Total Knee Arthroplasty Utilization Research Articles

Association between immigration status and total knee arthroplasty outcomes in Ontario, Canada: a population-based matched cohort study.

Immigrants and refugees face unique challenges navigating the health care system to manage severe arthritis, because of unfamiliarity, lack of awareness of surgical options, or access. The purpose of this study was to assess total knee arthroplasty (TKA) uptake, surgical outcomes, and hospital utilization among immigrants and refugees compared with Canadian-born patients. We included all adults undergoing primary TKA from January 2011 to December 2020 in Ontario. Cohorts were defined as Canadian-born or immigrants and refugees. We assessed change in yearly TKA utilization for trend. We compared differences in 1-year revision, infection rates, 30-day venous thromboembolism (VTE), presentation to emergency department, and hospital readmission between matched Canadian-born and immigrant and refugee groups. We included 158 031 TKA procedures. A total of 11 973 (7.6%) patients were in the immigrant and refugee group, and 146 058 (92.4%) patients were in the Canadian-born group. The proportion of TKAs in Ontario performed among immigrants and refugees nearly doubled over the 10-year study period (p < 0.001). After matching, immigrants were at relatively lower risk of 1-year revision (0.9% v. 1.6%, p < 0.001), infection (p < 0.001), death (p = 0.004), and surgical complications (p < 0.001). No differences were observed in rates of 30-day VTE or length of hospital stay. Immigrants were more likely to be discharged to rehabilitation (p < 0.001) and less likely to present to the emergency department (p < 0.001) than Canadian-born patients. Compared with Canadian-born patients, immigrants and refugees have favourable surgical outcomes and similar rates of resource utilization after TKA. We observed an underutilization of these procedures in Ontario relative to their proportion of the population. This may reflect differences in perceptions of chronic pain or barriers accessing arthroplasty.

The Cost-Effectiveness of Computer-Assisted Compared with Conventional Total Knee Arthroplasty: A Payer's Perspective.

Recent evidence showing that computer-assisted total knee arthroplasty (TKA) is associated with better outcomes compared with conventional TKA for patients with end-stage knee osteoarthritis has not been included in economic evaluations of computer-assisted TKA, which are needed to support coverage decisions. This study evaluated the cost-effectiveness of computer-assisted TKA from a payer's perspective, incorporating recent evidence. We compared computer-assisted TKA with conventional TKA with regard to costs (in 2022 U.S. dollars) and quality-adjusted life-years (QALYs) using Markov models for elderly patients (≥65 years of age) and patients who were not elderly (55 to 64 years of age). Costs and QALYs were estimated in the lifetime for elderly patients and in the short term for patients who were not elderly, under a bundled payment program and a Fee-for-Service program. Transition probabilities, costs, and QALYs were retrieved from the literature, a national knee arthroplasty registry, and the National Center for Health Statistics. Threshold and probabilistic sensitivity analyses were conducted to examine the robustness of key estimates used in the base-case analysis. Using projected estimates of TKA utilization, the total cost savings of performing computer-assisted TKA rather than conventional TKA were estimated. Compared with conventional TKA, computer-assisted TKA was associated with higher QALYs and lower costs for both elderly patients and patients who were not elderly, regardless of payment programs, making computer-assisted TKA a favorable treatment option. Widespread adoption of computer-assisted TKA in all U.S. patients would result in an estimated total cost saving of $1 billion for payers. Compared with conventional TKA, computer-assisted TKA reduces costs to payers while providing favorable outcomes. Payers may consider providing additional payment incentives to providers for performing computer-assisted TKA, to achieve outcome improvement and cost control by facilitating widespread adoption of computer-assisted TKA. Economic and Decision Analysis Level II. See Instructions for Authors for a complete description of levels of evidence.

Demographic and Socioeconomic Trends of Patients Undergoing Total Knee Arthroplasty From 2013 to 2022—An Analysis From an Urban Orthopaedic Hospital

