Association of the Comprehensive Care for Joint Replacement Model With Disparities in the Use of Total Hip and Total Knee Replacement.

Importance: The Comprehensive Care for Joint Replacement (CJR) model is Medicare's mandatory bundled payment reform to improve quality and spending for beneficiaries who need total hip replacement (THR) or total knee replacement (TKR), yet it does not account for sociodemographic risk factors such as race/ethnicity and income. Results of this study could be the basis for a Medicare payment reform that addresses inequities in joint replacement care. Objective: To examine the association of the CJR model with racial/ethnic and socioeconomic disparities in the use of elective THR and TKR among older Medicare beneficiaries after accounting for the population of patients who were at risk or eligible for these surgical procedures. Design, Setting, and Participants: This cohort study used the 2013 to 2017 national Medicare data and multivariable logistic regressions with triple-differences estimation. Medicare beneficiaries who were aged 65 to 99 years, entitled to Medicare, alive at the end of the calendar year, and residing either in the 67 metropolitan statistical areas (MSAs) mandated to participate in the CJR model or in the 104 control MSAs were identified. A subset of Medicare beneficiaries with a diagnosis of arthritis underwent THR or TKR. Data were analyzed from March to December 2020. Exposures: Implementation of the CJR model in 2016. Main Outcomes and Measures: Outcomes were separate binary indicators for whether a beneficiary underwent THR or TKR. Key independent variables were MSA treatment status, pre- or post-CJR model implementation phase, combination of race/ethnicity (non-Hispanic White, non-Hispanic Black, and Hispanic beneficiaries) and dual eligibility, and their interactions. Logistic regression models were used to control for patient characteristics, MSA fixed effects, and time trends. Results: The 2013 cohort included 4 447 205 Medicare beneficiaries, of which 2 025 357 (45.5%) resided in MSAs with the CJR model. The cohort's mean (SD) age was 77.18 (7.95) years, and it was composed of 2 951 140 female (66.4%), 3 928 432 non-Hispanic White (88.3%), and 657 073 dually eligible (14.8%) beneficiaries. Before the CJR model implementation, rates were highest among non-Hispanic White non-dual-eligible beneficiaries at 1.25% (95% CI, 1.24%-1.26%) for THR use and 2.28% (95% CI, 2.26%-2.29%) for TKR use in MSAs with CJR model. Compared with MSAs without the CJR model and the analogous race/ethnicity and dual-eligibility group, the CJR model was associated with a 0.10 (95% CI, 0.05-0.15; P < .001) percentage-point increase in TKR use for non-Hispanic White non-dual-eligible beneficiaries, a 0.11 (95% CI, 0.004-0.21; P = .04) percentage-point increase for non-Hispanic White dual-eligible beneficiaries, a 0.15 (95% CI, -0.29 to -0.01; P = .04) percentage-point decrease for non-Hispanic Black non-dual-eligible beneficiaries, and a 0.18 (95% CI, -0.34 to -0.01; P = .03) percentage-point decrease for non-Hispanic Black dual-eligible beneficiaries. These CJR model-associated changes in TKR use were 0.25 (95% CI, -0.40 to -0.10; P = .001) percentage points lower for non-Hispanic Black non-dual-eligible beneficiaries and 0.27 (95% CI, -0.45 to -0.10; P = .002) percentage points lower for non-Hispanic Black dual-eligible beneficiaries compared with the model-associated changes for non-Hispanic White non-dual-eligible beneficiaries. No association was found between the CJR model and a widening of the THR use gap among race/ethnicity and dual eligibility groups. Conclusions and Relevance: Results of this study indicate that the CJR model was associated with a modest increase in the already substantial difference in TKR use among non-Hispanic Black vs non-Hispanic White beneficiaries; no difference was found for THR. These findings support the widespread concern that payment reform has the potential to exacerbate disparities in access to joint replacement care.

Heterotopic Ossification Following Arthroplasty for Femoral Neck Fracture.

