Trends in the Adoption of Outpatient Joint Arthroplasties and Patient Risk: A Retrospective Analysis of 2019 to 2021 Medicare Claims Data.

INTRODUCTION: Total joint arthroplasties (TJAs) have recently been shifting toward outpatient arthroplasty. This study aims to explore recent trends in outpatient total joint arthroplasty (TJA) procedures and examine whether patients with a higher comorbidity burden are undergoing outpatient arthroplasty. METHODS: Medicare fee-for-service claims were screened for patients who underwent total hip, knee, or shoulder arthroplasty procedures between January 2019 and December 2022. The procedure was considered to be outpatient if the patient was discharged on the same date of the procedure. The Hierarchical Condition Category Score (HCC) and the Charlson Comorbidity Index (CCI) scores were used to assess patient comorbidity burden. Patient adverse outcomes included all-cause hospital readmission, mortality, and postoperative complications. Logistic regression analyses were used to evaluate if higher HCC/CCI scores were associated with adverse patient outcomes. RESULTS: A total of 69,520, 116,411, and 41,922 respective total knee, hip, and shoulder arthroplasties were identified, respectively. Despite earlier removal from the inpatient-only list, outpatient knee and hip surgical volume did not markedly increase until the pandemic started. By 2022Q4, 16%, 23%, and 36% of hip, knee, and shoulder arthroplasties were discharged on the same day of surgery, respectively. Both HCC and CCI risk scores in outpatients increased over time ( P < 0.001). DISCUSSION: TJA procedures are shifting toward outpatient surgery over time, largely driven by the COVID-19 pandemic. TJA outpatients' HCC and CCI risk scores increased over this same period, and additional research to determine the effects of this should be pursued. LEVEL OF EVIDENCE: Level III, therapeutic retrospective cohort study.

Scheduling and Vendor Consistency Improves Turnover Time Efficiency in Total Joint Arthroplasty.

BACKGROUND: Maximizing operative room (OR) efficiency is important for hospital efficiency, patient care, and positive surgeon and staff morale. Reducing turnover time (TOT) has become a popular focus to improve OR efficiency. The present study evaluated if TOT is influenced by changing case type, implant vendor, and/or laterality. METHODS: In total, 444 turnovers from January to July 2023 were retrospectively analyzed. All turnovers were same-surgeon turnovers between primary arthroplasty cases in dedicated, overlapping rooms. Single linear regression models tested the predictability of TOT based on case type, vendor, and laterality. A multivariate multiple regression and 1-way Analyses of Variance analyzed variables against each other. Independent sample t-tests evaluated TOTs when all variables were the same or different. RESULTS: Changing versus keeping the same case type increased TOT by 2.4 minutes (95% confidence interval [CI] = 0.7, 4.0; P = .004). Changing vendors increased TOT by 2.9 minutes (95% CI = 1.1, 4.7; P = .002). Laterality did not affect TOT, with a change of 0.9 minutes (95% CI = -0.6, 2.5; P = .229). Vendor (P = .030) independently predicted TOT when analyzed as a covariate with case type (P = .410). The TOT with same case type and vendor (mean 38.2 minutes; range, 22 to 62) was less than that of different case types and vendors (mean 41.4 minutes; range, 26 to 73) (P = .017). Mean TOT differed by 5.5 minutes when keeping all variables the same versus all different (P = .018). CONCLUSIONS: Maintaining a consistent case type, vendor, and laterality had a synergistic effect in reducing TOT in arthroplasty ORs with the same primary surgeon running 2 overlapping rooms. Changing vendor representatives was found to independently predict TOT increases, which is likely attributed to a disruption in workflow and collaboration of the multidisciplinary OR team. LEVEL OF EVIDENCE: Level III.

Trial of Vancomycin and Cefazolin as Surgical Prophylaxis in Arthroplasty.

