Total Knee Arthroplasty Removal From the Medicare Inpatient-Only List: Implications for Surgeons, Patients, and Hospitals: Introduction

Same-Day Total Joint Arthroplasty in the United States From 2016 to 2020: The Impact of the Medicare Inpatient Only List and the COVID-19 Pandemic

BACKGROUND

Same-day total hip arthroplasty (THA) and total knee arthroplasty (TKA) continue to gain popularity in the United States. The present study sought to quantify recent same-day outpatient trends taking into consideration the COVID-19 pandemic as well as the removal of these procedures from the Medicare inpatient only (IPO) list.

METHODS

Patients undergoing primary elective TKA and THA were identified using the Nationwide Ambulatory Surgery Sample and the National Inpatient Sample from January 1, 2016, to December 31, 2020. The same-day cohort included Nationwide Ambulatory Surgery Sample and National Inpatient Sample patients with a length of stay = 0 days. The inpatient cohort included patients with length of stay ≥1 day. National estimates were extrapolated using weight functions.

RESULTS

From January 2016 to December 2020, the proportion of same-day TKA increased from 1.2 (719) to 62.4% (31,293) and the proportion of same-day THA increased from 2.0 (599) to 54.5% (18,252). Following removal from the Medicare IPO list, same-day TKAs increased from 3.2% (1,895) in December 2017 to 13.8% (9,269) in January 2018, and same-day THAs increased from 10.7% (4,295) in December 2019 to 22.5% (8,708) in January 2020. Between February and March 2020, same-day TKAs increased from 42.4 (26,148) to 44.4% (16,972) and same-day THAs increased from 28.5 (10,729) to 30.2% (7,409).

CONCLUSIONS

The proportion of same-day TKA and THA dramatically increased following removal from the Medicare IPO list and in response to the COVID-19 pandemic. By December 2020, same-day TKA and THA accounted for >50% of all cases performed in the United States.

Outpatient Total Knee Arthroplasty From a Stand-Alone Surgery Center: Safe as the Hospital?

BACKGROUND

Literature suggests that outpatient arthroplasty may result in low rates of complications and readmissions. There is, however, a dearth of information on the relative safety of total knee arthroplasty (TKA) performed at stand-alone ambulatory surgery centers (ASCs) versus hospital outpatient (HOP) settings. We aimed to compare safety profiles and 90-day adverse events of these 2 cohorts.

METHODS

Prospectively collected data were reviewed on all patients who underwent outpatient TKA from 2015 to 2022. The ASC and HOP groups were compared, and differences in demographics, complications, reoperations, revisions, readmissions, and emergency department (ED) visits within 90 days of surgery were analyzed. There were 4 surgeons who performed 4,307 TKAs during the study period, including 740 outpatient cases (ASC = 157; HOP = 583). The ASC patients were younger than HOP patients (ASC = 61 versus HOP = 65; P < .001). Body mass index and sex did not differ significantly between groups.

RESULTS

Within 90 days, 44 (6%) complications occurred. No differences were observed between groups in rates of 90-day complications (ASC = 9 of 157, 5.7% versus HOP = 35 of 583, 6.0%; P = .899), reoperations (ASC = 2 of 157, 1.3% versus HOP = 3 of 583, 0.5%; P = .303), revisions (ASC = 0 of 157 versus HOP = 3 of 583, 0.5%; P = 1), readmissions (ASC = 3 of 157, 1.9% versus HOP = 8 of 583, 1.4%; P = .625), and ED visits (ASC = 1 of 157, 0.6% versus HOP = 3 of 583, 0.5%; P = .853).

CONCLUSION

These results suggest that in appropriately selected patients, outpatient TKA can be safely performed in both ASC and HOP settings with similar low rates of 90-day complications, reoperations, revisions, readmissions, and ED visits.

The removal of total hip arthroplasty from the inpatient-only list has improved patient selection and expanded optimization efforts

INTRODUCTION

On January 1, 2020, the Centers for Medicare and Medicaid Services removed total hip arthroplasty (THA) from the Inpatient-Only (IPO) list. This study evaluated patient demographics and comorbidities, pre-operative optimization efforts, and 30-day outcomes of patients undergoing outpatient THA pre- and post- IPO-removal. The authors hypothesized that patients undergoing THA post-IPO removal would have improved optimization of modifiable risk factors and equivalent 30-day outcomes.

