Postoperative Bisphosphonates Use is Associated with Reduced Adverse Outcomes After Primary Total Joint Arthroplasty of Hip and Knee: A Nationwide Population-Based Cohort Study.

Bisphosphonates have been associated with a decreased risk of revision surgery after total joint arthroplasty of the hip or knee (TJA) because of their effects on decreased periprosthetic bone loss and prosthetic migration. However, the results in the early literature are inconsistent, and the influence of bisphosphonates on associated complications and subsequent TJA remains unknown. This study investigated the association between the use of bisphosphonates and the risk of adverse outcomes after primary TJA. This matched cohort study utilized the National Health Insurance Research Database in Taiwan to identify patients who underwent primary TJA over a 15-year period (January 2000-December 2015 inclusive). Study participants were further categorized into two groups, bisphosphonate users and nonusers, using propensity score matching. The Kaplan-Meier curve analysis and adjusted hazard ratios (aHRs) of revision surgery, adverse outcomes of primary surgery and subsequent TJA were calculated using Cox regression analysis. This study analyzed data from 6485 patients who underwent total hip arthroplasty (THA) and 20,920 patients who underwent total knee arthroplasty (TKA). The risk of revision hip and knee arthroplasty was significantly lower in the bisphosphonate users than in the nonusers (aHR, 0.54 and 0.53, respectively). Furthermore, the risk of a subsequent total joint arthroplasty, adverse events and all-cause mortality were also significantly reduced in the bisphosphonate users. This study, involving a large cohort of patients who underwent primary arthroplasties, revealed that bisphosphonate treatment may potentially reduce the risk of revision surgery and associated adverse outcomes. Furthermore, the use of bisphosphonates after TJA is also associated with a reduced need for subsequent arthroplasty.Research Registration Unique Identifying Number (UIN): ClinicalTrials.gov Identifier-NCT05623540 ( https://clinicaltrials.gov/show/NCT05623540 ).

Comprehensive Guidance for the Prevention of Periprosthetic Joint Infection After Total Joint Arthroplasty and Pitfalls in the Prevention.

Total joint arthroplasty (TJA) is a surgical procedure, in which parts of damaged joints are removed and replaced with a prosthesis. The main indication of TJA is osteoarthritis, and the volume of TJA is rising annually along with the increase of aged population. Hip and knee are the most common joints, in which TJAs are performed. The TJA prosthesis is composed of metal, plastic, or ceramic device. Even though TJA is the most successful treatment for end-stage osteoarthritis, it is associated with various complications, and periprosthetic joint infection (PJI) is the most serious complication after TJA. With the increasing volume of TJAs, there is a simultaneous rise in the incidence of PJI. Contamination of the surgical wound and the adherence of bacteria to the surface of prosthetic component represent the initial step in the pathogenesis of PJI. The main sources of the contamination are 1) patient's own flora, 2) droplets in the operation room air, and 3) surgical gloves and instruments. Even though modern techniques have markedly reduced the degree of contamination, TJAs cannot be done in completely germ-free conditions and some degree of contamination is inevitable in all surgical procedures. However, not all contamination leads to PJI. It develops when the burden of contamination exceeds the immune threshold or the colony forming units (CFUs) and various factors contribute to a decrease in the CFU level. Surgeons should be aware of the germ burden/CFU concept and should monitor sources of contamination to maintain the germ burden below the CFU to prevent PJI.

Validation of the Incidence of Reported Periprosthetic Joint Infections in Total Hip and Knee Arthroplasty in the Dutch Arthroplasty Register.

BACKGROUND: Arthroplasty registers underreport the incidence of periprosthetic joint infections (PJIs). We validated the incidence of reported PJIs in total hip arthroplasties (THAs) and total knee arthroplasties (TKAs) in the Dutch Arthroplasty Register (LROI) using data from the Dutch National Nosocomial Surveillance Network (PREZIES). METHODS: All primary THAs and TKAs from the LROI and all primary THAs and TKAs performed in consenting hospitals from PREZIES between 2012 and 2018 were matched on date of birth, date of surgery, sex, hospital, and type of procedure (THA n = 91,208; TKA n = 80,304). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for PJIs registered in the LROI, using PREZIES as a reference. RESULTS: The incidence of registered PJIs in THAs was 1.2% in PREZIES and 0.5% in the LROI. For TKAs, this was 0.7 and 0.4%, respectively. The PJIs in THAs in the LROI had a sensitivity of 0.32 (confidence interval [CI]: 0.29 to 0.35), specificity of 1.00 (CI: 1.00 to 1.00), PPV of 0.74 (CI: 0.70 to 0.78), and NPV of 0.99 (CI: 0.99 to 0.99). In TKAs, the sensitivity, specificity, PPV, and NPV were 0.38 (CI: 0.34 to 0.42), 1.00 (CI: 1.00 to 1.00), 0.65 (CI: 0.59 to 0.70), and 1.00 (CI: 1.00 to 1.00), respectively. CONCLUSIONS: The LROI captures approximately one-third of the PJIs as revision within one year for infection or resection arthroplasty. The capture rate of PJIs can be improved by including all reoperations without component exchange and nonsurgical treatments with antibiotics only.

