The Current Epidemiology of Revision Total Knee Arthroplasty in the United States From 2016 to 2022.

BACKGROUND: The number of revision total knee arthroplasties (TKAs) is projected to reach 268,200 cases annually by 2030 in the United States. The growing demand for revision TKA can be attributed to the successes of primary TKAs combined with an aging population, patient desires to remain active, as well as expanded indications for younger patients. Given the evolving nature of revision TKAs, an epidemiological analysis of: (1) etiologies; (2) demographics, including age and region; as well as (3) lengths of stay (LOS) offers a way to minimize the gap between appropriate understanding and effective intervention. METHODS: From 2016 to 2022, a national, all-payer database was queried. Incidences and indications were analyzed for a total of 135,983 patients who had revision TKA procedures. RESULTS: The most common etiologies for revision TKA procedures were infection (19.3%) and aseptic loosening (12.8%), followed by mechanical complications (7.9%). The largest age group was 65 to 74 years (34.9%) followed by 55 to 64 years (32.2%), then age >75 years (20.5%). The South had the largest total procedure cohort (39.8%), followed by the Midwest (28.6%), then the Northeast (18.6%), and the West (13.0%). The mean length of stay was 3.86 days (range, 1.0 to 15.0). CONCLUSIONS: Our study details the current status of revision TKA through 2022. While infection and aseptic loosening remain leading causes, we found a low aseptic loosening rate of 12.8%.

Impact of Reporting Bias, Conflict of Interest, and Funding Sources on Quality of Orthopaedic Research.

BACKGROUND: Influence of factors like reporting outcomes, conflicts of interest, and funding sources on study outcomes, particularly positive outcomes in orthopedics, remains underexplored. As transparency of partnerships in orthopaedic surgery through conflicts of interest statements has increased over the years, there has been a lack of focus on the value of these partnerships in influencing study outcomes. We aimed to investigate the associations between reporting outcomes, conflicts of interest, and sources of funding on study outcomes. METHODS: We reviewed articles published in 1 year in The Journal of Bone and Joint Surgery, The American Journal of Sports Medicine, and The Journal of Arthroplasty. The abstracts were examined for appropriate inclusion, while the authors' names, academic degrees, funding disclosures, and departmental and institutional affiliations were redacted. There were a total of 1,351 publications reviewed from January 1, 2021 to December 31, 2021. RESULTS: A significant association was found between positive outcomes and reported conflicts of interest (75% versus 25%, P < .001). Likewise, conflicts of interest showed significant association with industry-sponsored studies (88% versus 12%, P < .001) and evidence level > II (72% versus 28%, P < .001). Industry-sponsored research accounted for the highest percentage of studies involving a conflict of interest (88%) and level I studies (12%). CONCLUSIONS: Conflicts of interest are significantly associated with positive outcomes in orthopaedics. Sponsored studies were more inclined to have conflicts of interest and accounted for the majority of level I studies.

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.

The Utility of the Social Vulnerability Index as a Proxy for Social Disparities Following Total Knee Arthroplasty.

BACKGROUND: In 2021, alternative payment models accounted for 40% of traditional Medicare reimbursements. As such, we sought to examine health disparities through a standardized categorization of social disparity using the social vulnerability index (SVI). We examined (1) risk factors for SVI ≥ 0.50, (2) incidences of complications, and (3) risk factors for total complications between patients who have SVI < 0.50 and SVI ≥ 0.50 who had a total knee arthroplasty (TKA). METHODS: Patients who underwent TKA between January 1, 2022 and December 31, 2022 were identified in the state of Maryland. A total of 4,952 patients who had complete social determinants of health data were included. Patients were divided into 2 cohorts according to SVI: < 0.50 (n = 2,431) and ≥ 0.50 (n = 2,521) based on the national mean SVI of 0.50. The SVI identifies communities that may need support caused by external stresses on human health based on 4 themed scores: socioeconomic status, household composition and disability, minority status and language, and housing and transportation. The SVI theme of household composition and disability encompassed patients aged 65 years and more, patients aged 17 years and less, civilians who have a disability, single-parent households, and English language deficiencies. The higher the SVI, the more social vulnerability or resources are needed to thrive in a geographic area. RESULTS: When controlling for risk factors and patient comorbidities, the theme of household composition and disability (odds ratio 2.0, 95% confidence interval 1.1 to 5.0, P = .03) was the only independent risk factor for total complications. Patients who had an SVI ≥0.50 were more likely to be women (65.8% versus 61.0%, P < .001), Black (34.4% versus 12.9%, P < .001), and have a median household income < $87,999 (21.3% versus 10.2%, P < .001) in comparison to the patients who had an SVI < 0.50, respectively. CONCLUSIONS: The SVI theme of household composition and disability, encompassing patients aged 65 years and more, patients aged 17 years and less, civilians who have a disability, single-parent households, and English language deficiencies, were independent risk factors for total complications following TKA. Together, these findings offer opportunities for interventions with selected patients to address social disparities.

