Introduction. The proportion of arthroplasties performed in the ambulatory setting has increased substantially. However, concerns remain regarding whether same-day discharge may increase the risk of complications. The purpose of this study was to compare 90-day outcomes between inpatients and patients having surgery at an ambulatory surgery center (ASC). Methods. Among a single-surgeon cohort of 721 patients who underwent arthroplasty at a free-standing ASC, 611 (84.7%) were matched one-to-one to inpatients based on age, gender, American Society of Anesthesiologists (ASA) score, and Body Mass Index (110 patients could not be adequately matched). The cohort included 208 total hip arthroplasties (34.0%), 196 total knee arthroplasties (32.1%), 178 unicompartmental knee arthroplasties (29.1%), 25 hip resurfacings (4.1%), two revision hip arthroplasties (0.3%) and two revision knee arthroplasties (0.3%). Post-operative outcomes including readmissions, reoperations, unplanned clinic visits, emergency department visits, and complications were compared. Complications were classified as either major (i.e. death, periprosthetic joint infection, pulmonary embolism) or as minor (i.e. delayed wound healing, rashes, urinary retention). Results. The inpatient and outpatient groups were similar in all demographic variables, reflecting successful matching. The rates of any complications (4.1% outpatient vs. 5.1% inpatient, p=0.41), minor complications (2.6% vs. 3.4%; p=0.40), readmissions (1.6% vs. 2.0%; p= 0.67), reoperations (0.7% vs. 1.1%; p=0.36), and unplanned clinic visits (5.4% vs 6.7%; p=0.34) were all lower amongst the outpatient group but did not reach significance with the sample size studied. The rate of major complications was the same in both groups (1.6% for both; p=1.0) while patients who underwent surgery at an ASC had significantly fewer emergency department visits (1.0% vs. 3.1%; p=0.009). Conclusions. Arthroplasty performed in the ambulatory setting appears to be safe in properly selected patients. However, this finding may be partly due to selection bias and intangible characteristics that were not adequately controlled for through matching

Introduction. In November 2017, the Center for Medicare and Medicaid Services (CMS) finalized the 2018 Medicare Outpatient Prospective Payment System rule that removed total knee arthroplasty (TKA) procedures from the Medicare inpatient-only (IPO) list of procedures. This action had significant and unexpected consequences. For several years, CMS has utilized a rule called the “Two-Midnight Rule” to define outpatient status for all procedures not on the IPO list. CMS made TKA subject to the “Two-Midnight Rule” in conjunction with the decision to move TKA off the IPO list. According to the “Two-Midnight Rule,” a hospital admission should be expected to span at least two midnights in order to be covered as an inpatient procedure. If it can be reliably expected that the patient will not require at least two midnights in the hospital, the “Two-Midnight Rule” suggests that the patient is considered an outpatient and is therefore subject to outpatient payment policies. Under prior guidance related to the “Two-Midnight Rule;” however, CMS also states that Medicare may treat some admissions spanning less than two midnights as inpatient procedures if the patient record contains documentation of medical need. The final rule was clear in stating CMS's expectation was that the great majority of TKAs would continue to be provided in an inpatient setting. Methods. We looked at 3 different levels of the IPO rule impact on TKA for Medicare beneficiaries: a national comparison of fee for service (FFS) inpatient and outpatient classification for 2017 vs 2018; a survey of AAHKS surgeons completed in April of 2019; and an in-depth analysis of a large academic medical center experience. An analysis of change in inpatient classification of TKA patients over time, number of Quality Improvement Organization (QIO) audits, compliance solutions of organizations for the new rule and cost implications of those compliance solutions were evaluated. Results. Hospital reimbursement averages $10,122 in an outpatient facility (includes implant, other supplies, ancillary staff, etc.) but does NOT include the physician payment. Average hospital reimbursement in the inpatient setting is $11,760. The difference in reimbursement to hospitals varies widely however due to nuances in the CMS reimbursement formula (90. th. percentile decrease, $6,725 vs 10th percentile $2,048). Physician payments are the same in both settings (avg $1,403). TKA patients not designated for in-patient admissions are not eligible for bundle payment programs thus removing the healthiest, most predictable patients from the program. Patients designated as outpatients are subject 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. A survey of AAHKS surgeons demonstrated that 44.74% were doing inpatient designation only, 17.89% were doing outpatient designation only, 25.53 % designated patients as necessary, and 10% were designated by the hospital. This survey showed that 66/374 (17.65%) of AAHKS responders had undergone a QIO audit as a result of issues with the IPO rule. An evaluation of a large academic medical center demonstrated that since January 1, 2018, 470/690 (68.1%) of CMS TKA patients left the institution in less than 2 midnights. During this time period the institution was subjected to 2 QIO audits. All CMS patients had been designated as inpatients prior to May 2019. Conclusions. There are many unintended consequences to the IPO rule application to TKA. Clearly, more study is needed to provide better guidelines to knee replacement surgeons. A well-defined outpatient TKA bundle would allow CMS and TKA surgeons to better serve their patients. For figures, tables, or references, please contact authors directly

