAP use, in terms of length of stay (5.9 vs. 5.2, p < 0.001), PJI (1.31% vs. 1.14%, p < 0.001), stroke (0.97% vs. 0.82%, p < 0.001), VTE (1.04% vs. 0.82, p < 0.001), and all other complications at 90-days (p < 0.001) except cardiac arrest (0.14% vs. 0.11%, p = 0.052), and aseptic revision (0.40% vs. 0.39%, p = 0.832), PJI (1.81% vs. 1.55%, p < 0.001) and aseptic revision (1.25% vs. 1.06%, p < 0.001) at 1-year, and PJI (2.07 vs. 1.77, p < 0.001) and aseptic revision (1.98 vs. 1.17, p < 0.001) at 2-years. CONCLUSION: Patients with sleep apnea have increased postoperative complications after undergoing TKA in comparison to patients without sleep apnea. More severe sleep apnea, represented by CPAP usage in this study led to worse postoperative outcomes but further analysis is required signify the role of CPAP in this patient population. Patients with sleep apnea should be treated as a high-risk group.

Cemented is not superior to cementless total knee arthroplasty for complications: a propensity score matched analysis.

INTRODUCTION: There is continued debate regarding the survivorship and revision rate of cementless versus cemented total knee arthroplasty (TKA) prostheses. This includes the assessment of early revision surgery due to aseptic loosenings and periprosthetic joint infections (PJIs). Studies have not always taken into account the impact of comorbidities, such as diabetes, obesity, and tobacco. Therefore, we compared revisions in a large population of patients undergoing cemented or cementless TKAs at 90 days, 1 year, and 2 years. METHODS: A review of an administrative claims database was used to identify patients undergoing primary TKA, either cementless (n = 8,890) or cemented (n = 215,460), from October 1, 2015 to October 31, 2020. Revision surgery for PJI and aseptic loosening were identified with diagnosis and associated procedural codes at 90 days, 1 year, and 2 years and then compared between groups. A propensity matched-analysis was performed for age, sex, Charles Comorbidity Index (CCI) > 3, alcohol abuse, tobacco use, obesity, and diabetes. Chi square tests assessed statistical significance of differences in the matched cohorts using odds ratios (ORs) with 95% confidence intervals (CIs). A P < 0.05 was defined as statistically significant. RESULTS: Cementless TKA was associated with similar revisions rates due to PJIs at 90 days (OR, 1.04, 95% CI 0.79-1.38, p = 0.83), 1 year (OR, 0.93, 95% CI 0.75-1.14, p = 0.53, and 2 years (OR, 0.87, 95% CI 0.73-1.05, p = 0.17) in comparison to the cemented TKA cohort. The odds ratio of revision due to aseptic loosening was similar as well at 90 days (OR, 0.67, 95% CI 0.34-1.31, 0.31), 1 year (OR, 1.09, 95% CI 0.73-1.61, p = 0.76), and 2 years (OR, 1.00, 95% CI 0.73-1.61, p = 0.99). CONCLUSIONS: This study found a comparable risk of PJI and aseptic loosening in cementless and cemented TKA when controlling for several comorbidities, such as tobacco, diabetes, and alcohol. Therefore, with proper patient selection, cementless TKAs can be performed with expectation of low risks of infections and aseptic loosenings.

Elevated risk of prosthetic infections in cannabis users after shoulder arthroplasty.