BACKGROUND: Heterotopic ossification (HO) is a frequent complication following hip surgery. Using data from the Hip Fracture Evaluation with Alternatives of Total Hip Arthroplasty versus Hemiarthroplasty (HEALTH) trial, we aimed to (1) determine the prevalence of HO following total hip arthroplasty (THA) for femoral neck fracture in patients ≥50 years of age, (2) identify whether HO is associated with an increased risk of revision surgery within 24 months after the fracture, and (3) determine the impact of HO on functional outcomes. METHODS: We performed a multivariable Cox regression analysis using revision surgery as the dependent variable and HO as the independent variable. We compared Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores between participants with and those without HO at 24 months. RESULTS: Of 1,441 participants in the study, 287 (19.9%) developed HO within 24 months. HO was not associated with subsequent revision surgery. Grade-III HO was associated with statistically significant and clinically relevant deterioration in the total WOMAC score, which was mainly related to the function component of the score, compared with grade I or II. CONCLUSIONS: The impact of grade-III HO on the functional outcomes and quality of life after THA for hip fracture is clinically important, and HO prophylaxis for selected high-risk patients may be appropriate. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Assessment of Extractability and Accuracy of Electronic Health Record Data for Joint Implant Registries.

Importance: Implant registries provide valuable information on the performance of implants in a real-world setting, yet they have traditionally been expensive to establish and maintain. Electronic health records (EHRs) are widely used and may include the information needed to generate clinically meaningful reports similar to a formal implant registry. Objectives: To quantify the extractability and accuracy of registry-relevant data from the EHR and to assess the ability of these data to track trends in implant use and the durability of implants (hereafter referred to as implant survivorship), using data stored since 2000 in the EHR of the largest integrated health care system in the United States. Design, Setting, and Participants: Retrospective cohort study of a large EHR of veterans who had 45 351 total hip arthroplasty procedures in Veterans Health Administration hospitals from 2000 to 2017. Data analysis was performed from January 1, 2000, to December 31, 2017. Exposures: Total hip arthroplasty. Main Outcomes and Measures: Number of total hip arthroplasty procedures extracted from the EHR, trends in implant use, and relative survivorship of implants. Results: A total of 45 351 total hip arthroplasty procedures were identified from 2000 to 2017 with 192 805 implant parts. Data completeness improved over the time. After 2014, 85% of prosthetic heads, 91% of shells, 81% of stems, and 85% of liners used in the Veterans Health Administration health care system were identified by part number. Revision burden and trends in metal vs ceramic prosthetic femoral head use were found to reflect data from the American Joint Replacement Registry. Recalled implants were obvious negative outliers in implant survivorship using Kaplan-Meier curves. Conclusions and Relevance: Although loss to follow-up remains a challenge that requires additional attention to improve the quantitative nature of calculated implant survivorship, we conclude that data collected during routine clinical care and stored in the EHR of a large health system over 18 years were sufficient to provide clinically meaningful data on trends in implant use and to identify poor implants that were subsequently recalled. This automated approach was low cost and had no reporting burden. This low-cost, low-overhead method to assess implant use and performance within a large health care setting may be useful to internal quality assurance programs and, on a larger scale, to postmarket surveillance of implant performance.

Association of Medicare Mandatory Bundled Payment System for Hip and Knee Joint Replacement With Racial/Ethnic Difference in Joint Replacement Care.

Importance: There are marked racial/ethnic differences in hip and knee joint replacement care as well as concerns that value-based payments may exacerbate existing racial/ethnic disparities in care. Objective: To examine changes in joint replacement care associated with Medicare's Comprehensive Care for Joint Replacement (CJR) model among White, Black, and Hispanic patients. Design, Setting, and Participants: Retrospective cohort study of Medicare claims from 2013 through 2017 among White, Black, and Hispanic patients undergoing joint replacement in 67 treatment (selected for CJR participation) and 103 control metropolitan statistical areas. Exposures: The CJR model holds hospitals accountable for spending and quality of joint replacement care during care episodes (index hospitalization through 90 days after discharge). Main Outcomes and Measures: The primary outcomes were spending, discharge to institutional postacute care, and readmission during care episodes. Results: Among 688 346 patients, 442 163 (64.2%) were women, and 87 286 (12.7%) were 85 years or older. Under CJR, spending decreased by $439 for White patients (95% CI, -$718 to -$161; from pre-CJR spending in treatment metropolitan statistical areas of $25 264) but did not change for Black patients and Hispanic patients. Discharges to institutional postacute care decreased for all groups (-2.5 percentage points; 95% CI, -4.7 to -0.4, from pre-CJR risk of 46.2% for White patients; -6.0 percentage points; 95% CI, -9.8 to -2.2, from pre-CJR risk of 59.5% for Black patients; and -4.3 percentage points; 95% CI, -7.6 to -1.0, from pre-CJR risk of 54.3% for Hispanic patients). Readmission risk decreased for Black patients by 3.1 percentage points (95% CI, -5.9 to -0.4, from pre-CJR risk of 21.8%) and did not change for White patients and Hispanic patients. Under CJR, Black-White differences in discharges to institutional postacute care decreased by 3.4 percentage points (95% CI, -6.4 to -0.5, from the pre-CJR Black-White difference of 13.3 percentage points). No evidence was found demonstrating that Black-White differences changed for other outcomes or that Hispanic-White differences changed for any outcomes under CJR. Conclusions and Relevance: In this cohort study of patients receiving joint replacements, CJR was associated with decreased readmissions for Black patients. Furthermore, Black patients experienced a greater decrease in discharges to institutional postacute care relative to White patients, representing relative improvements despite concerns that value-based payment models may exacerbate existing disparities. Nonetheless, differences between White and Black patients in joint replacement care still persisted even after these changes.