PURPOSE OF STUDY. We investigated the effect of weekend knee arthroplasty surgery on length of inpatient stay. METHODS. 341 consecutive patients undergoing primary total knee replacement were retrospectively identified. Of these 62 underwent surgery during the weekend. Length of inpatient stay, age, sex, pre-operative haemoglobin, ASA rating, and day of surgery were recorded. Multiple regression analysis was used to determine the effect of these preoperative factors on length of post-operative inpatient stay. RESULTS. The mean length of stay following primary knee replacement was 5.9 days, with a median 4 days (2-31). Multivariate analysis confirmed that age at operation, sex, pre-operative haemoglobin and ASA were predictive of length of stay following knee arthroplasty. The day of the operation was not predictive of length of post operative stay. DISCUSSION. The results from this study suggest age, sex, ASA and preoperative haemoglobin are predictive of inpatient hospital stay. This is consistent with previous published data. Day of surgery was not predictive of length of stay. Our results suggest that weekend knee arthroplasty surgery does not result in an increased length of inpatient stay

Aims . To investigate whether pre-operative functional mobility is a determinant of delayed inpatient recovery of activities (IRoA) after total knee arthroplasty (TKA) in three periods that coincided with changes in the clinical pathway. Patients and Methods. All patients (n = 682, 73% women, mean age 70 years, standard deviation 9) scheduled for TKA between 2009 and 2015 were pre-operatively screened for functional mobility by the Timed-up-and-Go test (TUG) and De Morton mobility index (DEMMI). The cut-off point for delayed IRoA was set on the day that 70% of the patients were recovered, according to the Modified Iowa Levels of Assistance Scale (mILAS) (a 5-item activity scale). In a multivariable logistic regression analysis, we added either the TUG or the DEMMI to a reference model including established determinants. Results. Both the TUG (Odds Ratio (OR) 1.10 per second, 95% confidence intervals (CI) 1.06 to 1.15) and the DEMMI (OR 0.96 per point on the 100-point scale, 95% CI 0.95 to 0.98) were statistically significant determinants of delayed IRoA in a model that also included age, BMI, ASA score and ISAR score. These associations did not depend on the time period during which the TKA took place, as assessed by tests for interaction. . Conclusion. Functional mobility, as assessed pre-operatively by the TUG and DEMMI, is an independent and stable determinant of delayed inpatient recovery of activities after TKA. Future research, focusing on improvement of pre-operative functional mobility through tailored physiotherapy intervention, should indicate whether such intervention enhances post-operative recovery among high-risk patients. Cite this article: Bone Joint J 2017;99-B:211–17

Aims. The purpose of this study was to determine the impact of the removal of total knee arthroplasty (TKA) from the Medicare Inpatient Only (IPO) list on our Bundled Payments for Care Improvement (BPCI) Initiative in 2018. Methods. We examined our institutional database to identify all Medicare patients who underwent primary TKA from 2017 to 2018. Hospital inpatient or outpatient status was cross-referenced with Centers for Medicare & Medicaid Services (CMS) claims data. Demographics, comorbidities, and outcomes were compared between patients classified as ‘outpatient’ and ‘inpatient’ TKA. Episode-of-care BPCI costs were then compared from 2017 to 2018. Results. Of the 2,135 primary TKA patients in 2018, 908 (43%) were classified as an outpatient and were excluded from BPCI. Inpatient classified patients had longer mean length of stay (1.9 (SD 1.4) vs 1.4 (SD 1.7) days, p < 0.001) and higher rates of discharge to rehabilitation (17% vs 3%, p < 0.001). Post-acute care costs increased when comparing the BPCI patients from 2017 to 2018, ($5,037 (SD $7,792) vs $5793 (SD $8,311), p = 0.010). The removal of TKA from the IPO list turned a net savings of $53,805 in 2017 into a loss of $219,747 in 2018 for our BPCI programme. Conclusions. Following the removal of TKA from the IPO list, nearly half of the patients at our institution were inappropriately classified as an outpatient. Our target price was increased and our institution realized a substantial loss in 2018 BPCI despite strong quality metrics. CMS should address its negative implications on bundled payment programmes. Cite this article: Bone Joint J 2020;102-B(6 Supple A):19–23