INTRODUCTION: An increasing number of states are beginning to legalize recreational cannabis use, and as such, more patients using cannabis are undergoing shoulder arthroplasty procedures. The present study sought to examine the impact of cannabis use on post-operative outcomes. The primary outcomes of interest were postoperative complications, which included infection, periprosthetic fractures, periprosthetic joint infections (PJI), dislocations, and aseptic loosening as well as medical complications. Secondary outcomes were risk factors for PJI and aseptic loosening at two-years. METHODS: A private, nationwide, all-payer database (Pearldiver Technologies) was queried to identify shoulder arthroplasty patients from 2010 to 2020. Those not using tobacco or cannabis ("control", n = 10,000), tobacco users (n = 10,000), cannabis users (n = 155), and concurrent tobacco and cannabis users (n = 9,842) were identified. Risk factors for PJI and aseptic loosening at two-years were further quantified utilizing multivariable logistic regression analysis. RESULTS: Compared to non-users, cannabis users experienced the highest odds for PJI and aseptic revisions, which were followed by concurrent cannabis and tobacco users and tobacco-only users. Concurrent users, as well as tobacco users were at higher risk for dislocation. Cannabis use was the most significant risk factor for PJI, followed by concurrent use and male sex. CONCLUSIONS: Our study found cannabis use to cause greater risk for superficial and deep infection. More research involving randomized trials are needed to fully elucidate the impact of cannabis use on shoulder arthroplasty procedures. Clinically, these findings can appropriately guide surgeons and patients alike regarding expectations prior to undergoing TSA.

Open versus arthroscopic treatment of the rheumatoid elbow arthritis: a comparison of complications at two years utilizing a nationally representative database.

PURPOSE: Symptomatic rheumatoid arthritis (RA) can be addressed surgically with open procedures or elbow arthroscopy. Previous studies comparing outcomes of open to arthroscopic arthrolysis for the management of RA did not utilize a large database study. The aim was to compare demographics and two-year complications, in RA patients undergoing open or arthroscopic elbow arthrolysis. METHODS: A retrospective, cohort study was performed utilizing a private, nationwide, all-payer database. We queried the database to identify patients undergoing open (n = 578) or arthroscopic (n = 379) arthrolysis for elbow RA. The primary goal of the study was to compare complications at two-years. Categorical variables were assessed utilizing the chi-squared test; while, continuous variables were analyzed using the Student's t-test. Multivariable logistic regression was performed to assess risk factors for infection following open or arthroscopic arthrolysis. RESULTS: RA patients undergoing open elbow arthrolysis were older (55 vs. 49 years, p < 0.001), predominately female (61.6% vs 60.9%, p = 0.895), and likely to have chronic kidney disease (20.4 vs. 12.9%), and DM (45.2 vs. 32.2%) (both p < 0.005). Open elbow arthrolysis was also associated with higher rates of infection (31.7 vs. 4.7%) and wound complications (26.8 vs. 3.4%) (both p = 0.001). Nerve injury rates were found to be similar (8.3 vs. 9.0%, p = 0.81). On multivariable logistic regression, open elbow procedures were associated with the highest risk for infection (OR: 8.43). CONCLUSIONS: Patients undergoing open arthrolysis for RA were at a higher risk of infection and wound complications compared to arthroscopic arthrolysis utilizing a nationally representative database. While there appears to be a difference in outcomes following these two procedures, higher level evidence is needed to draw more definitive conclusions. LEVEL OF EVIDENCE: Retrospective, Level III.

How surface acting affects turnover intention among family doctors in rural China: the mediating role of emotional exhaustion and the moderating role of occupational commitment.

BACKGROUND: Family doctors in rural China are the main force for primary health care, but the workforce has not been well stabilized in recent years. Surface acting is an emotional labor strategy with a disparity between inner feelings and emotional displays, provoking negative effects such as emotional exhaustion, occupational commitment reduction, and, consequently, increasing turnover rate. With the Conservation of Resources theory, this study explores how the surface acting of rural family doctors affects turnover intention through emotional exhaustion and investigates what role occupational commitment plays in this relationship. METHODS: With a valid response rate of 93.89%, 953 valid data were collected by an anonymous self-administered questionnaire survey in December 2021 in Shandong Province, China. Cronbach's Alpha and confirmatory factor analysis (CFA) were used to estimate reliability and construct validity, respectively. The PROCESS macro in SPSS was performed to analyze the mediating and moderated mediation effects of surface acting, emotional exhaustion, occupational commitment, and turnover intention. RESULTS: Reliability and validity indicated that the measurement instruments were acceptable. Surface acting had a direct positive effect on turnover intention (ß = 0.481, 95% CI [0.420, 0.543]). Emotional exhaustion partially mediated the effect of surface acting on turnover intention (indirect effect: 0.214, 95% CI [0.175, 0.256]). Occupational commitment moderated the effect of emotional exhaustion on turnover intention (ß = - 0.065, 95% CI [- 0.111, - 0.019]), and moderated the indirect effect of surface acting on turnover intention via emotional exhaustion (index of moderated mediation: - 0.035). CONCLUSIONS: Emotional exhaustion partially mediates the relationship between surface acting and turnover intention among family doctors in rural China, and occupational commitment moderates the direct effect of emotional exhaustion on turnover intention and further moderates the mediating effect. Policymakers should pay more attention to the effects of emotional labor and emotional resource depletion on the stability of rural health human resources.

