Disparities in Hip Arthroplasty Outcomes: Results of a Statewide Hospital Registry From 2016 to 2018

BackgroundIn November 2019, Centers for Medicare and Medicaid Services announced total hip arthroplasty (THA) will be removed from the inpatient-only list. This may lead to avoidance of patients who have prolonged hospitalizations and discharge to skilled nursing facilities or push providers to unsafely push patients to outpatient surgery centers. Disparities in hip arthroplasty may worsen as patients are “risk stratified” preoperatively to minimize cost outliers. We aimed to evaluate which patient characteristics are associated with extended length of stay (eLOS)—greater than 2 days—and nonhome discharge in patients undergoing hip arthroplasty.MethodsThe Illinois COMPdata administrative database was queried for THA admissions from January 2016 to June 2018. Variables included age, sex, race and ethnicity, median household income, Illinois region, insurance status, principal diagnosis, Charlson comorbidity index, obesity, discharge disposition, and LOS. Hospital characteristics included bundled payment participation and arthroplasty volume. Using multiple Poisson regression, we examined the association between these factors and the likelihood of nonhome discharge and eLOS.ResultsThere were 41,832 THA admissions from January 2016 to June 2018. A total of 36% had LOS greater than 2 midnights and 25.3% of patients had nonhome discharges. Female patients, non-Hispanic black patients, patients older than 75, obese patients, Medicaid or uninsured status, Charlson comorbidity index > 3, and hip arthroplasty for fracture were associated with increased risk of eLOS and/or nonhome discharge (P < .05).ConclusionWith the Centers for Medicare and Medicaid Services emphasis on cost containment, patients at risk of extended stay or nonhome discharge may be deemed “high risk” and have difficulty accessing arthroplasty care. These are potentially vulnerable groups during the transition to the bundled payment model.     

The Effect of Neuraxial Anesthesia on Postoperative Outcomes in Total Joint Arthroplasty With Rapid Recovery Protocols

BackgroundCompared to general anesthesia (GA), neuraxial anesthesia (NA) has been associated with improved outcomes after total joint arthroplasty (TJA). We examined the impact of NA on patient outcomes in an institution with an established rapid recovery protocol.MethodsThis is a single-institution retrospective analysis of 5914 consecutive primary TJA performed from July 2015 to June 2018. Univariate tests and multivariate regression compared length of stay (LOS), transfusion rates, hematocrit levels, discharge disposition, and emergency room returns between patients receiving GA and NA.ResultsPatients receiving NA had a significantly shorter LOS (total hip arthroplasty [THA]: GA 1.74 vs NA 1.36 days, P < .001; total knee arthroplasty [TKA]: GA 1.77 vs NA 1.64 days, P < .001). Both THA and TKA patients receiving NA were less likely to require transfusion (THA: GA 5.8% vs NA 1.6%, P < .001; TKA: GA 2.5% vs NA 0.5%, P < .001) and had a higher postoperative hematocrit (THA: GA 32.50% vs NA 33.22%, P < .001; TKA GA 33.57 vs NA 34.50%, P < .001). Patients receiving NA were more likely to discharge home (THA: GA 83.4% vs NA 92.3%, P < .001; TKA: GA 83.3% vs NA 86.3%, P = .010) (THA: NA adjusted OR [aOR] 2.04, P < .001; TKA: NA aOR 1.23, P = .048) and had significantly lower rates of 90-day emergency room visits (THA: NA aOR 0.61, P = .005; TKA: NA aOR 0.74, P = .034).ConclusionNA appears to contribute to decreased LOS, short-term complications, and transfusions while facilitating home discharge following TKA and THA. These trends are consistent when controlling for patient-specific risk factors, suggesting NA may enhance outcomes for patients with increased age, body mass index, and comorbidities.Level Of EvidenceLevel III Retrospective Cohort Study.     

The Impact of Frailty on Outcomes Following Primary Total Hip Arthroplasty in Patients of Different Sex and Race: Is Frailty Equitably Detrimental?

