Ninety-Day Readmissions and Resource Utilization After Hip Resurfacing Versus Total Hip Arthroplasty in Patients Aged 45-65 Years: A Propensity Score-Matched Analysis of the Nationwide Readmissions Database

Ninety-Day Readmissions and Resource Utilization After Hip Resurfacing Versus Total Hip Arthroplasty in Patients Aged 45-65 Years: A Propensity Score-Matched Analysis of the Nationwide Readmissions Database | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Ninety-Day Readmissions and Resource Utilization After Hip Resurfacing Versus Total Hip Arthroplasty in Patients Aged 45-65 Years: A Propensity Score-Matched Analysis of the Nationwide Readmissions Database David Maman, Yaniv Steinfeld, Yaron Berkovic This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9233634/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 5 You are reading this latest preprint version Abstract Background Hip resurfacing arthroplasty (HRA) is selectively used for younger, active patients with hip osteoarthritis as a bone-preserving alternative to conventional total hip arthroplasty (THA). Contemporary national data comparing short-term, episode-of-care outcomes-including 90-day readmission and readmission resource utilization-remain limited in typical resurfacing-eligible patients. Methods We performed a retrospective cohort study using the Nationwide Readmissions Database (NRD), 2020–2022. Elective, osteoarthritis-related primary hip arthroplasty admissions with the procedure performed on hospital day 0 were identified. The analytic cohort was restricted to males aged 45–65 years. Patients undergoing HRA were compared with those undergoing THA using 1:5 nearest-neighbor propensity score matching without replacement, incorporating demographics, payer, calendar year, residence category, hospital characteristics, and comorbidities (obesity, hypertension, dyslipidemia, obstructive sleep apnea, chronic anemia, osteoporosis, type 2 diabetes mellitus, chronic kidney disease, congestive heart failure, and chronic lung disease). The primary endpoint was all-cause 90-day readmission. Secondary outcomes included index hospitalization length of stay and charges, selected in-hospital complications, and readmission-level utilization among readmitted patients. Results The matched cohort included 3,398 admissions (THA n = 2,844; HRA n = 553). Baseline balance was achieved after matching. Index hospitalization charges were higher for HRA ( $ 84,555 ± 49,002) than THA ( $ 66,260 ± 39,393; p < 0.001), while index length of stay was slightly longer after THA (1.37 ± 1.46 vs 1.21 ± 1.12 days; p = 0.018). In-hospital mortality was not observed. Blood loss anemia occurred more frequently after THA (8.9% vs 5.1%; p = 0.003). Ninety-day readmission occurred in 2.7% after THA and 3.1% after HRA, with no statistically significant difference (p = 0.596). Among readmitted patients, readmission length of stay (5.65 ± 5.23 vs 3.01 ± 3.22 days; p = 0.010) and charges ( $ 77,852 ± 68,606 vs $ 44,114 ± 25,112; p = 0.001) were higher after THA, while time to readmission and the proportion with any inpatient procedure during readmission were similar. Conclusions In males aged 45–65 years undergoing elective, same-day primary hip arthroplasty, HRA was associated with higher index hospitalization charges but similar 90-day readmission rates compared with THA. Among patients who were readmitted, THA was associated with greater readmission resource utilization. These findings provide contemporary national episode-of-care benchmarks and support nuanced, value-informed counseling in appropriately selected candidates. Levels of Evidence: Level III hip resurfacing total hip arthroplasty Nationwide Readmissions Database propensity score matching 90-day readmission resource utilization charges length of stay Introduction Total hip arthroplasty (THA) is among the most successful elective procedures for end-stage hip osteoarthritis, reliably improving pain and function. [1] However, patients in midlife who remain highly active represent a distinct subgroup in which long-term implant durability, return to demanding activity, and preservation of proximal femoral bone stock are particularly important. [2,3] Hip resurfacing arthroplasty (HRA) was reintroduced to address some of these priorities by conserving femoral bone, restoring native hip biomechanics, and using a large-diameter femoral head that may reduce instability risk through increased jump distance. [4,5] In carefully selected patients-most commonly males with primary osteoarthritis and adequate bone quality-contemporary resurfacing systems have demonstrated encouraging survivorship in experienced centers. [6] At the same time, resurfacing introduces procedure-specific considerations, particularly those related to metal-on-metal bearings, including adverse local tissue reactions and elevated metal ion levels that may necessitate surveillance and, in some cases, revision. [7,8] While prior comparative work has focused heavily on longer-term survivorship and revision risk, less is known about contemporary short-term episode-of-care outcomes at a national level among typical resurfacing-eligible patients. [3,6] This is clinically relevant because early readmissions and readmission-associated resource use are widely used quality and value metrics and reflect meaningful early postoperative events. [9,10] Using a contemporary all-payer national readmissions dataset, we compared elective primary THA versus HRA in a restricted “resurfacing-eligible” male cohort aged 45–65 years, emphasizing 90-day readmission, readmission-associated procedures, and readmission resource utilization after 1:5 propensity score matching. Materials and Methods This retrospective cohort study used the Nationwide Readmissions Database (NRD) from 2020 through 2022, a Healthcare Cost and Utilization Project (HCUP) dataset that permits linkage of readmissions occurring within the same calendar year. Because the NRD contains de-identified data, this study was deemed exempt from review by the Carmel Medical Center Institutional Review Board. The study was conducted in accordance with the ethical standards of the institutional and national research committee and with the 1964 Declaration of Helsinki and its later amendments. Informed consent was not required because the NRD is a de-identified administrative database. Adult patients undergoing elective primary hip arthroplasty were identified using ICD-10-PCS procedure coding during the index hospitalization. To reduce heterogeneity in perioperative trajectories and improve comparability between procedure types, the analytic sample was restricted to elective admissions in which the procedure occurred on hospital day 0. Revision procedures, urgent or trauma-related admissions, and discharges carrying COVID-19 diagnosis codes were excluded to reduce confounding by pandemic-related case-mix and care pathways. Records missing essential variables required for propensity score modeling or outcome evaluation were excluded using a complete-case approach. Because HRA is predominantly performed in males and female HRA cases were sparse and not clinically comparable within administrative data, the analytic cohort was restricted to males. To further align groups and reduce selection differences by age, the cohort was restricted to patients aged 45–65 years at admission. The exposure was index procedure type, categorized as conventional total hip arthroplasty versus hip resurfacing arthroplasty based on ICD-10-PCS procedure coding during the index admission. Covariates used for propensity score modeling were selected a priori based on clinical relevance to arthroplasty outcomes and readmission risk. These included age, primary payer, calendar year, residence category (National Center for Health Statistics urban-rural classification), hospital characteristics (region, bed size, and teaching status), and the following comorbidities captured from ICD-10-CM diagnosis coding: obesity, hypertension, dyslipidemia, obstructive sleep apnea, chronic anemia, osteoporosis, type 2 diabetes mellitus, chronic kidney disease, congestive heart failure, and chronic lung disease. The primary outcome was all-cause 90-day readmission. Secondary outcomes included index hospitalization resource utilization (length of stay and total hospital