BackgroundAs worldwide utilization of total knee arthroplasty (TKA) broadens, demographic trends can help make projections to inform access to care. This study aimed to assess the temporal trends in the socioeconomic and medical demographics of patients undergoing TKA. MethodsA retrospective review of 15,848 patients who underwent primary, elective TKA at an urban, New York City-based academic medical center between January 2013 and September 2022 was performed. Trends in patients’ age, body mass index (BMI), socioeconomic status (SES) (based on median income by patients’ ZIP code), race, and Charlson comorbidity index were evaluated using the Mann-Kendall test. ResultsIn the last decade, mean patient age (65 to 68 years, P < .001) and Charlson comorbidity index (1.4 to 2.3, P < .001) increased significantly. The proportion of patients who had a BMI ≥ 30 and < 40 increased (43.8 to 51.2%, P = .002), while the proportion of patients who had a BMI ≥ 40 (13.7 to 12.1%, P = .015) and BMI < 30 (42.5 to 36.8%, P = .020) decreased. The distribution of patients’ race and SES did not change from 2013 to 2022; Black (18.1 to 16.8%, P = .211) and low SES (12.9 to 11.3%, P = .283) patients consistently represented a minority of TKA patients. ConclusionsOver the last decade, the average age and comorbidity burden of TKA patients at our institution have increased. This portends the need for higher levels of preoperative optimization and postoperative management for TKA patients. A decreased prevalence of BMI ≥40 could reflect optimization efforts. However, the consistently low prevalence of Black and low-SES patients suggests that recent payment models did not improve access to care for these populations. Level of EvidenceIV.

Access to Total Knee Arthroplasty in Medicare Advantage Patients

Background: Total knee arthroplasty (TKA) is one of the most frequently performed procedures in Medicare patients in the United States. Among this population, enrollment in Medicare Advantage (MA) plans is rising but rates of elective TKA are 10-20% lower in MA health maintenance organization (HMO) plans compared to Traditional Medicare (TM). The purpose of this study was to evaluate the effect of Medicare type on patient access to TKA within the large population in Florida. Methods: The AAOS directory was queried for total joint surgeon practices within five Florida counties. Each office was called to assess the response to four insurance scenarios (Traditional Medicare, Blue Medicare Select PPO, Humana Gold Plus HMO, and commercial Cigna). Investigators used a Secret Shopper methodology with a standardized script to request a TKA. Data was gathered on insurance types accepted and number of business days to the next available appointment. Results: Of the 133 orthopaedics clinics called, 63 were accepting new TKA patients. Of those accepting new TKA patients, 91.7% accepted commercial Cigna, 96.8% accepted TM, 70.5% accepted MA HMO Humana Gold Plus, and 50.8% accepted MA PPO Blue Medicare Select. Compared to TM and commercial Cigna, both MA plans had significantly lower appointment success rates (all p&lt;.003). Time to earliest appointment did not significantly vary by insurance type or county (p&gt;.14). Conclusions: Patients in Florida with MA have decreased access to TKA compared to those with TM or commercial insurance, possibly explaining the lower rates of TKA utilization in the MA population.

Length of stay and inpatient charges of total knee arthroplasty in China: analysis of a national database.

There are limited data on the resource utilization of total knee arthroplasty (TKA) in China. This study aimed to examine the length of stay (LOS) and inpatient charges of TKA in China, and to investigate their determinants. We included patients undergoing primary TKA in the Hospital Quality Monitoring System in China between 2013 and 2019. LOS and inpatient charges were obtained, and their associated factors were further assessed using multivariable linear regression. A total of 184,363 TKAs were included. The LOS decreased from 10.8 days in 2013 to 9.3 days in 2019. The admission-to-surgery interval decreased from 4.6 to 4.2 days. The mean inpatient charges were 61,208.3 Chinese Yuan. Inpatient charges reached a peak in 2016, after which a gradual decrease was observed. Implant and material charges accounted for a dominating percentage, but they exhibited a downward trend, whereas labor-related charges gradually increased. Single marital status, non-osteoarthritis indication, and comorbidity were associated with longer LOS and higher inpatient charges. Female sex and younger age were associated with higher inpatient charges. There were apparent varieties of LOS and inpatient charges among provincial or non-provincial hospitals, hospitals with various TKA volume, or in different geographic regions. The LOS following TKA in China appeared to be long, but it was shortened during the time period of 2013 to 2019. The inpatient charges dominated by implant and material charges exhibited a downward trend. However, there were apparent sociodemographic and hospital-related discrepancies of resource utilization. The observed statistics can lead to more efficient resource utilization of TKA in China.

