Concentrated Economic Disadvantage Predicts Resource Utilization After Total Knee Arthroplasty.

BACKGROUND: The Index of Concentration at the Extremes (ICE), a measure of geographic socioeconomic polarization, predicts several health outcomes but has not been evaluated concerning total knee arthroplasty (TKA). This study evaluates ICE as a predictor of post-TKA resource utilization. METHODS: Using the Healthcare Cost and Utilization Project's New York State database from 2016 to 2017, we retrospectively evaluated 57,426 patients ≥50 years undergoing primary TKA. The ICE values for extreme concentrations of income and race were calculated using United States Census Bureau data with the formula ICEi = (Pi-Di)/Ti where Pi, Di, and Ti are the number of households in the most privileged extreme, disadvantaged extreme, and total population in zip code i, respectively. Extremes of privilege and disadvantage were defined as ≥$150,000 versus <$25,000 for income and non-Hispanic White versus non-Hispanic Black for race. Association of ICE values, demographics, and comorbidities with 90-day readmission and 90-day emergency department (ED) visits was examined using multivariable analysis. RESULTS: Overall 90-day readmission and ED visit rates were 12.8% and 9.4%, respectively. On multivariable analysis, the lowest ICEIncome quintile (concentrated poverty) predicted 90-day readmission (odds ratio 1.17, 95% confidence interval 1.05 to 1.30, P = .005) and 90-day ED visit (odds ratio 1.22, 95% confidence interval 1.08 to 1.38, P = .001). The ICERace was not predictive of either outcome. CONCLUSION: Patients in communities with the lowest ICEIncome values use more inpatient and ED resources after primary TKA. Incorporating ICEIncome into risk-adjusted payment models may help align incentives for equitable care.

Risk Should Not Be a "Four-Letter Word" in Healthcare. Risk and the Future of Musculoskeletal Care.

Orthopaedics has seen a rapid transition to value-based care. As we transition away from fee-for-service models, healthcare systems, groups, and surgeons are being asked to take on an increasing amount of risk. While on the surface risk may have a negative connotation, managing risk allows surgeons to maintain autonomy while taking on value-based care to the next level. The purpose of this paper, the first in a series of 2, is to walk through the impact that value-based care has had on musculoskeletal surgeons, to understand the continued movement healthcare is making into risk sharing models, and to introduce the concept of surgeon specialist-led care.

Assessment of Team Dynamics and Operative Efficiency in Hip and Knee Arthroplasty.

Importance: Surgical team communication is a critical component of operative efficiency. The factors underlying optimal communication, including team turnover, role composition, and mutual familiarity, remain underinvestigated in the operating room. Objective: To assess staff turnover, trainee involvement, and surgeon staff preferences in terms of intraoperative efficiency. Design, Setting, and Participants: Retrospective analysis of staff characteristics and operating times for all total joint arthroplasties was performed at a tertiary academic medical center by 5 surgeons from January 1 to December 31, 2018. Data were analyzed from May 1, 2021, to February 18, 2022. The study included cases with primary total hip arthroplasties (THAs) and primary total knee arthroplasties (TKAs) comprising all primary total joint arthroplasties performed over the 1-year study interval. Exposures: Intraoperative turnover among nonsurgical staff, presence of trainees, and presence of surgeon-preferred staff. Main Outcomes and Measures: Incision time, procedure time, and room time for each surgery. Multivariable regression analyses between operative duration, presence of surgeon-preferred staff, and turnover among nonsurgical personnel were conducted. Results: A total of 641 cases, including 279 THAs (51% female; median age, 64 [IQR, 56.3-71.5] years) and 362 TKAs (66% [238] female; median age, 68 [IQR, 61.1-74.1] years) were considered. Turnover among circulating nurses was associated with a significant increase in operative duration in both THAs and TKAs, with estimated differences of 19.6 minutes (SE, 3.5; P < .001) of room time in THAs and 14.0 minutes (SE, 3.1; P < .001) of room time in TKAs. The presence of a preferred anesthesiologist or surgical technician was associated with significant decreases of 26.5 minutes (SE, 8.8; P = .003) of procedure time and 12.6 minutes (SE, 4.0; P = .002) of room time, respectively, in TKAs. The presence of a surgeon-preferred vendor was associated with a significant increase in operative duration in both THAs (26.3 minutes; SE, 7.3; P < .001) and TKAs (29.6 minutes; SE, 9.6; P = .002). Conclusions and Relevance: This study found that turnover among operative staff is associated with procedural inefficiency. In contrast, the presence of surgeon-preferred staff may facilitate intraoperative efficiency. Administrative or technologic support of perioperative communication and team continuity may help improve operative efficiency.