Comparison of Outcomes in High Versus Low Activity Level Patients After Total Joint Arthroplasty.

BACKGROUND: Activity level (AL) recommendations following total joint arthroplasty (TJA) remain controversial. Our purpose was to compare implant survivorship of high activity (HA) and low activity (LA) patients after primary TJA. We hypothesized that there would be no difference in implant survivorship based on AL. METHODS: This was a retrospective 1:1 matched cohort study after primary TJA with minimum 5-year follow-up. High activity patients were designated by the University of California and Los Angeles activity-level rating scale score ≥8 and matched to LA patients based on age (±5), sex, and body mass index (±5). There were 396 HA patients (149 knees and 48 hips) who met inclusion criteria. We analyzed revision rates, adverse events, and radiographic lucencies. RESULTS: Crepitus was the most common adverse events in both HA and LA total knee arthroplasties (TKAs). Adverse events were rare in total hip arthroplasty (THA) cohorts. For both THA and TKA patients, the HA cohort did not have increased reoperations or revisions when compared to the LA cohort. No differences were noted in overall radiographic analysis between HA (16.1%) and LA (12.1%) TKA patients (P = .318), and in THA patients, more radiographic problems were noted in LA (P = .004). CONCLUSION: We found no difference in minimum 5-year postoperative implant survivorship based on AL. This may change AL recommendations after TKA and THA.

Lower Revenue Surplus in Medicare Advantage Versus Private Commercial Insurance for Total Joint Arthroplasty: An Analysis of a Single Payor Source at One Institution.

BACKGROUND: Since the Affordable Care Act was passed in 2010, reductions in Medicare reimbursement have led to larger discrepancies between the relative cost of Medicare patients and privately insured patients. The purpose of this study was to compare reimbursement between Medicare Advantage and other insurance plans in patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: Patients of a single commercial payor source who underwent primary unilateral TKA or THA at 1 institution between the dates of January 4 and June 30, 2021, were included (n = 833). Variables included insurance type, medical comorbidities, total costs, and surplus amounts. The primary outcome measure was revenue surplus between Medicare Advantage and Private Commercial plans. t-tests, Analyses of Variance, and Chi-Squared tests were used for analysis. A THA represented 47% of cases and a TKA 53%. Of these patients, 31.5% had Medicare Advantage and 68.5% had Private Commercial insurance. Medicare Advantage patients were older and had higher medical comorbidity risk for both TKA and THA. RESULTS: Significant differences were observed in medical costs between Medicare Advantage and Private Commercial insurance for THA ($17,148 versus $31,260, P < .001) and TKA ($16,723 versus $33,593, P < .001). Additionally, differences were seen in surplus amounts between Medicare Advantage and Private Commercial insurance for THA ($3,504 versus $7,128, P < .001) and TKA ($5,581 versus $10,477, P < .001). Deficits were higher in Private Commercial patients undergoing TKA (15.2 versus 6%, P = .001). CONCLUSION: The lower average surplus associated with Medicare Advantage plans may lead to financial strain on provider groups who care for these patients and face additional overhead costs.

Low-Dose Enteric-Coated and Chewable Aspirin Are Not Equally Effective in Preventing Venous Thromboembolism in Total Knee and Hip Arthroplasty.