BackgroundWhether frailty impacts total hip arthroplasty (THA) patients of different races or sex equally is unknown. This study aimed to assess the influence of frailty on outcomes following primary THA in patients of differing race and sex.MethodsThis is a retrospective cohort study utilizing a national database (2015-2019) to identify frail (≥2 points on the modified frailty index-5) patients undergoing primary THA. One-to-one matching for each frail cohort of interest (race: Black, Hispanic, Asian, versus White (non-Hispanic), respectively; and sex: men versus women) was performed to diminish confounding. The 30-day complications and resource utilizations were then compared between cohorts.ResultsThere was no difference in the occurrence of at least 1 complication (P > .05) among frail patients of differing race. However, frail Black patients had increased odds of postoperative transfusion (odds ratio [OR]: 1.34, 95% confidence interval [CI]: 1.02-1.77), deep vein thrombosis (OR: 2.61, 95% CI: 1.08-6.27), as well as >2-day hospitalization and nonhome discharge (P < .001). Frail women had higher odds of having at least 1 complication (OR: 1.67, 95% CI: 1.47-1.89), nonhome discharge, readmission, and reoperation (P < .05). Contrarily, frail men had higher 30-day cardiac arrest (0.2% versus 0.0%, P = .020) and mortality (0.3 versus 0.1%, P = .002).ConclusionFrailty appears to have an overall equitable influence on the occurrence of at least 1 complication in THA patients of different races, although different rates of some individual, specific complications were identified. For instance, frail Black patients experienced increased deep vein thrombosis and transfusion rates relative to their non-Hispanic White counterparts. Contrarily, frail women, relative to frail men, have lower 30-day mortality despite increased complication rates.     

Which Socioeconomic Factors Affect Outcomes Following Total Hip and Knee Arthroplasty?

BackgroundStudies have shown that lower socioeconomic status may result in adverse outcomes following total hip (THA) and total knee arthroplasty (TKA). The optimal method of defining socioeconomic status, however, continues to be debated. The purpose of this study is to determine which socioeconomic variables are associated with poor outcomes following THA and TKA.MethodsWe reviewed a consecutive series of 2770 primary THA and TKA patients from 2015 to 2018. Utilizing census data based upon the patient’s ZIP code, we extracted poverty, unemployment, high school graduation, and vehicle possession rates. We collected demographics, comorbidities, discharge disposition, 90-day readmissions, and postoperative functional outcome scores for each patient. We then performed a multivariate regression analysis to identify the effect of each socioeconomic variable on postoperative outcomes.ResultsPatients from areas with high unemployment (P = .008) and low high school graduation rates (P = .019) had a higher age-adjusted Charlson Comorbidity Index. High poverty levels, high unemployment, lower high school graduation rate, and lower vehicle possession rates did not have a significant effect on functional outcomes (all P > .05). In the multivariate analysis, no socioeconomic variable demonstrated an increased rate of rehabilitation discharge, revision, or readmission (all P > .05).ConclusionPatients undergoing THA and TKA from areas with high unemployment and lower educational levels do have more medical comorbidities. However, none of the 4 socioeconomic variables studied are independently associated with higher rates of readmission, discharge to rehabilitation, or worse functional outcomes. Patients from disadvantaged areas should not be denied access to arthroplasty care based on socioeconomic status alone.     

Sodium Abnormalities Are an Independent Predictor of Complications in Total Joint Arthroplasty: A Cautionary Tale!

BackgroundElectrolyte levels are commonly obtained as part of the preoperative workup for total joint arthroplasty, but limited information exists on the interplay between electrolyte abnormalities and outcomes.MethodsThe National Surgical Quality Improvement Program was queried for primary, elective total hip arthroplasty and total knee arthroplasty (THA, TKA) performed between 2011 and 2017. Three patient groups were compared: normal (control), hypernatremia, and hyponatremia. The primary outcomes were length of stay (LOS) and 30-day adverse events: complications, readmissions, reoperations, and mortality.ResultsA total of 244,538 TKAs and 145,134 THAs were analyzed. The prevalence of hyponatremia and hypernatremia was 6.9% and 1.0%, respectively. After controlling for any baseline differences, hypernatremia was an independent predictor of ventilation >48 hours (THA, odds ratio [OR] 3.53), unplanned intubation (THA, OR 3.14), cardiac arrest (THA, OR 2.42), pneumonia (THA, OR 2.16), Clostridium difficile infection (OR 4.66 and 3.25 for THA and TKA, respectively), LOS >2 days (THA, OR 1.16), and mortality (THA, OR 4.69). Similarly, hyponatremia was an independent predictor of LOS >2 days (TKA, OR 1.21), readmission (TKA, OR 1.40), reoperation (OR 1.32 and 1.47 for THA and TKA, respectively), surgical site infections (OR 1.39 and 1.54 for THA and TKA, respectively), and transfusion (OR 1.13 and 1.20 for THA and TKA, respectively).ConclusionAs the focus of total joint arthroplasty continues to shift toward value-based payment models and outpatient surgery, caution should be exercised in patients with abnormal preoperative sodium levels, particularly hypernatremia, because of significantly increased risk of prolonged LOS and 30-day adverse events.     