Utilization of Total Joint Arthroplasty by Rural-Urban Designation in Patients With Osteoarthritis in a Universal Coverage System

BackgroundUtilization of total joint arthroplasty (TJA) is affected by differences linked to sex, race, and socioeconomic status; there is little information about how geographic variation contributes to these differences. We sought to determine whether discrepancies in TJA utilization exist in patients diagnosed with osteoarthritis (OA) based upon urban-rural designation in a universal coverage system. MethodsWe conducted a cohort study using data from a US-integrated healthcare system (2015 to 2019). Patients aged ≥50 years who had a diagnosis of hip or knee OA were included. Total hip arthroplasty and total knee arthroplasty utilization (in respective OA cohorts) was evaluated by urban-rural designation (urban, mid, and rural). Incidence rate ratios (IRRs) for urban-rural regions were modeled using multivariable Poisson regressions. ResultsThe study cohort included 93,642 patients who have hip OA and 275,967 patients who had knee OA. In adjusted analysis, utilization of primary total hip arthroplasty was lower in patients living in urban areas (IRR = 0.87, 95% confidence interval = 0.81 to 0.94) compared to patients in rural regions. Similarly, total knee arthroplasty was used at a lower rate in urban areas (IRR = 0.88, 95% confidence interval = 0.82 to 0.95) compared with rural regions. We found no differences in the hip and knee groups within the mid-region. ConclusionsIn hip and knee OA patients enrolled in a universal coverage system, we found patients living in urban areas had lower TJA utilization compared to patients living in rural areas. Further research is needed to determine how patient location contributes to differences in elective TJA utilization. Level of EvidenceIII.

Impact of social disadvantage among total knee arthroplasty places of service on procedural volume: a nationwide Medicare analysis.

As recent analyses have indicated that low-volume hospitals experience higher rates of complications following total knee arthroplasty (TKA), it remains important to evaluate how area deprivation index (ADI) of hospitals impacts the quantity of TKA performed. Our analysis sought to evaluate how the ADI of orthopedic surgeon's place of service influences TKA utilization. The Medicare Provider Utilization and Payment Data Public Use File (MPUP-PUF) was queried to identify claims between 2013 and 2019 associated with Healthcare Common Procedure Coding System (HCPCS) code 27447 (TKA). The MPUP-PUF file was linked with publicly available ADI information as well as information regarding each provider's practice location. The Mann-Kendall trend test was used to analyze significant differences in TKA volume between ADI quintiles and differences in TKA volume overall between the years 2013 and 2019. An adjusted multivariable linear regression analysis was conducted to evaluate how ADI, and practice-specific characteristics, influenced TKA utilization volume. When isolating by ADI quintiles, no significant changes in TKA volume were demonstrated for Quintile 4 (Kendall's τ = 0.524; p = 0.13) and Quintile 5 (Kendall's τ = 0.524; p = 0.13) between 2013 and 2019. However, a significant increase in TKA volume over the study period was observed in Quintile 1 (Kendall's τ = 0.714 p = 0.034), Quintile 2 (Kendall's τ = 0.714 p = 0.034), and Quintile 3 (Kendall's τ = 0.905 p = 0.007). The adjusted multivariable linear regression model demonstrated that each increase in ADI quintile was associated with significantly lower TKA utilization (β-estimate -1.16; 95% CI -2.04 to -0.29; p = 0.009). Our findings suggest that resource deprivation contributes to disparities in TKA utilization. With the ongoing recognition of how social and neighborhood-level deprivation may influence access to end-stage osteoarthritis care and related perioperative outcomes, the present study serves to encourage continued efforts at ensuring equity in orthopedic care.

Increased Risk of Hospital Readmissions and Implant-Related Complications in Patients Who Had a Recent History of Fragility Fracture: A Matched Cohort Analysis

BackgroundWith the increasing utilization of total knee arthroplasty (TKA) in a continually aging US population, the number of patients who have low bone mineral density who undergo TKA may concomitantly increase. This study aimed to assess the rates of short-term complications following TKA in patients who did and did not have a recent history of a prior fragility fracture. MethodsA matched retrospective cohort study analyzing 48,796 patients was performed using a national database to determine the impact of a preceding fragility fracture on rates of short-term complications following TKA. The rates of complications at 1 and 2 years post-TKA were analyzed using multivariate logistic regressions. ResultsPrior fragility fracture was associated with increased rates of 1-year hospital readmissions (hazard ratio = 1.30, 95% CI, 1.22-1.38), periprosthetic fractures (odds ratio [OR] = 2.72, 95% CI, 1.89-3.99), non–infection-related revisions (OR = 1.32, 95% CI, 1.09-1.60), secondary fragility fractures (OR = 4.62, 95% CI, 4.19-5.12), prosthesis dislocations (OR = 1.76, 95% CI, 1.22-2.56), prosthesis instabilities (OR = 1.64, 95% CI, 1.25-2.15), and periprosthetic infections (OR = 1.49, 95% CI, 1.29-1.71), with similar trends in implant-related complications also seen at the 2-year mark. Patients who filled a prescription for osteoporosis pharmacotherapy had clinically similar rates of these complications compared to those who did not. ConclusionSustaining a fragility fracture prior to TKA is associated with an increased risk of hospital readmission and significant implant-related postoperative complications, potentially increasing the morbidity and mortality of TKA in these patients.