Aims. The rate of day-case total knee arthroplasty (TKA) in the UK is currently approximately 0.5%. Reducing length of stay allows orthopaedic providers to improve efficiency, increase operative throughput, and tackle the rising demand for joint arthroplasty surgery and the COVID-19-related backlog. Here, we report safe delivery of day-case TKA in an NHS trust via inpatient wards with no additional resources. Methods. Day-case TKAs, defined as patients discharged on the same calendar day as surgery, were retrospectively reviewed with a minimum follow-up of six months. Analysis of hospital and primary care records was performed to determine readmission and reattendance rates. Telephone interviews were conducted to determine patient satisfaction. Results. Since 2016, 301/7350 TKAs (4.1%) in 290 patients at our institution were discharged on the day of surgery. Mean follow-up was 31.4 months (6.2 to 70.0). In all, 28 patients (9.3%) attended the emergency department or other acute care settings within 90 days of surgery, most often with wound concerns or leg swelling; six patients (2.0%) were readmitted. No patients underwent a subsequent revision procedure, and there were no periprosthetic infections. Two patients (0.7%) underwent secondary patella resurfacing, and one patient underwent arthroscopic arthrolysis after previous manipulation under anaesthetic (MUA). Three patients (1.0%) underwent MUA alone. Primary care consultation records, available for 206 patients, showed 16 patients (7.8%) contacted their general practitioner within two weeks postoperatively; two (1.0%) were referred to secondary care. Overall, 115/121 patients (95%) telephoned stated they would have day-case TKA again. Conclusion. Day-case TKA can be safely delivered in the NHS with no additional resources. We found low incidence of contact with primary and secondary care in the postoperative period, and high patient satisfaction. Cite this article: Bone Jt Open 2023;4(8):621–627

Aims. To investigate the impact of consecutive perioperative care transitions on in-hospital recovery of patients who had primary total knee arthroplasty (TKA) over an 11-year period. Methods. This observational cohort study used electronic health record data from all patients undergoing preoperative screening for primary TKA at a Northern Netherlands hospital between 2009 and 2020. In this timeframe, three perioperative care transitions were divided into four periods: Baseline care (Joint Care, n = 171; May 2009 to August 2010), Function-tailored (n = 404; September 2010 to October 2013), Fast-track (n = 721; November 2013 to May 2018), and Prehabilitation (n = 601; June 2018 to December 2020). In-hospital recovery was measured using inpatient recovery of activities (IROA), length of stay (LOS), and discharge to preoperative living situation (PLS). Multivariable regression models were used to analyze the impact of each perioperative care transition on in-hospital recovery. Results. The four periods analyzed involved 1,853 patients (65.9% female (1,221/1,853); mean age 70.1 years (SD 9.0)). IROA improved significantly with each transition: Function-tailored (0.9 days; p < 0.001 (95% confidence interval (CI) -0.32 to -0.15)), Fast-track (0.6 days; p < 0.001 (95% CI -0.25 to -0.16)), and Prehabilitation (0.4 days; p < 0.001 (95% CI -0.18 to -0.10)). LOS decreased significantly in Function-tailored (1.1 days; p = 0.001 (95% CI -0.30 to -0.06)), Fast-track (0.6 days; p < 0.001 (95% CI -0.21 to -0.05)), and Prehabilitation (0.6 days; p < 0.001 (95%CI -0.27 to -0.11)). Discharge to PLS increased in Function-tailored (77%), Fast-track (91.6%), and Prehabilitation (92.6%). Post-hoc analysis indicated a significant increase after the transition to the Fast-track period (p < 0.001 (95% CI 3.19 to 8.00)). Conclusion. This study highlights the positive impact of different perioperative care procedures on in-hospital recovery of patients undergoing primary TKA. Assessing functional recovery, LOS, and discharge towards PLS consistently, provides hospitals with valuable insights into postoperative recovery. This can potentially aid planning and identifying areas for targeted improvements to optimize patient outcomes. Cite this article: Bone Joint J 2024;106-B(6):573–581