BACKGROUND: Low-dose aspirin is an effective venous thromboembolism (VTE) prophylactic medication in primary total joint arthroplasty, but the efficacy and safety of the formulations of chewable and enteric-coated aspirin have not been compared. The purpose of this study was to investigate the VTE and gastrointestinal (GI) complication rates of chewable and enteric-coated 81 mg aspirin bis in die for VTE prophylaxis in primary total joint arthroplasty. METHODS: A retrospective, single-institution cohort study was performed on patients who underwent primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) from 2017 to 2021. Comparisons were made between 4,844 patients who received chewable, noncoated aspirin 81 mg and 4,388 patients who received enteric-coated 81 mg aspirin. Power analysis demonstrated 1,978 and 3,686 patients were needed per group to achieve a power of 80% for 90-day VTE rates (using inferiority testing) and GI complications (using superiority testing), respectively. Patients had similar baseline characteristics. Statistical analyses were done using t-tests and Chi-squared tests, with statistical significance defined as a P value < .05. RESULTS: There were no significant differences in the incidences of postoperative VTE (0.31% versus 0.55%; P = .111) or GI complications (0.14% versus 0.14%; P = 1.000) between patients who received either chewable or enteric-coated 81 mg aspirin bis in die in the overall comparison that included both THA and TKA patients combined, or THA patients alone. However, the VTE incidence for TKA patients alone was significantly lower with chewable than enteric-coated aspirin (0.22% versus 0.62%; P = .037), with no difference in GI complications (0.13% versus 0.19%; P = .277). CONCLUSIONS: Low-dose aspirin in enteric-coated formulation is inferior to chewable aspirin for VTE prophylaxis in primary TKA, but not inferior in THA patients. Both formulations have a similar GI complication rate. Therefore, it is reasonable to consider a transition from enteric-coated to uncoated chewable low-dose aspirin.

Racial Disparities in Treatment and Outcomes of Patients With Hepatitis C Undergoing Elective Total Joint Arthroplasty.

BACKGROUND: African Americans have the highest prevalence of chronic Hepatitis C virus (HCV) infection. Racial disparities in outcome are observed after elective total hip arthroplasty (THA) and total knee arthroplasty (TKA). This study sought to identify if disparities in treatments and outcomes exist between Black and White patients who have HCV prior to elective THA and TKA. METHODS: Patient demographics, comorbidities, HCV characteristics, perioperative variables, in-hospital outcomes, and postoperative complications at 1-year follow-up were collected and compared between the 2 races. Patients who have preoperative positive viral load (PVL) and undetectable viral load were identified. Chi-square and Fisher's exact tests were used to compare categorical variables, while 2-tailed Student's Kruskal-Wallis t-tests were used for continuous variables. A P value of less than .05 was statistically significant. RESULTS: The liver function parameters, including aspartate aminotransferase and model for end-stage liver disease scores, were all higher preoperatively in Black patients undergoing THA (P = .01; P < .001) and TKA (P = .03; P = .003), respectively. Black patients were more likely to undergo THA (65.8% versus 35.6%; P = .002) and TKA (72.1% versus 37.3%; 0.009) without receiving prior treatment for HCV. Consequently, Black patients had higher rates of preoperative PVL compared to White patients in both THA (66% versus 38%, P = .006) and TKA (72% versus 37%, P < .001) groups. Black patients had a longer length of stay for both THA (3.7 versus 3.3; P = .008) and TKA (4.1 versus 3.0; P = .02). CONCLUSIONS: The HCV treatment prior to THA and TKA with undetectable viral load has been shown to be a key factor in mitigating postoperative complications, including joint infection. We noted that Black patients were more likely to undergo joint arthroplasty who did not receive treatment and with a PVL. While PVL rates decreased over time for both races, a significant gap persists for Black patients.

Dexamethasone-Associated Hyperglycemia is Not Associated With Infectious Complications After Total Joint Arthroplasty in Diabetic Patients.

BACKGROUND: Postoperative infection is a devastating complication of total joint arthroplasty (TJA). Perioperative use of dexamethasone in patients who have diabetes mellitus (DM) remains controversial due to concern for increased infection risk. This study aimed to evaluate the association between dexamethasone and infection risk among patients who have DM undergoing TJA. METHODS: This was a retrospective cohort study conducted on adult patients who underwent primary, elective total knee arthroplasty (TKA) or total hip arthroplasty (THA) between January 2016 and December 2021 using a large national database. We identified 110,568 TJA patients (TKA: 66.6%; THA: 33.4%), 31.0% (34,298) of which had DM. Patients who received perioperative dexamethasone were compared to those who did not. The primary end points were the 90-day risk of postoperative periprosthetic joint infection, surgical site infection (SSI), and other non-SSI (urinary tract infection, pneumonia, sepsis). RESULTS: When modeling the association between dexamethasone exposure and study outcomes while accounting for the interaction between dexamethasone and morning blood glucose levels, dexamethasone administration conferred no increased odds of postoperative periprosthetic joint infection nor SSI in diabetics. However, dexamethasone significantly lowered the adjusted odds of other postoperative infections in diabetic patients (TKA: adjusted odds ratio = 09, 95% confidence interval = 0.8 to 1.0, P = .030; THA: adjusted odds ratio = 0.7, 95% confidence interval = 0.6 to 0.9, P = .001); specifically in patients with morning blood glucose levels between 110 to 248 mg/dL in TKA and ≤ 172 mg/dL in THA. CONCLUSIONS: This study provides strong evidence against withholding dexamethasone in diabetic patients undergoing TJA based on concern for infection. Instead, short-course perioperative dexamethasone reduced infection risk in select patients. The narrative surrounding dexamethasone should shift away from questions about whether dexamethasone is appropriate for diabetic patients, and instead focus on how best to optimize its use.