Can vertically integrated health systems provide greater value: The case of hospitals under the comprehensive care for joint replacement model?

OBJECTIVE: We aim to assess whether system providers perform better than nonsystem providers under an alternative payment model that incentivizes high-quality, cost-efficient care. We posit that the payment environment and the incentives it provides can affect the relative performance of vertically integrated health systems. To examine this potential influence, we compare system and nonsystem hospitals participating in Medicare's Comprehensive Care for Joint Replacement (CJR) model. DATA SOURCES: We used hospital cost and quality data from the Centers for Medicare & Medicaid Services linked to data from the Agency for Healthcare Research and Quality's Compendium of US Health Systems and hospital characteristics from secondary sources. The data include 706 hospitals in 67 metropolitan areas. STUDY DESIGN: We estimated regressions that compared system and nonsystem hospitals' 2017 cost and quality performance providing lower joint replacements among hospitals required to participate in CJR. PRINCIPAL FINDINGS: Among CJR hospitals, system hospitals that provided comprehensive services in their local market had 5.8 percent ($1612) lower episode costs (P = .01) than nonsystem hospitals. System hospitals that did not provide such services had 3.5 percent ($967) lower episode costs (P = .14). Quality differences between system hospitals and nonsystem hospitals were mostly small and statistically insignificant. CONCLUSIONS: When operating under alternative payment model incentives, vertical integration may enable hospitals to lower costs with similar quality scores.

The necessity of routine postoperative laboratory tests in enhanced recovery after surgery for primary hip and knee arthroplasty: A retrospective cohort study protocol.

INTRODUCTION: Over the last few decades, the concepts of minimally invasive surgery and enhanced recovery after surgery (ERAS) protocols have been introduced into the field of total joint arthroplasty (TJA), and tranexamic acid (TXA) has been widely used in TJA. Modern-day surgical techniques and perioperative care pathways of TJA have experienced unexpected improvements. Recently, the necessity of the practice of ordering routine postoperative laboratory tests for patients undergoing primary TJA has been challenged, especially in the context of implementation of ERAS protocols in TJA. These studies have consistently suggested that routine postoperative laboratory tests are not necessary in modern-day primary, unilateral total hip arthroplasty (THA) or total knee arthroplasty (TKA), and laboratory tests after surgery should only be obtained for patients with risk factors. However, it remains unclear whether routine postoperative laboratory tests after THA and TKA remains justified in the Chinese patient population. Therefore, we developed this study to address this issue. METHODS AND ANALYSIS: This retrospective cohort study will include adult patients who underwent primary unilateral THA or TKA and received multimodal perioperative care pathways according to ERAS protocols. The following patient data will be collected from the electronic medical record system: patients' demographics, preoperative and postoperative laboratory values, operation time, intraoperative blood loss, TXA use, tourniquet use, postoperative length of stay, and any medical intervention directly related to abnormal laboratory values. The main study outcomes are the incidence of acute anemia requiring transfusion and incidence of hypoalbuminemia requiring albumin supplementation. The secondary outcomes are the rates of acute kidney injury, incidence of abnormal serum sodium level, incidence of abnormal serum potassium level, and incidence of abnormal serum calcium level. These clinical data will be analyzed to determine the incidence of abnormal postoperative laboratory values following primary unilateral THA and TKA; to clarify the frequency of any medical intervention directly related to abnormal postoperative laboratory values; and to identify risk factors that predispose patients to have abnormal postoperative laboratory results. STUDY REGISTRATION: Chinese Clinical Trial Registry (http://www.chictr.org.cn): ChiCTR1900020690.