Does distance from joint line influence complications after distal femur fractures in native and periprosthetic knees?

BackgroundDistal femur fractures are projected to increase in incidence secondary to an aging population and growing utilization of total knee arthroplasty. Surgical management is the standard of care, but optimal treatment for far distal fractures is still unclear. Our study investigates if there are distal femur fractures too distal to be treated with lateral locked plating in periprosthetic fractures. MethodsOne hundred and ten consecutive patients treated with locked plating for distal femur fractures around a total knee replacement were identified using CPT codes. Fractures were classified by length of the distal fracture segment and Su classification. Complications studied were nonunion, malunion, infection, further fracture related surgery, readmission within 90 days, and mortality within 1 year of surgery. Sixty six fractures met inclusion criteria of 180 days of follow-up or sustaining a complication prior to180 days. ResultsThe size of the distal fracture segment and Su classification did not correlate with increased complication rate in periprosthetic distal femur fractures. ConclusionsThere was no difference between complications following lateral locked plating of distal femur fractures based on the size of the distal fracture segment in periprosthetic fractures. Lateral locked plating is an effective treatment modality for these fractures regardless of how distal the fracture extends.

Socioeconomic Disparities in the Utilization of Total Knee Arthroplasty

BackgroundDespite strong evidence supporting the efficacy of total knee arthroplasty (TKA), studies have shown significant socioeconomic disparities regarding who ultimately undergoes TKA. The purpose of the current study is to evaluate socioeconomic factors affecting whether a patient undergoes TKA after a diagnosis of osteoarthritis. MethodsFrom 2011 to 2018, claims for adult patients diagnosed with knee osteoarthritis in the New York Statewide Planning and Research Cooperative System (SPARCS) database were analyzed. International Classification of Diseases (ICD), 9/10 CM codes were used to identify the initial diagnosis for each patient. ICD 9/10 PCS codes were used to identify subsequent TKA. Logistic regression analysis was performed to determine the effect of patient factors on the likelihood of having TKA. ResultsOf 313,794 osteoarthritis diagnoses, 33.3% proceeded to undergo TKA. Increased age (OR 1.007, P < .0001) and workers’ compensation relative to commercial insurance (OR 1.865, P < .0001) had increased odds of TKA. Compared to White race, Asian (OR 0.705, P < .0001), Black (OR 0.497, P < .0001), and “other” race (OR 0.563, P < .0001) had lower odds of TKA. Hispanic ethnicity (OR 0.597, P < .0001) had lower odds of surgery. Compared to commercial insurance, Medicare (OR 0.876, P < .0001), Medicaid (OR 0.452, P < .0001), self-pay (OR 0.523, P < .0001), and “other” insurance (OR 0.819, P < .0001) had lower odds of TKA. Increased social deprivation (OR 0.987, P < .0001) had lower odds of TKA. ConclusionTKA is associated with disparities among race, ethnicity, primary insurance, and social deprivation. Additional research is necessary to identify the cause of these disparities to improve equity in orthopedic care.

A Retrospective Analysis of 1,595 Cases: Comparing the Characteristics of Total Knee Arthroplasty between Tibetans Living in the Plateau and Han of the Sichuan Basin.

Background Total knee arthroplasty is an effective treatment for end-stage knee arthritis. Studies' date have shown that the demand for knee replacements continues to increase worldwide. Although racial disparities have been previously reported in the utilization of total knee arthroplasty in western countries, however, there are few similar studies in China. Objectives Retrospective analysis of medical records identified the characteristics of Tibetan patients who had undergone total knee arthroplasty living in plateau and their differences with Hans living in Sichuan Basin. Methods The patients with unilateral primary total knee arthroplasty in Sichuan Orthopedic Hospital from 2015 to 2020 were enrolled. Analyze and compare the demographic characteristics (age, body mass index, and occupation) and pathogenesis characteristics (disease duration, exacerbation period, treatment methods, etc.) of the plateau Tibetans and the Hans of the Sichuan Basin. Results 1595 eligible patients were reviewed, including 541 Tibetan patients and 1054 Han patients, The average age of Tibetan patients was lower than that of Han patients (P < 0.001); the average BMI index of Tibetan patients was higher than that of Han patients (P < 0.001). And obese people account for more; the occupational distribution of Tibetan patients is more concentrated, mainly farmers. Tibetan patients have a longer course of disease than Han patients (P < 0.001). Conclusions The social background and geographical environment of the Tibetan population are different from those of the Han. Tibetans living on plateaus have an earlier illness, a longer course of illness, a more obvious trend of younger, age and fewer opportunities for regular treatment during the illness.