charges) and selected in-hospital postoperative events during the index admission (blood loss anemia, intraoperative fracture, dislocation, and acute renal failure). Among patients who were readmitted, readmission resource utilization outcomes included days from discharge to readmission, readmission length of stay, readmission total charges, and whether any inpatient procedure occurred during readmission. The discharge-to-readmission interval was derived by anchoring the NRD timing variable to discharge rather than admission, consistent with standard NRD episode-of-care practice and the analytic approach used in this project. Propensity scores estimating the likelihood of undergoing HRA were computed using logistic regression including all covariates listed above. Patients were matched 1:5 (HRA:THA) using nearest-neighbor matching without replacement. Covariate balance was assessed using standardized mean differences, with values < 0.10 considered indicative of adequate balance. Continuous variables are reported as mean ± standard deviation and compared using independent-samples t-tests; when Levene’s test suggested unequal variances, Welch’s correction was applied. Categorical variables are reported as percentages and compared using chi-square testing or Fisher’s exact testing when appropriate. All tests were two-sided with statistical significance set at p < 0.05. Analyses were performed in SPSS (IBM). Results Matched cohort characteristics and index hospitalization utilization The final propensity score-matched cohort included 3,398 elective primary hip arthroplasty admissions among males aged 45–65 years, comprising 2,844 conventional total hip arthroplasties and 553 hip resurfacings, consistent with the planned 5:1 matching ratio. Post-matching balance was achieved across measured baseline characteristics and comorbidities, with no clinically meaningful residual differences between groups (Table 1 ). Mean age was similar between groups (55.12 ± 5.27 years for THA vs 54.83 ± 5.29 years for HRA; p = 0.241). Index hospitalization charges were higher for HRA ( $ 84,555 ± 49,002) compared with THA ( $ 66,260 ± 39,393; p < 0.001). Index length of stay was slightly longer for THA (1.37 ± 1.46 days) than for HRA (1.21 ± 1.12 days; p = 0.018). Calendar year distribution did not differ between groups (p = 0.877). Prevalence of matched comorbidities was closely aligned after matching (Table 1 ). Table 1 Matched cohort characteristics and index hospitalization resource use (age 45–65 years) Characteristic Total hip arthroplasty (n = 2,844) Hip resurfacing (n = 553) p-value Age, years (mean ± SD) 55.12 ± 5.27 54.83 ± 5.29 0.241 Index total charges, USD (mean ± SD) 66,260 ± 39,393 84,555 ± 49,002 < 0.001 Index length of stay, days (mean ± SD) 1.37 ± 1.46 1.21 ± 1.12 0.018 Calendar year (mean ± SD) 2020.50 ± 0.72 2020.50 ± 0.71 0.877 Obesity 34.0% 34.0% 1.000 Hypertension 33.1% 32.7% 0.836 Dyslipidemia 28.4% 28.5% 1.000 Obstructive sleep apnea 9.6% 9.6% 1.000 Chronic anemia 1.3% 1.3% 0.895 Osteoporosis 0.1% 0.2% 0.423 Type 2 diabetes 5.9% 5.6% 0.782 Chronic kidney disease 1.2% 0.9% 0.556 Index hospitalization postoperative complication Postoperative events during the index admission were uncommon overall (Table 2 ). Intraoperative fracture occurred rarely in both groups (0.7% after THA vs 0.6% after HRA; p = 0.743). Blood loss anemia was more frequent after THA (8.9%) than after HRA (5.1%; p = 0.003). Dislocation and acute renal failure were infrequent and did not differ significantly between groups (Table 2 ). In-hospital mortality was not observed in either cohort. Table 2 Index hospitalization postoperative complications (matched cohort) Outcome Total hip arthroplasty (n = 2,844) Hip resurfacing (n = 553) p-value Intraoperative fracture 0.7% 0.6% 0.743 Dislocation 0.2% 0.4% 0.379 Acute renal failure 0.9% 0.4% 0.210 Blood loss anemia 8.9% 5.1% 0.003 Ninety-day readmission and readmission resource utilization All-cause 90-day readmission occurred in 2.7% of THA admissions and 3.1% of HRA admissions, with no statistically significant difference between groups (p = 0.596). Among readmitted patients, the proportion undergoing any inpatient procedure during readmission was low and similar (2.0% vs 2.5%; p = 0.466). Time from discharge to readmission did not differ significantly (32.93 ± 25.12 vs 27.64 ± 18.88 days; p = 0.331). Readmission-level utilization differed, with longer readmission length of stay after THA (5.65 ± 5.23 vs 3.01 ± 3.22 days; p = 0.010) and higher readmission charges after THA ( $ 77,852 ± 68,606 vs $ 44,114 ± 25,112; p = 0.001). Detailed readmission outcomes and resource utilization are presented in Table 3 . Table 3 Ninety-day readmission and readmission resource utilization (matched cohort) Outcome Total hip arthroplasty Hip resurfacing p-value 90-day readmission rate 2.7% 3.1% 0.596 Any inpatient procedure during readmission 2.0% 2.5% 0.466 Days to readmission, days (mean ± SD)* 32.93 ± 25.12 27.64 ± 18.88 0.331 Readmission length of stay, days (mean ± SD)* 5.65 ± 5.23 3.01 ± 3.22 0.010 Readmission total charges, USD (mean ± SD)* 77,852 ± 68,606 44,114 ± 25,112 0.001 Discussion In this contemporary national propensity score-matched analysis of males aged 45–65 years undergoing elective, same-day primary hip arthroplasty, three principal findings emerged. First, index hospitalization charges were higher for HRA than for conventional THA,while length of stay was modestly longer after THA. Differences in perioperative resource utilization between arthroplasty procedures have been described previously, with implant costs, operative workflow, and institutional practice patterns contributing to variations in hospitalization charges and utilization metrics. [11,12] Second, in-hospital adverse events were uncommon in both groups; blood loss anemia occurred more frequently after THA, whereas other selected complications remained rare. Prior comparative analyses have similarly demonstrated low overall complication rates in modern hip arthroplasty populations undergoing elective surgery in optimized perioperative settings. [13] Third, 90-day all-cause readmission rates were low and did not differ significantly between procedures (2.7% after THA vs 3.1% after HRA; p = 0.596). Among patients who were readmitted, however, THA readmissions were associated with greater inpatient resource utilization, reflected by longer readmission length of stay and higher readmission charges Readmission risk: broadly comparable early trajectories in resurfacing-eligible patients A central finding of this study is that early episode-of-care performance-as measured by 90-day inpatient readmission-was similar between HRA and THA in a cohort designed to approximate “resurfacing-eligible” candidates (males, midlife, elective osteoarthritis, procedure on hospital day 0). The absolute readmission difference was small (0.4%) and not statistically significant. Contemporary arthroplasty cohorts have likewise demonstrated relatively low short-term readmission rates in optimized elective THA populations. [14] This is clinically meaningful: patients and surgeons often view HRA as a procedure with unique risk considerations, whereas THA is widely adopted with increasingly streamlined perioperative pathways. Over the past decade, enhanced recovery pathways and outpatient arthroplasty protocols have substantially shortened hospital stays and improved early outcomes in elective hip replacement surgery. [15,16] Our results suggest that, in typical candidates undergoing elective same-day arthroplasty, early readmission risk is broadly comparable between approaches at a national level. Importantly, this finding should be interpreted as evidence of similarity in short-term inpatient readmission rather than equivalence in all clinical outcomes. Resource utilization during readmission: intensity matters, not only counts While readmission rates did not differ significantly, readmission episodes after THA were more resource intensive among those readmitted, with longer inpatient stays and higher charges. This distinction is clinically and economically important because readmission frequency alone may mask heterogeneity in episode severity and treatment intensity. Prior studies examining arthroplasty care episodes have shown that post-discharge healthcare