Search

Background: Highly cross-linked polyethylene (HXLPE) can improve wear properties in TKA, but it can also lead to decreased mechanical properties. Antioxidants were added to HXLPE to improve its mechanical properties while retaining the improved wear characteristics. However, it remains unclear whether these modifications to conventional polytheylene used in TKA have resulted in a change in the revision risk.Questions/purposes: We used American Joint Replacement Registry data to ask: (1) Is there a difference in all-cause revision in patients who underwent TKA using HXLPE with or without an antioxidant doping compared with conventional polyethylene? (2) Is there a difference in revision for aseptic failure in patients who underwent TKA using HXLPE with or without an antioxidant doping compared with conventional polyethylene?Methods: We analyzed American Joint Replacement Registry data from 2012 to 2019. We identified 339,366 primary TKAs over the study period in patients older than 65 years and linked procedures to supplemental Centers for Medicare & Medicaid data where available. Patient total number of reported comorbidities, gender, age, region, polyethylene characteristics, procedure dates, and indication for revision were recorded. Median follow-up was 34 months. We compared HXLPE with or without antioxidants to conventional polyethylene. Event-free percent survival curves and Cox proportional hazard regression modeling was used for all-cause revision and revision for aseptic failure.Results: Compared with conventional polyethylene, there was no difference in all-cause revision with HXLPE with an antioxidant (HR 1.06 [95% CI 0.98 to 1.14]; p = 0.13) or HXLPE without an antioxidant (HR 1.04 [95% CI 0.97 to 1.11]; p = 0.28). Compared with conventional polyethylene, there was no difference in revision for aseptic failure with HXLPE with an antioxidant (HR 1.07 [95% CI 0.99 to 1.14]; p = 0.08) or HXLPE without an antioxidant (HR 1.03 [95% CI 0.97 to 1.01]; p = 0.30).Conclusion: We found no difference in revision risk between HXLPE with or without an antioxidant and conventional polyethylene during this time frame. HXLPE polyethylene, with or without an antioxidant, should not be widely adopted until or unless it is shown to be superior to conventional polyethylene in TKA.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Polyethylene bearing design may influence the risk of revision after total knee arthroplasty (TKA). Previous investigations from outside of the United States have suggested the potential for an increased risk of all-cause revision and revision for infection with the use of posterior-stabilized bearings. We examine the risk of revision based on the polyethylene bearing design selection for primary TKA.Methods: An analysis of the American Joint Replacement Registry (AJRR) data from 2012 to 2019 was performed. We identified all primary TKAs over the study period and linked cases to supplemental U.S. Centers for Medicare & Medicaid Services (CMS) data where available. Patient demographic characteristics, polyethylene characteristics, procedure dates, and cause for revision were recorded. Analysis was performed to compare minimally stabilized implants (cruciate-retaining, anterior-stabilized, or pivot bearing designs) with posterior-stabilized implants. Cumulative incidence function (CIF) curves and Cox proportional hazard ratios (HRs) were created for all-cause revision and revision for infection in each group.Results: We identified 305,279 cases with reported minimally stabilized or posterior-stabilized implant characteristics. There were 161,486 cases (52.9%) that utilized posterior-stabilized bearings compared with 143,793 cases (47.1%) with minimally stabilized bearings. For minimally stabilized bearings, 1,693 cases (1.18%) had all-cause revision and 334 cases (0.23%) had revision for infection. For posterior-stabilized bearings, 2,406 cases (1.49%) had all-cause revision and 446 cases (0.28%) had revision for infection. The use of posterior-stabilized bearings had HRs of 1.25 (95% confidence interval [CI], 1.2 to 1.3; p < 0.0001) for all-cause revision and 1.18 (95% CI, 1.0 to 1.4; p = 0.02) for revision for infection.Conclusions: Similar to investigations from international registries, we found an increased risk of all-cause revision and revision for infection when using posterior-stabilized bearings in TKA in the United States. Surgeons should consider this finding when considering bearing selection for primary TKA.Level Of Evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Importance: Transformation of US health care from volume to value requires meaningful quantification of costs and outcomes at the level of individual patients.Objective: To measure the association of a value-driven outcomes tool that allocates costs of care and quality measures to individual patient encounters with cost reduction and health outcome optimization.Design, Setting, and