Outcomes and resource utilization in calcium pyrophosphate deposition disease patients who underwent total knee arthroplasty: a cross-sectional analysis.

This cross-sectional study aims to evaluate the predictors, outcomes, and resource utilization of total knee arthroplasty (TKA) in calcium pyrophosphate deposition disease (CPPD) patients. We used the US National Inpatient Sample database to identify CPPD and non-CPPD who underwent TKA from 2006 to 2014. Data collection included patient demographics and comorbidities. Outcomes following TKA included in-hospital mortality, complications, length of hospitalization, hospital charges, and disposition. Among the 5,564,005 patients who have undergone TKA, 11,529 (0.20%) had CPPD, with a median age of 72years, and 53.7% were females. Compared with non-CPPD, patients with CPPD were more likely to be older (mean 72 vs 66years; p < 0.001), male, white, and have Medicare insurance. CPPD patients were more likely to have ≥ 2 comorbidities calculated by the Charlson Comorbidity Index and discharge to an inpatient/rehabilitation facility. Regarding inpatient complications, myocardial infarction and knee reoperation were significantly more common in CPPD patients. TKA in CPPD patients was associated with significantly higher odds of increased length of stay (> 3days) than those without CPPD (OR 1.43, 95% CI 1.37-1.49). There was no significant difference in the in-hospital mortality even after adjusting for possible confounders. CPPD patients who underwent TKA were more likely to have a longer hospital stay and discharge to a non-home setting than non-CPPD. Also, CPPD patients had a higher comorbidity burden and risk for myocardial infarction and reoperation.Key Points• This is the largest study to analyze data of CPPD patients who underwent TKA and compare them with non-CPPD patients, using a large nationwide database.• Compared to non-CPPD patients, TKA in CPPD patients is associated with a greater length of stay and disposition to a nursing/rehabilitation facility.• In-hospital complications such as myocardial infarction and reoperation were more frequently observed in CPPD patients than non-CPPD.• The results of this study should alert healthcare providers to develop strategies in order to improve outcomes of CPPD patients undergoing TKA.

Racial and Socioeconomic Disparities in the Utilization of TKA Among Patients with Posttraumatic Knee Osteoarthritis: Estimates from the United States National Inpatient Sample, 2011-2018.

Background:Advanced posttraumatic osteoarthritis (PTOA) of the knee is a cause of substantial disability, particularly in younger individuals, and the treatment of choice is total knee arthroplasty (TKA). Racial and socioeconomic disparities exist in the use of TKA, but, to our knowledge, there have been no studies examining these disparities among patients with PTOA.Methods:We performed chi-square and logistic regression analyses on data from the Nationwide Inpatient Sample (NIS). The outcome of interest was the rate of TKA utilization, and the primary predictors were racial/ethnic group and insurance status. The regression models were adjusted for age, sex, household income, and Charlson Comorbidity Index (CCI).Results:The odds of receiving TKA for Black patients (odds ratio [OR] = 0.55; 95% confidence interval [CI], 0.48 to 0.62) and Hispanic patients (OR = 0.53; 95% CI, 0.46 to 0.62) were lower compared with White patients. Patients with Medicare (OR = 0.51; 95% CI, 0.46 to 0.57), those with Medicaid (OR = 0.48; 95% CI, 0.42 to 0.55), and those who self-paid (OR = 0.91, 95% CI: 0.14 to 0.25) had significantly lower odds of TKA compared with those with private insurance.Conclusions:Black and Hispanic patients are less likely than White patients to utilize TKA, and patients with private insurance are more likely to utilize TKA.Level of Evidence:Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Arthroplasty Rates Not Increasing in Young Patients With Rheumatoid Arthritis: A National Database Review, 2005 Versus 2014.