Use and Application of Large Language Models for Patient Questions Following Total Knee Arthroplasty.

BACKGROUND: A consumer-focused health care model not only allows unprecedented access to information, but equally warrants consideration of the appropriateness of providing accurate patient health information. Nurses play a large role in influencing patient satisfaction following total knee arthroplasty (TKA), but they come at a cost. A specific natural language artificial intelligence (AI) model, ChatGPT (Chat Generative Pre-trained Transformer), has accumulated over 100 million users within months of launching. As such, we aimed to compare: (1) orthopaedic surgeons' evaluation of the appropriateness of the answers to the most frequently asked patient questions after TKA; and (2) patients' comfort level in answering their postoperative questions by using answers provided by arthroplasty-trained nurses and ChatGPT. METHODS: We prospectively created 60 questions based on the most commonly asked patient questions following TKA. There were 3 fellowship-trained surgeons who assessed the answers provided by arthroplasty-trained nurses and ChatGPT-4 to each of the questions. The surgeons graded each set of responses based on clinical judgment as: (1) "appropriate," (2) "inappropriate" if the response contained inappropriate information, or (3) "unreliable," if the responses provided inconsistent content. Patients' comfort level and trust in AI were assessed using Research Electronic Data Capture (REDCap) hosted at our local hospital. RESULTS: The surgeons graded 44 out of 60 (73.3%) responses for the arthroplasty-trained nurses and 44 out of 60 (73.3%) for ChatGPT to be "appropriate." There were 4 responses graded "inappropriate" and one response graded "unreliable" provided by the nurses. For the ChatGPT response, there were 5 responses graded "inappropriate" and no responses graded "unreliable." There were 136 patients (53.8%) who were more comfortable with the answers provided by ChatGPT compared to 86 patients (34.0%) who preferred the answers from arthroplasty-trained nurses. Of the 253 patients, 233 (92.1%) were uncertain if they would trust AI to answer their postoperative questions. There were 127 patients (50.2%) who answered that if they knew the previous answer was provided by ChatGPT, their comfort level in trusting the answer would change. CONCLUSIONS: One potential use of ChatGPT can be found in providing appropriate answers to patient questions after TKA. At our institution, cost expenditures can potentially be minimized while maintaining patient satisfaction. Inevitably, successful implementation is dependent on the ability to provide information that is credible and in accordance with the objectives of both physicians and patients. LEVEL OF EVIDENCE: III.

A Comparison Between Polyethylene Exchange and Full Revision for Arthrofibrosis Following Total Knee Arthroplasty.