Abstract. Introduction. Uni-compartmental knee replacement (UKR) has become popularised due to quicker recovery times, reduced postoperative pain, and blood loss. The desire to increase bed capacity and reduce costs, while preserving safety and patient satisfaction, has led to increased interest in day-case arthroplasty. This study observes the feasibility of UKR as a day-case procedure and whether this affects short and long-term postoperative outcomes. Methodology. Between 2018 and 2021, at a single institution and operated by a single orthopaedic surgeon, seventy-seven patients received a UKR on an elective basis. The patients were divided into two groups: ‘day-case’ for those discharged on the same day, and ‘non day-case’ group. Results. 31 patients were identified as day case procedures with the remaining 46 requiring between one to three days before discharge. Mean age, sex, modal ASA score, BMI, Charlson co-morbidity index, and pre-op oxford knee score showed no statistically significant difference between the two groups (p>0.05). No significant difference between the post-op oxford knee score at 1 year was found for patients treated and discharged as a day case procedure (37.8 +/− 6.88) and those who remained as an inpatient postoperatively (37.8 +/− 10.7); t(df) = −0.0007, p=0.994. No patients in either group suffered any complications beyond the peri-operative period. 30-day and 90-day readmission rates were equal. Conclusions. With no significant differences in post-op knee scores, complication, and readmission rates, we feel UKR can be performed as a viable day case procedure in a planned elective setting. This will result in significant cost savings

Abstract. Introduction. The rate of day-case total knee replacement (TKR) in the UK is currently ~0.5%. Reducing length of stay improves efficiency, increases operative throughput and tackles the rising demand for joint replacement surgery and the COVID-19 related backlog. We report safe delivery of day-case TKR in an NHS Trust via inpatient wards, with no additional resources. Methodology. Day-case TKRs, defined as patients discharged on the same calendar day as surgery, were retrospectively reviewed with a minimum follow-up of six-months. Analysis of hospital and primary care records was performed to determine readmission and reattendance rates. Telephone interviews were conducted to determine patient satisfaction. Results. Between 2016 and 2021, 301/7350 (4.1%) TKRs were discharged on the day of surgery. Mean follow-up was 31.4 (6.2–70.0) months. 28 (9.3%) patients attended Accident and Emergency or other acute care settings within 90-days of surgery; six (2.0%) patients were readmitted. No patients underwent a subsequent revision procedure. There were no prosthetic infections. Two patients underwent secondary patella resurfacing, and one patient underwent arthroscopic arthrolysis after previous manipulation under anaesthetic (MUA). Three patients underwent MUA alone. Primary care consultation records, available for 206 patients, showed 16 (7.8%) patients contacted their General Practitioner within two-weeks post-operatively; two (1.0%) were referred to secondary care. 115/121 (95%) patients telephoned stated they would have day-case TKR again. Conclusion. Day-case TKR can be safely delivered in the NHS with no additional resources. We found low incidence of contact with primary and secondary care in the post-operative period, and high patient satisfaction

Abstract. Introduction. Knee osteotomy, both high tibial and distal femoral osteotomy, is a well-recognised treatment for young, active patients with unicompartmental knee osteoarthritis. Osteotomy around the knee is usually performed as an inpatient procedure. The aim of this study was to assess the effectiveness and patient satisfaction of our day-case protocol for knee osteotomy. Methodology. All patients who underwent day-case knee osteotomy at the study unit, over a three-year period, were reviewed to assess the success of ambulatory care for knee osteotomy. Patients were sent questionnaires to assess functional outcome and patient satisfaction with our day-case process. Results. Thirty-three knee osteotomies were performed as a day-case protocol, of which same day discharge was achieved in 24 patients (73%) and discharge within 24 hours achieved in 32 patients (97%). The mean post-operative Knee Osteoarthritis Outcome Score (KOOS) was 67.1 and 79% of patients rated their care as good or excellent. Return to sporting activities was achieved in 75% of patients, and 88% of patients reported they would be happy to undergo day-case knee osteotomy again. Conclusion. Knee osteotomy, both high tibial and distal femoral osteotomy, can be successfully performed as a day-case procedure with similar improvements in functional outcomes and no increased complication rate, compared to in-patient osteotomy