utilization-including emergency department visits, readmissions, and inpatient management intensity-varies considerably depending on complication severity and institutional care pathways. [17] The observed pattern could reflect several non-mutually exclusive mechanisms. First, readmissions after THA in this age-restricted male cohort may more often involve complications requiring prolonged inpatient evaluation or management. Second, residual patient selection differences may remain despite matching. Third, institutional practice patterns and provider volume may influence inpatient resource utilization independent of clinical severity. High-volume arthroplasty centers, for example, have been associated with lower costs and more efficient care delivery in large database analyses. [18] Although our analysis cannot adjudicate these mechanisms, the finding underscores that value-based comparisons should consider the intensity and downstream utilization of readmission episodes, not only their occurrence. Index hospitalization utilization: higher charges for HRA with similar short-stay pathways HRA was associated with higher index hospitalization charges despite slightly shorter length of stay compared with THA. This aligns with pragmatic expectations that implant-related costs, operative time, and operating room resource utilization may differ between procedures in real-world practice. National database studies of hip arthroplasty have demonstrated that implant selection, surgical complexity, and institutional characteristics all contribute to variation in hospitalization charges and resource use. [19] From a counseling perspective, this introduces a clear “value tradeoff” for resurfacing candidates: a potentially higher index-episode financial footprint paired with similar short-term inpatient readmission risk. Because NRD captures billed charges rather than true costs or reimbursements, these findings should be interpreted as proxies for utilization rather than definitive cost-effectiveness. In-hospital events: low overall complication rates in a selected cohort Rates of selected in-hospital postoperative events were low in both cohorts, consistent with the highly selected nature of elective, same-day primary arthroplasty in midlife males. Blood loss anemia was more frequent after THA, which may reflect differences in surgical exposure, intramedullary instrumentation, or perioperative blood management protocols. Previous comparative studies of resurfacing and conventional THA have also reported similar overall complication profiles with small differences in perioperative blood loss depending on surgical technique and perioperative protocols. [20] Other complications such as dislocation, acute renal failure, and intraoperative fracture were rare. The very low event rates-while reassuring clinically-also mean that small absolute differences can appear statistically significant in large datasets or may be sensitive to coding practices. Clinical implications These results support nuanced counseling for resurfacing-eligible patients in several ways. Surgeons can reasonably frame early inpatient readmission risk as low and broadly comparable between HRA and THA in typical candidates. If readmission occurs, the inpatient episode following THA may carry higher utilization, which may be relevant for institutions evaluating bundled-payment performance. The higher index hospitalization charges for HRA highlight the importance of individualized discussion around expected benefits relative to upfront resource use. Limitations This study has limitations inherent to administrative claims data and the NRD design. First, exposure classification and outcome capture depend on ICD-10 coding accuracy; misclassification is possible for both procedure type and postoperative events. Second, NRD lacks granular clinical variables central to resurfacing outcomes, including body mass index as a continuous measure, bone quality metrics, implant manufacturer and bearing design, component positioning, femoral head size, surgical approach, perioperative protocols (e.g., tranexamic acid use), and surgeon/hospital procedure volume. These factors may influence both readmission risk and readmission intensity and could contribute to residual confounding despite excellent matching on measured covariates. Third, the NRD captures inpatient admissions and does not comprehensively capture emergency department visits, observation stays, outpatient encounters, or surveillance-related evaluations-particularly relevant for metal-on-metal-bearing follow-up. Fourth, charge data reflect billed charges rather than true costs and are influenced by hospital-specific accounting and payer structures; thus, they should be interpreted as utilization proxies. Fifth, although matching improved comparability across measured factors, unmeasured selection effects likely persist, especially because HRA is preferentially performed in specialized centers with specific patient selection and expertise. Finally, the analysis was restricted to males aged 45–65 years and elective admissions with surgery on hospital day 0, enhancing clinical comparability but limiting generalizability to females, older patients, non-same-day pathways, or non-osteoarthritis indications. Future directions Future work should evaluate whether the observed similarity in readmission risk and differences in readmission intensity persist across broader cohorts and in settings with additional clinical granularity (registries or linked datasets). Analyses incorporating surgeon and hospital volume, implant design, bearing type, and outpatient utilization would be particularly informative for HRA. Moreover, evaluation of cause-specific readmission diagnoses, reoperation pathways, and longer-term revision endpoints could better connect early episode-of-care performance to durable implant survivorship and patient-centered outcomes. Conclusion Hip resurfacing demonstrated a numerically higher but not statistically significant 90-day readmission rate compared with conventional total hip arthroplasty. Index hospitalization charges were higher for resurfacing, whereas readmission episodes after total hip arthroplasty were associated with longer stays and greater resource utilization. Overall, early episode-of-care outcomes were broadly comparable, supporting the selective use of hip resurfacing in appropriately chosen midlife patients while acknowledging modest differences in resource utilization patterns. Declarations Clinical Trial Number: not applicable Human Ethics and Consent to Participate declarations: The study used de-identified data from the Nationwide Readmissions Database and was deemed exempt from review by the Carmel Medical Center Institutional Review Board. The study was conducted in accordance with the ethical standards of the institutional and national research committee and with the 1964 Declaration of Helsinki and its later amendments. Consent to participate: Informed consent was not required because this study used a de-identified administrative database (Nationwide Readmissions Database). Funding: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Author Contribution DM: Conceptualization, data extraction, statistical analysis, manuscript drafting.YS: Study design, interpretation of results, critical revision.YB: Conceptualization, supervision, manuscript review and editing.All authors approved the final version. Data Availability This study used publicly available data from the HCUP Nationwide Readmissions Database (NRD). Data can be obtained directly from HCUP (https://hcup-us.ahrq.gov/databases.jsp) upon purchase. References Learmonth ID, Young C, Rorabeck C. 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Total hip arthroplasty: 30 days readmission at a tertiary care hospital. Pak J Med Sci. 2025 Apr;41(4):947-951. doi: 10.12669/pjms.41.4.11041. PMID: 40290231; PMCID: PMC12022582. Reisinger L, Cozowicz C, Poeran J, Zhong H, Illescas A, Giannakis P, Liu J, Memtsoudis SG. Trends in comorbidities and complications among patients undergoing elective total hip and knee arthroplasty in the USA. Anaesthesia. 2025 May;80(5):543-550. doi: 10.1111/anae.16529. Epub 2025 Jan 5. PMID: 39756811. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers invited by journal 08 Apr, 2026 Editor invited by journal 31 Mar, 2026 Editor assigned by journal 28 Mar, 2026 Submission checks completed at journal 28 Mar, 2026 First submitted to journal 26 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9233634","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":619975925,"identity":"64212daa-fb79-4bbc-8d9a-16e4966f5a9d","order_by":0,"name":"David Maman","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABAElEQVRIiWNgGAWjYPACZhAyfABkJYDYYMDGTliLscEBFC3M+HRAlJlJgLWgCmIC3fbTiZ8LGKzlDY4zb6v+UGGXZ87OfOwBQ40dAx8OLWZncjdLz2BIN9xwmK3sxoEzycWWzWzpBgzHknE6zOxA7gZpHobDjDObecxuHGw7kLjhMI+ZBAPbAdxazr/d/BuoxR6kpeDgP5iWf3i03MjdBrIlsZ+Zx4zhYANUC2MbPi1vt1nzGKQn9zOzFUucOZYM1MKWJpHYl8yD22G5m2/zVFjbtvEf3vihosYuccP5w8ckPnyzk5Nvb8CuBwwM0AUSGBh48KgfBaNgFIyCUUAAAADewVWsgFz7+QAAAABJRU5ErkJggg==","orcid":"","institution":"Technion Israel Institute of Technology","correspondingAuthor":true,"prefix":"","firstName":"David","middleName":"","lastName":"Maman","suffix":""},{"id":619975926,"identity":"c5865f2a-fa68-4fc4-b810-cc5143162178","order_by":1,"name":"Yaniv Steinfeld","email":"","orcid":"","institution":"Carmel Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Yaniv","middleName":"","lastName":"Steinfeld","suffix":""},{"id":619975927,"identity":"da404607-9fb1-42b3-b53e-5f16f1831973","order_by":2,"name":"Yaron Berkovic","email":"","orcid":"","institution":"Technion Israel Institute of Technology","correspondingAuthor":false,"prefix":"","firstName":"Yaron","middleName":"","lastName":"Berkovic","suffix":""}],"badges":[],"createdAt":"2026-03-26 11:40:27","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9233634/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9233634/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":107480896,"identity":"e2663b42-a77a-4710-8093-73252b968452","added_by":"auto","created_at":"2026-04-22 02:14:16","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":311840,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9233634/v1/61c11325-38be-4c8e-aed9-b19dc9185bbc.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Ninety-Day Readmissions and Resource Utilization After Hip Resurfacing Versus Total Hip Arthroplasty in Patients Aged 45-65 Years: A Propensity Score-Matched Analysis of the Nationwide Readmissions Database","fulltext":[{"header":"Introduction","content":"\u003cp\u003eTotal hip arthroplasty (THA) is among the most successful elective procedures for end-stage hip osteoarthritis, reliably improving pain and function. [1] However, patients in midlife who remain highly active represent a distinct subgroup in which long-term implant durability, return to demanding activity, and preservation of proximal femoral bone stock are particularly important. [2,3] Hip resurfacing arthroplasty (HRA) was reintroduced to address some of these priorities by conserving femoral bone, restoring native hip biomechanics, and using a large-diameter femoral head that may reduce instability risk through increased jump distance. [4,5] In carefully selected patients-most commonly males with primary osteoarthritis and adequate bone quality-contemporary resurfacing systems have demonstrated encouraging survivorship in experienced centers. [6]\u003c/p\u003e \u003cp\u003eAt the same time, resurfacing introduces procedure-specific considerations, particularly those related to metal-on-metal bearings, including adverse local tissue reactions and elevated metal ion levels that may necessitate surveillance and, in some cases, revision. [7,8] While prior comparative work has focused heavily on longer-term survivorship and revision risk, less is known about contemporary short-term episode-of-care outcomes at a national level among typical resurfacing-eligible patients. [3,6] This is clinically relevant because early readmissions and readmission-associated resource use are widely used quality and value metrics and reflect meaningful early postoperative events. [9,10]\u003c/p\u003e \u003cp\u003eUsing a contemporary all-payer national readmissions dataset, we compared elective primary THA versus HRA in a restricted \u0026ldquo;resurfacing-eligible\u0026rdquo; male cohort aged 45\u0026ndash;65 years, emphasizing 90-day readmission, readmission-associated procedures, and readmission resource utilization after 1:5 propensity score matching.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eThis retrospective cohort study used the Nationwide Readmissions Database (NRD) from 2020 through 2022, a Healthcare Cost and Utilization Project (HCUP) dataset that permits linkage of readmissions occurring within the same calendar year. Because the NRD contains de-identified data, this study was deemed exempt from review by the Carmel Medical Center Institutional Review Board. The study was conducted in accordance with the ethical standards of the institutional and national research committee and with the 1964 Declaration of Helsinki and its later amendments. Informed consent was not required because the NRD is a de-identified administrative database.\u003c/p\u003e \u003cp\u003eAdult patients undergoing elective primary hip arthroplasty were identified using ICD-10-PCS procedure coding during the index hospitalization. To reduce heterogeneity in perioperative trajectories and improve comparability between procedure types, the analytic sample was restricted to elective admissions in which the procedure occurred on hospital day 0. Revision procedures, urgent or trauma-related admissions, and discharges carrying COVID-19 diagnosis codes were excluded to reduce confounding by pandemic-related case-mix and care pathways. Records missing essential variables required for propensity score modeling or outcome evaluation were excluded using a complete-case approach.\u003c/p\u003e \u003cp\u003eBecause HRA is predominantly performed in males and female HRA cases were sparse and not clinically comparable within administrative data, the analytic cohort was restricted to males. To further align groups and reduce selection differences by age, the cohort was restricted to patients aged 45\u0026ndash;65 years at admission.\u003c/p\u003e \u003cp\u003eThe exposure was index procedure type, categorized as conventional total hip arthroplasty versus hip resurfacing arthroplasty based on ICD-10-PCS procedure coding during the index admission.\u003c/p\u003e \u003cp\u003eCovariates used for propensity score modeling were selected a priori based on clinical relevance to arthroplasty outcomes and readmission risk. These included age, primary payer, calendar year, residence category (National Center for Health Statistics urban-rural classification), hospital characteristics (region, bed size, and teaching status), and the following comorbidities captured from ICD-10-CM diagnosis coding: obesity, hypertension, dyslipidemia, obstructive sleep apnea, chronic anemia, osteoporosis, type 2 diabetes mellitus, chronic kidney disease, congestive heart failure, and chronic lung disease.\u003c/p\u003e \u003cp\u003eThe primary outcome was all-cause 90-day readmission. Secondary outcomes included index hospitalization resource utilization (length of stay and total hospital charges) and selected in-hospital postoperative events during the index admission (blood loss anemia, intraoperative fracture, dislocation, and acute renal failure). Among patients who were readmitted, readmission resource utilization outcomes included days from discharge to readmission, readmission length of stay, readmission total charges, and whether any inpatient procedure occurred during readmission. The discharge-to-readmission interval was derived by anchoring the NRD timing variable to discharge rather than admission, consistent with standard NRD episode-of-care practice and the analytic approach used in this project.\u003c/p\u003e \u003cp\u003ePropensity scores estimating the likelihood of undergoing HRA were computed using logistic regression including all covariates listed above. Patients were matched 1:5 (HRA:THA) using nearest-neighbor matching without replacement. Covariate balance was assessed using standardized mean differences, with values\u0026thinsp;\u0026lt;\u0026thinsp;0.10 considered indicative of adequate balance. Continuous variables are reported as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation and compared using independent-samples t-tests; when Levene\u0026rsquo;s test suggested unequal variances, Welch\u0026rsquo;s correction was applied. Categorical variables are reported as percentages and compared using chi-square testing or Fisher\u0026rsquo;s exact testing when appropriate. All tests were two-sided with statistical significance set at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05. Analyses were performed in SPSS (IBM).