Association of Type and Frequency of Postsurgery Care with Revision Surgery after Total Joint Replacement.

CONTEXT: Postmarket surveillance is limited in the ability to detect medical device problems. Electronic health records can provide real-time information that might help with device surveillance. Specifically, the frequency of postsurgery care might indicate early problems and determine high-risk patients requiring more active surveillance. OBJECTIVE: To evaluate whether intensity of postsurgery care is associated with revision risk after total joint arthroplasty (TJA). DESIGN: Using an integrated health care system's TJA registry, we identified primary TJA performed between April 2001 and July 2013 (22,953 knees and 9904 hips). Survival analyses evaluated the frequency of specific types of outpatient and inpatient utilization 0 to 90 and 91 to 180 days postoperatively and revision risk. MAIN OUTCOME MEASURES: Revision surgery occurring at least 6 months after primary TJA. RESULTS: Knee arthroplasty recipients with 3 or more outpatient orthopedic allied health/nurse visits within 90 days had a 2.2 times (95% confidence interval [CI] = 1.6-2.9) higher risk of revision within the first 2 years postoperatively and 10.1 times higher risk (95% CI = 7.6-13.3) after 2 years. Compared with hip arthroplasty recipients who had 0 to 3 visits, patients with 6 or more outpatient orthopedic office visits within 90 days had a 15.7 times (95% CI = 5.7-42.9) higher risk of revision. Similar results were observed for 91-day to 180-day visits. CONCLUSION: Future studies are needed to determine if more specific data on reasons for the higher frequency of outpatient visits can refine these findings and elicit more specific recommendations for TJA devices.

The Effects of Revision Total Hip Arthroplasty on Medicare Spending and Beneficiary Outcomes: Implications for the Comprehensive Care for Joint Replacement Model.

BACKGROUND: After the first year in the Comprehensive Care for Joint Replacement (CJR) model, hospitals must repay Medicare for spending above a target price. Hospitals are incentivized to reduce spending in a 90-day episode and generate internal cost savings through, for example, the use of lower-cost implants. METHODS: We used a Markov model to compare quality-adjusted life-years and lifetime costs of total hip arthroplasty, under Medicare fee-for-service (baseline) and under alternative revision rate assumptions (prospective CJR scenarios). Results were generated for 65-year-old and 75-year-old male and female Medicare beneficiaries using baseline spending and revision rates from Medicare claims. We estimated the impact of CJR on 90-day spending. We ran sensitivity analyses for revision rates. RESULTS: Under willingness-to-pay thresholds of $50,000, $100,000, and $150,000, the baseline scenario was more cost-effective than the CJR scenario for a 65-year-old male patient if the revision risk increases by at least 7% (95% confidence interval for CJR savings: 4%-22%), 5% (range, 3%-7%), or 3% (range, 1%-5%), respectively. For males aged 75 years and females, revision risk needs to increase by a greater percentage under CJR relative to baseline for Medicare fee-for-service to be more cost-effective. CONCLUSION: The CJR model holds great promise. However, it incentivizes hospitals to choose lower-cost implants and adopt newer technology more slowly, which could potentially increase revision rates and offset benefits of the program. Policy makers should monitor revision rates and consider changes to the CJR model to ensure beneficiary access to valuable technology.

CMS hospital readmission reduction program and anticoagulants received following a total hip and knee arthroplasty discharge.

OBJECTIVES: To assess association between 30 day readmission rate and treatment received after total hip and knee arthroplasty (THA/TKA) discharge (rivaroxaban vs. warfarin or non-anticoagulant). To subsequently model impact of increasing rivaroxaban use on the Hospital Readmission Reduction Program (HRRP) penalty, which was imposed on hospitals with excess 30 day readmissions after hospitalizations for selected conditions, including THA/TKA. METHODS: The US Truven Health MarketScan Medicare Supplemental database from 1 July 2010 to 30 April 2015 was used. A retrospective claims analysis was conducted to assess the risk of all-cause 30 day readmission among patients receiving either rivaroxaban or warfarin, or no anticoagulation following THA/TKA discharge. Simulations were performed to estimate the impact of post-discharge treatment on the HRRP penalty. RESULTS: The risk-adjusted all-cause 30 day readmission rates were 1.21% (95% confidence interval [95% CI]: 0.94%-1.49%), 1.41% (95% CI: 1.19%-1.58%) and 1.95% (95% CI: 1.81%-2.11%) for rivaroxaban, warfarin and non-anticoagulant cohorts, respectively. Using these rates, simulations illustrated that when switching patients from warfarin or non-anticoagulant to rivaroxaban, annual penalty per hospital would be reduced up to 67% or 88%, respectively. CONCLUSIONS: Rivaroxaban treatment post-THA/TKA discharge reduced the risk of 30 day readmission compared to non-anticoagulants. Simulations illustrated that increasing rivaroxaban use could decrease the HRRP penalty.