Does preoperative corticosteroid injection increase the risk of periprosthetic joint infection after reverse shoulder arthroplasty?

BACKGROUND: Corticosteroid injections (CSIs) are used for the symptomatic management of osteoarthritis. However, their use may contaminate the joint space and pose an increased risk of periprosthetic joint infection (PJI) following reverse shoulder arthroplasty (RSA). Therefore, the purpose of this study was to assess whether there is any association between the timing of CSI and the incidence of PJI at 90 days, 1 year, and 2 years postoperatively. Specifically, we assessed the risk of PJI in patients who received CSI <1 month, 1-2 months, 2-3 months, and >3 months prior to RSA, as well as associated risk factors for PJI with CSI. METHODS: We queried a national, all-payer database to identify patients who underwent RSA from October 1, 2015, to October 31, 2020 (1.5 million patients). Patients who received an osteoarthritis diagnosis prior to RSA were selected, whereas those with bilateral RSA or >1 injection on the same side were excluded. This resulted in 5 cohorts: cohort receiving CSI within 4 weeks of RSA (n = 5607), cohort receiving CSI 1-2 months prior to RSA (n = 3024), cohort receiving CSI 2-3 months prior to RSA (n = 1572), cohort receiving CSI >3 months prior to RSA (n = 16,302), and control cohort with no injection prior to RSA (n = 21,938). Bivariate χ2 analyses of outcomes were conducted, in addition to multivariate regressions performed to adjust for comorbidities, as well as to assess associated risk factors. RESULTS: The adjusted analyses demonstrated a significantly increased risk of PJI at 90 days in patients who received CSI within 1 month of RSA (P < .001). Additionally, the PJI risk was increased at 1 year postoperatively in patients who received CSI within 1 month of RSA (P = .015). However, no significant increase in the PJI risk was noted at any time point for patients who received CSI >1 month before RSA (all P ≥ .088). Furthermore, alcohol abuse, chronic kidney disease, and depression were identified as risk factors that increased the risk of PJI. CONCLUSION: Intra-articular shoulder CSIs <4 weeks prior to RSA are associated with increased risks of PJI at 90 days and 1 year postoperatively as compared with patients who did not receive CSIs. RSA should be deferred ≥4 weeks after a patient receives a CSI.

Core decompression is superior to nonoperative management for humeral head osteonecrosis: a systematic review.