\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eMatched cohort characteristics and index hospitalization utilization\u003c/h2\u003e \u003cp\u003eThe final propensity score-matched cohort included 3,398 elective primary hip arthroplasty admissions among males aged 45\u0026ndash;65 years, comprising 2,844 conventional total hip arthroplasties and 553 hip resurfacings, consistent with the planned 5:1 matching ratio. Post-matching balance was achieved across measured baseline characteristics and comorbidities, with no clinically meaningful residual differences between groups (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eMean age was similar between groups (55.12\u0026thinsp;\u0026plusmn;\u0026thinsp;5.27 years for THA vs 54.83\u0026thinsp;\u0026plusmn;\u0026thinsp;5.29 years for HRA; p\u0026thinsp;=\u0026thinsp;0.241). Index hospitalization charges were higher for HRA (\u003cspan\u003e$\u003c/span\u003e84,555\u0026thinsp;\u0026plusmn;\u0026thinsp;49,002) compared with THA (\u003cspan\u003e$\u003c/span\u003e66,260\u0026thinsp;\u0026plusmn;\u0026thinsp;39,393; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Index length of stay was slightly longer for THA (1.37\u0026thinsp;\u0026plusmn;\u0026thinsp;1.46 days) than for HRA (1.21\u0026thinsp;\u0026plusmn;\u0026thinsp;1.12 days; p\u0026thinsp;=\u0026thinsp;0.018). Calendar year distribution did not differ between groups (p\u0026thinsp;=\u0026thinsp;0.877). Prevalence of matched comorbidities was closely aligned after matching (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMatched cohort characteristics and index hospitalization resource use (age 45\u0026ndash;65 years)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharacteristic\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal hip arthroplasty (n\u0026thinsp;=\u0026thinsp;2,844)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHip resurfacing (n\u0026thinsp;=\u0026thinsp;553)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge, years (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e55.12\u0026thinsp;\u0026plusmn;\u0026thinsp;5.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e54.83\u0026thinsp;\u0026plusmn;\u0026thinsp;5.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.241\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIndex total charges, USD (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e66,260\u0026thinsp;\u0026plusmn;\u0026thinsp;39,393\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e84,555\u0026thinsp;\u0026plusmn;\u0026thinsp;49,002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIndex length of stay, days (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.37\u0026thinsp;\u0026plusmn;\u0026thinsp;1.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.21\u0026thinsp;\u0026plusmn;\u0026thinsp;1.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.018\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCalendar year (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2020.50\u0026thinsp;\u0026plusmn;\u0026thinsp;0.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2020.50\u0026thinsp;\u0026plusmn;\u0026thinsp;0.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.877\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eObesity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34.0%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e34.0%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypertension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e33.1%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e32.7%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.836\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDyslipidemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28.4%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28.5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eObstructive sleep apnea\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.6%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.6%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChronic anemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.3%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.3%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.895\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOsteoporosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.1%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.423\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType 2 diabetes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.9%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.6%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.782\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChronic kidney disease\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.9%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.556\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eIndex hospitalization postoperative complication\u003c/h3\u003e\n\u003cp\u003ePostoperative events during the index admission were uncommon overall (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Intraoperative fracture occurred rarely in both groups (0.7% after THA vs 0.6% after HRA; p\u0026thinsp;=\u0026thinsp;0.743). Blood loss anemia was more frequent after THA (8.9%) than after HRA (5.1%; p\u0026thinsp;=\u0026thinsp;0.003). Dislocation and acute renal failure were infrequent and did not differ significantly between groups (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). In-hospital mortality was not observed in either cohort.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eIndex hospitalization postoperative complications (matched cohort)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOutcome\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal hip arthroplasty (n\u0026thinsp;=\u0026thinsp;2,844)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHip resurfacing (n\u0026thinsp;=\u0026thinsp;553)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIntraoperative fracture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.7%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.6%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.743\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDislocation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.4%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.379\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAcute renal failure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.9%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.4%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.210\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood loss anemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8.9%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5.1%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003eNinety-day readmission and readmission resource utilization\u003c/h3\u003e\n\u003cp\u003eAll-cause 90-day readmission occurred in 2.7% of THA admissions and 3.1% of HRA admissions, with no statistically significant difference between groups (p\u0026thinsp;=\u0026thinsp;0.596). Among readmitted patients, the proportion undergoing any inpatient procedure during readmission was low and similar (2.0% vs 2.5%; p\u0026thinsp;=\u0026thinsp;0.466).