Reducing complications and overall healthcare costs of hip fracture management: a retrospective study on the application of a Diagnostic Therapeutic Pathway in the Cosenza General Hospital.

BACKGROUND: Diagnostic Therapeutic Pathways (DTPs) are multidisciplinary plans designed by each healthcare organization for a specific category of patients to reduce the variability of professional behaviors and to ensure greater safety and better overall healthcare outcomes. Hip fractures are a frequent traumatic injury, particularly in the elderly, and DTPs recommend early surgical intervention, often not done due to organizational challenges and bureaucracy. Medical conditions suggesting a delay are not frequent, however long waiting times not only increase the risk of complications and mortality, but also increase the number of diagnostic test and physician consultations. This study tried to understand the benefits of performing surgical intervention within 48 hours in terms of cost savings, reduction of complications and better overall outcomes. We performed statistical analyses on data gathered from 130 patients submitted to DTPs, and we evaluated the benefits obtained by operating within 48 hours in terms of resource saving (number of physician consultations, hospitalization days, etc.), reduction in complications reported in the literature. METHODS: About 40% of clinical records of femoral fractures from 2015 at the Cosenza General Hospital were used in our statistical analysis taking into account independent variables such as age, sex,surgery waiting times and ASA (e.g. American Society of Anesthesiologists) score. Additionally, dependent variables such as: the type of complications during the hospital stay (e.g. infections, delirium, etc), days of hospitalization, and number of physician consultations were considered. RESULTS: The average waiting time for surgical intervention was 5.48 days (132 hr). Patients with ASA score of 4 had a greater chance of complications (p-value 0.03), whereas patients operated within 48 hours avoided complications, and spent fewer days in the hospital. The ASA score value correlated positively with the number of physician consultation, as the ASA score increased in number, so did the number of physician consultations. Moreover, each additional day of waiting increased the possibility of physician consultation by approximately 13. CONCLUSION: The lack of available hospital beds and staff shortages are the main reasons for the delay in performing surgery, this situation does not allow an efficient treatment and timely release of patients from the healthcare system. Therefore, there is an important need to implement standardized orthopedic and geriatric pathways (DTPs), inspired by the collaboration between healthcare system management, orthopedic and geriatric specialists, and physical therapists, to drive shorter days of hospitalization and better overall patient health outcome by performing surgery as soon as possible.

Hip Fracture Does Not Belong in the Elective Arthroplasty Bundle: Presentation, Outcomes, and Service Utilization Differ in Fracture Arthroplasty Care.

BACKGROUND: Center for Medicare and Medicaid Services reimbursement is the same for hip arthroplasty performed electively for arthritis and urgently for femoral neck fracture. METHODS: An analytic report of hip arthroplasty for a 5-hospital network identified 2362 cases performed from January 2014 to May 2016. Resource utilization was determined using 90-day charges. RESULTS: The fracture population (623 hips) was older (P < .01), had more medical comorbidities (28.3% vs 3.8%, P < .01), and was more likely to be anemic and malnourished (P < .01), and had longer hospital stay (5.7 vs 3.0 days, P < .0001), more frequent intensive care unit admission (4.5% vs 0.5%, P < .01), less frequent discharge to home (16.2% vs 83.6%, P < .01), more emergency department visits (26.5% vs 10.7%, P < .01), and more readmissions after hospital discharge (25.2% vs 12.2%, P < .01). Utilization of services ($50,875 vs $38,705, P < .0001) and the standard deviation of these services ($22,509 vs $9,847, P < .0001), from 90-day charges, were significantly greater in the fracture population. CONCLUSION: This study supports exclusion of fracture care from the Comprehensive Care for Joint Replacement bundled payment program.

Kaiser Permanente: Joint Arthroplasty in an Integrated Capitated Care Delivery Model.