Alcohol Withdrawal Is Associated With Worse Outcomes in Patients Undergoing Primary Total Knee or Total Hip Arthroplasty

BackgroundAlcohol withdrawal (AW) syndrome is an independent risk factor for postoperative complications. This study aims to evaluate the influence of AW on perioperative outcomes in patients who underwent primary total knee (TKA) or total hip arthroplasty (THA).MethodsWe used the National Inpatient Sample database to identify patients undergoing TKA/THA from 2003 to 2014. The primary exposure of interest was AW. Multivariable adjusted models were used to evaluate the association of AW with in-hospital medical complications, surgical complications, mortality, cost, and length of stay (LOS) in patients undergoing TKA/THA.ResultsThere were 2,971,539 adult hospitalizations for THAs and 6,367,713 hospitalizations for TKAs included in the present study, among which 0.14% of AW for THA patients and 0.10% of AW for TKA patients. Multivariable adjustment analysis suggested that AW was associated with an increased risk of medical complications (odds ratio [OR] 2.08, 95% confidence interval [CI] 1.79-2.42, P < .0001), surgical complications (OR 1.75, 95% CI 1.51-2.03, P < .0001), and had 4.79 times increase of in-hospital mortality, 26% increase of total cost, and 53% increase of LOS in THA procedures. For TKA procedures, AW was also associated with increased risk of medical complications (OR 3.14, 95% CI 2.78-3.56, P < .0001), surgical complications (OR 2.07, 95% CI 1.82-2.34, P < .0001) and 4.24 times increase of in-hospital mortality, 29% increase of total cost, and 58% increase of LOS after multivariable adjustment.ConclusionAW is associated with increased risk of in-hospital mortality, medical and surgical complications. Proactive surveillance and management of AW may be important in improving outcomes in patients who underwent THA and TKA procedure.     

Impact of Bariatric Surgery on Inpatient Complication,Cost, and Length of Stay Following Total Hip or Knee Arthroplasty

BackgroundMorbid obesity is an important risk factor for arthroplasty and also closely associated with worse postoperative outcomes. Bariatric surgery is effective in losing weight and decreasing comorbidities associated with obesity. However, no study had demonstrated the influence of bariatric surgery on the outcome of arthroplasty in a large population.MethodsWe used 2006-2014 discharge records from the Nationwide Inpatient Sample, and identified study population and inpatient complications by International Classification of Diseases, 9th Revision, Clinical Modification diagnosis/procedure codes. Propensity score analysis was used to match total hip arthroplasty (THA) or total knee arthroplasty (TKA) patients with morbid obesity and THA or TKA patients with bariatric surgery.ResultsProportion of morbid obesity in both TKA and THA patients demonstrated a rising trend, while proportion of bariatric surgery in morbidly obese TKA and THA patients remains steady after 2007. For THA patients, there was fewer pulmonary embolism, more blood transfusion and anemia, and shorter length of stay in bariatric surgery group. For TKA patients, bariatric surgery group had a lower risk of pulmonary embolism, respiratory complications, death, and shorter length of stay, but bariatric surgery group had a higher risk of blood transfusion and anemia.ConclusionThere is evidence that bariatric surgery prior to arthroplasty, especially THA, appears to reduce rates of pulmonary complications and length of stay. But anemia and blood transfusion seem to be more common in patients with prior bariatric surgery.     

Reasons for Unsuccessful Same-Day Discharge Following Outpatient Hip and Knee Arthroplasty: 5½ Years' Experience From a Single Institution