Effects of Hospital and Surgeon Volume on Patient Outcomes After Total Joint Arthroplasty: Reported From the American Joint Replacement Registry.

BACKGROUND: The purpose of this study was to evaluate outcomes and complications because it relates to surgeon and hospital volume for patients undergoing primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) using the American Joint Replacement Registry from 2012 to 2017. METHODS: A retrospective study was conducted on Medicare-eligible cases of primary elective THAs and TKAs reported to the American Joint Replacement Registry database and was linked with the available Centers of Medicaid and Medicare Services claims and the National Death Index data from 2012 to 2017. Surgeon and hospital volume were defined separately based on the median annual number of anatomic-specific total arthroplasty procedures performed on patients of any age per surgeon and per hospital. Values were aggregated into separate surgeon and hospital volume tertile groupings and combined to create pairwise comparison surgeon/hospital volume groupings for hip and knee. RESULTS: Adjusted multivariable logistic regression analysis found low surgeon/low hospital volume to have the greatest association with all-cause revisions after THA (odds ratio [OR], 1.63, 95% confidence interval [CI], 1.41-1.89, P < 0.0001) and TKA (OR, 1.72, 95% CI, 1.44-2.06, P < 0.0001), early revisions because of periprosthetic joint infection after THA (OR, 2.50, 95% CI, 1.53-3.15, P < 0.0001) and TKA (OR, 2.18, 95% CI, 1.64-2.89, P < 0.0001), risk of early THA instability and dislocation (OR, 2.47, 95% CI, 1.77-3.46, P < 0.0001), and 90-day mortality after THA (OR, 1.72, 95% CI, 1.27-2.35, P = 0.0005) and TKA (OR, 1.47, 95% CI, 1.15-1.86, P = 0.002). CONCLUSION: Our findings demonstrate considerably greater THA and TKA complications when performed at low-volume hospitals by low-volume surgeons. Given the data from previous literature including this study, a continued push through healthcare policies and healthcare systems is warranted to direct THA and TKA procedures to high-volume centers by high-volume surgeons because of the evident decrease in complications and considerable costs associated with all-cause revisions, periprosthetic joint infection, instability, and 90-day mortality. LEVEL OF EVIDENCE: III.

Caring for Diverse and High-Risk Patients: Surgeon, Health System, and Patient Integration.

Access and outcome disparities exist in hip and knee arthroplasty care. These disparities are associated with race, ethnicity, and social determinants of health such as income, housing, transportation, education, language, and health literacy. Additionally, medical comorbidities affecting postoperative outcomes are more prevalent in underresourced communities, which are more commonly communities of color. Navigating racial and ethnic differences in treating our patients undergoing hip and knee arthroplasty is necessary to reduce inequitable care. It is important to recognize our implicit biases and lessen their influence on our healthcare decision-making. Social determinants of health need to be addressed on a large scale as the current inequitable system disproportionally impacts communities of color. Patients with lower health literacy have a higher risk of postoperative complications and poor outcomes after hip and knee replacement. Low health literacy can be addressed by improving communication, reducing barriers to care, and supporting patients in their efforts to improve their own health. High-risk patients require more financial, physical, and mental resources to care for them, and hospitals, surgeons, and health insurance companies are often disincentivized to do so. By advocating for alternative payment models that adjust for the increased risk and take into account the increased perioperative work needed to care for these patients, surgeons can help reduce inequities in access to care. We have a responsibility to our patients to recognize and address social determinants of health, improve the diversity of our workforce, and advocate for improved access to care to decrease inequity and outcomes disparities in our field.