Participants: Uncontrolled, pre-post, longitudinal, observational study measuring quality and outcomes relative to cost from 2012 to 2016 at University of Utah Health Care. Clinical improvement projects included total hip and knee joint replacement, hospitalist laboratory utilization, and management of sepsis.Exposures: Physicians were given access to a tool with information about outcomes, costs (not charges), and variation and partnered with process improvement experts.Main Outcomes and Measures: Total and component inpatient and outpatient direct costs across departments; cost variability for Medicare severity diagnosis related groups measured as coefficient of variation (CV); and care costs and composite quality indexes.Results: From July 1, 2014, to June 30, 2015, there were 1.7 million total patient visits, including 34 000 inpatient discharges. Professional costs accounted for 24.3% of total costs for inpatient episodes ($114.4 million of $470.4 million) and 41.9% of total costs for outpatient visits ($231.7 million of $553.1 million). For Medicare severity diagnosis related groups with the highest total direct costs, cost variability was highest for postoperative infection (CV = 1.71) and sepsis (CV = 1.37) and among the lowest for organ transplantation (CV ≤ 0.43). For total joint replacement, a composite quality index was 54% at baseline (n = 233 encounters) and 80% 1 year into the implementation (n = 188 encounters) (absolute change, 26%; 95% CI, 18%-35%; P < .001). Compared with the baseline year, mean direct costs were 7% lower in the implementation year (95% CI, 3%-11%; P < .001) and 11% lower in the postimplementation year (95% CI, 7%-14%; P < .001). The hospitalist laboratory testing mean cost per day was $138 (median [IQR], $113 [$79-160]; n = 2034 encounters) at baseline and $123 (median [IQR], $99 [$66-147]; n = 4276 encounters) in the evaluation period (mean difference, -$15; 95% CI, -$19 to -$11; P < .001), with no significant change in mean length of stay. For a pilot sepsis intervention, the mean time to anti-infective administration following fulfillment of systemic inflammatory response syndrome criteria in patients with infection was 7.8 hours (median [IQR], 3.4 [0.8-7.8] hours; n = 29 encounters) at baseline and 3.6 hours (median [IQR], 2.2 [1.0-4.5] hours; n = 76 encounters) in the evaluation period (mean difference, -4.1 hours; 95% CI, -9.9 to -1.0 hours; P = .02).Conclusions and Relevance: Implementation of a multifaceted value-driven outcomes tool to identify high variability in costs and outcomes in a large single health care system was associated with reduced costs and improved quality for 3 selected clinical projects. There may be benefit for individual physicians to understand actual care costs (not charges) and outcomes achieved for individual patients with defined clinical conditions. [ABSTRACT FROM AUTHOR]

Background: Aseptic loosening persists as one of the leading causes of failure following cemented primary total knee arthroplasty (TKA). Cement technique may impact implant fixation. We hypothesized that there is variability in TKA cement technique among arthroplasty surgeons., Methods: A 28-question survey regarding variables in surgeons' preferred TKA cementation technique was distributed to 2,791 current American Association of Hip and Knee Surgeons (AAHKS) members with a response rate of 30.8% (903 respondents). Patterns of responses were analyzed by grouping respondents by their answers to certain questions including cementing technique, tibial cement location, and femoral cement location., Results: A total of 73.5% reported performing at least 7 of 8 of the highest consensus techniques, including vacuum mixing (79.9%), using two bags (76.1%), tibial implant first (95.2%), single-stage cementing (96.9%), compression of the implants in extension (91.7%), and use of a tourniquet (84.3%). Medium and high viscosity cement was most commonly used (37.9 and 37.8%, respectively). Finger pressurization was most common (76.1%) compared to a gun (29.8%). There were 26.5% of respondents performing 6 or fewer of the most common majority techniques and seemed to perform other less common techniques (eg, use of a single bag of cement, trialing or closure prior to cement curing, and heating to accelerate cement curing). Cement was most commonly applied to the entire bone and implant surface on both the tibia (46.4%) and femur (47.7%), leaving much variation in the remaining cement application location responses., Discussion: There appears to be variability in cemented TKA technique among arthroplasty surgeons. There were 26.5% of respondents performing less of the majority techniques and also performed other additional low-response rate techniques. Further studies that look at the impacts of variation in techniques on outcomes may be warranted. Our study demonstrates the need for defining best practices for cement technique given the substantial variability