BackgroundOutpatient joint arthroplasty (OJA) is considered safe and feasible in selected patients but should be further optimized to improve success rates. The purposes of this study are to (1) identify the main reasons of unsuccessful same-day discharge (SDD) following hip and knee arthroplasty; (2) determine the hospital length of stay (LOS) following unsuccessful SDD; and (3) assess which independent variables are related to specific reasons for unsuccessful SDD.MethodsFive hundred twenty-five patients undergoing total hip arthroplasty (THA), total knee arthroplasty (TKA), and unicompartmental knee arthroplasty between 2013 and 2019 were retrospectively identified. SDD to home was planned in all patients. Specific reasons for unsuccessful SDD and LOS were assessed. Bivariate analysis was performed to find differences in independent variables between patients experiencing a specific reason for unsuccessful SDD and control patients.ResultsOne hundred ten patients (21%) underwent unsuccessful SDD. The main reason was postoperative reduced motor function and sensory disturbances (33%). The mean LOS in the unsuccessful SDD group was 1.7 days (standard deviation ± 1.0 days). Postoperative transient reduced motor function and sensory disturbances occurred more often in patients undergoing TKA (P < .001).ConclusionAn option for overnight stay should be available when performing outpatient hip and knee arthroplasty. The main reason for unsuccessful SDD in this study was transient postoperative reduced motor function and sensory disturbance, most likely due to intraoperative local infiltration analgesia in TKA. No other studies have found local infiltration analgesia to be an issue preventing SDD.     

Length of Stay After Joint Arthroplasty is Less Than Predicted Using Two Risk Calculators

BackgroundPredicting the length of stay (LOS) after total joint arthroplasty (TJA) has become more important with their recent removal from inpatient-only designation. The American College of Surgeons (ACS) National Surgical Quality Improvement Program surgical risk calculator and the CMS’ diagnosis-related group (DRG) calculator are two common LOS predictors. The aim of our study was to determine how our actual LOS compared with those predicted by both the ACS and DRG.Methods99 consecutive TJA (49 hips and 50 knee procedures) were reviewed in Medicare-eligible patients from four fellowship-trained arthroplasty surgeons. Predicted LOS was calculated using the DRG and ACS risk calculators for each patient using demographics, medical histories, and comorbidities. LOS was compared between the predicted and the actual LOS for both total hip arthroplasty (THA) and total knee arthroplasty (TKA) using paired t-tests.ResultsActual LOS was shorter in the THA group vs the TKA group (1.29 days vs 1.46 days, P < .05). The actual LOS of patients at our institution was significantly shorter than both DRG and ACS predictions for both THA and TKA (P < .05). In both the THA and TKA patients, the actual LOS (1.29 and 1.46 day) was significantly shorter than the DRG-predicted LOS (2.15 and 2.15 days) which was significantly shorter than the ACS-predicted LOS (2.9 and 3.14 days).ConclusionWe found the actual LOS was significantly shorter than that predicted by both the DRG and ACS risk calculators. Current risk calculators may not be accurate for contemporary fast-track protocols and newer tools should be developed.     

Neighborhood Socioeconomic Disadvantage Associated With Increased Healthcare Utilization After Total Hip Arthroplasty

BackgroundThe multifaceted effects of socioeconomic status on healthcare outcomes can be difficult to quantify. The Area Deprivation Index (ADI) quantifies a socioeconomic disadvantage with higher scores indicating more disadvantaged groups. The present study aimed to describe the ADI distribution for primary total hip arthroplasty (THA) patients stratified by patient demographics and to characterize the association of ADI with healthcare utilization (discharge disposition and length of stay [LOS]), 90-day emergency department (ED) visits, and 90-day all cause readmissions.MethodsTwo thousand three hundred and ninety one patients who underwent primary elective THA over a 13-month period were included. A multivariable binary logistic regression analysis with outcomes of nonhome discharge, prolonged LOS (>3 days), 90-day ED visits, and 90-day readmission were performed using predictors of ADI, gender, race, smoking status, body mass index, insurance status, and Charlson comorbidity index. Plots of restricted cubic splines were used to graph associations between ADI as a continuous variable and the outcomes of interest using odds ratios.ResultsIn the multivariable regression model, there were statistically significant higher odds of nonhome discharge (OR, 1.82; 95% CI, 1.19-2.77, P = .005) for individuals in the 61-80 ADI quintile as compared to the reference group of 21-40. Individuals in the highest ADI quintile, 81-100, had the greatest odds of nonhome discharge (OR, 2.20; 95% CI, 1.39-3.49, P < .001) and prolonged LOS (OR, 1.91, 95% CI, 1.28-2.84, P = .001).ConclusionsHigher ADI is associated with an increased healthcare utilization within 90 days of THA.     