BACKGROUND: The addition of vancomycin to beta-lactam prophylaxis in arthroplasty may reduce surgical-site infections; however, the efficacy and safety are unclear. METHODS: In this multicenter, double-blind, superiority, placebo-controlled trial, we randomly assigned adult patients without known methicillin-resistant Staphylococcus aureus (MRSA) colonization who were undergoing arthroplasty to receive 1.5 g of vancomycin or normal saline placebo, in addition to cefazolin prophylaxis. The primary outcome was surgical-site infection within 90 days after surgery. RESULTS: A total of 4239 patients underwent randomization. Among 4113 patients in the modified intention-to-treat population (2233 undergoing knee arthroplasty, 1850 undergoing hip arthroplasty, and 30 undergoing shoulder arthroplasty), surgical-site infections occurred in 91 of 2044 patients (4.5%) in the vancomycin group and in 72 of 2069 patients (3.5%) in the placebo group (relative risk, 1.28; 95% confidence interval [CI], 0.94 to 1.73; P = 0.11). Among patients undergoing knee arthroplasty, surgical-site infections occurred in 63 of 1109 patients (5.7%) in the vancomyin group and in 42 of 1124 patients (3.7%) in the placebo group (relative risk, 1.52; 95% CI, 1.04 to 2.23). Among patients undergoing hip arthroplasty, surgical-site infections occurred in 28 of 920 patients (3.0%) in the vancomyin group and in 29 of 930 patients (3.1%) in the placebo group (relative risk, 0.98; 95% CI, 0.59 to 1.63). Adverse events occurred in 35 of 2010 patients (1.7%) in the vancomycin group and in 35 of 2030 patients (1.7%) in the placebo group, including hypersensitivity reactions in 24 of 2010 patients (1.2%) and 11 of 2030 patients (0.5%), respectively (relative risk, 2.20; 95% CI, 1.08 to 4.49), and acute kidney injury in 42 of 2010 patients (2.1%) and 74 of 2030 patients (3.6%), respectively (relative risk, 0.57; 95% CI, 0.39 to 0.83). CONCLUSIONS: The addition of vancomycin to cefazolin prophylaxis was not superior to placebo for the prevention of surgical-site infections in arthroplasty among patients without known MRSA colonization. (Funded by the Australian National Health and Medical Research Council; Australian New Zealand Clinical Trials Registry number, ACTRN12618000642280.).

Evidence-based Perioperative Practice Utilization among Various Racial Populations-A Retrospective Cohort Trending Analysis of Lower Extremity Total Joint Arthroplasty Patients.

BACKGROUND: Various studies have demonstrated racial disparities in perioperative care and outcomes. The authors hypothesize that among lower extremity total joint arthroplasty patients, evidence-based perioperative practice utilization increased over time among all racial groups, and that standardized evidence-based perioperative practice care protocols resulted in reduction of racial disparities and improved outcomes. METHODS: The study analyzed 3,356,805 lower extremity total joint arthroplasty patients from the Premier Healthcare database (Premier Healthcare Solutions, Inc., USA). The exposure of interest was race (White, Black, Asian, other). Outcomes were evidence-based perioperative practice adherence (eight individual care components; more than 80% of these implemented was defined as "high evidence-based perioperative practice"), any major complication (including acute renal failure, delirium, myocardial infarction, pulmonary embolism, respiratory failure, stroke, or in-hospital mortality), in-hospital mortality, and prolonged length of stay. RESULTS: Evidence-based perioperative practice adherence rate has increased over time and was associated with reduced complications across all racial groups. However, utilization among Black patients was below that for White patients between 2006 and 2021 (odds ratio, 0.94 [95% CI, 0.93 to 0.95]; 45.50% vs. 47.90% on average). Independent of whether evidence-based perioperative practice components were applied, Black patients exhibited higher odds of major complications (1.61 [95% CI, 1.55 to 1.67] with high evidence-based perioperative practice; 1.43 [95% CI, 1.39 to 1.48] without high evidence-based perioperative practice), mortality (1.70 [95% CI, 1.29 to 2.25] with high evidence-based perioperative practice; 1.29 [95% CI, 1.10 to 1.51] without high evidence-based perioperative practice), and prolonged length of stay (1.45 [95% CI, 1.42 to 1.48] with high evidence-based perioperative practice; 1.38 [95% CI, 1.37 to 1.40] without high evidence-based perioperative practice) compared to White patients. CONCLUSIONS: Evidence-based perioperative practice utilization in lower extremity joint arthroplasty has been increasing during the last decade. However, racial disparities still exist with Black patients consistently having lower odds of evidence-based perioperative practice adherence. Black patients (compared to the White patients) exhibited higher odds of composite major complications, mortality, and prolonged length of stay, independent of evidence-based perioperative practice use, suggesting that evidence-based perioperative practice did not impact racial disparities regarding particularly the Black patients in this surgical cohort.