BACKGROUND: Arthrofibrosis is a debilitating postoperative complication and a major cause of patient dissatisfaction following total knee arthroplasty (TKA). There is no consensus regarding the optimal treatment for stiffness after TKA. For cases not amenable to manipulation under anesthesia (MUA), one component or full revision are both suitable options. In a value-based healthcare era, maximizing cost-effectiveness with optimized clinical outcomes for patients remains the ultimate goal. As such, we compared (1) Knee Injury and Osteoarthritis Outcome Scores for Joint Replacement (KOOS, JR), (2) range of motion (ROM), as well as (3) complication rates, including MUA and lysis of adhesions (LOA), between polyethylene exchange and full component revision for TKA arthrofibrosis. METHODS: Patients were queried from an institutional database who underwent revision TKA for arthrofibrosis between January 1, 2015, and April 31, 2021. There were 33 patients who underwent full revision and 16 patients who underwent polyethylene exchange. Demographics and baseline characteristics between the cohorts were analyzed. Postoperative outcomes included MUA, LOA, and re-revision rates as well as KOOS, JR, and extension and flexion ROM at a mean follow-up of 3.8 years. Baseline comorbidities, including age, body mass index, alcohol use, tobacco use, and diabetes, were comparable between the full revision and polyethylene exchange revision cohorts (P > .05). The one and full component revisions had similar preoperative KOOS, JR (43 versus 42, P = .85), and flexion (81 versus 82 degrees, P = .80) versus extension (11 versus 11 degrees, P = .87) ROM. RESULTS: The full component revision had higher KOOS, JR (65 versus 55, P = .04), and flexion (102 versus 92 degrees, P = .02), but similar extension (3 versus 3 degrees, P = .80) ROM at final follow-up compared to the polyethylene exchange revision, respectively. The MUA (18.2 versus 18.8%, P = .96) and LOA (2.0 versus 0.0%, P = .32) rates were similar between full component and polyethylene exchange revisions. There was one re-revision (3.0%) for the cohort of patients who initially underwent full revision. There were four full re-revisions (25.0%) and two polyethylene exchange re-revisions (12.5%) performed in the cohort of patients who initially underwent a polyethylene exchange revision. CONCLUSIONS: The full component revision for stiffness after TKA showed favorable KOOS, JR, ROM, and outcomes in comparison to the polyethylene exchange revision. While the optimal treatment for stiffness after TKA is without consensus, this study supports the use of the full component revision when applied to the institutional population at hand. It is imperative that homogeneity exists in preoperative definitions, preoperative baseline patient demographics, ROM and function levels, outcome measures, and preoperative indications, as well as the inclusion of clinical data that assesses complete exchange, single exchange, and tibial insert exchange.

Trends in Deep Vein Thrombosis Prophylaxis After Total Knee Arthroplasty: 2016 to 2021.

BACKGROUND: In 2011, the American Academy of Orthopaedic Surgeons released a consensus recommending venous thromboembolism (VTE) prophylaxis after total knee arthroplasty (TKA). The purpose of our study was to examine (1) incidences of postoperative complications, including pulmonary embolism (PE), deep vein thrombosis (DVT), and transfusion rates; (2) trends from 2016 to 2021 in VTE prophylaxis; and (3) independent risk factors for 90-day total complications following TKA between aspirin, enoxaparin, rivaroxaban, and warfarin. METHODS: Using a national, all-payer database from 2016 to 2021, we identified all patients who underwent primary TKA. Exclusions included all patients who had prescribed anticoagulants within 1 year prior to TKA, hypercoagulable states, and cancer. Data were collected on baseline demographics, including age, sex, diabetes, and a comorbidity index, in each of the VTE prophylaxis cohorts. Postoperative outcomes included rates of PE, DVT, and transfusion. Multivariable regressions were performed to determine independent risk factors for total complications at 90 days following TKA. RESULTS: From 2016 to 2021, aspirin was the most used anticoagulant (n = 62,054), followed by rivaroxaban (n = 26,426), enoxaparin (n = 20,980), and warfarin (n = 13,305). The cohort using warfarin had the highest incidences of PE (1.8%) and DVT (5.7%), while the cohort using aspirin had the lowest incidences of PE (0.6%) and DVT (1.6%). The rates of aspirin use increased the most from 2016 to 2021 (32.1% to 70.8%), while the rates of warfarin decreased the most (19.3% to 3.0%). Enoxaparin, rivaroxaban, and warfarin were independent risk factors for total complications at 90 days. CONCLUSIONS: An epidemiological analysis of VTE prophylaxis use from 2016 to 2021 shows an increase in aspirin following TKA compared to other anticoagulant cohorts in a nationally representative population. This approach provides more insight and a better understanding of anticoagulation trends over this time period in a nationally representative sample.

Cemented Versus Cementless Femoral Fixation for Total Hip Arthroplasty Following Osteoarthritis.