In a Bundled Payment Model,the Costs Associated With Total Joint Replacement in Those Aged Older Than 80 Years Are Significantly Greater

BackgroundThe number of octogenarians requiring a total hip arthroplasty (THA) and/or total knee arthroplasty (TKA) will rise disproportionally in the coming decade. Although outcomes are comparable with younger patients, management of these older patients involves higher medical complexity at a greater expense to the hospital system. The purpose of this study was to compare the cost of care for primary THA and TKA in our bundled care patients aged ≥80 years to those aged 65-80 years.MethodsA retrospective review of primary TKA (n = 641) and THA (n = 1225) cases from 2013 to 2017 was performed. Patient demographic and admission cost data were collected. Patients were grouped based on surgery type (ie, elective or nonelective THA/TKA) and age group (ie, older [≥80 years old] or younger [65-80 years old]). Multivariate regression analyses were used to account for demographic differences.ResultsElective primary THA in the older cohort (n = 157) cost 24.5% more than the younger cohort (n = 1025) (P < .0001). Elective primary TKA cases in the older cohort (n = 87) cost 17.0% more than the younger cohort’s (n = 554) (P < .0001). For nonelective THA cases, the older cohort’s (n = 29) episodes cost 39.1% more than the younger cohort (n = 14) (P < .0001). When comparing the <80 elective THA cohort (n = 1025) to the ≥90 cohort (n = 10), the cost difference swelled to 58.7% (P < .0001).ConclusionAlthough primary THA and TKA in ≥80-year-old patients yield similar outcomes, this study demonstrates that the additional measures required to care for older patients and ensure successful outcomes cost significantly more. Consideration should be given to age as a factor in determining reimbursement in a bundled payment system to reduce the incentive to restrict care to elderly patients.     

Modifiable Analgesia-/Anesthesia-Related Factors and Risk of Severe Gastrointestinal Complications After Lower Extremity Total Joint Arthroplasty: A Nationwide Analysis

BackgroundSevere gastrointestinal (GI) complications after elective hip and knee arthroplasty (THA/TKA) are rare. Some of them can be life-threatening and/or require emergency abdominal surgery. We studied the epidemiology of severe GI complications after THA/TKA and associations with anesthesia- and/or analgesia-related factors.MethodsWe included 591,865 THA and 1,139,616 TKA cases (Premier Healthcare claims database; 2006-2016). Main outcomes were GI complications and related emergency surgeries within 30 days after THA/TKA. Anesthesia- and analgesia-related factors were anesthesia type (neuraxial, general), use of peripheral nerve block, patient-controlled analgesia, nonopioid analgesics (acetaminophen, gabapentin/pregabalin, nonsteroidal anti-inflammatory drugs, cyclooxygenase-2 inhibitors, ketamine), and opioids (in oral morphine equivalents, categorized into low, medium, and high use based on the interquartile range). Mixed-effects models measured associations between anesthesia- and analgesia-related factors and outcomes, which were reported using odds ratios (ORs) and 95% confidence intervals (CIs).ResultsAmong THA patients, GI complications were observed in 1.03% (n = 6103), with 0.08% (n = 450) requiring emergency surgery; this was 0.79% (n = 8971) and 0.05% (n = 540), respectively, for TKA patients. After adjustment for relevant covariates (including opioid use), almost all anesthesia-/analgesia-related factors were associated with significantly decreased odds of GI complications, specifically use of cyclooxygenase-2 inhibitors (OR 0.72 CI 0.67-0.76/OR 0.82 CI 0.78-0.86), nonsteroidal anti-inflammatory drugs (OR 0.81 CI 0.77-0.85/OR 0.90 CI 0.86-0.94), and peripheral nerve blocks (OR 0.77 CI 0.69-0.87/OR 0.91 CI 0.85-0.97); all for THA and TKA, respectively (all P < .01).ConclusionRare, but devastating, acute GI complications (requiring surgery) after THA/TKA may be positively impacted by a variety of modifiable anesthesia-/analgesia-related interventions.     