Cementless Fixation Is Associated With Increased Risk of Early and All-Time Revision After Hemiarthroplasty But Not After THA for Femoral Neck Fracture: Results From the American Joint Replacement Registry.

BACKGROUND: Despite ample evidence supporting cemented femoral fixation for both hemiarthroplasty and THA for surgical treatment of displaced femoral neck fractures, cementless fixation is the preferred fixation method in the United States. To our knowledge, no nationally representative registry from the United States has compared revision rates by fixation for this surgical treatment. QUESTION/PURPOSE: After controlling for relevant confounding variables, is femoral fixation method (cemented or cementless) in hemiarthroplasty or THA for femoral neck fracture associated with a greater risk of (1) all-cause revision or (2) revision for periprosthetic fracture? METHODS: Patients with Medicare insurance who had femoral neck fractures treated with hemiarthroplasty or THA reported in the American Joint Replacement Registry database from 2012 to 2017 and Centers for Medicare and Medicaid Services claims data from 2012 to 2017 were analyzed in this retrospective, large-database study. Of the 37,201 hemiarthroplasties, 42% (15,748) used cemented fixation and 58% (21,453) used cementless fixation. Of the 7732 THAs, 20% (1511) used cemented stem fixation and 80% (6221) used cementless stem fixation. For both the hemiarthroplasty and THA cohorts, most patients were women and had cementless femoral fixation. Early revision was defined as a procedure that occurred less than 90 days from the index procedure. All patients submitted to the registry were included in the analysis. Patient follow-up was limited to the study period. No patients were lost to follow-up. Due to inherent limitations with the registry, we did not compare medical complications, including deaths attributed directly to cemented fixation. A logistic regression model including the index arthroplasty, age, gender, stem fixation method, hospital size, hospital teaching affiliation, and Charlson comorbidity index score was used to determine associations between the index procedure and revision rates. RESULTS: For the hemiarthroplasty cohort, risk factors for any revision were cementless stem fixation (odds ratio 1.42 [95% confidence interval 1.20 to 1.68]; p < 0.001), younger age (OR 0.96 [95% CI 0.95 to 0.97]; p < 0.001), and higher Charlson comorbidity index (OR 1.06 [95% CI 1.02 to 1.11]; p = 0.004). Risk factors for early revision were cementless stem fixation (OR 1.77 [95% CI 1.43 to 2.20]; p < 0.001), younger age (OR 0.98 [95% CI 0.97 to 0.99]; p < 0.001), and higher Charlson comorbidity index (OR 1.09 [95% CI 1.04 to 1.15]; p < 0.001). Risk factors for revision due to periprosthetic fracture were cementless fixation (OR 6.19 [95% CI 3.08 to 12.42]; p < 0.001) and higher Charlson comorbidity index (OR 1.16 [95% CI 1.06 to 1.28]; p = 0.002). Risk factors for early revision due to periprosthetic fracture were cementless fixation (OR 7.38 [95% CI 3.17 to 17.17]; p < 0.001), major teaching hospital (OR 2.10 [95% CI 1.08 to 4.10]; p = 0.03), and higher Charlson comorbidity index (OR 1.20 [95% CI 1.09 to 1.33]; p < 0.001). For the THA cohort, there were no associations. CONCLUSION: These data suggest that cemented fixation should be the preferred technique for most patients with displaced femoral neck fractures treated with hemiarthroplasty. The fact that stem fixation method did not affect revision rates for those patients with displaced femoral neck fractures treated with THA may be due to current practice patterns in the United States. LEVEL OF EVIDENCE: Level III, therapeutic study.