\u003c/p\u003e \u003cp\u003eTime from discharge to readmission did not differ significantly (32.93\u0026thinsp;\u0026plusmn;\u0026thinsp;25.12 vs 27.64\u0026thinsp;\u0026plusmn;\u0026thinsp;18.88 days; p\u0026thinsp;=\u0026thinsp;0.331). Readmission-level utilization differed, with longer readmission length of stay after THA (5.65\u0026thinsp;\u0026plusmn;\u0026thinsp;5.23 vs 3.01\u0026thinsp;\u0026plusmn;\u0026thinsp;3.22 days; p\u0026thinsp;=\u0026thinsp;0.010) and higher readmission charges after THA (\u003cspan\u003e$\u003c/span\u003e77,852\u0026thinsp;\u0026plusmn;\u0026thinsp;68,606 vs \u003cspan\u003e$\u003c/span\u003e44,114\u0026thinsp;\u0026plusmn;\u0026thinsp;25,112; p\u0026thinsp;=\u0026thinsp;0.001). Detailed readmission outcomes and resource utilization are presented in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eNinety-day readmission and readmission resource utilization (matched cohort)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOutcome\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal hip arthroplasty\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHip resurfacing\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e90-day readmission rate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.7%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.1%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.596\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAny inpatient procedure during readmission\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.0%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.466\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDays to readmission, days (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e32.93\u0026thinsp;\u0026plusmn;\u0026thinsp;25.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e27.64\u0026thinsp;\u0026plusmn;\u0026thinsp;18.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.331\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReadmission length of stay, days (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.65\u0026thinsp;\u0026plusmn;\u0026thinsp;5.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.01\u0026thinsp;\u0026plusmn;\u0026thinsp;3.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.010\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReadmission total charges, USD (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e77,852\u0026thinsp;\u0026plusmn;\u0026thinsp;68,606\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e44,114\u0026thinsp;\u0026plusmn;\u0026thinsp;25,112\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this contemporary national propensity score-matched analysis of males aged 45\u0026ndash;65 years undergoing elective, same-day primary hip arthroplasty, three principal findings emerged. First, index hospitalization charges were higher for HRA than for conventional THA,while length of stay was modestly longer after THA. Differences in perioperative resource utilization between arthroplasty procedures have been described previously, with implant costs, operative workflow, and institutional practice patterns contributing to variations in hospitalization charges and utilization metrics. [11,12] Second, in-hospital adverse events were uncommon in both groups; blood loss anemia occurred more frequently after THA, whereas other selected complications remained rare. Prior comparative analyses have similarly demonstrated low overall complication rates in modern hip arthroplasty populations undergoing elective surgery in optimized perioperative settings. [13] Third, 90-day all-cause readmission rates were low and did not differ significantly between procedures (2.7% after THA vs 3.1% after HRA; p\u0026thinsp;=\u0026thinsp;0.596). Among patients who were readmitted, however, THA readmissions were associated with greater inpatient resource utilization, reflected by longer readmission length of stay and higher readmission charges\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eReadmission risk: broadly comparable early trajectories in resurfacing-eligible patients\u003c/h2\u003e \u003cp\u003eA central finding of this study is that early episode-of-care performance-as measured by 90-day inpatient readmission-was similar between HRA and THA in a cohort designed to approximate \u0026ldquo;resurfacing-eligible\u0026rdquo; candidates (males, midlife, elective osteoarthritis, procedure on hospital day 0). The absolute readmission difference was small (0.4%) and not statistically significant. Contemporary arthroplasty cohorts have likewise demonstrated relatively low short-term readmission rates in optimized elective THA populations. [14] This is clinically meaningful: patients and surgeons often view HRA as a procedure with unique risk considerations, whereas THA is widely adopted with increasingly streamlined perioperative pathways. Over the past decade, enhanced recovery pathways and outpatient arthroplasty protocols have substantially shortened hospital stays and improved early outcomes in elective hip replacement surgery. [15,16] Our results suggest that, in typical candidates undergoing elective same-day arthroplasty, early readmission risk is broadly comparable between approaches at a national level. Importantly, this finding should be interpreted as evidence of similarity in short-term inpatient readmission rather than equivalence in all clinical outcomes.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eResource utilization during readmission: intensity matters, not only counts\u003c/h3\u003e\n\u003cp\u003eWhile readmission rates did not differ significantly, readmission episodes after THA were more resource intensive among those readmitted, with longer inpatient stays and higher charges. This distinction is clinically and economically important because readmission frequency alone may mask heterogeneity in episode severity and treatment intensity. Prior studies examining arthroplasty care episodes have shown that post-discharge healthcare utilization-including emergency department visits, readmissions, and inpatient management intensity-varies considerably depending on complication severity and institutional care pathways. [17] The observed pattern could reflect several non-mutually exclusive mechanisms. First, readmissions after THA in this age-restricted male cohort may more often involve complications requiring prolonged inpatient evaluation or management. Second, residual patient selection differences may remain despite matching. Third, institutional practice patterns and provider volume may influence inpatient resource utilization independent of clinical severity. High-volume arthroplasty centers, for example, have been associated with lower costs and more efficient care delivery in large database analyses. [18] Although our analysis cannot adjudicate these mechanisms, the finding underscores that value-based comparisons should consider the intensity and downstream utilization of readmission episodes, not only their occurrence.\u003c/p\u003e\n\u003ch3\u003eIndex hospitalization utilization: higher charges for HRA with similar short-stay pathways\u003c/h3\u003e\n\u003cp\u003eHRA was associated with higher index hospitalization charges despite slightly shorter length of stay compared with THA. This aligns with pragmatic expectations that implant-related costs, operative time, and operating room resource utilization may differ between procedures in real-world practice. National database studies of hip arthroplasty have demonstrated that implant selection, surgical complexity, and institutional characteristics all contribute to variation in hospitalization charges and resource use. [19] From a counseling perspective, this introduces a clear \u0026ldquo;value tradeoff\u0026rdquo; for resurfacing candidates: a potentially higher index-episode financial footprint paired with similar short-term inpatient readmission risk. Because NRD captures billed charges rather than true costs or reimbursements, these findings should be interpreted as proxies for utilization rather than definitive cost-effectiveness.\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eIn-hospital events: low overall complication rates in a selected cohort\u003c/h2\u003e \u003cp\u003eRates of selected in-hospital postoperative events were low in both cohorts, consistent with the highly selected nature of elective, same-day primary arthroplasty in midlife males. Blood loss anemia was more frequent after THA, which may reflect differences in surgical exposure, intramedullary instrumentation, or perioperative blood management protocols. Previous comparative studies of resurfacing and conventional THA have also reported similar overall complication profiles with small differences in perioperative blood loss depending on surgical technique and perioperative protocols. [20] Other complications such as dislocation, acute renal failure, and intraoperative fracture were rare. The very low event rates-while reassuring clinically-also mean that small absolute differences can appear statistically significant in large datasets or may be sensitive to coding practices.