METHODS

There were 17,063 outpatient THA in a national database stratified by surgery performed pre- (2015 to 2019: 5,239 patients) and post-IPO (2020: 11,824 patients) removal. Demographics, comorbidities, and 30-day outcomes were compared with univariable and multivariable analyses. Pre-operative optimization thresholds were established for the following modifiable risk factors: albumin, creatinine, hematocrit, smoking history, and body mass index. The percentage of patients who fell outside the thresholds in each cohort were compared.

RESULTS

Patients undergoing outpatient THA post-IPO removal were significantly older; mean age 65 years (range, 18 to 92) vs 62 (range, 18 to 90) years (P<0.01), with a higher percentage of American Society of Anesthesiologists scores 3 and 4 (P<0.01). There was no difference in 30-day readmissions (P=0.57) or reoperations (P=1.00). A significantly lower percentage of patients fell outside the established threshold for albumin (P<0.01) post-IPO removal, and trended towards lower percentages for hematocrit and smoking status.

CONCLUSION

The removal of THA from the IPO list expanded patient selection for outpatient arthroplasty. Pre-operative optimization is critical to minimize post-operative complications, and the current study demonstrates that 30-day outcomes have not worsened post-IPO removal.

Increased Patient-Level Payment After Removal of Total Knee Arthroplasty From the Inpatient-Only List

BACKGROUND

In January 2018, the Centers for Medicare and Medicaid Services removed total knee arthroplasty (TKA) from the Inpatient Only (IPO) list. This study aimed to compare patient-level payments in TKA cases with a length of stay (LOS) <2 midnights before and after removal of TKA from IPO list.

METHODS

In this retrospective cohort study, all Medicare patients who received a primary elective TKA from 2016-2019 with a LOS <2 midnights at an academic tertiary center were identified. Total and itemized charges and patient-level payments were compared between eligible TKA cases performed in 2016-2017 and those in 2018-2019. There were 351 eligible TKA cases identified: 151 in 2016-2017 and 200 in 2018-2019.

RESULTS

The percentage of patients making any out-of-pocket payment increased in 2018-2019 from 2016-2017 (51.0% versus 10.6%), as did median patient-level payment ($7.30 [range, $0.00-$3,389] versus $0.00 [range, $0.00-$1,248], P < .001 for both). A greater proportion of patients in 2018-2019 paid $1-$50 than in 2016-2017 (37.5% versus 1.3%, P < .001) with no change in the proportion of patients who made payments >$50. Total charges were less in 2018-2019 than in 2016-2017 (P = .001). Charges for drugs, laboratory tests, admissions/floor, and therapies decreased in 2018-2019, whereas charges for the operating room and radiology increased (P < .001 for all).

CONCLUSION

Patients receiving outpatient TKA in 2018-2019 were more likely to have out-of-pocket payments than patients with comparable hospital stay who were designated as inpatients, although most of these payments were less than $50.

Improving Arthroplasty Efficiency and Quality Through Concentrating Service Volume by Complexity: Surviving the Medicare Policy Changes

We have an academic medical center (AMC), an associated community-based hospital (CBH) and several ambulatory care centers which are being prepared to provide same day discharge (SDD) total joint arthroplasty (TJA) and unicompartmental knee arthroplasty (UKA). The near-capacity AMC cared for medically and technically complicated TJA patients. The CBH wanted to increase volume, improve margins, and become a center of excellence with an efficient hospital outpatient department and SDD TJA experience.

METHODS

We transitioned primary, uncomplicated TJA, UKA, and minimally invasive TJA to the CBH. Revision surgeries, patients with extensive comorbidities, and complex primaries were performed at the AMC. Protocols were developed to facilitate SDD UKA and total hip arthroplasty (THA) as well as rapid recovery protocols for total knee arthroplasty (TKA) at both hospitals. A protocol-based system was put in place to make both hospitals ready for the removal of TKA from the Inpatient-Only list to avoid Quality Improvement Organization and possible resultant Recovery Audit Contractor audits if referred after implementation.