Can Prior Episode-of-Care Costs Predict the Future? Identifying High-Cost Outliers for Subsequent Total Hip and Knee Arthroplasty

BackgroundIt remains unknown if a patient’s prior episode-of-care (EOC) costs for total hip (THA) or knee (TKA) arthroplasty procedure can be used to predict subsequent costs for future procedures. The purpose of this study is to evaluate whether there is a correlation between the EOC costs for a patient’s index and subsequent THA or TKA.MethodsWe reviewed a consecutive series of 11,599 THA and TKA Medicare patients from 2015 to 2019 and identified all patients who underwent a subsequent THA and TKA during the study period. We collected demographics, comorbidities, short-term outcomes, and 90-day EOC claims costs. A multivariate analysis was performed to identify whether prior high-EOC costs were predictive of high costs for the subsequent procedure.ResultsOf the 774 patients (6.7%) who underwent a subsequent THA or TKA, there was no difference in readmissions (4% vs 5%, P = .70), rate of discharge to a skilled nursing facility (SNF) (15% vs 15%, P = .89), and mean costs ($18,534 vs $18,532, P = .99) between EOCs. High-cost patients for the initial TKA or THA were more likely to be high cost for subsequent procedure (odds ratio 14.33, P < .01). Repeat high-cost patients were more likely to discharge to an SNF for their first and second EOC compared to normative-cost patients (P < .01).ConclusionHigh-cost patients for their initial THA or TKA are likely to be high cost for a subsequent procedure, secondary to a high rate of SNF utilization. Efforts to reduce costs in repeat high-cost patients should focus on addressing post-operative needs pre-operatively to facilitate safe discharge home.     

Factors Associated With Increasing Length of Stay for Rheumatoid Arthritis Patients Undergoing Total Hip Arthroplasty and Total Knee Arthroplasty

Background: Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are cost-effective procedures that decrease pain and improve health-related quality of life for patients with advanced symptomatic arthritis, including rheumatoid arthritis (RA). Patients with RA have a longer length of stay (LOS) after THA or TKA than patients with osteoarthritis, yet the factors contributing to LOS have not been investigated. Purpose: We sought to identify the factors contributing to LOS for patients with RA undergoing THA and TKA at a single tertiary care orthopedic specialty hospital. Methods: We retrospectively reviewed data from a prospectively collected cohort of 252 RA patients undergoing either THA or TKA. Demographics, RA characteristics, medications, serologies, and disease activity were collected preoperatively. Linear regression was performed to explore the relationship between LOS (log-transformed) and possible predictors. A multivariate model was constructed through backward selection using significant predictors from a univariate analysis. Results: Of the 252 patients with RA, 83% were women; they had a median disease duration of 14 years and moderate disease activity at the time of arthroplasty. We had LOS data on 240 (95%) of the cases. The mean LOS was 3.4 ± 1.5 days. The multivariate analysis revealed a longer LOS for RA patients who underwent TKA versus THA, were women versus men, required a blood transfusion, and took preoperative opioids. Conclusion: Our retrospective study found that increased postoperative LOS in RA patients undergoing THA or TKA was associated with factors both non-modifiable (type of surgery, sex) and modifiable (postoperative blood transfusion, preoperative opioid use). These findings suggest that preoperative optimization of the patient with RA might focus on improving anemia and reducing opioid use in efforts to shorten LOS. More rigorous study is warranted.     

Surgeon Reimbursement Unchanged as Hospital Charges and Reimbursements Increase for Total Joint Arthroplasty

BackgroundDespite increasing demands on physicians and hospitals to increase value and reduce unnecessary costs, reimbursement for healthcare services has been under downward pressure for several years. This study aimed to analyze the trend in hospital charges and payments relative to corresponding surgeon charges and payments in a Medicare population for total hip (THA) and knee arthroplasty (TKA).MethodsThe 5% Medicare sample database was used to capture hospital and surgeon charges and payments related to 56,228 patients who underwent primary THA and 117,698 patients who underwent primary TKA between 2005 and 2014. Two values were calculated: (1) the charge multiplier (CM), the ratio of hospital to surgeon charges and (2) the payment multiplier (PM), the ratio of hospital to surgeon payments. Year-to-year variation and regional trends in patient demographics, Charlson Comorbidity Index, length of stay (LOS), CM, and PM were evaluated.ResultsHospital charges were significantly higher than surgeon charges and increased substantially for both THA (CM increased from 8.7 to 11.5, P < .0001) and TKA (CM increased from 7.9 to 11.4, P < .0001). PM followed a similar trend, increasing for both THA and TKA (P < .0001). LOS decreased significantly for both THA and TKA (P < .0001), while Charlson Comorbidity Index remained stable. Both CM (r² = 0.84 THA, 0.90 TKA) and PM (r² = 0.75 THA, 0.84 TKA) were strongly negatively associated with LOS.ConclusionHospital charges and payments relative to surgeon charges and payments have increased substantially for THA and TKA despite stable patient complexity and decreasing LOS.     