Migration Patterns for Revision Total Knee Arthroplasty in the United States as Reported in the American Joint Replacement Registry.

BACKGROUND: Revision total knee arthroplasty (TKA) is associated with a higher complication rate and a greater cost when compared to primary TKA. Based on patient choice, referral, or patient transfers, revision TKAs are often performed in different institutions by different surgeons than the primary TKA. The aim of this study is to evaluate the effect of hospital size, teaching status, and revision indication on the migration patterns of failed primary TKA in patients 65 years of age and older. METHODS: All primary and revision TKAs reported to the American Joint Replacement Registry from January 2012 through March 2020 were included and merged with the Centers for Medicare and Medicaid Services database. Migration was defined as a patient having a primary TKA and revision TKA performed at separate institutions by different surgeons. RESULTS: In total, 9167 linked primary and revision TKAs were included in the analysis. Overall migration rates were significantly higher from small (<100 beds; P = .019), non-teaching institutions (P = .002) driven primarily by patients diagnosed with infection. Infection patients had significantly higher migration rates from small (46.8%, P < .001), non-teaching (43.5%, P < .001) institutions, while migration rates for other causes of revision were statistically similar. Most patients migrated to medium or large institutions (84.7%) for revision TKA rather than small institutions (15.3%, P < .001) and to teaching (78.3%) rather than non-teaching institutions (21.7%, P < .001). CONCLUSION: There is a diagnosis-dependent referral bias that affects the migration rates of infected primary TKA from small non-teaching institutions leading to a flow of more medically complex patients to medium and large teaching institutions for infected revision TKA.

Provider Personal and Demographic Characteristics and Patient Satisfaction in Orthopaedic Surgery.

INTRODUCTION: Patient satisfaction has increasingly been used to assess physician performance and quality of care. Although there is evidence that patient satisfaction is associated with patient-reported health outcomes and communication-related measures, there is debate over the use of patient satisfaction in reimbursement policy. Patient characteristics that influence satisfaction have been studied, but the effects of personal and demographic characteristics of physicians on patient satisfaction have yet to be explored. METHODS: Outpatient satisfaction scores from 11,059 patients who rated 25 orthopaedic surgeons from a single institution were studied. In this study, we sought to explore the relationship between nonmodifiable physician characteristics, such as sex and race, and patient satisfaction with outpatient orthopaedic surgery care, as expressed in the Press Ganey Satisfaction Scores. Univariate logistic regression models were used to test the associations between each provider characteristic and patient satisfaction on the Press Ganey patient satisfaction questionnaire. RESULTS: Three nonmodifiable physician personal and demographic characteristics were markedly associated with lower patient satisfaction scores across overall satisfaction, communication, and empathy domains: (1) female gender, (2) Asian ethnicity, and (3) being unmarried. Asian ethnicity reduced the odds of receiving a 5-star rating for likelihood to recommend the provider by nearly 40%, but none of these nonmodifiable physician personal and demographic characteristics affected the likelihood to recommend the practice. DISCUSSION: Sex, ethnicity, and marital status are nonmodifiable provider characteristics, each associated with markedly lower odds of receiving a 5-star rating on Press Ganey patient satisfaction survey. These data reveal inherent patient biases that negatively affect physician-patient interactions and may exacerbate the lack of diversity in orthopaedic surgery. More research is necessary before using patient satisfaction ratings to evaluate surgeons or as quality measures that affect reimbursement policies.

The Removal of Total Hip and Total Knee Arthroplasty From the Inpatient-Only List Increases the Administrative Burden of Surgeons and Continues to Cause Confusion.