Are responders to patient health surveys representative of those invited to participate? An analysis of the Patient-Reported Outcome Measures Pilot from the Australian Orthopaedic Association National Joint Replacement Registry.

BACKGROUND: Patient-reported outcome measures (PROMs) are commonly used to evaluate surgical outcome in patients undergoing joint replacement surgery, however routine collection from the target population is often incomplete. Representative samples are required to allow inference from the sample to the population. Although higher capture rates are desired, the extent to which this improves the representativeness of the sample is not known. We aimed to measure the representativeness of data collected using an electronic PROMs capture system with or without telephone call follow up, and any differences in PROMS reporting between electronic and telephone call follow up. METHODS: Data from a pilot PROMs program within a large national joint replacement registry were examined. Telephone call follow up was used for people that failed to respond electronically. Data were collected pre-operatively and at 6 months post-operatively. Responding groups (either electronic only or electronic plus telephone call follow up) were compared to non-responders based on patient characteristics (joint replaced, bilaterality, age, sex, American Society of Anesthesiologist (ASA) score and Body Mass Index (BMI)) using chi squared test or ANOVA, and PROMs for the two responder groups were compared using generalised linear models adjusted for age and sex. The analysis was restricted to those undergoing primary elective hip, knee or shoulder replacement for osteoarthritis. RESULTS: Pre-operatively, 73.2% of patients responded electronically and telephone follow-up of non-responders increased this to 91.4%. Pre-operatively, patients responding electronically, compared to all others, were on average younger, more likely to be female, and healthier (lower ASA score). Similar differences were found when telephone follow up was included in the responding group. There were little (if any) differences in the post-operative comparisons, where electronic responders were on average one year younger and were more likely to have a lower ASA score compared to those not responding electronically, but there was no significant difference in sex or BMI. PROMs were similar between those reporting electronically and those reporting by telephone. CONCLUSION: Patients undergoing total joint replacement who provide direct electronic PROMs data are younger, healthier and more likely to be female than non-responders, but these differences are small, particularly for post-operative data collection. The addition of telephone call follow up to electronic contact does not provide a more representative sample. Electronic-only follow up of patients undergoing joint replacement provides a satisfactory representation of the population invited to participate.

What Is the Implant Survivorship and Functional Outcome After Total Humeral Replacement in Patients with Primary Bone Tumors?