BACKGROUND: Much of the literature on osteonecrosis has traditionally focused on the hip, which remains the most common site for this disease. The shoulder and the knee are the second most frequently affected sites (both approximately 10% of the incidence). There are a variety of techniques for managing this disease, and it is important to optimize this for our patients. This review aimed to compare the results of core decompression (CD) vs. nonoperative modalities for the treatment of osteonecrosis of the humeral head, including (1) success rate defined as lack of progression to further procedures (shoulder arthroplasty) and no need for further intervention; (2) clinical results (patient-reported pain and functional scores); and (3) radiological outcomes. METHODS: We queried PubMed and found 15 reports that fit the inclusion criteria for studies concerning the use of CD as well as studies discussing nonoperative treatment for stage I-III osteonecrotic lesions of the shoulder. A total of 9 studies encompassed 291 shoulders that underwent CD analyzed at a mean follow-up of 8.1 years (range, 67 months-12 years), and 6 studies examined 359 shoulders that underwent nonoperative management at a mean follow-up of 8.1 years (range, 35 months-10 years). Outcomes of CD and nonoperative management included success rate, number of shoulders requiring shoulder arthroplasty, and evaluation of several normalized patient-reported outcomes. We also assessed radiographic progression (pre- to postcollapse or further collapse progression). RESULTS: The mean success rate of CD for avoiding further procedures was 76.6% (226 of 291 shoulders) in stage I through stage III. Stage III shoulders avoided shoulder arthroplasty in 63% (27 of 43 shoulders). Nonoperative management resulted in a success rate of 13%, P < .001. In the CD studies, 7 of 9 showed improvements in clinical outcome measurements compared with 1 of 6 of the nonoperative studies. Radiographically, there was less progression in the CD group (39 of 191 shoulders [24.2%]) vs. the nonoperative group (39 of 74 shoulders [52.3%]) (P < .001). CONCLUSIONS: Given the high success rate and positive clinical outcomes reported, CD is an effective method for management, especially when compared with nonoperative treatment methods for stage I-III osteonecrosis of the humeral head. The authors believe that it should be used as treatment to avoid arthroplasty in patients who have osteonecrosis of the humeral head.

Less Than 1-Year Quiescent Period After Septic Arthritis of the Hip is Associated With High Risk of Periprosthetic Joint Infection Following Total Hip Arthroplasty.

BACKGROUND: Approximately 20,000 patients are diagnosed with septic arthritis annually, with 15% specifically affecting the hip joint. These cases exacerbate arthritic changes, often warranting a total hip arthroplasty (THA). Given their prior history of infection, these patients are predisposed to subsequent periprosthetic joint infections (PJIs). Multiple studies suggest delaying THA after a native septic hip, but no study utilizing a large cohort examined the specific timing to mitigate post-THA PJI risk within a short (<1 year) quiescent period after septic arthritis. We sought to compare patients who were diagnosed with septic hip arthritis at time intervals (0-6, or 6-12 months) prior to an ipsilateral primary THA to a cohort of THA patients who never had a septic hip history. Specifically, we assessed: from 90 days to 2 years (1) revisions due to PJI and (2) associated risk factors for PJI at 2-years. METHODS: A national, all-payer database was queried to identify all patients who underwent a primary THA between 2010 and 2021 and patients who had prior ipsilateral septic hip arthritis were characterized using International Classification of Disease and Current Practice Terminology codes (n = 1,052). A randomized sample of patients who never had a history of septic arthritis prior to undergoing THA was used as a nonseptic group comparison (n = 5,000). The incidences of PJI at 90 days through two years were then identified and compared using bivariate chi-square analyses. Risk factors for post-THA PJIs were then analyzed using multivariate regression models. RESULTS: The septic arthritis cohorts were more likely to require revisions due to PJIs, as compared to the non-septic group at 90 days, 1 year, and 2 years (all P < .0001). Patients who were diagnosed with septic arthritis between 0 and 6 months prior to THA were at greater PJI risk at both one-year (odds ratio (OR) of 43.1 versus 29.6, P < .0001) and two years (OR of 38.3 versus 22.1, P < .0001) compared to patients who had diagnoses between 6 and 12 months. Diabetes mellitus, obesity, and tobacco use were associated risk factors for PJIs at 2 years in the septic hip cohort in comparison to the cohort without a septic hip history. CONCLUSION: Less than a 1-year quiescent period after septic arthritis is associated with a 38 times increased risk and a 22 times risk for post-THA PJI, at 0 and 6 months and 6 and 12 months, respectively. Though patients who undergo THA greater than 6 months after their septic arthritis treatment have a decreased risk compared to those between 0 and 6 months the risks are still high. Orthopaedic surgeons should be aware of the increased risks of PJIs when considering performing a THA in patients with a history of septic arthritis.