RESULTS

The CBH volume increased 36.7% (+239). AMC volume slightly decreased (-0.46%, -5) resulting in an increase in margin contribution for the system. CBH quality metrics (surgical site infections, length of stay, readmissions, and mortality) were improved. Surgeon satisfaction improved as their volume, efficiency, quality metrics, and finances were enhanced. Although CBH per case revenue was 80.3% and 74.4% of the AMC for THA and TKA, net margins were 3.6% and 18.8% higher for THA and TKA, respectively. Increased efficiency, lower hospital cost, and higher volume at the CBH allowed for an increase in revenue despite lower reimbursement per case.

CONCLUSION

This strategy will help hospital systems improve net margins while improving patient care despite lower net revenue per TJA episode. These strategies will become increasingly important going forward with the transition of higher numbers of TJA patients to outpatient which will be subjected to further decreases in net revenue per patient.

Despite Equivalent Medicare Reimbursement, Facility Costs for Outpatient Total Knee Arthroplasty Are Higher Than Unicompartmental Knee Arthroplasty

BACKGROUND

With the recent removal of total knee arthroplasty (TKA) from the Centers for Medicare and Medicaid Services (CMS) Inpatient Only list, facility reimbursement for outpatient TKA now falls under the Outpatient Prospective Payment System at the same rate as unicompartmental knee arthroplasty (UKA). The purpose of this study was to compare true facility costs of patients undergoing outpatient TKA with those undergoing UKA.

METHODS

We reviewed a consecutive series of 2310 outpatient TKA and 231 UKA patients from 2018 to 2019. Outpatient status was defined as a hospital stay of less than 2 midnights. Facility costs were calculated using a time-driven, activity-based costing algorithm. Implants, supplies, medications, and personnel costs were compared between outpatient TKA and UKA patients. A multivariate analysis was performed to control for confounding medical and demographic variables.

RESULTS

When compared with patients undergoing UKA, outpatient TKA patients had higher implant costs ($3403 vs $3081; P < .001) and overall hospital costs ($6350 vs $5594; P < .001). Outpatient TKA patients had a greater length of stay (1.2 vs 0.5 days; P < .001) and greater postoperative personnel costs ($783 vs $166; P < .001) than UKA patients. When controlling for comorbidities, outpatient TKA was associated with a $803 (P < .001) increase in overall facility costs compared with UKA.

CONCLUSION

Despite equivalent reimbursement from CMS as UKA, outpatient TKA has increased facility costs to the hospital. Although implant costs can vary greatly by institution, CMS should consider appropriately reimbursing outpatient TKA for the additional personnel costs when compared with UKA.

Medicare Total Knee Arthroplasty Patients Need Not Stay 2 Midnights for Full Facility Reimbursement

BACKGROUND

Health care systems are concerned that facility reimbursements will be reduced based on patient length of stay (LOS) of <2 midnights with the removal of total knee arthroplasty (TKA) from the inpatient-only list. The purpose of this study was to evaluate the effect of LOS and postdischarge disposition on facility reimbursement.

METHODS

We evaluated a consecutive series of 470 primary Medicare TKA patients performed at a single institution from 2018 to 2019. We analyzed facility reimbursement based on patient LOS and discharge disposition. Descriptive statistics were analyzed using chi-square test, analysis of variance, and Student t test calculations.

RESULTS

Overall, the facility was fully reimbursed in 401 patients (85%) at a mean of $11,169. The facility received full reimbursement for 323 of 326 (99%) patients with an LOS of <2 midnights who were discharged to home at a mean of $11,156. This reimbursement was significantly (P < .001) higher than patients who had an LOS <2 midnights who were discharged with home health (mean, $9773) or to a facility (mean, $10,095). For those with LOS >2 midnights, there was no difference in mean reimbursement among discharge dispositions ($11,202 vs $11,249 vs $11,085, P = .65).

CONCLUSION

In this study, Medicare TKA patients with LOS <2 midnights were fully reimbursed 99% of the time as an inpatient as long as they are discharged to home without home health or to a rehabilitation facility. Those discharged before 2 midnights who require home health service or inpatient facility are more likely to be reimbursed at a lower penalized rate.

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.