BACKGROUND: Several studies have shown that the removal of total knee arthroplasty (TKA) from the Centers for Medicare and Medicaid Services (CMS) inpatient-only (IPO) list has caused confusion among surgeons, hospitals, and patients. The purpose of this study is to determine whether similar confusion was present after CMS recently removed total hip arthroplasty (THA) from the IPO list. METHODS: We surveyed the American Association of Hip and Knee Surgeons membership via an online web-based questionnaire in February 2020. The 12-question form asked about practice type and the impact that having both THA and TKA removed from the IPO list has had on each surgeon's practice. Responses were tabulated and descriptive statistics of each question reported. RESULTS: Of the 2847 American Association of Hip and Knee Surgeons members surveyed, 419 responded (14.7% response rate). Three hundred forty-one surgeons (81%) stated that changes to IPO status have increased their practice's administrative burden. Fifty-four percent of surgeons reported that they have needed to obtain preauthorization or appeal a denial of preauthorization for an inpatient total joint arthroplasty at least monthly, while 257 surgeons (61%) have had patients contact their office regarding an unexpected copayment. Despite the commitment of CMS to waiving certain audits for 2 years, 43 respondents (10%) stated they had undergone an audit regarding a patient's inpatient status. CONCLUSION: The removal of THA and TKA from the IPO list continues to be an administrative burden for arthroplasty surgeons and a source of confusion among patients. CMS should provide additional guidance to address surgeons' concerns about preauthorization for inpatient stays, unexpected patient copayments, and CMS audits.

Total Knee Replacement: The Inpatient-Only List and the Two Midnight Rule, Patient Impact, Length of Stay, Compliance Solutions, Audits, and Economic Consequences.

BACKGROUND: In November 2017, CMS finalized the 2018 Medicare Outpatient Prospective Payment System rule that removed TKA from the Medicare inpatient-only (IPO) list. This action had significant and unexpected consequences. METHODS: We looked at 3 levels of the IPO rule impact on TKA for Medicare beneficiaries: a national comparison of FFS inpatient and outpatient classification for 2017 vs 2018; a survey of AAHKS surgeons completed in April 2019; and an in-depth analysis of a large academic medical center experience. An analysis of change in admission classification of patients with TKA over time, number of QIO audits, compliance solutions for the new rule, and cost implications of those compliance solutions were evaluated. RESULTS: Hospital reimbursement averages $10,122 in an outpatient facility but does not include the physician payment. Average hospital reimbursement in the inpatient setting is $11,760. The difference in hospital reimbursement varies widely (90th percentile decrease, $6725 vs 10th percentile $2048). Physician payments are the same in both settings (avg $1403). Patients with TKA not designated for inpatient admissions are not eligible for bundle payment programs. Patients designated as outpatients are subjected to higher out-of-pocket expenses. Patients may have an annual Medicare Part B Deductible ($185) and a 20% copay as well as prescription and durable medical equipment costs. An AAHKS survey demonstrated that 45.08% were with inpatient designation only, 17.62% were with outpatient designation only, 25.39% were designated as necessary, and 10.1% were designated by the hospital. This survey showed that 66 of 374 (17.65%) patients had undergone a QIO audit as a result of issues with the IPO rule. An evaluation of an AMC demonstrated that since January 1, 2018, 470 of 690 (68.1%) of CMS patients with TKA left in less than 2 midnights. The institution was subjected to 2 QIO audits. CONCLUSIONS: There are many unintended consequences to the IPO rule application to TKA.

Quantifying Surgeon Work in Total Hip and Knee Arthroplasty: Where Do We Stand Today?