BACKGROUND: Total joint arthroplasty is a successful operation with increasing prevalence in the United States. Kaiser Permanente has been using multiple tools to optimize patient outcomes while keeping health-care expenditures in check. METHODS: We describe the patient, surgeon, and hospital perspective toward the delivery of sustainable arthroplasty care for a growing elderly population. Quality metrics for each stakeholder are presented. RESULTS: Kaiser Permanente optimizes value for the patient, surgeon, and hospital with the use of evidence-based integrated care pathways and a national joint arthroplasty registry. CONCLUSION: A continued focus on value-driven care will provide continued efficiency in a time of growth with maintenance of excellent outcomes.

Reasons for Ninety-Day Emergency Visits and Readmissions After Elective Total Joint Arthroplasty: Results From a US Integrated Healthcare System.

BACKGROUND: Previous studies evaluating reasons for 30-day readmissions following total joint arthroplasty (TJA) may underestimate hospital-based utilization of healthcare resources during a patient's episode-of-care. We sought to identify common reasons for 90-day emergency department (ED) visits and hospital readmissions following primary elective unilateral TJA. METHODS: Patients from July 1, 2012 through June 30, 2015 having primary elective TJA and at least one 90-day postoperative ED-only visit and/or readmission for any reason were identified using the Kaiser Permanente Total Joint Replacement Registry. Chart reviews for ED visits/readmissions included 13 surgical and 11 medical reasons. The 2344 total hips and 5520 total knees were analyzed separately. RESULTS: Incidence of at least one ED visit following total hip arthroplasty (THA) was 13.4% and 4.5% for readmissions. The most frequent reasons for ED visits were swelling (15.6%) and pain (12.8%); the most frequent reasons for readmissions were infection (12.5%) and unrelated elective procedures (9.0%). The incidence of at least one ED visit following total knee arthroplasty (TKA) was 13.8%, and the incidence of readmission was 5.5%. The most frequent reasons for ED visits were pain (15.8%) and swelling (15.6%); the most common readmission reasons were gastrointestinal (19.1%) and manipulation under anesthesia (9.4%). CONCLUSION: Swelling and pain related to the procedure were the most frequent reasons for 90-day ED visits after both THA and TKA. Readmissions were most commonly due to infection or unrelated procedures for THA and gastrointestinal or manipulation under anesthesia for TKA. Modifications to discharge protocols may help prevent or alleviate these issues, avoiding unnecessary hospital returns.

Regenerative therapies increase survivorship of avascular necrosis of the femoral head: a systematic review and meta-analysis.

PURPOSE: The aim of this study was to document the available evidence on the use of regenerative techniques for the treatment of femoral head osteonecrosis (or avascular necrosis of femoral head, AVN) and to understand their benefit compared to core decompression (CD) alone in avoiding failure and the need for total hip replacement (THR). METHODS: The search was conducted on three medical electronic databases according to PRISMA guidelines. The studies reporting number and timing of failures were included in a meta-analysis calculating cumulative survivorship with a Kaplan-Mayer curve. Moreover, the results on failures in treatment groups reported in RCT were compared with those documented in control groups, in order to understand the benefit of biological therapies compared to CD for the treatment of AVN. RESULTS: Forty-eight studies were included in this systematic review, reporting results of different types of regenerative techniques: mesenchymal stem cell implantation in the osteonecrotic area, intra-arterial infiltration with mesenchymal stem cells, implantation of bioactive molecules, or platelet-rich plasma. Overall, reported results were good, with a cumulative survivorship of 80% after ten year follow-up, and better results when regenerative treatments were combined to CD compared to CD alone (89.9% vs 70.6%, p < 0.0001). CONCLUSION: Regenerative therapies offer good clinical results for the treatment of AVN. The combination of CD with regenerative techniques provides a significant improvement in terms of survivorship over time compared with CD alone. Further studies are needed to identify the best procedure and the most suitable patients to benefit from regenerative treatments for AVN.

Association between Dairy Product Consumption and Incidence of Total Hip Arthroplasty for Osteoarthritis.