BackgroundFor 20 years, authors have predicted an expansion in total knee arthroplasty (TKA) and total hip arthroplasty (THA) utilization. Over this same period, the introduction of biological disease-modifying antirheumatic drugs has dramatically altered the treatment of rheumatoid arthritis (RA) with hopes of preventing articular damage and obviating the need for prosthetic replacement. The goal of our investigation was to evaluate TKA and THA utilization in young patients with RA (<65 years) in 2005 vs 2014 compared to patients with osteoarthritis (OA).MethodsUsing relevant International Classification of Disease Ninth Revision (ICD-9) and Current Procedural Terminology codes, the Truven MarketScan Database (over 46 million enrollees) was queried to determine THA and TKA incidence rates for RA and OA patients aged <65 years during the final decade of ICD-9 use. Patients with potentially confounding ICD-9 codes were excluded to limit coding variation. Statistical analysis consisted of student t-tests, Pearson's chi-square tests, and Breslow-Day tests.ResultsFor patients with OA, TKAs increased substantially from 0.07% in 2005 to 0.1% in 2014 (+42.9% change, P < .001). Similarly for patients with OA, THAs increased from 0.04% to 0.06% over the same time period (+66.0% change, P < .001). For young patients with RA, the rate of TKA remained relatively stable—1.06% in 2005 to 1.04% in 2014 (−1.7% change, P = .65)—as did THA—0.44% to 0.48% (+9.0% change, P = .14).ConclusionsDramatic increases in THA and TKA rates for OA patients aged <65 years were indeed observed from 2005 to 2014. This trend, however, was not seen in the RA population where TKA and THA rates remained unchanged.

Robotic total knee arthroplasty: A missed opportunity for cost savings in Bundled Payment for Care Improvement initiatives?

BackgroundThe use of robotic total knee arthroplasty has become increasingly prevalent. Proponents of robotic total knee arthroplasty tout its potential to not only improve outcomes, but also to reduce costs compared with traditional total knee arthroplasty. Despite its potential to deliver on the value proposition, whether robotic total knee arthroplasty has led to improved outcomes and cost savings within Medicare’s Bundled Payment for Care Improvement initiative remains unexplored. MethodsMedicare beneficiaries who underwent total knee arthroplasty designated under Medicare severity diagnosis related group 469 or 470 in the year 2017 were identified using the 100% Medicare Inpatient Standard Analytic Files. Hospitals participating in the Bundled Payment for Care Improvement were identified using the Bundled Payment for Care Improvement analytic file. We calculated risk-adjusted, price-standardized payments for the surgical episode from admission through 90-days postdischarge. Outcomes, utilization, and spending were assessed relative to variation between robotic and traditional total knee arthroplasty. ResultsOverall, 198,371 patients underwent total knee arthroplasty (traditional total knee arthroplasty: n= 194,020, 97.8% versus robotic total knee arthroplasty: n = 4,351, 2.2%). Among the 3,272 hospitals that performed total knee arthroplasty, only 300 (9.3%) performed robotic total knee arthroplasty. Among the 183 participating in the Bundled Payment for Care Improvement, only 40 (19%) hospitals performed robotic total knee arthroplasty. Risk-adjusted 90-day episode spending was $14,263 (95% confidence interval $14,231–$14,294) among patients who underwent traditional total knee arthroplasty versus $13,676 (95% confidence interval $13,467–$13,885) among patients who had robotic total knee arthroplasty. Patients who underwent robotic total knee arthroplasty had a shorter length of stay (traditional total knee arthroplasty: 2.3 days, 95% confidence interval: 2.3–2.3 versus robotic total knee arthroplasty: 1.9 days, 95% confidence interval: 1.9–2.0), as well as a lower incidence of complications (traditional total knee arthroplasty: 3.3%, 95% confidence interval: 3.2–3.3 versus robotic total knee arthroplasty: 2.7%, 95% confidence interval: 2.3–3.1). Of note, patients who underwent robotic total knee arthroplasty were less often discharged to a postacute care facility than patients who underwent traditional total knee arthroplasty (traditional total knee arthroplasty: 32.4%, 95% confidence interval: 32.3–32.5 versus robotic total knee arthroplasty: 16.8%, 95% confidence interval 16.1–17.6). Both Bundled Payment for Care Improvement and non-Bundled Payment for Care Improvement hospitals with greater than 50% robotic total knee arthroplasty utilization had lower spending per episode of care versus spending at hospitals with less than 50% robotic total knee arthroplasty utilization. ConclusionOverall 90-day episode spending for robotic total knee arthroplasty was lower than traditional total knee arthroplasty (Δ $–587, 95% confidence interval: $–798 to $–375). The decrease in spending was attributable to shorter length of stay, fewer complications, as well as lower utilization of postacute care facility. The cost savings associated with robotic total knee arthroplasty was only realized when robotic total knee arthroplasty volume surpassed 50% of all total knee arthroplasty volume. Hospitals participating in the Bundled Payment for Care Improvement may experience cost-saving with increased utilization of robotic total knee arthroplasty.