identified., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Mobile-bearing (MB) total knee arthroplasty (TKA) may reduce wear and improve patellar tracking but may increase revision risk due to tibial component design, balance complexity, and bearing dislocation. We utilized the American Joint Replacement Registry to examine risk of revision with MB compared to fixed-bearing (FB) designs., Methods: An analysis of primary TKA in patients over 65 years was performed with American Joint Replacement Registry data linked to Centers for Medicare and Medicaid Services data from 2012 to 2019. Analyses compared MB to FB designs with a subanalysis of implants from a single company. We identified 485,024 TKAs, with 452,199 (93.2%) FB-TKAs and 32,825 (6.8%) MB-TKAs. Cox proportional hazards regression modeling was used for all-cause revision and revision for infection, adjusting for sex, age, and competing risk of mortality. Event-free survival curves evaluated time to all-cause revision and revision for infection., Results: MB-TKAs were at an increased risk for all-cause revision: hazard ratio (HR) 1.36 ([95% confidence interval (CI) 1.24-1.49], P < .0001) but not revision for infection: HR 1.06 ([95% CI 0.90-1.25], P = .52). When comparing implants within a single company, MB-TKAs were at an increased risk of all-cause revision: HR 1.55 ([95% CI 1.38-1.73], P < .0001). Event-free survival curves demonstrated increased risk for all-cause revision for MB-TKA across all time points, with a greater magnitude of risk up to 8 years., Conclusion: Although survivorship of both designs was outstanding, MB-TKA designs demonstrated increased risk for all-cause revision. Additional investigation is needed to determine if this is related to patient selection factors, surgical technique, bearing, or implant design., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: The Center for Medicare and Medicaid Innovation revised the comprehensive Care for Joint Replacement (CJR) program, a mandatory 90-day bundled payment for lower extremity joint replacement, in December 2017, retaining 34 of the original 67 metropolitan statistical areas with higher volume and historic episode payments., Objectives: We describe differences in costs, quality, and patient selection between hospitals that continued to participate compared with those that withdrew from CJR before and after the implementation of CJR., Research Design: We used a triple difference approach to compare the magnitude of the policy effect for elective admissions between hospitals that were retained in the CJR revision or not, before and after the implementation of CJR, and compared with hospitals in nonparticipant metropolitan statistical areas., Subjects: 694,275 Medicare beneficiaries undergoing elective lower extremity joint replacement from January 1, 2013 to August 31, 2017., Measures: The treatment effect heterogeneity of CJR., Results: Hospitals retained in the CJR policy revision had a greater reduction in 90-day episode-of-care cost compared with those that were allowed to discontinue (-$846, 95% CI: -$1,338, -$435) and had greater cost reductions in the more recent year (2017). We also found evidence that retained CJR hospitals disproportionately reduced treating patients who were older than 85 years., Conclusions: Hospitals that continued to participate in CJR after the policy revision achieved a greater cost reduction. However, the cost reductions were partly attributed to avoiding potential higher - cost patients, suggesting that a bundled payment policy might induce disparities in care delivery., Competing Interests: The authors declare no conflict of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Advances in polyethylene bearing characteristics have led to various options for total knee arthroplasty. We examine trends in use of polyethylene in the United States., Methods: An analysis of American Joint Replacement Registry data from 2012 to 2019 for primary total knee arthroplasty procedures was conducted. Design and manufacturing characteristics were obtained and validated in the American Joint Replacement Registry dataset. Polyethylene bearing design and manufacturing use characteristics were compared by year, gender, age group, and geographic region of the procedure. Descriptive analysis was performed., Results: We identified 993,292 cases over the study period. In total, 791,233 (80%) cases had complete device data available and were included in analysis. In addition, 366,280 (49.4%) cases utilized minimally stabilized bearings compared to 374,809 (50.6%) for posterior-stabilized bearings. Posterior-stabilized use was stable over the study period and highest in the Northeast (64.5%; P < .0001). Cruciate-retaining use decreased from 29.7% to 20.2% and anterior-stabilized use increased from 17.4% to 25.2%. Conventional polyethylene use decreased from 42.8% to 21.9%, and was highest in the 81+ age group (37.8%; P < .0001) and Northeast (43.0%; P < .0001). Highly cross-linked polyethylene (HXLPE) with antioxidant use increased from 9.08% to 31.8%, while HXLPE without antioxidant use remained constant., Conclusion: There was an increase in use of anterior-stabilized and pivot bearings and an increase in use of HXLPE with antioxidant. Additionally, there were noted age group and regional differences in the use of various bearings. Further study should evaluate if these changing utilization trends are related to clinical outcomes, or due to regional training, preferences, or manufacturer pressures., Level of Evidence: Level III, retrospective., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objective: To understand whether the Comprehensive Care for Joint Replacement (CJR) program induces participating hospitals to (1) preferentially select lower risk patients, (2) reduce 90-day episode-of-care costs, (3) improve quality of care, and (4) achieve greater cost reduction during its second year, when downside financial risk was applied., Data Sources: We identified beneficiaries of age 65 years or older undergoing hip or knee joint replacement in the 100% sample of Medicare fee-for-service inpatient (Part A) claims from January 1, 2013 to August 31, 2017. Cases were linked to subsequent outpatient, Part B, home health agency, and skilled nursing facility claims, as well as publicly available participation status for CJR., Study Design: We estimated the effect of CJR for hospitals in the 67 metropolitan statistical areas (MSA) selected to participate in CJR (785 hospitals), compared to those in 104 non-CJR MSAs (962 hospitals; maintaining fee-for-service). A difference-in-differences approach was used to detect patient selection, as well as to compare 90-day episode-of-care costs and quality of care between CJR and non-CJR hospitals over the first two performance years., Data Collection: We excluded 172 hospitals from our analysis due to their preexisting BPCI participation. We focused on elective admissions in the main analysis., Principal Findings: While reductions in 90-day episode-of-care costs were greater among CJR hospitals (-$902, 95% CI: -$1305, -$499), largely driven by a 16.8% (p < 0.01) decline in 90-day spending in skilled nursing facilities, CJR hospitals significantly reduced the 90-day readmission rate (-3.9%; p < 0.05) and preferentially avoided patients aged 85 years or older (-5.9%; p < 0.01) and Black (-7.0%; p < 0.01). Cost reduction was greater in 2017 than in 2016, corresponding to the start of downside risk., Conclusions: Participation in CJR was associated with a modest cost reduction and a reduction in 90-day readmission rates; however, we also observed evidence of preferential avoidance of older patients perceived as being higher risk among CJR hospitals., (© 2021 Health Research and Educational Trust.)

Background: Patient-reported outcomes are essential to demonstrate the value of hip and knee arthroplasty, a common target for payment reforms. We compare patient-reported global and condition-specific outcomes after hip and knee arthroplasty based on hospital participation in Medicare's bundled payment programs., Methods: We performed a prospective observational study using the Comparative Effectiveness of Pulmonary Embolism Prevention after Hip and Knee Replacement trial. Differences in patient-reported outcomes through 6 months were compared between bundle and nonbundle hospitals using mixed-effects regression, controlling for baseline patient characteristics. Outcomes were the brief Knee Injury and Osteoarthritis Outcomes Score or the brief Hip Disability and Osteoarthritis Outcomes Score, the Patient-Reported Outcomes Measurement Information System Physical Health Score, and the Numeric Pain Rating Scale, measures of joint function, overall health, and pain, respectively., Results: Relative to nonbundled hospitals, arthroplasty patients at bundled hospitals had slightly lower improvement in Knee Injury and Osteoarthritis Outcomes Score (-1.8 point relative difference at 6 months; 95% confidence interval -3.2 to -0.4; P = .011) and Hip Disability and Osteoarthritis Outcomes Score (-2.3 point relative difference at 6 months; 95% confidence interval -4.0 to -0.5; P = .010). However, these effects were small, and the proportions of patients who achieved a minimum clinically important difference were similar. Preoperative to postoperative change in the Patient-Reported Outcomes Measurement Information System Physical Health Score and Numeric Pain Rating Scale demonstrated a similar pattern of slightly worse outcomes at bundled hospitals with similar rates of achieving a minimum clinically important difference., Conclusions: Patients receiving care at hospitals participating in Medicare's bundled payment programs do not have meaningfully worse improvements in patient-reported measures of function, health, or pain after hip or knee arthroplasty., (Copyright © 2019 Elsevier Inc. All rights reserved.)