Abstract. Background. Daycase pathways which aim to discharge patients the same day following Unicompartmental Knee Replacement have been introduced in some centres, though most continue with Standard pathways. While Daycase pathways have cost savings, recovery data comparing pathways is limited. This study aims to compare patient-reported early recovery between Daycase and Standard pathways following UKR. Method. This study was carried out in two centres that originally used the same Standard recovery pathway for UKR. In one centre, the Standard pathway was modified into a Daycase pathway. 26 Daycase-Outpatient, 11 Daycase-Inpatient, and 18 Standard patients were recruited. Patients completed the Oxford Arthroplasty Early Recovery Score (OARS) and SF-36 (Acute) measure between Days 1–42. Results. Standard patients had significantly better Day-1 scores than Daycase patients, but this difference rapidly diminished, and from Day-3 onwards both groups had near-identical scores (OARS Day-1, 59 vs 37, p=0.002, stemming from differences in Pain, Nausea/Feeling-Unwell, Function/Mobility subscores p=0.003,0.014,0.011. OARS Day-3 48 vs 49, p=0.790). Daycase-Outpatients had a higher overall OARS (p=0.002), recovering 1–2 weeks faster than Daycase-Inpatients. OARS subscores demonstrated that Daycase-Outpatients had better Pain, Nausea/Feeling-Unwell, Fatigue/Sleep scores (p=0.020,0.0004,0.019 respectively). SF-36 scores corroborate OARS scores. Conclusion. The Standard cohort had better Day-1 scores than the Daycase cohort, likely due to later mobilisation and stronger inpatient analgesia; these differences diminished by Day-3. Daycase-Outpatients recovered substantially faster than Daycase-Inpatients – likely due to the factors that delayed their discharge. The convergence of scores at 6 weeks demonstrates that both pathways have similar early recovery outcomes

Aims. Robotic arm-assisted surgery offers accurate and reproducible guidance in component positioning and assessment of soft-tissue tensioning during knee arthroplasty, but the feasibility and early outcomes when using this technology for revision surgery remain unknown. The objective of this study was to compare the outcomes of robotic arm-assisted revision of unicompartmental knee arthroplasty (UKA) to total knee arthroplasty (TKA) versus primary robotic arm-assisted TKA at short-term follow-up. Methods. This prospective study included 16 patients undergoing robotic arm-assisted revision of UKA to TKA versus 35 matched patients receiving robotic arm-assisted primary TKA. In all study patients, the following data were recorded: operating time, polyethylene liner size, change in haemoglobin concentration (g/dl), length of inpatient stay, postoperative complications, and hip-knee-ankle (HKA) alignment. All procedures were performed using the principles of functional alignment. At most recent follow-up, range of motion (ROM), Forgotten Joint Score (FJS), and Oxford Knee Score (OKS) were collected. Mean follow-up time was 21 months (6 to 36). Results. There were no differences between the two treatment groups with regard to mean change in haemoglobin concentration (p = 0.477), length of stay (LOS, p = 0.172), mean polyethylene thickness (p = 0.065), or postoperative complication rates (p = 0.295). At the most recent follow-up, the primary robotic arm-assisted TKA group had a statistically significantly improved OKS compared with the revision UKA to TKA group (44.6 (SD 2.7) vs 42.3 (SD 2.5); p = 0.004) but there was no difference in the overall ROM (p = 0.056) or FJS between the two treatment groups (86.1 (SD 9.6) vs 84.1 (4.9); p = 0.439). Conclusion. Robotic arm-assisted revision of UKA to TKA was associated with comparable intraoperative blood loss, early postoperative rehabilitation, functional outcomes, and complications to primary robotic TKA at short-term follow-up. Robotic arm-assisted surgery offers a safe and reproducible technique for revising failed UKA to TKA. Cite this article: Bone Joint J 2024;106-B(7):680–687