BACKGROUND: Total humeral replacement is an option to reconstruct massive bone defects after resection of locally advanced bone tumors of the humerus. However, implant survivorship, potential risk factors for implant revision surgery, and functional results of total humeral replacement are poorly elucidated because of the rarity of the procedure. QUESTIONS/PURPOSES: We asked: (1) What is the revision-free implant and overall limb survivorship after total humerus replacement? (2) What factors are associated with implant revision surgery? (3) What is the functional outcome of the procedure as determined by the Musculoskeletal Tumor Society (MSTS) score and the American Shoulder and Elbow Surgeons (ASES) score? METHODS: Between August 1999 and December 2018, 666 patients underwent megaprosthetic reconstruction after resection of a primary malignant or locally aggressive/rarely metastasizing tumor of the long bones at our department. In all, 23% (154) of these patients had a primary tumor located in the humerus. During the study, we performed total humeral replacement in all patients with a locally advanced sarcoma, in patients with pathological fractures, in patients with skip metastases, or in patients with previous intralesional contaminating surgery, who would have no sufficient bone stock for a stable implant fixation for a single joint megaprosthetic replacement of the proximal or distal humerus. We performed no biological reconstructions or reconstructions with allograft-prosthetic composites. As a result, 5% (33 of 666) of patients underwent total humerus replacement. Six percent (2 of 33) of patients were excluded because they received a custom-made, three-dimensionally (3-D) printed hemiprosthesis, leaving 5% (31) of the initial 666 patients for inclusion in our retrospective analysis. Of these, 6% (2 of 31) had surgery more than 5 years ago, but they had not been seen in the last 5 years. Median (interquartile range) age at the time of surgery was 15 years (14 to 25 years), and indications for total humeral replacement were primary malignant bone tumors (n = 30) and a recurring, rarely metastasizing bone tumor (n = 1). All megaprosthetic reconstructions were performed with a single modular system. The implanted prostheses were silver-coated beginning in 2006, and beginning in 2010, a reverse proximal humerus component was used when appropriate. We analyzed endoprosthetic complications descriptively and assessed the functional outcome of all surviving patients who did not undergo secondary amputation using the 1993 MSTS score and the ASES score. The median (IQR) follow-up in all survivors was 75 months (50 to 122 months), with a minimum follow-up period of 25 months. We evaluated the following factors for possible association with implant revision surgery: age, BMI, reconstruction length, duration of surgery, extraarticular resection, pathological fracture, previous intralesional surgery, (neo-)adjuvant radio- and chemotherapy, and metastatic disease. RESULTS: The revision-free implant survivorship at 1 year was 77% (95% confidence interval 58% to 89%) and 74% (95% CI 55% to 86%) at 5 years. The overall limb survivorship was 93% (95% CI 75% to 98%) after 1 and after 5 years. We found revision-free survivorship to be lower in patients with extraarticular shoulder resection compared with intraarticular resections (50% [95% CI 21% to 74%] versus 89% [95% CI 64% to 97%]) after 5 years (subhazard ratios for extraarticular resections 4.4 [95% CI 1.2 to 16.5]; p = 0.03). With the number of patients available for our analysis, we could not detect a difference in revision-free survivorship at 5 years between patients who underwent postoperative radiotherapy (40% [95% CI 5% to 75%]) and patients who did not (81% [95% CI 60% to 92%]; p = 0.09). The median (IQR) MSTS score in 9 of 13 surviving patients after a median follow-up of 75 months (51 to 148 months) was 87% (67% to 92%), and the median ASES score was 83 (63 to 89) of 100 points, with higher scores representing better function. CONCLUSION: Total humeral replacement after resection of locally advanced bone tumors appears to be associated with a good functional outcome in patients who do not die of their tumors, which in our study was approximately one- third of those who were treated with a resection and total humerus prosthesis. However, the probability of early prosthetic revision surgery is high, especially in patients undergoing extraarticular resections, who should be counseled accordingly. Still, our results suggest that if the prosthesis survives the first year, further risk for revision appears to be low. Future studies should reexamine the effect of postoperative radiotherapy on implant survival in a larger cohort and evaluate whether the use of soft tissue coverage with plastic reconstructive surgery might decrease the risk of early revisions, especially in patients undergoing extraarticular resections. LEVEL OF EVIDENCE: Level III, therapeutic study.

Increased Utilization of Total Joint Arthroplasty After Medicaid Expansion.

BACKGROUND: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

Non-surgical treatment before hip and knee arthroplasty remains underutilized with low satisfaction regarding performance of work, sports, and leisure activities.