BACKGROUND: Physician work is a critical component in determining reimbursement for total joint arthroplasty (TJA). The purpose of this study is to quantify the time spent during the different phases of TJA care relative to the benchmarks used by the Centers for Medicare and Medicaid Services. METHODS: We retrospectively reviewed all patients captured in our institutional joint database between January 1, 2014, and December 31, 2018. Four phases of care were assessed: (1) preoperative period following the decision to proceed with TJA and leading to the day before surgery, (2) immediate 24 hours preceding surgery (preservice time), (3) operative time from skin incision to dressing application (intraservice time), and (4) postoperative work including day of surgery and the following 90 days. RESULTS: A total of 666 procedures were analyzed (379 total hip arthroplasties and 287 total knee arthroplasties). The mean preoperative care coordination, preservice, intraservice, immediate postservice, and 91-day global period times were 21.9 ± 10, 84.1, 114 ± 24, 35, and 150 ± 37 minutes, respectively. Except for a slightly higher preoperative time associated with Medicare coverage (P = .031), there were no differences in the other phases of care by payer type. There were no temporal differences between 2014 and 2017. However, in 2018, there were significant increases in preoperative and intraservice times (6 and 20 minutes, respectively, P < .001) which were accompanied with a significant decrease in postoperative service time (34 minutes, P < .001). CONCLUSION: Even when performing TJA under the most optimal conditions, the overall time has remained stable over the past 5 years and consistent with current benchmarks.

The Cost of Malnutrition in Total Joint Arthroplasty.

BACKGROUND: Malnutrition is a known risk factor for complications and adverse outcomes after elective total joint arthroplasty (TJA), but little is known about the burden this risk factor places on the healthcare system. The purpose of this study was to evaluate the 90-day impact of malnutrition on medical and surgical complications and understand the increase in global reimbursements associated with TJA in malnourished patients. METHODS: We queried a combined private-payer and Medicare database from 2007 to 2016 for TJA using International Classification of Diseases, 9th revision and Current Procedural Terminology codes. Patients with serum albumin level of <3.5 g/dL were gender, age, and mean Elixhauser Comorbidity Index matched against a cohort with a normal serum albumin level. Odds ratios and confidence intervals were calculated for complications at 90 days postoperatively. Mean index and 90-day global reimbursements were calculated for the two matched groups and compared using P-values. RESULTS: 3053 protein malnourished patients receiving TJA were identified, and 12,202 matched protein nourished patients receiving TJA served as controls. At 90 days, the malnourished groups had increased risk for failure of multiple organ systems, periprosthetic joint infection, and reoperation. The mean 90-day increase in reimbursement was $3875 associated with performing a TJA on a protein malnourished patient (P < .001). CONCLUSION: This study demonstrates an association between malnourished patients and postoperative complications as well as significantly increased reimbursements. Understanding the reimbursement increases at 90 days for TJA in protein malnourished patients is important in the era of bundled payments.

Computer Navigation vs Conventional Total Hip Arthroplasty: A Medicare Database Analysis.

BACKGROUND: Computer-assisted surgery (CAS) is applied to total hip arthroplasty (THA) in an attempt to optimize implant positioning. The effect of CAS on postoperative complications after THA remains unknown. Our study aims to assess the change in complication rates when CAS is used in THA. METHODS: The Medicare database was studied from 2005 to 2012. All THAs performed with CAS were identified. A total of 64,944 THAs were identified, including 5412 CAS-THAs and 59,532 conventional THAs. Medical and surgical adverse events were collected at various time points. RESULTS: CAS-THA was not associated with a decreased rate of dislocation at 30 days (1.0% vs 1.2%; odds ratio [OR], 1.14; P = .310), 90 days (1.1% vs 1.4%; OR, 1.23; P = .090), or 2 years (2.3% vs 2.3%; OR, 1.01; P = .931). CAS-THA was associated with a significantly higher rate of periprosthetic fracture at 30 days (0.4% vs 0.6%; OR, 1.46; P = .040) as well as revision THA at 30 days (1.0% vs 1.4%; OR, 1.43; P = .003) and 90 days (1.2% vs 1.7%; OR, 1.42; P < .002) when compared to conventional THA. CAS-THA was associated with a significantly lower rate of deep vein thrombosis and pulmonary embolism when compared to conventional THA at all time points (P < .05). CONCLUSION: Administrative coding data fail to demonstrate any clinically significant reduction in short-term adverse events with CAS-THA. Further study is warranted to evaluate whether the purported benefits of CAS result in a reduction of the adverse events after THA.

The Unintended Impact of the Removal of Total Knee Arthroplasty From the Center for Medicare and Medicaid Services Inpatient-Only List.