The Impact of Frailty Is Age Dependent in Patients Undergoing Primary Total Knee Arthroplasty: The Age-Adjusted Modified Frailty Index

BackgroundFrailty is a well-established risk factor in patients undergoing total knee arthroplasty (TKA). How age modifies the impact of frailty on outcomes in these patients, however, remains unknown. In this study, we aimed to describe and evaluate the applicability of a novel risk stratification tool—the age-adjusted modified Frailty Index (aamFI)—in patients undergoing TKA.MethodsA national database was queried for all patients undergoing primary TKA from 2015 to 2019. There were 271,271 patients who met inclusion criteria for this study. First, outcomes were compared between chronologically young and old frail patients. In accordance with previous studies, the 75th percentile of age of all included patients (73 years) was used as a binary cutoff. Then, frailty was classified using the novel aamFI, which constitutes the 5-item mFI with the addition of 1 point for patients ≥73 years. Multivariable logistic regressions were then used to investigate the relationship between aamFI and postoperative outcomes.ResultsFrail patients ≥73 years had a higher incidence of complications compared to frail patients <73 years. There was a strong association between aamFI and complications. An aamFI of ≥3 (reference aamFI of 0) was associated with an increased odds of 30-day mortality (odds ratio [OR] 8.6, 95% CI 5.0-14.8), any complication (OR 3.1, 95% CI 2.9-3.3), deep vein thrombosis (OR 1.5, 95% CI 1.2-1.8), and nonhome discharge (OR 6.1, 95% CI 5.8-6.4; all P < .001).ConclusionAlthough frailty negatively influences outcomes following TKA in patients of all ages, chronologically old, frail patients are particularly vulnerable. The aamFI accounts for this and represents a simple, but powerful tool for stratifying risk in patients undergoing primary TKA.     

High Bundled Payment Costs Following Total Hip and Knee Arthroplasty in African Americans

BackgroundConcerns exist that minorities who utilize more resources in an episode-of-care following total hip (THA) and knee arthroplasty (TKA) may face difficulties with access to quality arthroplasty care in bundled payment programs. The purpose of this study is to determine if African American patients undergoing TKA or THA have higher episode-of-care costs compared to Caucasian patients.MethodsWe queried Medicare claims data for a consecutive series of 7310 primary TKA and THA patients at our institution from 2015 to 2018. We compared patient demographics, comorbidities, readmissions, and 90-day episode-of-care costs between African American and Caucasian patients. A multivariate regression analysis was performed to identify the independent effect of race on episode-of-care costs.ResultsCompared to Caucasians, African Americans were younger, but had higher rates of pulmonary disease and diabetes. African American patients had increased rates of discharge to a rehabilitation facility (20% vs 13%, P < .001), with higher subacute rehabilitation ($1909 vs $1284, P < .001), home health ($819 vs $698, P = .022), post-acute care ($5656 vs $4961, P = .008), and overall 90-day episode-of-care costs ($19,457 vs $18,694, P = .001). When controlling for confounding comorbidities, African American race was associated with higher episode-of-care costs of $440 (P < .001).ConclusionAfrican American patients have increased episode-of-care costs following THA and TKA when compared to Caucasian patients, mainly due to increased rates of home health and rehabilitation utilization. Further study is needed to identify social variables that can help reduce post-acute care resources and prevent reduction in access to arthroplasty care in bundled payment models.     

Hospital Revenue,Cost, and Contribution Margin in Inpatient Versus Outpatient Primary Total Joint Arthroplasty

BackgroundRemoval of primary total knee arthroplasty (TKA) and primary total hip arthroplasty (THA) from the inpatient-only list has financial implications for both patients and institutions. The aim of this study was to evaluate and compare financial parameters between patients designated for inpatient versus outpatient total joint arthroplasty.MethodsWe reviewed all patients who underwent TKA or THA after these procedures were removed from the inpatient-only list. Patients were statistical significance into cohorts based on inpatient or outpatient status, procedure type, and insurance type. This included 5,284 patients, of which 4,279 were designated inpatient while 1,005 were designated outpatient. Patient demographic, perioperative, and financial data including per patient revenues, total and direct costs, and contribution margins (CMs) were collected. Data were compared using t-tests and Chi-squared tests.ResultsAmong Medicare patients receiving THA, CM was 89.1% lower for the inpatient cohort when compared to outpatient (P < .001), although there was no statistical significance difference between cohorts for TKA (P = .501). Among patients covered by Medicaid or Government-managed plans, CM was 120.8% higher for inpatients receiving THA (P < .001) when compared to outpatients and 136.3% higher for inpatients receiving TKA (P < .001).ConclusionOur analyses showed that recent costs associated with inpatient stay inconsistently match or outpace additional revenue, causing CM to vary drastically depending on insurance and procedure type. For Medicare patients receiving THA, inpatient surgery is financially disincentivized leaving this vulnerable patient population at a risk of losing access to care.Level III EvidenceRetrospective Cohort Study.     