Unseen Threefold Mortality After the First Ten Days in Hemodialysis Patients Following Joint Arthroplasty: A Nationwide Retrospective Cohort Study of 1,287 Arthroplasty Patients on Hemodialysis.

BACKGROUND: The study addresses the growing number of hemodialysis (HD) patients undergoing joint arthroplasty, who are at higher risk of complications and mortality. Previous research has often overlooked deaths after discharge. This study aimed to examine early outcomes in a large nationwide cohort of patients who underwent arthroplasty for elective and fracture-related reasons. METHODS: Between 2016 and 2022, a study was conducted using the e-Nabiz database of the Türkiye Ministry of Health, focusing on patients aged 18 years and above who underwent elective or fracture-related arthroplasty. This study included 1,287 patients reliant on dialysis who underwent total hip arthroplasty, total knee arthroplasty, or hemiarthroplasty (HA), with 7.7% of them receiving dialysis for the first time. Propensity score matching was used to create an equally sized group of non-dialysis-dependent patients, ensuring demographic balance in terms of age, sex, a comorbidity index, and surgery type. The primary objective was to compare mortality rates 10, 30, and 90 days after arthroplasty. RESULTS: The first-time dialysis patients who underwent HA had significantly higher 30- and 90-day mortality rates compared to the chronic dialysis group (P = .040 and P < .001, respectively). Also, the HD patients consistently exhibited higher 90-day mortality rates across all surgery types. With total knee arthroplasty, HD patients had a mortality rate of 8.7%, in stark contrast to 0% among non-HD patients (P < .001). Similarly, with total hip arthroplasty, HD patients had a 12% mortality rate, while non-HD patients had a markedly lower rate of 2.7% (P = .008). In the case of HA, HD patients had a significantly elevated 90-day mortality rate of 31.9%, in contrast to 17.1% among non-HD patients (P < .001). CONCLUSIONS: Joint arthroplasty has higher rates of mortality and complications among HD patients. Surgical decisions must be based on patients' overall health, necessitating collaboration among specialists. These patients should be closely monitored.

Cannabis Use Following Total Joint Arthroplasty is Associated With Increased Risks? A Meta-Analysis.

BACKGROUND: With the increased legalization of cannabis, a new unknown emerges for orthopaedic surgeons and their patients. This systematic review aimed to (1) evaluate complications of cannabis use; (2) determine the effects of cannabis on pain and opioid consumption; and (3) evaluate healthcare utilizations associated with cannabis use among patients undergoing total joint arthroplasty (TJA). METHODS: A systematic review was performed. A search of the literature was performed in 5 databases. We included studies between January 2012 and July 2022 reporting cannabis use and complications, pain management, opioid consumption, length of stay, costs, or functional outcomes following TJA. A meta-analysis of odds ratios (ORs) and continuous variables was performed. A total of 19 articles were included in our final analysis. RESULTS: Cannabis use was associated with higher odds for deep vein thrombosis (DVT) (OR: 1.46, 95% Confidence Interval [CI]: 1.13 to 1.89) and revisions (OR: 1.47 [95% CI: 1.41 to 1.53]) in total knee arthroplasty (TKA). Cannabis use was associated with similar odds for DVT in total hip arthroplasty (THA) (OR: 1.30 [95% CI: 0.79 to 2.13]), pulmonary embolus in both TKA (OR: 1.29 [95% CI: 0.95 to 1.77]), THA (OR: 0.55 [95% CI: 0.09 to 3.28]), and cardiovascular complications in TKA (OR: 1.97 [95% Cl: 0.93 to 4.14]). Cannabis use did not alter pain scores, opioid consumption, or cost of care in THA (estimate: $2,550.51 [95% CI: $356.58 to $5,457.62]) but was associated with higher costs in TKA (estimate: $3,552.46 [95% CI: $1,729.71 to $5,375.22]). There was no difference in lengths of stay or functional outcomes; however, there may be a potentially increased risk for prosthetic complications, pneumonia, and cerebrovascular accidents among cannabis users. CONCLUSION: Cannabis use may be associated with an increased risk of DVTs, revisions, pneumonia, cerebrovascular accidents, and cardiac complications after TJA. Higher-level studies are needed to ascertain the impact of cannabis use for patients undergoing TJA.