BACKGROUND: The mode of femoral fixation for primary total hip arthroplasty (THA) is undetermined, with reported outcomes favoring different fixation methods. This study aimed to compare postoperative complications between cemented and cementless fixation at 90 days, 1 year, and 2 years in patients aged 65 years of age and older undergoing THA for osteoarthritis. METHODS: Using an all-payer, national database, patients 65 years and older undergoing primary THA, either with cementless (n = 56,701) or cemented (n = 6,283) femoral fixation for osteoarthritis were identified. A 1:1 propensity-matched analysis for age, sex, comorbidity index, alcohol abuse, tobacco use, obesity, and diabetes was performed, resulting in n = 6,283 patients in each cohort. Postoperative outcomes, including postoperative periprosthetic joint infection, aseptic revision, surgical site infection, pulmonary embolism, venous thromboembolism, wound complications, dislocation, periprosthetic fracture, and aseptic loosening were assessed. RESULTS: The cemented cohort had higher rates of infection (4.5 versus 0.8%, odds ratio [OR] 5.9, 95% confidence interval [CI] 4.33 to 7.93, P < .001), aseptic revision (2.9 versus 2.0%, OR 1.47, 95% CI 1.17 to 1.85, P = .001), venous thromboembolism (1.8 versus 1.3%, OR 1.40, 95% CI 1.05 to 1.87, P < .001), and aseptic loosening (1.5 versus 0.7%, OR 2.31, 95% CI 1.60 to 3.32, P < .001) at 90-days. At 1 and 2 years, the cemented cohort had higher rates of infection, aseptic revision, and aseptic loosening (all P < .001). Rates of periprosthetic fracture were similar at all time points (all P < .001). CONCLUSIONS: Cemented fixation had higher rates of infection, aseptic loosening, and aseptic revision. This finding supports the current use of cementless fixation, but the ultimate decision regarding fixation type should be based on the proper optimization of the patient's comorbidities and bone quality.

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.

Methodological Assessment of the 100 Most-Cited Articles in Total Knee Arthroplasty in the Last Decade Compared to the All-Time List.

BACKGROUND: Recent advances in total knee arthroplasty (TKA) have been driven by a growing focus on evidence-based medicine. This transition is reflected in the critical appraisal of both, the quality of work and the potential impact on the orthopedic community. The purpose of our study was to (1) identify the top 100 most-cited articles in TKA in the last decade and from all-time, and (2) compare methodological rigor of the most-cited articles in TKA in the last decade to articles all-time by level of evidence. METHODS: The top 100 cited articles were recorded for manuscripts from the last decade, January 1, 2012 to December 31, 2022, and manuscripts from all-time for TKA. We collected authors, year of publication, journal of the article, country of origin of authors, article type (basic science article, clinical research article), level of evidence, methodological index for non-randomized studies score, physiotherapy evidence database scale, and citation density (total citations/years published). RESULTS: The largest number of studies for all-time TKA (53.0%) and decade TKA (42.0%) were Level III. The average methodological index for non-randomized studies score for comparative studies was 18.7 for all-time TKA and 20.7 for decade TKA (P < .001). The average physiotherapy evidence database score was 6.1 for all-time TKA and 8.1 for decade TKA (P > .05). The highest citation density for all-time TKA was 111 and for past decade was 63. The number of level II studies in TKA increased from 19.0% from all time to 38.0% from the last decade (P < .05). CONCLUSIONS: Our findings of improved methodologies over time reflect positive steps toward evidence-based practice in TKA. A continued focus on producing methodologically sound studies may guide evidence-based clinical decision-making.

Appropriateness of Frequently Asked Patient Questions Following Total Hip Arthroplasty From ChatGPT Compared to Arthroplasty-Trained Nurses.