BACKGROUND: Total knee arthroplasty (TKA) was removed from the Centers for Medicare and Medicaid Services (CMS) Inpatient-Only (IPO) list starting January 1, 2018. Many hospitals responded by instructing surgeons to schedule all TKAs as outpatient procedures, and some local Medicare Advantage contractors began to expect outpatient status for all or most TKA cases. This activity and ensuing confusion has caused considerable unintended disruption for surgeons, hospitals, and patients. The purpose of this study was to gauge the impact on providers and patients. METHODS: Active members of the American Association of Hip and Knee Surgeons were sent a 9-question survey asking if the surgeon's hospital was treating all patients undergoing TKA as outpatients and if Medicare Advantage administrators and commercial payers were treating all or most the same. Questions also inquired about the impact on surgeon practices and their patients. RESULTS: Seven hundred thirty members (26%) responded; of which, 59.5% reported that their hospitals have instructed them that all Medicare TKAs should be scheduled as outpatient procedures; 40.5% have been asked to use proscribed documentation to justify that change; 30.4% reported that their patients have incurred added personal cost secondary to their surgical procedure being billed as an outpatient procedure; and 76.1% report that this issue has become an administrative burden. CONCLUSION: The CMS clearly stated its expectation in the 2018 Outpatient Prospective Payment System Final Rule that the great majority of Medicare fee-for-service TKA patients would continue to be treated as inpatients. Nonetheless, many hospitals have decided to schedule all TKA cases as outpatients due to the 2-midnight rule despite a moratorium on recovery audits. It is the position of the American Association of Hip and Knee Surgeons that the CMS needs to provide more specific expectations concerning the needed language justifying admission or exempt TKA from the 2-midnight rule to mitigate the unintended confusion demonstrated by hospitals and some payers that has resulted from the removal of TKA from the Inpatient-Only list.

Socioeconomic Risk Adjustment Models for Reimbursement Are Necessary in Primary Total Joint Arthroplasty.

BACKGROUND: Alternative payment models, such as bundled payments, aim to control rising costs for total knee arthroplasty (TKA) and total hip arthroplasty (THA). Without risk adjustment for patients who may utilize more resources, concerns exist about patient selection and access to care. The purpose of this study was to determine whether lower socioeconomic status (SES) was associated with increased resource utilization following TKA and THA. METHODS: Using the Michigan Arthroplasty Registry Collaborative Quality Initiative database, we reviewed a consecutive series of 4168 primary TKA and THA patients over a 3-year period. We defined lowest SES based upon the median household income of the patient's ZIP code. Demographics, medical comorbidities, length of stay, discharge destination, and readmission rates were compared between patients of lowest SES and higher SES. RESULTS: Patients in the lowest SES group had a longer hospital length of stay (2.79 vs 2.22 days, P < .001), were more likely to be discharged to a rehabilitation facility (27% vs 18%, P < .001), and be readmitted to the hospital within 90 days (11% vs 8%, P = .002) than the higher SES group. Multivariate analysis revealed that lowest SES was an independent risk factor for all 3 outcome variables (all P < .001). CONCLUSION: Patients in the lowest SES group utilize more resources in the 90-day postoperative period. Therefore, risk adjustment models, including SES, may be necessary to fairly compensate hospitals and surgeons and to avoid potential problems with access to joint arthroplasty care.

Decreased length of stay after TKA is not associated with increased readmission rates in a national Medicare sample.