Increased Utilization of Total Joint Arthroplasty After Medicaid Expansion.

The expansion of state Medicaid programs under the U.S. Affordable Care Act has led to a dramatic increase in the number of Americans with health insurance coverage. Prior analyses of a limited number of states have suggested that greater utilization of total hip arthroplasty (THA) and total knee arthroplasty (TKA) should be expected after Medicaid expansion. The purpose of our study was to examine whether increased utilization of THA and TKA occurred across a broader range of states after Medicaid expansion. We analyzed administrative data from the Healthcare Cost and Utilization Project from 9 states (Arkansas, Arizona, Colorado, Iowa, Massachusetts, Maryland, Nevada, New York, and Vermont) that expanded Medicaid in 2014 and 2 states that did not expand Medicaid (Florida and Missouri). We included patients who were 18 to 64 years of age and had a primary THA or TKA from 2012 to 2015 with Medicaid as the primary payer. Other payers (including dual-eligible Medicaid and Medicare beneficiaries) were excluded. We performed multivariable regression modeling with the number of Medicaid-insured THAs or TKAs as the dependent variable and the interaction between the state Medicaid expansion status and year as the main policy independent variable, with adjustment for community characteristics. Among all 11 states, there were 39,452 total joint arthroplasties (42% THA and 58% TKA) funded by Medicaid from 2012 to 2015. After adjusting for community characteristics, within expansion states, compared with 2013, THA and TKA increased 15% in 2014 (p < 0.0001) and 23% in 2015 (p < 0.0001) within expansion states. Within non-expansion states, compared with 2013, there were significant utilization decreases of 18% in 2014 (p < 0.0001) and 11% in 2015 (p = 0.0002). Medicaid expansion was associated with significant increases in Medicaid-funded THA and TKA utilization in 9 states. As additional states consider expanding Medicaid programs and as alternative health reforms that increase insurance eligibility are debated, surgeons, administrators, and policymakers should prepare for a surge in the utilization of THA and TKA.

Time Trends in Perioperative Characteristics and Health Outcomes in Hispanic Patients Undergoing Primary Total Knee Arthroplasty.

This study analyzed the yearly trends in procedure utilization, comorbidity profiles, hospital length of stay (LOS), and 30-day outcomes in Hispanic/Latino patients undergoing primary total knee arthroplasty (TKA). Risk stratification for the development of postsurgical adverse events (AEs) was also investigated. The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) was queried for all Hispanic/Latino patients who underwent primary, elective TKA between 2011 and 2017. Thirty-day outcomes and risk factors were determined using multivariate models that controlled for baseline and perioperative differences. A total of 12,767 Hispanic/Latino patients were identified. Over the study period, the rate of TKA utilization increased by 108%. During the same time, there were significant reductions in the rates of COPD (1.9% vs. 2.9%, p = 0.015), anemia (18.0% vs. 23.5%, p < 0.001), dyspnea (2.9% vs. 4.0%, p = 0.006), and procedure length > 100min (35.2% vs. 39.4%, p < 0.001). Postoperatively, there was a significant decrease in LOS > 2days (41.3% vs. 75.6%, p < 0.001), but there was an increase in the rate of developing 30-day AEs (5.8% vs. 4.7%, p = 0.046). Independent risk factors for 30-day AEs included age > 65years, male sex, chronic steroid use, ASA > 2, diabetes, bleeding disorder, chronic kidney disease, and procedure length > 100min. While the recent trends in procedure utilization, comorbidity profiles, and LOS in Hispanic/Latino patients undergoing primary TKA are reassuring, these have not been accompanied with improved postoperative safety. Patients with bleeding disorders, chronic steroid use, and those admitted from facilities other than home appear to be at highest risk for developing 30-day AEs.

The implications of an aging population and increased obesity for knee arthroplasty rates in Sweden: a register-based study