Background and purpose - Guidelines for managing hip and knee osteoarthritis (OA) advise extensive non-surgical treatment prior to surgery. We evaluated what percentage of hip and knee OA patients received non-surgical treatment prior to arthroplasty, and assessed patient satisfaction regarding alleviation of symptoms and performance of activities. Patients and methods - A multi-center cross-sectional study was performed in 2018 among 186 patients who were listed for hip or knee arthroplasty or had undergone surgery within the previous 6 months in the Netherlands. Questions concerned non-surgical treatments received according to the Stepped Care Strategy and were compared with utilization in 2013. Additionally, satisfaction with treatment effects for pain, swelling, stiffness, and activities of daily life, work, and sports/leisure was questioned. Results - The questionnaire was completed by 175 patients, age 66 years (range 38-84), 57% female, BMI 29 (IQR 25-33). Step 1 treatments, such as acetaminophen and lifestyle advice, were received by 79% and 60% of patients. Step 2 treatments, like exercise-based therapy and diet therapy, were received by 66% and 19%. Step 3-intra-articular injection-was received by 47%. Non-surgical treatment utilization was lower than in 2013. Nearly all treatments showed more satisfied patients regarding pain relief and fewer regarding activities of work/sports/leisure. Hip and knee OA patients were mostly satisfied with NSAIDs for all outcomes, while exercise-based therapy was rated second best. Interpretation - Despite international guideline recommendations, non-surgical treatment for hip and knee OA remains underutilized in the Netherlands. Of the patients referred for arthroplasty, more were satisfied with the effect of non-surgical treatment on pain than on work/sports/leisure participation.

Increases in the rates of primary and revision knee replacement are reducing: a 15-year registry study across 3 continents.

Background and purpose - Rates of knee replacement (KR) are increasing worldwide. Based on population and practice changes, there are forecasts of a further exponential increase in primary knee replacement through to 2030, and a corresponding increase in revision knee replacement. We used registry data to document changes in KR over the past 15 years, comparing practice changes across Sweden, Australia, and the United States. This may improve accuracy of future predictions.Patients and methods - Aggregated data from the Swedish Knee Arthroplasty Register (SKAR), the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), and the Kaiser Permanente Joint Replacement Registry (KPJRR) were used to compare surgical volume of primary and revision KR from 2003 to 2017. Incidence was calculated using population census statistics from Statistics Sweden and the Australian Bureau of Statistics, as well as the yearly active membership numbers from Kaiser Permanente. Further analysis of KR by age < 65 and ≥ 65 years was carried out.Results - All registries recorded an increase in primary and revision KR, with a greater increase seen in the KPJRR. The rate of increase slowed during the study period. In Sweden and Australia, there was a smaller increase in revision surgery compared with primary procedures. There was consistency in the mean age at surgery, with a steady small decrease in the proportion of women having primary KR. The incidence of KR in the younger age group remained low in all 3 registries, but the proportional increases were greater than those seen in the ≥ 65 years of age group.Interpretation - There has been a generalized deceleration in the rate of increase of primary and revision KR. While there are regional differences in KR incidence, and rates of change, the rate of increase does not seem to be as great as previously predicted.

Partnership Across Transitions to Improve Outcomes in the Lower Extremity Total Joint Population.

BACKGROUND: With the urgency related to improving quality and creating efficiency in healthcare, partnership is emerging as a critical concept related to transitions of care. PURPOSE: This quality improvement project included facilitation of hospital partnership with skilled nursing facilities to improve outcomes associated with the lower extremity total joint arthroplasty population. METHODS: The clinical nurse specialist (CNS) utilized a standardized framework to implement partnership strategies with multidisciplinary teams. Outcomes were monitored for the 2 quarters of partnership activities. RESULTS: All recommendations for developing a partnership model were facilitated within the project timeline. Patient experience and quality measures remained at, or improved, from baseline and met all strategic targets. Efficiency through episode payment demonstrated improvement at each interval during the study period. Analysis revealed a significant (p < .05) reduction in the mean hospital length of stay. CONCLUSION: The CNS practice outcomes suggest that the use of structured partnership strategies between agencies improves efficiency of care and accelerates rapid spread of innovation.