Summary. Despite adoption of robust clinical pathways, narcotic administration within the inpatient setting is highly variable and may benefit from the implementation of standardized multi-modal pain management protocols. Introduction. Total knee arthroplasty (TKA) candidates have historically received high doses of opioids within the perioperative period for the management of surgical pain. Healthcare systems have responded by improving opioid prescribing documentation and implementing narcotic-sparing pain protocols into TKA integrated care pathways (ICP). Despite these efforts, there are few technological platforms specifically designed to measure the narcotic burden immediately postoperatively. Here we present an early iteration of an inpatient narcotic administration-reporting tool, which normalizes patient narcotic consumption as an average daily morphine-milligram-equivalence (MME) per surgical encounter (MME/day/encounter) among total knee arthroplasty (TKA) recipients. This information may help orthopaedic surgeons visualize their individual granular inpatient narcotic prescribing habits individually and compared to other surgeons, while taking into consideration patient and procedure specific variables in order to optimize use and curtail unnecessary narcotic prescriptions. Material and Methods. A query of our electronic data warehouse, was performed for patients undergoing elective primary TKA between January 1, 2016 to April 30, 2017. Patients undergoing revision or bilateral procedures were excluded. Patient demographics, inpatient and surgical factors, and inpatient narcotic administration were retrieved. Narcotic type, route and dose were converted into average total Morphine Milligram Equivalents per patient for each post- operative day (figure 1). These MME/day/encounter values were subsequently used determine mean and variance of narcotics prescribed by individual surgeons. A secondary analysis of regional distribution of inpatient narcotic consumption was determined by patient's zip codes. Results. In total, 20 surgeons performed 3,666 primary TKAs. The institutional average narcotic dose administered for a single surgical encounter was 34.45±60.06 MME/day (Figure 1). Average surgeon narcotic prescribing ranged from 18.54 to 42.84 MME/day. Similarly, intra-surgeon variability of narcotic prescribing habits varied from ±20.23 to ±129.02 MME/day. Further visualization of patient breakdown did not demonstrate a trend towards increased narcotic administration or variability for surgeons when compared to race or insurance type. Discussion. Our results suggest that narcotic administration following primary TKA demonstrated a substantial degree of intra-institutional variability for individual surgeons despite the use of standardized clinical pathways. TKA candidates may benefit from the implementation of a more rigid standardization of multi-modal pain management protocols that can control pain while minimizing the narcotic burden. Studies designed to analyze the variability of narcotic use in the post-operative period and determine strategies to minimize inappropriate variation are needed. For any figures or tables, please contact authors directly

Introduction. Previous studies on Medicare populations have shown improved outcomes and decreased 90-day episode-of-care costs with robotic assisted total knee arthroplasty (rTKA). The purpose of this study was to evaluate the expenditures and utilization following rTKA in the under 65 y/o population. Methods. TKA procedures were identified using the OptumInsights Inc. database. A two-year window was studied. The procedures were stratified in two groups: the rTKA or manual (mTKA) cohorts. Propensity score matching (PSM) was performed at 1:5. Utilization and associated costs were analyzed for 90 days following the index procedure. 357 rTKA and 1785 mTKA were included in this analysis. Results. Within the 90 days following the surgery, patients who had robotic assisted procedures were less likely to utilize inpatient services (2.24 vs. 4.37%; p=0.0444) and skilled nursing visits (SNF) (1.68 vs. 6.05%; p<0.0001). No patients in the robotic TKA group went to inpatient rehab while 0.90% of the manual cases went to an inpatient rehabilitation facility. Patients who utilized a home health aide in the rTKA arm utilized significantly fewer days of home health (5.33 vs. 6.36 days; p=0.0037). Cost associated with the utilization of these services was lower in the rTKA arm; the overall post-surgery expenditures were $1,332 less in the rTKA arm ($6,857 vs. $8,189; p=0.0018). The 90-day global expenditures (index plus post-surgery) were $4,049 less in the rTKA arm ($28,204 vs. $32,253; p<0.0001). Lastly, length of stay (LOS) after surgery was nearly a day less for the rTKA arm (1.80 vs. 2.72 days; p<0.0001). Conclusion. Robotic assisted TKA was associated with shorter LOS, reduced utilization of services and reduced 90-day payer costs when compared to the manual TKA. For figures, tables, or references, please contact authors directly