BACKGROUND: There is a trend toward decreasing length of hospital stay (LOS) after TKA although it is unclear whether this trend is detrimental to the overall postoperative course. Such information is important for future decisions related to cost containment. QUESTIONS/PURPOSES: We determined whether decreases in LOS after TKA are associated with increases in readmission rates. PATIENTS AND METHODS: We retrospectively reviewed the rates and reasons for readmission and LOS for 4057 Medicare TKA patients from 2002 to 2007. We abstracted data from the Medicare Patient Safety Monitoring System. Hierarchical generalized linear modeling was used to assess the odds of changing readmission rates and LOS over time, controlling for changes in patient demographic and clinical variables. RESULTS: The overall readmission rate in the 30 days after discharge was 228/4057 (5.6%). The 10 most common reasons for readmission were congestive heart failure (20.4%), chronic ischemic heart disease (13.9%), cardiac dysrhythmias (12.5%), pneumonia (10.8%), osteoarthrosis (9.4%), general symptoms (7.4%), acute myocardial infarction (7.0%), care involving other specified rehabilitation procedure (6.3%), diabetes mellitus (6.3%), and disorders of fluid, electrolyte, and acid-base balance (5.9%); the top 10 causes did not include venous thromboembolism syndromes. We found no difference in the readmission rate between the periods 2002-2004 (5.5%) and 2005-2007 (5.8%) but a reduction in LOS between the periods 2002-2004 (4.1 ± 2.0 days) and 2005-2007 (3.8 ± 1.7 days). CONCLUSIONS: The most common causes for readmission were cardiac-related. A reduction in LOS was not associated with an increase in the readmission rate in this sample. Optimization of cardiac status before discharge and routine primary care physician followup may lead to lower readmission rates.

Age and obesity are risk factors for adverse events after total hip arthroplasty.

BACKGROUND: Defining the epidemiology of adverse events after THA will aid in the development of strategies to enhance perioperative care. QUESTIONS/PURPOSES: We identified (1) risk factors for adverse events in Medicare beneficiaries while hospitalized after THA and (2) trends in the rates of adverse events. PATIENTS AND METHODS: Data were abstracted from medical records of 1809 Medicare beneficiaries who underwent THA from 2002 to 2007. We used the hierarchical generalized linear modeling approach to assess the odds of change in adverse events over time, the association of adverse events with outcomes, and the relationship of adverse events with patient characteristics by modeling the log-odds of adverse events as a function of demographic and clinical variables adjusted for year variable. RESULTS: The overall rate of adverse events was 5.8%; the 30-day mortality rate was 1.00%. Increased age, obesity, and year of procedure were risk factors for experiencing any adverse event. Annual rates of adverse events from 2002 to 2007 were 9.1%, 8.2%, 4.9%, 4.1%, 3.5%, and 3.0%, respectively. Experiencing any adverse event was associated with an increased length of stay and an increased chance of readmission but not with an increased chance of mortality. The annual rate of all adverse events decreased from 2002-2004 to 2005-2007 (odds ratio = 0.83; 95% confidence interval, 0.74-0.92). CONCLUSIONS: Older and obese patients should be counseled regarding their increased risk for the development of adverse events after THA. The cause of the decline in the rate of adverse events between two time periods is unclear and warrants further investigation to confirm and identify the cause.

Readmission and length of stay after total hip arthroplasty in a national Medicare sample.

Evaluation of hospital readmissions after total hip arthroplasty may help improve patient safety and cost reduction. This study investigates the rates and reasons for readmission as well as length of hospital stay (LOS) for 1802 total hip arthroplasty patients from 2002 to 2007. Data were abstracted from the Medicare Patient Safety Monitoring System. The overall 30-day rate of readmission was 6.8%. There was no difference in readmission rate from 2002 to 2004 (7.1%) to 2005 to 2007 (6.3%) (odds ratio, 0.90; 95% confidence interval, 0.63-1.30; P = .58). The overall mean LOS was 4.2 ± 2.2 days. There was a significant reduction in LOS from 2002 to 2004 (4.4 ± 2.5 days) to 2005 to 2007 (3.8 ± 1.7 days) (odds ratio, 1.28; 95% confidence interval, 1.25-1.31; P < .0001). The most common causes for readmission were cardiac related. A reduction in LOS was not associated with an increase in the rate of readmission in this sample. Efforts to optimize cardiac status before discharge may lead to lower rates of readmission in the future.