How Reliable Is the Absolute Synovial Polymorphonuclear Neutrophil Cell Count in Diagnosing Periprosthetic Joint Infection?

BACKGROUND: Diagnosing periprosthetic joint infection (PJI) is a daunting task for even the most experienced orthopedic surgeons, as there is currently no test available that can provide absolute accuracy. Utilizing an established synovial indicator for detecting PJI without incurring additional costs or resources would be the optimal solution for predicting the presence of infection. Therefore, we hypothesized that synovial absolute neutrophil count (ANC) would improve the diagnostic accuracy of chronic knee and hip PJI. METHODS: The study included 260 patients (134 men and 126 women, mean age of 70 years [range, 26 to 89]) who underwent aspiration during preoperative workup. Of these, 109 patients (41.9%) were diagnosed with chronic PJI (50 knees, 59 hips), and 151 patients (58.1%) were diagnosed as aseptic (94 knees, 57 hips). Data obtained from all patients included age, sex, procedure type (total hip or total knee arthroplasty), operation side, synovial white blood cell count (cells/µL), synovial polymorphonuclear cells percentage, and synovial α-defensin immunoassay value at the admission were retrieved from the electronic medical record. RESULTS: The calculated optimal threshold for synovial ANC of 1,415.5 cells/µL was associated with an area under the receiver operating characteristic curve (AUC) of 0.930 for chronic knee PJI diagnosis. The calculated optimal threshold for synovial ANC of 2,247 cells/µL was associated with an AUC of 0.905 for chronic hip PJI diagnosis. CONCLUSIONS: This study has conclusively shown that the synovial ANC serves as a valuable marker in the complicated diagnosis of PJI. This highly effective and efficient approach should be utilized for obtaining further information through standard tests, thereby ruling out the possibility of PJI. LEVEL OF EVIDENCE: III.

Disparities Associated With Total Joint Arthroplasty Transfusion Rates.

BACKGROUND: Infections, readmissions, and mortalities after total joint arthroplasty (TJA) are serious complications, and transfusions have been associated with increased complication rates following TJA. Certain populations, including women, Black patients, patients who have public insurance and older adults have higher risks of transfusion. Recently, there has been a decline in transfusion rates and a greater emphasis on equity in medicine. This study examined whether disparities in transfusion rates still exist and what variables influence rates over time. METHODS: We used a health care system database to identify 5,435 total knee arthroplasty (TKA) and 2,105 total hip arthroplasty (THA) patients from 2013 to 2021. Transfusion rates were 2.9 and 3.1% in the TKA and THA arthroplasty groups, respectively. White race represented 67.1 and 69.8% of the TKA and THA groups, respectively. Fisher exact and Wilcoxon rank sum tests were used to compare categorical and continuous variables. Multivariable logistic regressions were performed to predict transfusion rates within 5 days of surgery and adjust for potential confounders. RESULTS: Transfusion rates declined over time. However, Black patients had a higher rate of transfusion than White patients despite similar hemoglobin levels, 5.1 versus 1.8% (P < .001) in the TKA group and 4.1 versus 2.7% (P = .103) in the THA group. Following adjustment, the biggest factor associated with a higher transfusion risk in the TKA group was being Black (adjusted odds ratio = 2.2, 95% confidence interval = 1.55 to 3.13). CONCLUSIONS: Transfusion rates for TJA patients are declining; however, Black patients continued to receive transfusions at higher rates in patients receiving TKA.

The Association Between Mental Health, Substance Use Disorder, and Outcomes After Total Joint Arthroplasty.

BACKGROUND: Prior studies suggest that distressed patients or those who have poor mental health have inferior postoperative outcomes when compared to nondistressed patients. However, these studies typically do not account for substance use or other comorbidities often found in this population, which can independently contribute to postoperative complications. This study sought to control for these factors and assess if a diagnosis of a mental health condition is directly associated with worse outcomes after total joint arthroplasty. METHODS: A retrospective chart review was performed for 3,182 patients who underwent a total hip arthroplasty and 4,430 patients who underwent a total knee arthroplasty. Diagnosis of the mental health disorders included depression, anxiety disorder, adjustment disorder, bipolar disorder, trauma, stressor-related disorder, and schizophrenia or schizoaffective disorder. Multivariable analyses were performed to control for alcohol use, drug use, tobacco use, body mass index, and a comorbidity index. RESULTS: When controlling for body mass index and Charlson comorbidity index, no statistically significant associations were found between a diagnosis of any mental health condition or a specific diagnosis of depression or anxiety, and 90-day readmission, reoperation, or 1 year mortality for patients undergoing total knee arthroplasty or total hip arthroplasty. CONCLUSIONS: When accounting for confounding factors, there does not appear to be a direct association between diagnosis of any of the psychiatric conditions we studied and outcomes after primary total joint arthroplasty. While prior studies suggest addressing the mental health condition may improve outcomes, this study suggests that preoperative medical optimization and potentially addressing substance use may be more effective strategies.