At our tertiary, large, academic healthcare system, we have access to an academic medical center (AMC), a community based, orthopedic friendly, efficient hospital (CBH) and several ambulatory care centers (ASC) which are being prepared to provide same day discharge (SDD) TJA and UKA. We had a near-capacity AMC with an excellent ability to care for medically and technically complicated TJA patients. However, efficiency was less than desired regardless of case complexity with an average effective case time of 4 hours. Concurrently, the orthopaedically, under-utilized community-based hospital (CBH) wanted to increase volume, improve margins, and become a TJA Center of Excellence with the ability to provide an efficient Hospital Outpatient Department (HOPD) and SDD TJA surgery experience. Methods. The CBH had a main operating floor and a separate floor of four OR suites which were repurposed with the goal of utilizing these rooms for TJA four days per week with an average of 3.5 cases per room per day. We preferentially performed primary, uncomplicated TJA, UKA, and minimally invasive TJA at the CBH. Revision surgeries, patients with extensive medical comorbidities, and complex primary surgeries would be performed at the AMC. Our goals were to decrease costs, readmissions, length of stay, and increase margins at the CBH while increasing efficiency, revenue and volume. Protocols were developed to facilitate SDD UKA and THA at both hospitals as well as rapid recovery protocols for TKA at both hospitals with the understanding that the CBH would perform more of these cases but the efficiency could also be implemented at the AMC when possible. We also needed a strategy to deal with TKA and eventually THA being removed from the Inpatient Only (IPO) list. CMS has utilized the “Two-Midnight Rule” to define outpatient status for both THA and TKA. This has distinct financial implications for the facility's reimbursement with outpatient being $10,123 on average versus $12,380 for inpatient status. A protocol-based system was put in place to make both hospitals compliant with the removal of TKA from the IPO List in order to avoid Quality Improvement Organization (QIO) and Recovery Audit Contractor (RAC) after implementation. Results. Comparing FY 2018 to FY 2019, volume increased 26.4% at the CBH. Outpatient case volume rose substantially from 14 cases to 243. Volumes were slightly decreased at the AMC (−4.57%) resulting in a substantial increase in margin contribution for the parent enterprise. Quality metrics at the CBH (surgical site infections (SSI), length of stay (LOS), readmissions, and mortality) were improved. LOS improved from 52% to 71% discharge before 48 hours. The LOS decreased 12% for THA and 8.1% for TKA. CBH readmission rates decreased from 1.38% to 0.9% with no deaths. Surgeon satisfaction is greatly improved as their volume, efficiency, quality metrics, and finances were enhanced. Financial performance was improved in aggregate and per case for the CBH. Although the CBH per-case revenue was 80.3% and 74.4% of the AMC for THA and TKA: the net margins were 3.6% and 18.8% higher for THA and TKA, respectively. The increased efficiency, lower hospital cost and higher volume at the CBH allowed for an increase in revenue despite lower reimbursement per case. Conclusions. A shifting reimbursement landscape, value-based payment initiatives, and increasing volume have challenged traditional TJA delivery systems. This demonstrates one strategy to 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 settings including ambulatory surgery centers which will be subjected to even further decreases in net revenue per patient

Introduction. The Centers for Medicare and Medicaid Services (CMS) removed total knee arthroplasty (TKA) from inpatient-only status in 2018. Our goal was to measure the adoption of outpatient TKAs, the impact on re-treatment rates, and the economic implications for hospitals. Methods. We utilized 100% national Medicare Part A fee-for-service (FFS) patient-level claims data for 2017–2018. We excluded DRG 469 TKAs since they are unlikely to be outpatient candidates, which left 257,107 primary TKAs in 2017 and 264,393 in 2018. We examined the time trend in monthly case volume and 30-day retreatment rate (defined as percent of patients having a second TKA within 30 days of the first. We calculated the loss in revenue for a hospital by multiplying the decrease in payment rate between inpatient and outpatient by the outpatient and total 2018 TKA volume. Results. In 2017 0.2% of primary TKAs were performed outpatient. Following the rule change, 25% of cases were performed outpatient in Q1 2018. This stayed at 25% in Q2, increased to 27% in Q3, and then increased to 30% in Q4 2018. The 30-day re-treatment rate was 0.16% in 2017 and 0.15% in 2018. Across hospitals there was the following distribution in the decrease in payment rate from inpatient to outpatient TKAs in 2018: 10. th. percentile: $1,994, 25. th. : $2,612, 50. th. : $3,487, 75. th. : $4,918, 90. th. : $7,231. In 2018 outpatient TKA coding cost hospitals (saved CMS) $243M in Medicare FFS payments (an average of $89,000 per hospital). If all TKAs were performed outpatient hospital Medicare FFS payments would have been $965M lower ($353,000 per hospital) in 2018. Conclusion. Outpatient TKA volumes grew through 2018. This did not impact 30-day retreatment rates. Medicare FFS payment rates declined by a median of $3,487 per outpatient case. As more TKAs are performed outpatient, total Medicare payments will further decline. For figures, tables, or references, please contact authors directly