Challenges to Implementing Total Joint Replacement Programs in Developing Countries.

In this review article, the authors present the many challenges that orthopedic surgeons in developing countries face when implementing arthroplasty programs. The issues of cost, sterility, and patient demographics are specifically addressed. Despite the many challenges, developing countries are beginning to offer hip and knee reconstructive surgery to respond to the increasing demand for such elective operations as the prevalence of osteoarthritis continues to increase. The authors shed light on these nascent arthroplasty programs.

Long-term effect of patient decision aids on use of joint replacement and health care costs.

OBJECTIVE: Shared decision-making supported by patient decisions aids may improve care and reduce healthcare costs for persons considering total joint replacement. Observational studies and randomized controlled trials (RCTs) have evaluated the short-term impact of decision aids on uptake of surgery and costs, however the long-term effects are unclear. This analysis aimed to evaluate the effect of patient decision aids on 1) use of joint replacement up to 7-years of follow-up, and 2) osteoarthritis-related health system costs. METHODS: 324 participants in a Canadian RCT with 2-years follow-up who were randomized to either a decision aid (n = 161) or usual care (n = 163) had their trial and health administrative data linked. The proportion undergoing surgery up to 7-years were compared using cumulative incidence plots and competing risk regression. Mean per-patient costs were compared using two sample t-tests. RESULTS: At 2-years, 119 of 161 (73.9%) patients in the decision aid arm and 129 of 163 (79.1%) patients in the usual care arm had surgery. Between two and 7-years, 17 additional patients in both the decision aid (of 42, 40.4%) and usual care (of 34, 50.0%) arms underwent surgery. At 7-years, patients exposed to decision aids had a similar likelihood of undergoing surgery (HR = 0.92, 95% CI:0.73 to 1.17, p = 0.49) and mean per-patient costs ($21,965 vs $23,681, incremental cost: -$1,717, 95% CI:-$5,631 to $2,198) compared to those in usual care. CONCLUSIONS: This is the first study to assess the long-term impact of decision aids on use of joint replacement and healthcare costs. These results are not conclusive but can inform future trial design. CLINICAL TRIAL REGISTRATION: The full trial protocol is available at ClinicalTrials.Gov (NCT00911638).

Factors associated with emergency department presentation after total joint arthroplasty: a population-based retrospective cohort study.

BACKGROUND: Unplanned visits to the emergency department after total joint arthroplasty are far more common than unplanned readmissions. Our objectives were to characterize the prevalence of presentation to an emergency department for any reason after total joint arthroplasty and to identify risk factors for such visits. METHODS: Using health administrative databases, we conducted a population-based retrospective cohort study of adults (19-89 yr of age) who received their first primary elective total hip arthroplasty (THA) or total knee arthroplasty (TKA) procedure for arthritis between April 2011 and March 2016 in Ontario. We made univariate comparisons between patients who presented to the emergency department within 30 days of surgery and those who did not in. We determined differences in use of health care services between groups by comparing the change in use in the year before and after surgery between patients who presented to the emergency department and those who did not. We developed logistic regression models for the occurrence of an emergency department visit using backward variable elimination. RESULTS: We identified 42 273 total hip recipients and 70 725 total knee recipients, of whom 5640 (13.3%) and 11 224 (15.9%), respectively, presented to the emergency department within 30 days of surgery. Fewer than 1% of these patients required admission, and nearly half (45%) went to a different institution from where they had their surgery. Among both THA and TKA recipients, patients who presented to the emergency department had a net increase in their median annual health care costs (THA: $501, TKA: $682), compared to a net decrease for the cohort as a whole. Factors associated with increased risk of an emergency visit included increased patient age, male sex, rural residence and various comorbidities. Predictive regression models showed poor discriminative ability for both THA (C-statistic 0.57) and TKA (C-statistic 0.58) recipients. INTERPRETATION: One in 7 patients presented to the emergency department within 30 days of THA or TKA. Some may conceivably have been managed remotely, and very few required readmission. There is a crucial need for strategies to minimize these events.