Early Discharge After Total Hip and Knee Arthroplasty—An Observational Cohort Study Evaluating Safety in 330,000 Patients

BackgroundThere has been considerable interest in recent years for early discharge after arthroplasty. We endeavored to evaluate the safety of same-day discharge given the rapid uptake of this practice approach.MethodsThis is a retrospective observational cohort study of the American College of Surgeons National Surgical Quality Improvement Program registry database. We included patients who underwent total hip arthroplasty (THA) or total knee arthroplasty (TKA) between 2015 and 2018. We categorized length of stay (LOS) as same-day discharge (LOS = 0 days), accelerated discharge (LOS = 1 day), and routine discharge (LOS = 2-3 days). For each LOS cohort, we determined the incidence of major complications within 30 days (surgical site infection [SSI], reoperation, readmission, deep vein thrombosis [DVT], and PE) and evaluated risk using multivariate logistic regression analysis if incidence was >1%. Patients undergoing THA and TKA were evaluated independently.ResultsThe final study cohort consisted of 333,212 patients, including 124,150 who underwent THA (37%) and 209,062 who had TKA (63%). In the THA same-day discharge cohort, the incidence of superficial SSI (0.2%), deep/organ space SSI (0.3%), DVT (0.2%), and PE (0.2%) was low. The risk of reoperation was comparable to routine discharge (odds ratio [OR], 0.82; 95% confidence interval [CI], 0.61-1.09; P = .17) and readmission rate was significantly lower (OR, 0.60; 95% CI, 0.48-0.76; P < .001). The risk of reoperation and readmission was also lower in the accelerated discharge cohort compared to routine discharge. In the TKA same-day discharge cohort, the risk of superficial SSI (0.3%), deep/organ space SSI (0.3%), reoperation (0.8%), DVT (0.4%), and PE (0.5%) was low. The risk of readmission after same-day discharge was comparable to routine discharge (OR, 0.85; 95% CI, 0.71-1.01; P = .07). In the accelerated discharge cohort, there was a small reduction in readmission risk (OR, 0.87; 95% CI, 0.81-0.93; P < .001).ConclusionThis large, observational, real-world study suggests that same-day and accelerated discharge management is safe clinical practice for patients undergoing total joint arthroplasty, yielding a similar risk of major acute 30-day complications. Further clinical trials evaluating long-term major outcomes, including patient-reported outcomes and experiences, would offer further and definitive insight into this practice approach.     

Should the Pareto Principle Be Applied as a Cost Savings Method in Hip and Knee Arthroplasty?

BackgroundUnderstanding the most significant contributions to the cost of completing total hip arthroplasty (THA) and total knee arthroplasty (TKA) is essential to optimize costs and meet funding standards. The objectives of this study are to determine whether cost distribution of THA and TKA follows the Pareto Principle (80/20 rule) and factors predictive of costs that could be modified.MethodsAll inpatient, primary, elective, and unilateral THA and TKA patients from April 2008 to September 2017 were retrospectively reviewed. The Pareto Principle was tested by dividing patients into top 5% cost increments and calculating patient cost category ratio. Relationship between patient-related factors and acute care costs and relationship between cost categories and length of stay (LOS) were examined using multiple regression.ResultsThe Pareto Principle does not apply for THA or TKA patients, with the top 20% of costly patients accounting for approximately 30% of total costs. LOS is the strongest independent driver of costs. Operating room services and supplies accounted for over 50% of total costs but with low variability (coefficient of variation < 0.25). Laboratory and allied health costs had high variability (coefficient of variation > 1.5), but their contribution to total costs was low (from 0.76% to 5.68%).ConclusionTHA and TKA costs do not follow Pareto Principle, concluding that targeting top costly patients is not as effective as focusing on overall patient population. Efforts to decrease overall costs should focus on decreasing the LOS and improving operating room process efficiencies including human resources for supplies and instruments.