Background and purpose — Total knee arthroplasty (TKA) has increased substantially in Sweden. We quantified the relative risk for TKA in the Swedish population for different BMI categories and age groups to investigate whether the continued increase in TKA is attributable to increased prevalence of obesity and elderly people in the population, and to put forward model predictions for coming needs for TKA. Patients and methods — We used the Swedish Nationwide Health Survey (SNHS) and the Swedish Knee Arthroplasty Register (SKAR) 2009–2015 to calculate the relative risk (RR) of TKA by age (middle-aged 45–64 years and elderly 65–84 years) and BMI (BMI 18.5–24.9 normal weight; BMI 25.0–29.9 overweight; BMI > 30 obese). The RR for TKA was applied to the demographic forecasts for the Swedish population as a forecasting model. Results — Population size increased 5.2% from 2009 to 2015 to 40,000 middle-aged and 250,000 elderly, and the prevalence of obesity increased from 16% to 18% in these 2 age categories. Compared with those of normal weight, the RR for TKA was 2.7 (95% CI 2.5–3.0) higher for the overweight and 7.3 (6.7–8.0) higher for the obese, aged 45–64. The corresponding figures for individuals aged 65–84 were 2.1 (2.0–2.2) and 4.0 (3.8–4.3) higher, respectively. The changes in the prevalence of obesity and an increase in the elderly population accounted for an estimated increase of 1,700 TKAs over the 7 years. Interpretation — The increase in obesity frequency and the rise in the population of middle-aged and elderly may, to some extent, explain the rise in TKA utilization in Sweden.

The Rise of Obesity among Total Knee Arthroplasty Patients.

In the United States, one-third of adults are considered obese, and demand for total knee arthroplasty (TKA) is expected to rise in these patients. Surgeons are reluctant to operate on obese patients, but it is important to understand how obesity has affected TKA utilization. This study utilizes a national database to evaluate incidence, demographics, outcomes, charges, and cost in nonobese, overweight, nonmorbidly obese, and morbidly obese TKA patients. We queried the National Inpatient Sample from 2009 to 2016 for primary TKA patients identifying 4,053,037 nonobese patients, 40,077 overweight patients, 809,649 nonmorbidly obese patients, and 428,647 morbidly obese patients. Chi-square was used to analyze categorical variables, and one-way analysis of variance was used to analyze continuous variables. Nonmorbidly obese and morbidly obese patients represented 23.2% of all TKAs. TKA utilization increased 4.1% for nonobese patients, 121.6% for overweight patients, 73.6% for nonmorbidly obese patients, and 83.9% for morbidly obese patients. Morbidly obese patients were younger (p < 0.001), female (p < 0.001), Black (p < 0.001), poor (p < 0.001), and utilized private insurance (p < 0.001). They also had the longest length of stay (p < 0.001) and the highest mortality rate (p < 0.001). More morbidly obese patients were discharged to other facilities (p < 0.001), and they had the highest rate of complications (p < 0.001). Patients with morbid obesity had the highest charges (p < 0.001), but overweight patients had the highest costs (p < 0.001). The results of this study demonstrate the rise in obese and morbidly obese patients seeking TKAs, which may be reflection of the obesity epidemic in America. Although TKA utilization has increased for morbidly obese patients, this body mass index (BMI) category also has the highest rates of charges and complications, suggesting morbid obesity to be a modifiable risk factor leading to worse surgical and economic outcomes. Obese patients undergoing TKA may benefit from preoperative optimization of their weight, in an effort to reduce the risk of adverse outcomes.

Racial and ethnic disparities in utilization of total knee arthroplasty among older women

To evaluate racial and ethnic disparities in utilization of total knee arthroplasty (TKA) in relation to demographic, health, and socioeconomic status variables. Prospective study of 102,767 Women's Health Initiative postmenopausal women initially aged 50-79, examining utilization rates of primary TKA between non-Hispanic Black/African American, non-Hispanic White, and Hispanic/Latina women (hereafter referred to as Black, White, and Hispanic). A total of 8,942 Black, 3,405 Hispanic, and 90,420 White women with linked Medicare claims data were followeduntil time of TKA, death, or transition from fee-for-service coverage. Absolute disparities were determined using utilization rates by racial/ethnic group and relative disparities quantified using multivariable hazards models in adjusting for age, arthritis, joint pain, mobility disability, body mass index, number of comorbidities, income, education, neighborhood socioeconomic status (SES), and geographic region. TKA utilization was higher among White women (10.7/1,000 person-years) compared to Black (8.5/1,000 person-years) and Hispanic women (7.6/1,000 person-years). Among women with health indicators for TKA including diagnosis of arthritis, moderate to severe joint pain, and mobility disability, Black and Hispanic women were significantly less likely to undergo TKA after adjusting for age [Black: HR (95% confidence interval)=0.70 (0.63-0.79); Hispanic: HR=0.58 (0.44-0.77)]. Adjustment for SES modestly attenuated the measured disparity, but significant differences remained [Black: HR=0.75 (0.67-0.89); Hispanic: HR=0.65 (0.47-0.89)]. Compared to White women, Black and Hispanic women were significantly less likely to undergo TKA after considering need and appropriateness for TKA and SES. Further investigation into personal-level and provider-level factors that may explain these disparities is warranted.