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eClinical implications\u003c/h2\u003e \u003cp\u003eThese results support nuanced counseling for resurfacing-eligible patients in several ways. Surgeons can reasonably frame early inpatient readmission risk as low and broadly comparable between HRA and THA in typical candidates. If readmission occurs, the inpatient episode following THA may carry higher utilization, which may be relevant for institutions evaluating bundled-payment performance. The higher index hospitalization charges for HRA highlight the importance of individualized discussion around expected benefits relative to upfront resource use.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eLimitations\u003c/h2\u003e \u003cp\u003eThis study has limitations inherent to administrative claims data and the NRD design. First, exposure classification and outcome capture depend on ICD-10 coding accuracy; misclassification is possible for both procedure type and postoperative events. Second, NRD lacks granular clinical variables central to resurfacing outcomes, including body mass index as a continuous measure, bone quality metrics, implant manufacturer and bearing design, component positioning, femoral head size, surgical approach, perioperative protocols (e.g., tranexamic acid use), and surgeon/hospital procedure volume. These factors may influence both readmission risk and readmission intensity and could contribute to residual confounding despite excellent matching on measured covariates. Third, the NRD captures inpatient admissions and does not comprehensively capture emergency department visits, observation stays, outpatient encounters, or surveillance-related evaluations-particularly relevant for metal-on-metal-bearing follow-up. Fourth, charge data reflect billed charges rather than true costs and are influenced by hospital-specific accounting and payer structures; thus, they should be interpreted as utilization proxies. Fifth, although matching improved comparability across measured factors, unmeasured selection effects likely persist, especially because HRA is preferentially performed in specialized centers with specific patient selection and expertise. Finally, the analysis was restricted to males aged 45\u0026ndash;65 years and elective admissions with surgery on hospital day 0, enhancing clinical comparability but limiting generalizability to females, older patients, non-same-day pathways, or non-osteoarthritis indications.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eFuture directions\u003c/h2\u003e \u003cp\u003eFuture work should evaluate whether the observed similarity in readmission risk and differences in readmission intensity persist across broader cohorts and in settings with additional clinical granularity (registries or linked datasets). Analyses incorporating surgeon and hospital volume, implant design, bearing type, and outpatient utilization would be particularly informative for HRA. Moreover, evaluation of cause-specific readmission diagnoses, reoperation pathways, and longer-term revision endpoints could better connect early episode-of-care performance to durable implant survivorship and patient-centered outcomes.\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eHip resurfacing demonstrated a numerically higher but not statistically significant 90-day readmission rate compared with conventional total hip arthroplasty. Index hospitalization charges were higher for resurfacing, whereas readmission episodes after total hip arthroplasty were associated with longer stays and greater resource utilization. Overall, early episode-of-care outcomes were broadly comparable, supporting the selective use of hip resurfacing in appropriately chosen midlife patients while acknowledging modest differences in resource utilization patterns.\u003c/p\u003e "},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eClinical Trial Number:\u003c/strong\u003e not applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHuman Ethics and Consent to Participate declarations:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study used de-identified data from the Nationwide Readmissions Database and was deemed exempt from review by the Carmel Medical Center Institutional Review Board. The study was conducted in accordance with the ethical standards of the institutional and national research committee and with the 1964 Declaration of Helsinki and its later amendments.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInformed consent was not required because this study used a de-identified administrative database (Nationwide Readmissions Database).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDM: Conceptualization, data extraction, statistical analysis, manuscript drafting.YS: Study design, interpretation of results, critical revision.YB: Conceptualization, supervision, manuscript review and editing.All authors approved the final version.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study used publicly available data from the HCUP Nationwide Readmissions Database (NRD). Data can be obtained directly from HCUP (https://hcup-us.ahrq.gov/databases.jsp) upon purchase.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eLearmonth ID, Young C, Rorabeck C. The operation of the century: total hip replacement. Lancet. 2007 Oct 27;370(9597):1508-19. doi: 10.1016/S0140-6736(07)60457-7. PMID: 17964352.\u003c/li\u003e\n\u003cli\u003ePalazzuolo M, Bensa A, Bauer S, Blakeney WG, Filardo G, Riegger M. Resurfacing Hip Arthroplasty Is a Safe and Effective Alternative to Total Hip Arthroplasty in Young Patients: A Systematic Review and Meta-Analysis. J Clin Med. 2023 Mar 7;12(6):2093. doi: 10.3390/jcm12062093. PMID: 36983096; PMCID: PMC10052473.\u003c/li\u003e\n\u003cli\u003eMagan A, Wignadasan W, Kayani B, Radhakrishnan G, Ronca F, Haddad FS. A meta-analysis assessing time for return to sport following hip resurfacing. Arch Orthop Trauma Surg. 2023 Jun;143(6):3575-3585. doi: 10.1007/s00402-022-04592-1. Epub 2022 Aug 30. PMID: 36040530.\u003c/li\u003e\n\u003cli\u003eClough EJ, Clough TM. Metal on metal hip resurfacing arthroplasty: Where are we now? J Orthop. 2020 Dec 31;23:123-127. doi: 10.1016/j.jor.2020.12.036. PMID: 33488008; PMCID: PMC7809170.\u003c/li\u003e\n\u003cli\u003eVan Der Straeten C; and the International Hip Resurfacing Group. Hip resurfacing arthroplasty in young patients: international high-volume centres\u0026apos; report on the outcome of 11,382 metal-on-metal hip resurfacing arthroplasties in patients ⩽50 years at surgery. Hip Int. 2022 May;32(3):353-362. doi: 10.1177/1120700020957354. Epub 2020 Sep 9. PMID: 32905713. \u003c/li\u003e\n\u003cli\u003eVan Der Straeten C; and the International Hip Resurfacing Group. Hip resurfacing arthroplasty in young patients: international high-volume centres\u0026apos; report on the outcome of 11,382 metal-on-metal hip resurfacing arthroplasties in patients ⩽50 years at surgery. Hip Int. 2022 May;32(3):353-362. doi: 10.1177/1120700020957354. Epub 2020 Sep 9. PMID: 32905713.\u003c/li\u003e\n\u003cli\u003eKwon YM, Lombardi AV, Jacobs JJ, Fehring TK, Lewis CG, Cabanela ME. Risk stratification algorithm for management of patients with metal-on-metal hip arthroplasty: consensus statement of the American Association of Hip and Knee Surgeons, the American Academy of Orthopaedic Surgeons, and the Hip Society. J Bone Joint Surg Am. 2014 Jan 1;96(1):e4. doi: 10.2106/JBJS.M.00160. PMID: 24382732.\u003c/li\u003e\n\u003cli\u003eXiong L, Smith EJ, Klemt C, Barghi A, Padmanabha A, Kwon YM. MRI Characteristics of Adverse Local Tissue Reactions Associated With Intraoperative Tissue Damage and Poor Revision Surgery Outcomes: A Systematic Review. J Am Acad Orthop Surg. 2021 Oct 15;29(20):e1025-e1033. doi: 10.5435/JAAOS-D-20-00793. PMID: 33201043.\u003c/li\u003e\n\u003cli\u003eChen XT, Christ AB, Chung BC, Ton A, Ballatori AM, Shahrestani S, Gettleman BS, Heckmann ND. Cemented versus Cementless Femoral Fixation for Elective Primary Total Hip Arthroplasty: A Nationwide Analysis of Short-Term Complication and Readmission Rates. J Clin Med. 2023 Jun 9;12(12):3945. doi: 10.3390/jcm12123945. PMID: 37373640; PMCID: PMC10299501.