Patients Who Have a Prior History of Pulmonary Embolism Require Increased Postoperative Care Following Total Joint Arthroplasty.

BACKGROUND: This study examined the effect of prior pulmonary embolism (PE) on total joint arthroplasty (TJA) outcomes. METHODS: We reviewed patients who had a prior PE undergoing TJA at a single tertiary medical center between January 1, 2012 and January 1, 2021. There were 177 TJA patients who had a prior PE who underwent 1:3 propensity-matching to patients without a history of prior PE. Bivariable and multivariable analyses were performed. Changes over time were evaluated. RESULTS: Patients undergoing total knee arthroplasty who had a prior PE had more complications (25.3% versus 2.0%, P < .001), and postoperative PE (17.3% versus 0.0%, P < .001).and longer hospitalizations (3.15 versus 2.32 days, P = .006). Patients undergoing total hip arthroplasty who had a prior PE demonstrated more complications (14.7% versus 1.77%, P < .001) more postoperative PE (17.3% versus 0.0%, P < .001), and longer hospitalizations (3.30 versus 2.11 days, P < .001). Over the study, complication rates and hospitalizations lengths remained elevated in patients who had a prior PE. On multivariate analyses, prior PE was associated with longer hospitalizations (ß: 0.67, P = .015) and increased complications (odds ratio [OR]: 9.44, P < .001) among total hip arthroplasty patients. Total knee arthroplasty patients had increased readmission (OR: 4.89, P = .003) and complication rates (OR: 21.4, P < .001). CONCLUSIONS: Patients undergoing TJA who had a prior PE are at higher risk of requiring postoperative care. Therefore, thorough preoperative evaluation must be implemented, especially in clinical environments lacking resources for acute care escalation.

Medicaid Expansion Is Associated With Increases in Medicaid-Funded Total Joint Arthroplasty.

BACKGROUND: Existing literature presents competing views concerning the impact of Medicaid expansion on total joint arthroplasty (TJA) utilizations. While some reports demonstrate that expansion does not increase Medicaid acceptance by surgeons, others show increases in Medicaid-funded TJA via limited analyses. We conducted a nationwide, multi-insurance, econometric study to determine if Medicaid-funded and all-funding-source total hip arthroplasty (THA) or total knee arthroplasty (TKA) utilizations increased following expansion. METHODS: This study examined 999,015 THA and 2,099,975 TKA from 2010 to 2017 using a commercially available national payer database. Difference-in-differences analyses, econometric regression methods used to assess the impact of policy change, were used to examine the impact of Medicaid expansion on TJA utilizations, and event analyses were used to confirm the parallel trends assumption, which helps to ensure that the estimated effect is not a result of existing differences in trends between treatment and nontreatment groups. RESULTS: Event analyses confirmed parallel trends in the pre-expansion period. Difference-in-differences analyses found a persistent increase in Medicaid-funded THA (40.4%, P = .001, confidence interval [CI]: 12.7, 62.1%), but not THA from all funding sources (4.6%, P = .128, CI: -1.3, 10.8%). Medicaid-funded TKA (35.8%, P < .001, CI: 17.4, 68.0%) increased, but not TKA from all funding sources (3.4%, P = .321, CI: -3.1, 10.1%). CONCLUSION: While the number of Medicaid-funded TJAs increased, expansion had no significant effect when examining all funding sources. This suggests that Medicaid expansion primarily affected source of TJA funding, not overall volume. Further research is needed to examine state-specific predictors of response to Medicaid expansion.

Neutrophil to Lymphocyte Ratio and Periprosthetic Joint Infection: A Systematic Review and Meta-Analysis.