Prior Septic Arthritis Within One Year of Knee Arthroplasty is Associated With a High Risk for Infection.

BACKGROUND: A prior history of a septic knee may predispose patients to a periprosthetic joint infection (PJI) after total knee arthroplasty (TKA). We performed multivariate analyses of known risk factors that portend a periprosthetic infection for patients who have a history of septic arthritis (SA). The focus of the study was an assessment of the incidence of TKA PJIs at various time intervals after the onset of a septic knee (0 to 3 months, 3 to 6 months, 6 to 9 months, and 9 months to 1-year). METHODS: We queried a national database to identify patients who underwent a primary TKA between 2010 and 2021 (n = 1.9 million). Patients who had a prior septic knee ipsilateral to the primary TKA were characterized (n = 4,251) and were put into four specific cohorts based on the interval between the SA diagnosis and TKA: less than 3 months; 3 to 6 months; 6 to 9 months; and 9 to 12 months. A cohort of patients who did not have history of septic knee were used for comparison (n = 5,000). The incidence of PJIs from 90 days to 1 year was identified and compared using multivariate analyses. RESULTS: All time cohorts were more likely to require revisions due to PJI, as compared to the comparison group. Significant differences were demonstrated among all time cohorts who had prior SA compared to patients who did not have a history of SA (odds ratio [OR] range, 90.0 to 113.0, P < .001). CONCLUSION: This study has shown an increased PJI risk in the first year after SA (P < .05). The surgeon should be aware of the increased PJI risk after SA within the first year after TKA.

Race Associated With Increased Complication Rates After Total Knee Arthroplasty.

BACKGROUND: Racial and ethnic disparities have been suggested to be associated with poor outcomes after total knee arthroplasty (TKA). While socioeconomic disadvantage has been studied, analyses of race as the primary variable are lacking. Therefore, we examined the potential differences between Black and White TKA recipients. Specifically, we assessed 30-day and 90-day, as well as 1 year: (1) emergency department visits and readmissions; (2) total complications; (3) as well as risk factors for total complications. METHODS: A consecutive series of 1,641 primary TKAs from January 2015 to December 2021 at a tertiary health care system were reviewed. Patients were stratified according to race, Black (n = 1,003) and White (n = 638). Outcomes of interest were analyzed using bivariate Chi-square and multivariate regressions. Demographic variables such as sex, American Society of Anesthesiologists classification, diabetes, congestive heart failure, chronic pulmonary disease, and socioeconomic status based on Area Deprivation Index were controlled for across all patients. RESULTS: The unadjusted analyses found that Black patients had an increased likelihood of 30-day emergency department visits and readmissions (P < .001). However, in the adjusted analyses, Black race was demonstrated to be a risk factor for increased total complications at all-time points (P ≤ .0279). Area Deprivation Index was not a risk for cumulative complications at these time points (P ≥ .2455). CONCLUSION: Black patients undergoing TKA may be at increased risk for complications with more risk factors including higher body mass index, tobacco use, substance abuse, chronic obstructive pulmonary disease, congestive heart failure, hypertension, chronic kidney disease, and diabetes and were thus, "sicker" initially than the White cohort. Surgeons are often treating these patients at the later stages of their diseases when risk factors are less modifiable, which necessitates a shift to early, preventable public health measures. While higher socioeconomic disadvantage has been associated with higher rates of complications, the results of this study suggest that race may play a greater role than previously thought.

Using a Google Web Search Analysis to Assess the Utility of ChatGPT in Total Joint Arthroplasty.