OBJECTIVE: The aim of this prospective cohort study was to determine whether dairy product consumption was associated with the incidence of total hip arthroplasty for osteoarthritis (OA). METHODS: There were 38,924 participants from the Melbourne Collaborative Cohort Study who had dairy product consumption recorded in 1990-1994. The incidence of total hip arthroplasty for OA during 2001-2013 was determined by linking cohort records to the Australian Orthopaedic Association National Joint Replacement Registry. RESULTS: Over an average of 11.8 years of followup, 1505 total hip arthroplasties for OA were identified (524 in men, 981 in women). In men, a 1 SD increase in dairy product consumption was associated with a 21% increased incidence of total hip arthroplasty for OA (HR 1.21, 95% CI 1.10-1.33), with a dose-response relationship observed for quartiles of dairy product consumption (p for trend = 0.001). These results were independent of age, body mass index, country of birth, education, smoking status, vigorous physical activity, calcium supplementation, energy consumption, circulating 25-hydroxy vitamin D, hypertension, and diabetes. No significant association was observed for women (HR 1.02, 95% CI 0.95-1.09). CONCLUSION: Increasing dairy product consumption was associated with an increased risk of total hip arthroplasty for men with OA, with no significant association observed for women. Understanding the mechanisms may help identify strategies to prevent hip OA, particularly for men.

Is Orthopedic Department Teaching Status Associated With Adverse Outcomes Of Primary Total Hip Arthroplasty?

BACKGROUND: Although resident physicians play a vital role in the US health care system, they are believed to create inefficiencies in the delivery of care. Under the regional component of the Comprehensive Care for Joint Replacement model, teaching hospitals are forced to compete on efficiency and outcomes with nonteaching hospitals. METHODS: We identified 86,021 patients undergoing elective primary total hip arthroplasty in New York State between January 1, 2009, and September 30, 2014. Outcomes included length and cost of the index admission, disposition, and 90-day readmission. Mixed-effects regression models compared teaching vs nonteaching orthopedic hospitals after adjusting for patient demographics, comorbidities, hospital, surgeon, and year of surgery. RESULTS: Patients undergoing surgery at teaching hospitals had longer lengths of stay (ß = 3.2%; P < .001) and higher costs of admission (ß = 13.6%; P < .001). There were no differences in disposition status (odds ratio = 1.03; P = .779). The risk of 90-day readmission was lower for teaching hospitals (odds ratio = 0.89; P = .001). CONCLUSION: Primary total hip arthroplasty at teaching orthopedic hospitals is characterized by greater utilization of health care resources during the index admission. This suggests that teaching hospitals may be adversely affected by reimbursement tied to competition on economic and clinical metrics. Although a certain level of inefficiency is inherent during the learning process, these policies may hinder learning opportunities for residents in the clinical setting.

Variation in Diagnoses for Hip Arthroplasty Among New York State Hospitals: Implications for the Comprehensive Care for Joint Replacement Model.

BACKGROUND: The Comprehensive Care for Joint Replacement model is designed to minimize costs and improve quality for Medicare patients undergoing joint arthroplasty. The cost of hip arthroplasty (HA) episode varies depending on the preoperative diagnosis and is greater for fracture than for osteoarthritis. Hospitals that perform a higher percentage of HA for OA may therefore have an advantage in the Comprehensive Care for Joint Replacement model. The purposes of this study are to (1) determine the variability in underlying diagnosis for HA in New York State hospitals, and (2) determine hospital characteristics, such as volume, associated with this. METHODS: The New York Statewide Planning and Research Cooperative System database was used to identify 127,206 primary HA procedures from 2010 to 2014. The data included underlying diagnoses, age, length of stay, and total charges. Hospitals were categorized by volume and descriptive statistics were used. RESULTS: OA was the underlying diagnosis for HA for 74.2% of all patients; this was significantly higher for high-volume (89.30%) and medium-volume (74.9%) hospitals than for low-volume hospitals (58.4%, P < .05). HA for fracture was significantly more common at low-volume hospitals (32.4%) compared to medium-volume (18.0%) and high-volume (4.7%) hospitals (P < .05). Length of stay was significantly greater at low-volume hospitals for all diagnoses. CONCLUSION: High-volume hospitals perform a higher ratio of HA cases for OA compared to fracture, which may lead to advantages in patient outcomes and cost. The variation in underlying diagnosis between hospitals has financial implications and underscores the need for HAs to be risk stratified by preoperative diagnosis.

The Association Between Hospital Length of Stay and 90-Day Readmission Risk Within a Total Joint Arthroplasty Bundled Payment Initiative.