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR) has shown promising results as a diagnostic tool for periprosthetic joint infection (PJI) after total joint arthroplasty. We conducted a systematic review and meta-analysis to determine the utility of NLR in the diagnosis of PJI. METHODS: We searched PubMed, Scopus, and Web of Science from inception up to 2022 and evaluated the quality of the included literature. RESULTS: Based on the 12 eligible studies, NLR levels were significantly higher in patients who had PJI compared to those who had aseptic loosening (standard mean difference (SMD) = 1.05, 95% Confidence Interval (CI) = 0.71 to 1.40, P < .001). In the subgroup analysis according to type of PJI, NLR levels were significantly higher in patients who had either acute (SMD = 1.04, 95% CI = 0.05 to 2.03, P < .001) or chronic PJI (SMD = 1.08, 95% CI = 0.55 to 1.61, P < .001), compared to those who had aseptic loosening. According to type of arthroplasty, NLR levels were significantly higher in patients who had either total knee arthroplasty (SMD = 1.81, 95% CI = 1.48 to 2.13, P < .001) or total hip arthroplasty (SMD = 1.76, 95% CI = 1.54 to 1.98, P < .001) compared to aseptic loosening. The pooled sensitivity of the 12 studies was 0.73 (95% CI, 0.65 to 0.79), and the pooled specificity was 0.75 (95% CI, 0.71 to 0.78). The pooled positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of NLR were 2.94 (95% CI = 2.44 to 3.54), 0.35 (95% CI = 0.27 to 0.46), and 8.26 (95% CI = 5.42 to 12.58), respectively. CONCLUSION: In summary, this meta-analysis indicates that NLR is a reliable marker in the diagnosis of PJI.

Outpatient Total Joint Arthroplasty in the "Unhealthy": Staying Safe Using Institutional Protocols.

BACKGROUND: Recent expansion in the indications for outpatient total joint arthroplasty has led to debate over patient selection. The purpose of this study was to compare early clinical outcomes and complications of same-day discharge (SDD) hip and knee arthroplasties from a high-volume institution based on the American Society of Anesthesiologists (ASA) Physical Status Classification. METHODS: Prospectively collected data were reviewed for all SDD primary joint arthroplasties between January 2013 and August 2023. There were eight surgeons who performed 7,258 cases at hospital outpatient (n = 4,288) or ambulatory surgery centers (n = 2,970). This included 3,239 total hip arthroplasties (THAs), 1,503 total knee arthroplasties (TKAs), and 2,516 unicompartmental knee arthroplasties (UKAs). The ASA 1 group comprised 506 subjects, compared to 5,005 for ASA 2, and 1,736 for ASA 3. Primary outcomes included emergency department (ED) visits, readmissions, complications, and revisions within 24-hours and 90-days of surgery. The ASA 3 group was older (ASA1 = 55 versus ASA2 = 63 versus ASA3 = 66 years; P < 0.01) and had a higher body mass index (BMI) (ASA1 = 25.4 versus ASA2 = 28.5 versus ASA3 = 32.7; P < 0.01). RESULTS: There were no differences between ASA groups in joint-related ED visits, readmissions, and complications within 24-hours and 90-days of surgery (P > 0.05). Subjects in the ASA 3 group experienced greater 90-day revisions compared to the other groups (ASA1 = 1 of 506, 0.2% versus ASA2 = 15 of 5,005, 0.3% versus ASA3 = 15 of 1,736, 0.9%; P = 0.01). Regarding systemic events, ASA 1 subjects experienced significantly greater 24-hour complications (8 of 506, 1.6%) and ED visits (5 of 506, 1.0%), and ASA 3 subjects had a higher incidence of 90-day readmissions (19 of 1,736, 1.1%) compared to the other groups (P < 0.05). Within 24 hours of discharge, urinary retention and syncope were the most frequent complications that required additional healthcare utilization. CONCLUSIONS: Medically optimized patients categorized as ASA 3 can safely undergo SDD hip and knee arthroplasty without increased risk of 24-hour or 90-day complications. Patient preference for outpatient care, reliable social support, and independent functional status are imperative for a successful outpatient program.

Metabolic Syndrome Components and Its Impact on Acute Kidney Injury After Total Joint Arthroplasty.