BACKGROUND: The use of ChatGPT (Generative Pretrained Transformer), which is a natural language artificial intelligence model, has gained unparalleled attention with the accumulation of over 100 million users within months of launching. As such, we aimed to compare the following: 1) orthopaedic surgeons' evaluation of the appropriateness of the answers to the most frequently asked patient questions after total hip arthroplasty; and 2) patients' evaluation of ChatGPT and arthroplasty-trained nurses responses to answer their postoperative questions. METHODS: We prospectively created 60 questions to address the most commonly asked patient questions following total hip arthroplasty. We obtained answers from arthroplasty-trained nurses and from the ChatGPT-3.5 version for each of the questions. Surgeons graded each set of responses based on clinical judgment as 1) "appropriate," 2) "inappropriate" if the response contained inappropriate information, or 3) "unreliable" if the responses provided inconsistent content. Each patient was given a randomly selected question from the 60 aforementioned questions, with responses provided by ChatGPT and arthroplasty-trained nurses, using a Research Electronic Data Capture survey hosted at our local hospital. RESULTS: The 3 fellowship-trained surgeons graded 56 out of 60 (93.3%) responses for the arthroplasty-trained nurses and 57 out of 60 (95.0%) for ChatGPT to be "appropriate." There were 175 out of 252 (69.4%) patients who were more comfortable following the ChatGPT responses and 77 out of 252 (30.6%) who preferred arthroplasty-trained nurses' responses. However, 199 out of 252 patients (79.0%) responded that they were "uncertain" with regard to trusting AI to answer their postoperative questions. CONCLUSIONS: ChatGPT provided appropriate answers from a physician perspective. Patients were also more comfortable with the ChatGPT responses than those from arthroplasty-trained nurses. Inevitably, its successful implementation is dependent on its ability to provide credible information that is consistent with the goals of the physician and patient alike.

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.

Projected volume of primary total joint arthroplasty in the USA from 2019 to 2060.

INTRODUCTION: The global incidence of total joint arthroplasty (TJA) has consistently risen over time, and while various forecasts differ in magnitude, future projections suggest a continued increase in these procedures. Differences in future United States projections may arise from the modeling method selected, the nature of the national arthroplasty registry employed, or the representativeness of the specific hospital discharge records utilized. In addition, many models have not accounted for ambulatory surgery as well as all payer types. Therefore, to attempt to make a more accurate model, we utilized a national representative sample that included outpatient arthroplasties and all insurance types to predict the volumes of primary TJA in the USA from 2019 to 2060. METHODS: A national, all-payer database was queried. All patients who underwent primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) from January 1, 2010, to December 31, 2019, were identified using international classification of disease Ninth Revision (9) and Tenth Revision (10) codes and current procedure terminology codes. Absolute frequencies and incidence rates were calculated per 100,000 for both THA and TKA procedures, with 95% confidence intervals. Mean growth in absolute frequency and incidence rates were calculated for each procedure from 2010 to 2014, and 2010 to 2019, with 95% confidence intervals (CI). RESULTS: The overall increase in THA and TKA procedures are expected to grow + 10 and + 36%, respectively, using linear regressions and + 9 and + 37%, respectively. The most positive mean growth in procedure frequency occurred from 2010 to 2014 for THA (+ 24, 95% Confidence Interval (CI): + 21, + 27) and 2010-2019 for TKA (+ 11%, 95% CI: + 9, + 14). There positive trend patterns in incidence rate growth for both procedures, with similar 2010-2019 incidence rates + 6%) for THA (+ 3%, 95% CI: + 0, + 6%) and TKA (+ 3%, 95% CI: + 1%, + 6%). CONCLUSION: Utilizing a nationally representative database, we demonstrated that TJA procedures would continue with an increased growth pattern to 2060, though slightly decreased from the surge from 2014 to 2019. While this finding applies to the representativeness of the population at hand, the inclusion of outpatient arthroplasty and all payer types validates an approach that has not been undertaken in previous projection studies.

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.

Assessing social disparities in inpatient vs. outpatient arthroplasty: a in-state database analysis.