\u003c/li\u003e\n\u003cli\u003eAli AM, Loeffler MD, Aylin P, Bottle A. Factors Associated With 30-Day Readmission After Primary Total Hip Arthroplasty: Analysis of 514 455 Procedures in the UK National Health Service. JAMA Surg. 2017 Dec 20;152(12):e173949. doi: 10.1001/jamasurg.2017.3949. Epub 2017 Dec 20. Erratum in: JAMA Surg. 2017 Dec 1;152(12):1184. doi: 10.1001/jamasurg.2017.4857. PMID: 28979994; PMCID: PMC5831438.\u003c/li\u003e\n\u003cli\u003eHuang Y, Yang Q, Wang Z, Pan Z, Zhang Y, Shi Z, Yang S. Comparisons of in-hospital complications between total hip arthroplasty and hip resurfacing arthroplasty. BMC Musculoskelet Disord. 2023 May 11;24(1):375. doi: 10.1186/s12891-023-06487-7. PMID: 37170240; PMCID: PMC10173641.\u003c/li\u003e\n\u003cli\u003eHanreich C, Su E, Cororaton A, Lyman S, Jungwirth-Weinberger A, Boettner F. Hip resurfacing and posterior approach total hip arthroplasty have equivalent blood loss when tranexamic acid is used: a propensity score matched cohort analysis. Arch Orthop Trauma Surg. 2022 Dec;142(12):4055-4061. doi: 10.1007/s00402-021-04272-6. Epub 2022 Jan 10. PMID: 35001154.\u003c/li\u003e\n\u003cli\u003eNg MK, Fong AM, Chen Z, Gordon A, Magruder M, Bains SS, Dubin JA, Hameed D, Wong CHJ, Mont MA. Sex-Specific Postoperative Outcomes of Primary Total Hip Replacements: The Performance of Total Hip Replacement Procedures Leads to Worse Outcomes in Men. Surg Technol Int. 2023 Sep 15;42:329-333. doi: 10.52198/23.STI.42.OS1687. PMID: 37466923.\u003c/li\u003e\n\u003cli\u003eRichardson MK, Wier J, Liu KC, Mayfield CK, Vega AN, Lieberman JR, Heckmann ND. 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PMID: 36342359; PMCID: PMC10097563.\u003c/li\u003e\n\u003cli\u003eDeMik DE, Carender CN, Glass NA, Callaghan JJ, Bedard NA. Home Discharge Has Increased After Total Hip Arthroplasty, However Rates Vary Between Large Databases. J Arthroplasty. 2021 Feb;36(2):586-592.e1. doi: 10.1016/j.arth.2020.08.039. Epub 2020 Aug 25. PMID: 32917463; PMCID: PMC7445154.\u003c/li\u003e\n\u003cli\u003eKarimi AH, Grits D, Shah AK, Burkhart RJ, Kamath AF. Is Discharge Within a Day Following Total Hip Arthroplasty Safe in the Septuagenarian and Octogenarian Population? A Propensity-Matched Cohort Study. J Arthroplasty. 2024 Jan;39(1):13-18. doi: 10.1016/j.arth.2023.08.065. Epub 2023 Aug 23. PMID: 37625466.\u003c/li\u003e\n\u003cli\u003eFarooq MO, Tariq M, Sulaiman A, Noordin S. Total hip arthroplasty: 30 days readmission at a tertiary care hospital. Pak J Med Sci. 2025 Apr;41(4):947-951. doi: 10.12669/pjms.41.4.11041. PMID: 40290231; PMCID: PMC12022582.\u003c/li\u003e\n\u003cli\u003eReisinger L, Cozowicz C, Poeran J, Zhong H, Illescas A, Giannakis P, Liu J, Memtsoudis SG. Trends in comorbidities and complications among patients undergoing elective total hip and knee arthroplasty in the USA. Anaesthesia. 2025 May;80(5):543-550. doi: 10.1111/anae.16529. Epub 2025 Jan 5. PMID: 39756811.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bsur","sideBox":"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bsur/default.aspx","title":"BMC Surgery","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"hip resurfacing, total hip arthroplasty, Nationwide Readmissions Database, propensity score matching, 90-day readmission, resource utilization, charges, length of stay","lastPublishedDoi":"10.21203/rs.3.rs-9233634/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9233634/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eHip resurfacing arthroplasty (HRA) is selectively used for younger, active patients with hip osteoarthritis as a bone-preserving alternative to conventional total hip arthroplasty (THA). Contemporary national data comparing short-term, episode-of-care outcomes-including 90-day readmission and readmission resource utilization-remain limited in typical resurfacing-eligible patients.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eWe performed a retrospective cohort study using the Nationwide Readmissions Database (NRD), 2020\u0026ndash;2022. Elective, osteoarthritis-related primary hip arthroplasty admissions with the procedure performed on hospital day 0 were identified. The analytic cohort was restricted to males aged 45\u0026ndash;65 years. Patients undergoing HRA were compared with those undergoing THA using 1:5 nearest-neighbor propensity score matching without replacement, incorporating demographics, payer, calendar year, residence category, hospital characteristics, and comorbidities (obesity, hypertension, dyslipidemia, obstructive sleep apnea, chronic anemia, osteoporosis, type 2 diabetes mellitus, chronic kidney disease, congestive heart failure, and chronic lung disease). The primary endpoint was all-cause 90-day readmission. Secondary outcomes included index hospitalization length of stay and charges, selected in-hospital complications, and readmission-level utilization among readmitted patients.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe matched cohort included 3,398 admissions (THA n\u0026thinsp;=\u0026thinsp;2,844; HRA n\u0026thinsp;=\u0026thinsp;553). Baseline balance was achieved after matching. Index hospitalization charges were higher for HRA (\u003cspan\u003e$\u003c/span\u003e84,555\u0026thinsp;\u0026plusmn;\u0026thinsp;49,002) than THA (\u003cspan\u003e$\u003c/span\u003e66,260\u0026thinsp;\u0026plusmn;\u0026thinsp;39,393; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), while index length of stay was slightly longer after THA (1.37\u0026thinsp;\u0026plusmn;\u0026thinsp;1.46 vs 1.21\u0026thinsp;\u0026plusmn;\u0026thinsp;1.12 days; p\u0026thinsp;=\u0026thinsp;0.018). In-hospital mortality was not observed. Blood loss anemia occurred more frequently after THA (8.9% vs 5.1%; p\u0026thinsp;=\u0026thinsp;0.003). Ninety-day readmission occurred in 2.7% after THA and 3.1% after HRA, with no statistically significant difference (p\u0026thinsp;=\u0026thinsp;0.596). Among readmitted patients, readmission length of stay (5.65\u0026thinsp;\u0026plusmn;\u0026thinsp;5.23 vs 3.01\u0026thinsp;\u0026plusmn;\u0026thinsp;3.22 days; p\u0026thinsp;=\u0026thinsp;0.010) and charges (\u003cspan\u003e$\u003c/span\u003e77,852\u0026thinsp;\u0026plusmn;\u0026thinsp;68,606 vs \u003cspan\u003e$\u003c/span\u003e44,114\u0026thinsp;\u0026plusmn;\u0026thinsp;25,112; p\u0026thinsp;=\u0026thinsp;0.001) were higher after THA, while time to readmission and the proportion with any inpatient procedure during readmission were similar.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eIn males aged 45\u0026ndash;65 years undergoing elective, same-day primary hip arthroplasty, HRA was associated with higher index hospitalization charges but similar 90-day readmission rates compared with THA. Among patients who were readmitted, THA was associated with greater readmission resource utilization. These findings provide contemporary national episode-of-care benchmarks and support nuanced, value-informed counseling in appropriately selected candidates.\u003c/p\u003e\u003ch2\u003eLevels of Evidence:\u003c/h2\u003e \u003cp\u003eLevel III\u003c/p\u003e","manuscriptTitle":"Ninety-Day Readmissions and Resource Utilization After Hip Resurfacing Versus Total Hip Arthroplasty in Patients Aged 45-65 Years: A Propensity Score-Matched Analysis of the Nationwide Readmissions Database","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-16 17:05:12","doi":"10.21203/rs.3.rs-9233634/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewersInvited","content":"","date":"2026-04-09T02:33:58+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-03-31T09:07:21+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-28T06:30:45+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-28T06:30:21+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Surgery","date":"2026-03-26T11:23:16+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bsur","sideBox":"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bsur/default.aspx","title":"BMC Surgery","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"99a92ae5-fc7c-40b4-95a4-67c4c429b118","owner":[],"postedDate":"April 16th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-16T17:05:12+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-16 17:05:12","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9233634","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9233634","identity":"rs-9233634","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}