BACKGROUND: Metabolic syndrome (MetS) is an independent risk factor for postoperative complications. This study aimed to evaluate the associated risk of MetS for perioperative complications, especially urinary complications, in patients who underwent primary total knee arthroplasty (TKA) or total hip arthroplasty (THA). METHODS: We used a publicly available all-payer administrative database to identify patients undergoing TKA and THA from 2016 to 2020. The primary exposure of interest was MetS. Multivariable adjusted models based on propensity score matching were used to evaluate the association of MetS components with acute kidney injury (AKI), urinary tract infection (UTI), and acute posthemorrhagic anemia (APHA) in patients who underwent TKA and THA. A counterfactual-based mediation analysis was conducted to investigate the mediating effect of APHA on the relationship between MetS and AKI. RESULTS: The analysis included 2,097,940 (16.4% with MetS) THA and 3,073,310 (24.0% with MetS) TKA adult hospitalizations. Multivariable adjustment analysis indicated MetS was associated with an increased risk of AKI (odds ratio [OR] 1.78, 95% confidence interval [CI] 1.69 to 1.89 for THA; OR 1.88, 95% CI 1.79 to 1.96 for TKA), UTI (OR 1.13, 95% CI 1.03 to 1.23 for THA; OR 1.26, 95% CI 1.17 to 1.35 for TKA), and APHA (OR 1.17, 95% CI 1.14 to 1.20 for THA; OR 1.7, 95% CI 1.15 to 1.19 for TKA). The risk of AKI increased with the number of MetS components, with ORs ranging from 2.58 to 9.46 in TKA patients and from 2.22 to 5.75 in THA patients. This increase was particularly associated with diabetes and hypertension, which were the most significant associated risk factors. Furthermore, APHA mediated the association between MetS and AKI. CONCLUSIONS: The prevalence of MetS is increasing in TKA and THA patients. Metabolic syndrome was associated with increased risk of AKI, UTI, and APHA. The risk of AKI increased with each additional MetS component, with diabetes and hypertension contributing most. In addition, APHA may play a partial mediating role in MetS-induced AKI.

Total Joint Arthroplasty Outcomes in Eligible Patients Versus Patients Who Failed to Meet at Least 1 Eligibility Criterion: A Single-Center Retrospective Analysis.

BACKGROUND: This study looks to investigate how not meeting eligibility criteria affects postoperative outcomes following total joint arthroplasty surgery. METHODS: A retrospective review was conducted of total joint arthroplasty patients at a single academic institution. Demographics, laboratory values, and complications were recorded. Continuous and categorical variables were compared using the Student's T-test and the Chi-Square test, respectively. Multivariable analysis was used to control for confounding variables. RESULTS: Our study included 915 total hip and 1,579 total knee arthroplasty patients. For total hip and total knee arthroplasty, there were no significant differences in complications (P = .11 and .87), readmissions (P = .83 and .2), or revision surgeries (P = .3 and 1) when comparing those who met all criteria to those who did not. Total hip arthroplasty patients who did not meet two criteria had 16.1 higher odds (P = .02) of suffering a complication. There were no differences in complications (P = .34 and .41), readmissions (P = 1 and .55), or revision surgeries (P = 1 and .36) between ineligible patients treated by total joint arthroplasty surgeons and those who were not. Multivariable analysis demonstrated no eligibility factors were associated with outcomes for both total hip and knee arthroplasty. CONCLUSIONS: There was no significant difference in outcomes between those who met all eligibility criteria and those who did not. Not meeting two criteria conferred significantly higher odds of suffering a complication for total hip arthroplasty patients. Total joint arthroplasty surgeons had similar outcomes to non-total joint surgeons, although their patient population was more complex. LEVEL OF EVIDENCE: III.

Validation of a Discharge Risk Calculator for Rural Patients Following Total Joint Arthroplasty.

BACKGROUND: As the volume of total joint arthroplasty in the US continues to grow, new challenges surrounding appropriate discharge surface. Arthroplasty literature has demonstrated discharge disposition to postacute care facilities carries major risks regarding the need for revision surgery, patient comorbidities, and financial burden. To quantify, categorize, and mitigate risks, a decision tool that uses preoperative patient variables has previously been published and validated using an urban patient population. The aim of our investigation was to validate the same predictive model using patients in a rural setting undergoing total knee arthroplasty (TKA) and total hip arthroplasty. METHODS: All TKA and THA procedures that were performed between January 2012 and September 2022 at our institution were collected. A total of 9,477 cases (39.6% TKA, 60.4% THA) were included for the validation analysis. There were 9 preoperative variables that were extracted in an automated fashion from the electronic medical record. Included patients were then run through the predictive model, generating a risk score representing that patient's differential risk of discharge to a skilled nursing facility versus home. Overall accuracy, sensitivity and specificity were calculated after obtaining risk scores. RESULTS: Score cutoff equally maximizing sensitivity and specificity was 0.23, and the proportion of correct classifications by the predictive tool in this study population was found to be 0.723, with an area under the curve of 0.788 - both higher than previously published accuracy levels. With the threshold of 0.23, sensitivity and specificity were found to be 0.720 and 0.723, respectively. CONCLUSIONS: The risk calculator showed very good accuracy, sensitivity, and specificity in predicting discharge location for rural patients undergoing TKA and THA, with accuracy even higher than in urban populations. The model provides an easy-to-use interface, with automation representing a viable tool in helping with shared decision-making regarding postoperative discharge plans.