BACKGROUND: Rapid technological advancements have laid the foundations for the use of artificial intelligence in medicine. The promise of machine learning (ML) lies in its potential ability to improve treatment decision making, predict adverse outcomes, and streamline the management of perioperative healthcare. In an increasing consumer-focused health care model, unprecedented access to information may extend to patients using ChatGPT to gain insight into medical questions. The main objective of our study was to replicate a patient's internet search in order to assess the appropriateness of ChatGPT, a novel machine learning tool released in 2022 that provides dialogue responses to queries, in comparison to Google Web Search, the most widely used search engine in the United States today, as a resource for patients for online health information. For the 2 different search engines, we compared i) the most frequently asked questions (FAQs) associated with total knee arthroplasty (TKA) and total hip arthroplasty (THA) by question type and topic; ii) the answers to the most frequently asked questions; as well as iii) the FAQs yielding a numerical response. METHODS: A Google web search was performed with the following search terms: "total knee replacement" and "total hip replacement." These terms were individually entered and the first 10 FAQs were extracted along with the source of the associated website for each question. The following statements were inputted into ChatGPT: 1) "Perform a google search with the search term 'total knee replacement' and record the 10 most FAQs related to the search term" as well as 2) "Perform a google search with the search term 'total hip replacement' and record the 10 most FAQs related to the search term." A Google web search was repeated with the same search terms to identify the first 10 FAQs that included a numerical response for both "total knee replacement" and "total hip replacement." These questions were then inputted into ChatGPT and the questions and answers were recorded. RESULTS: There were 5 of 20 (25%) questions that were similar when performing a Google web search and a search of ChatGPT for all search terms. Of the 20 questions asked for the Google Web Search, 13 of 20 were provided by commercial websites. For ChatGPT, 15 of 20 (75%) questions were answered by government websites, with the most frequent one being PubMed. In terms of numerical questions, 11 of 20 (55%) of the most FAQs provided different responses between a Google web search and ChatGPT. CONCLUSION: A comparison of the FAQs by a Google web search with attempted replication by ChatGPT revealed heterogenous questions and responses for open and discrete questions. ChatGPT should remain a trending use as a potential resource to patients that needs further corroboration until its ability to provide credible information is verified and concordant with the goals of the physician and the patient alike.

Antibiotic Prophylaxis is Often Unnecessary for Screening Colonoscopies Following Total Knee Arthroplasty.

BACKGROUND: Incidence of bacteremia following screening colonoscopy is low, but risk of hematogenous spread causing prosthetic joint infection (PJI) may exist in total knee arthroplasty (TKA) patients. In multivariate analyses, we examined PJI risk among 3 TKA cohorts: (1) colonoscopy recipients given antibiotic prophylaxis; (2) colonoscopy recipients not given antibiotic prophylaxis; and (3) no colonoscopy. We assessed 90-day to 1-year (A) PJI risk and (B) risk factors for postcolonoscopy PJI. METHODS: We queried a national, all-payer database for primary TKA recipients from 2010 to 2020. Patients who had colonoscopies and who did (n = 2,558) or did not have antibiotic prophylaxis (n = 20,000) were identified. These were compared those who did not undergo colonoscopy (n = 20,000). The 20,000 patients were randomly selected to mitigate type-1 errors. Multivariate regressions compared PJI risk factors, such as alcohol abuse (AA), rheumatoid arthritis (RA), and diabetes. RESULTS: Both colonoscopy cohorts had no increased PJI risk compared to noncolonoscopy (odds ratio (OR) ≤ 2.20, P ≥ .064). Alcohol abuse, diabetes, and RA were found to be risk factors further enhancing likelihood of PJI for TKA patients not receiving antibiotics undergoing colonoscopies (OR ≥ 1.35, P ≤ .044). CONCLUSION: Overall, antibiotic prophylaxis does not decrease PJI risk following colonoscopy TKA recipients. After adjusting for known risk factors, both colonoscopy cohorts demonstrated similar PJI risks compared to the noncolonoscopy cohort. However, AA, diabetes, and RA were associated with further increased PJI risk for TKA patients undergoing colonoscopies compared to those who did not. Therefore, if undergoing colonoscopy after TKA, our findings suggest that most patients do not need to have antibiotics except for these high-risk patients.