BACKGROUND: To curb the unsustainable rise in health care expenses, health care payers are developing programs to incentivize hospitals and physicians to improve the value of care delivered to patients. Payers are utilizing various metrics, such as length of stay (LOS) and unplanned readmissions, to track progression of quality metrics. Relevant to orthopedic surgeons, the Centers for Medicare and Medicaid Services announced in 2015 the Comprehensive Care for Joint Replacement Payment Model-a program aimed at improving the quality of health care delivered to patients by shifting more of the financial risk of patient care onto providers. METHODS: We analyzed the medical records of 1329 consecutive lower extremity total joint patients enrolled in Centers for Medicare and Medicaid Services' Bundled Program for Care Improvement treated over a 21-month period. The goal of this study was to ascertain if hospital LOS is associated with unplanned readmissions within 90 days of admission for a total hip or knee arthroplasty. RESULTS: After controlling for multiple demographic variables including sex, age, comorbidities and discharge location, we found that hospital LOS greater than 4 days is a significant risk factor for unplanned readmission within 90 days (odd ratio = 1.928, P = .010). Total knee arthroplasty (TKA) and discharge to a location other than home are also independent risk factors for 90-day readmission. CONCLUSION: Our results demonstrate that increased LOS is a significant risk factor for readmission within 90 days of admission for a hip or knee arthroplasty in the Medicare population.

Alumina Delta-on-Highly Crosslinked-Remelted Polyethylene Bearing in Cementless Total Hip Arthroplasty in Patients Younger than 50 Years.

BACKGROUND: The purpose of this retrospective study was to determine the clinical and radiographic results, prevalence of polyethylene wear and osteolysis, and fracture of alumina delta ceramic femoral head or highly crosslinked, remelted polyethylene (HXLPE) liner associated with the use of alumina delta ceramic femoral head-on-HXLPE bearing in cementless total hip arthroplasty in patients younger than 50 years. METHODS: We reviewed the cases of 119 patients (130 hips) who underwent a cementless total hip arthroplasty using alumina delta ceramic-on-HXLPE bearing when they were 50 years or younger at the time of surgery. The most common diagnoses were osteonecrosis (51%) and osteoarthritis secondary to developmental dysplastic hip (39%). Osteolysis and polyethylene wear rates were evaluated with use of radiography and computed tomography. In addition, prevalence of fracture of alumina delta ceramic head and polyethylene line was documented. The mean follow-up was 8.3 years (range, 7-9 years). RESULTS: The mean Harris hip score, Western Ontario and McMaster Universities Osteoarthritis Index score, University of California, Los Angeles activity score were 94 points, 14 points, and 8.1 points, respectively, at the final follow-up. No patient had thigh pain. All acetabular components and all but one femoral components were well fixed. The mean annual penetration rate of femoral head was 0.022 ± 0.003 mm/year. No hip had osteolysis or ceramic head or HXLPE liner fracture. CONCLUSION: Our average 8.3-year results with the use of alumina delta ceramic-on-HXLPE bearing in the patients younger than 50 years suggest that cementless acetabular and femoral components provide a high survival rate without evidence of osteolysis or ceramic head or AXLPE liner fracture.

Quality of life following hip fractures: results from the Norwegian hip fracture register.

BACKGROUND: Patient-reported health-related quality of life is an important outcome measure when assessing the quality of hip fracture surgery. The frequently used EQ-5D index score has unfortunately important limitations. One alternative can be to assess the distribution of each of the five dimensions of the patients' descriptive health profile. The objective of this paper was to investigate health-related quality of life (HRQoL) after hip fractures. METHODS: Data from hip fracture operations from 2005 through 2012 were obtained from The Norwegian Hip Fracture Register. Patient reported HRQoL, (EQ-5D-3L) was collected from patients preoperatively and at four and twelve months postoperatively n = 10325. At each follow-up the distribution of the EQ-5D-3L and mean pain VAS was calculated. RESULTS: Generally, a higher proportion of patients reported problems in all 5 dimensions of the EQ-5D-3L at all follow-ups compared to preoperative. Also a high proportion of patients with no preoperative problems reported problems after surgery; At 4 and 12 months follow-ups 71 % and 58 % of the patients reported walking problems, and 65 % and 59 % of the patients reported pain respectively. Patients with femoral neck fractures and the youngest patients (age < 70 years) reported least problems both preoperatively and at all follow-ups. CONCLUSIONS: A hip fracture has a dramatic impact on the patients' HRQoL, and the deterioration in HRQoL sustained also one year after the fracture. Separate use of the descriptive profile of the EQ-5D is informative when assessing quality of life after hip fracture surgery.