Payments for outpatient joint replacement surgery: A comparison of hospital outpatient departments and ambulatory surgery centers.

OBJECTIVE: To compare commercial insurance payments for outpatient total knee and hip replacement surgeries performed in hospital outpatient departments (HOPDs) and in ambulatory surgery centers (ASCs). DATA SOURCES: A large national claims database that contains information on actual prices paid to providers over the period 2014-2017. DATA COLLECTION: We identified all patients receiving total knee replacement surgery and total hip replacement surgery in HOPDs and in ASCs for each of the 4 years. STUDY DESIGN: For each year, we conducted descriptive and statistical patient-level analyses of the facility component of payments to HOPDs and to ASCs. PRINCIPAL FINDINGS: For each procedure and for each year, ASC payments exceeded HOPD payments by a wide margin; however, the gap across settings declined over time. In 2014, knee replacement payments to HOPDs (n = 67) were $6016 compared to $23 244 in ASCs (n = 68). By 2017, payments to HOPDs (n = 223) had grown to $10 060 compared to $18 234 in ASCs (n = 602). Similarly, for hip replacements, HOPD payments (n = 43) rose from $6980 in 2014 to $11 139 in 2017 (n = 206) and in ASCs fell from $28 485 in 2014 (n = 82) to $18 595 in 2017 (n = 465). CONCLUSIONS: Results suggest that for total joint replacement, common perceptions of cost savings from transition of services from hospitals to ASCs may be misguided.

The cartilage degradation marker, urinary CTX-II, is associated with the risk of incident total joint replacement in postmenopausal women. A 18 year evaluation of the OFELY prospective cohort.

OBJECTIVE: Identifying objective risk-indicators for total joint replacement (TJR) is useful to enrich population at high risk in OA clinical trials. We investigate the association of urinary CTX-II, a biochemical marker of cartilage breakdown, with the risk of TJR. METHOD: 478 postmenopausal women (mean age 65.5 ± 7.5 yr) from the OFELY cohort were studied. CTX-II, serum CTX-I (bone resorption) and PINP (bone formation), were measured at baseline. Association between CTX-II and incidence of TJR was assessed by Cox Hazard Regression. RESULTS: During a median (95%CI) 17.8 (15.0-18.1) years follow-up, 38 women sustained a TJR, including hip (n = 29) or knee (n = 9) replacement. CTX-II -but not CTX-I or PINP- was higher in patients with TJR (+34%, P = 0.001 vs women with no TJR). Increased baseline CTX-II levels were associated with a higher risk of TJR with a Hazard Ratio (HR) (95 CI) of 1.45 (1.13-1.85) per 1 SD increase after adjustment for age, BMI and total hip BMD. CTX-II remained significantly associated with the risk of TJR after further adjustment for total WOMAC, prevalent knee OA (KL ≥ 2) and self-reported hip OA [HR (95 CI): 1.31 (1.01-1.71), P = 0,04]. When women were categorized as low and high CTX-II (lower and above the 95 percentile of healthy premenopausal women, respectively), subjects with high levels had an age-BMI-hip BMD adjusted HR (95 CI) of 3.00 (1.54-5.85) compared to women with low levels which remained significant after further adjustment for WOMAC, knee and/or hip OA [HR (95 CI): 2.45 (1.25-4.89), P = 0.01]. CONCLUSION: CTX-II is an independent risk indicator of TJR in postmenopausal women suggesting that it may be useful to identify subjects at high risk of TJR.