INTRODUCTION: Given the growing emphasis on patient outcomes, including postoperative complications, in total joint arthroplasty (TJA), investigating the rise of outpatient arthroplasty is warranted. Concerns exist over the safety of discharging patients home on the same day due to increased readmission and complication rates. However, psychological benefits and lower costs provide an incentive for outpatient arthroplasty. The influence of social determinants of health disparities on outpatient arthroplasty remains unexplored. One metric that assesses social disparities, including the following individual components: socioeconomic status, household composition, minority status, and housing and transportation, is the Social Vulnerability Index (SVI). As such, we aimed to compare: (1) mean overall SVI and mean SVI for each component and (2) risk factors for total complications between patients undergoing inpatient and outpatient arthroplasty. METHODS: Patients who underwent TJA between January 1, 2022 and December 31, 2022 were identified. Data were drawn from the Maryland State Inpatient Database (SID). A total of 7817 patients had TJA within this time period. Patients were divided into inpatient arthroplasty (n = 1429) and outpatient arthroplasty (n = 6338). The mean SVI was compared between inpatient and outpatient procedures for each themed score. The SVI identifies communities that may need support cause by external stresses on human health based on four themed scores: socioeconomic status; household composition and disability; minority status and language; and housing and transportation. The SVI uses the United States Census data to rank census tracts for each individual theme, as well as an overall social vulnerability score. The higher the SVI, the more social vulnerability, or resources needed to thrive in that area. Multivariate logistic regression analyses were performed to identify independent risk factors for total complications following TJA after controlling for risk factors and patient comorbidities. Total complications included: infection, aseptic loosening, dislocation, arthrofibrosis, mechanical complication, pain, and periprosthetic fracture. RESULTS: Patients who had inpatient arthroplasty had higher overall SVI scores (0.45 vs. 0.42, P < 0.001). The SVI scores were higher for patients who had inpatient arthroplasty for socioeconomic status (0.36 vs. 0.32, P < 0.001), minority status and language (0.76 vs. 0.74, P < 0.001), and housing and transportation (0.53 vs. 0.50, P < 0.001) compared to outpatient arthroplasty, respectively. There was no difference between inpatient and outpatient arthroplasty for household composition and disability (0.41 vs. 0.41, P = 0.99). When controlling for comorbidities, inpatient arthroplasty [Odds Ratio (OR) 1.91, 95% Confidence Interval (CI) 1.23-2.95, P = 0.004], hypertension (OR 2.11, 95% CI 1.23-3.62, P = 0.007), and housing and transportation (OR 2.00, 95% CI 1.17-3.42, P = 0.012) were independent risk factors for total complications. CONCLUSION: Inpatient arthroplasty was associated with increased social disparities across several components of deprivation as well as an independent risk factor total complications following TJA. To the best of our knowledge, this study is the first to examine the negative repercussions of inpatient arthroplasty through the lens of social disparities and can target specific areas for intervention.

Neighborhood socioeconomic disadvantages associated with increased rates of revisions, readmissions, and complications after total joint arthroplasty.

INTRODUCTION: Low socioeconomic status based on neighborhood of residence has been suggested to be associated with poor outcomes after total joint arthroplasty (TJA). The area deprivation index (ADI) is a scale that ranks (zero to 100) neighborhoods by increasing socioeconomic disadvantage and accounts for median income, housing type, and family structure. We sought to examine the potential differences between high (national median ADI = 47) and low ADI among TJA recipients at a single institution. Specifically, we assessed: (1) 30-day emergency department visits/readmissions; (2) 90-day and 1-year revisions; as well as (3) medical and surgical complications. METHODS: A consecutive series of primary TJAs from September 21, 2015, through December 29, 2021, at a tertiary healthcare system were reviewed. A total of 3,024 patients who had complete ADI data were included. Patients were divided into groups below the national median ADI of 47 (n = 1,896) and above (n = 1,128). Multivariable regressions to determine independent risk factors accounting for ADI, race, age, sex, American Society of Anesthesiologists Classification grade, body mass index, diabetes, congestive heart failure (CHF), chronic obstructive pulmonary disease, hypertension, chronic kidney disease, alcohol abuse, substance abuse, and tobacco use. The primary outcomes of interest include evaluation of the independent association of ADI with total postoperative complications (at 30 days, 90 days, and 1 year) after adjusting for multiple relevant cofactors. RESULTS: After adjusting for multiple relevant cofactors, at 90 days, ADI > 47 (OR, 1.36, 95% CI 1.00-1.83, P = 0.04), men versus women (OR, 0.73, 95% CI 0.54-0.99, P = 0.039), and CHF (OR, 1.90, 95% CI 1.18-3.06, P = 0.009) were independently associated with increased total complications. The ADI was not associated with increased total complications at 30 days or 1-year (All P > 0.05). CONCLUSION: Our findings of higher complications of the ADI > 47 cohort at 90 days, reaffirm the complex relationship between ADI, patient demographics, and additional socioeconomic parameters that may influence postoperative outcomes and complications after TJA. This study utilizing ADI demonstrates potential areas of intervention and further investigation for assessing arthroplasty outcomes.

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.