Introduction. The success of total knee arthroplasty (TKA) necessitates precise osteotomies and soft tissue balancing to realign the lower extremity to a neutral mechanical axis. While technological advances have facilitated precise osteotomies, soft tissue balancing has traditionally relied mostly on surgeons’ subjective and variable tactile feedback. As soft tissue imbalance accounts for 35% of early TKA revisions in North America, we aimed to compare outcomes when TKA was balanced free-hand versus a sensor-guided balancing device (VERASENSE, OrthoSensor, Inc (Dania, FL)). Methods. In a randomized-controlled fashion, patients underwent primary TKA soft tissue balancing either free-hand or with VERASENSE (Orthosensor Inc, Dania FL) at our institution beginning January 2018. With VERASENSE, soft-tissue balancing is considered when the pressure difference between the medial and lateral knee compartments was less than 15 pounds. Data regarding patient-reported outcomes, knee range of motion (ROM), pain level, opioid consumption, inpatient ambulation distance, length of stay (LOS), and incidence of arthrofibrosis was collected and analyzed in a two-year minimum follow-up and target patient goal of 120 patients. Results. The study cohort thus far consists of 53 patients, average age 72.4 ± 8.8 years. Soft-tissue balance was conducted freehand in 23 patients and the VERASENSE was used in 30 patients. In the free-hand cohort, preoperative patient-reported outcomes for SF-12 Physical, Mental, WOMAC (pain, stiffness, function) parameters, and knee society function score (KSFS) were 39.3, 45.8, 47.7, 37.5, 48.1, and 50.0, respectively and post-operative at 3 months were 45.0, 53.0, 79.5, 72.5, 81.0, and 72.5, respectively; difference between preoperative and post-operative ROM was +8.4 degrees; average VAS pain score in the first 3 post-operative days was 2.9 ± 2.3; average opioid consumption was 100.7 ± 103.3 mg morphine equivalents; average inpatient ambulation per day was 267.9 ± 187.4 feet; average LOS was 2.3 days. In the VERASENSE cohort, patient reported outcomes for SF-12 Physical, Mental, WOMAC (pain, stiffness, function) parameters, and knee society function score (KSFS) were 38.2, 48.6, 40.1, 30.3, 40.0, and 48.7, respectively and post-operative at 3 months were 41.9, 47.6, 67.2, 59.7, 69.1, and 56.7; difference between preoperative and post-operative ROM was +3.9 degrees; average VAS pain score in the first 3 post-operative days was 2.9 ± 2.3; average opioid consumption was 105.8 ± 86.7 mg morphine equivalents; average inpatient ambulation was 384.6 ± 316.1 feet; average LOS was 2.1 days. There was no incidence of arthrofibrosis and subsequent manipulation under anesthesia in the trial. Conclusion. Short-term follow up of this randomized-controlled trial demonstrates equivalent patient-reported and clinical outcomes when soft-tissue balancing in TKA is performed free-hand versus utilization of VERASENSE, though we hypothesize a difference in the long-term

Introduction. Multimodal pain management strategies are now commonplace in perioperative management of total knee arthroplasty (TKA), although controversy remains regarding the role of adductor canal blocks (ACB) in this algorithm. Proposed benefits include theoretical decreased role of perioperative narcotic pain medication, improved function with physical therapy postoperatively, shorter duration of hospital stay and improved patient satisfaction. Those opposed cite increased cost and risk of complications including inadvertent motor blockade. The purpose of this study was to independently evaluate the effect of adductor canal block on short-term post-operative outcomes including (1) length of stay (LOS), (2) post-operative narcotic utilization, and (3) function with physical therapy in the era of modern TKA. Methods. Our institutional database was utilized to retrospectively identify a cohort of consecutive patients from January 2014-January 2018 who had undergone unilateral primary TKA with a single surgeon utilizing a preoperative single-shot ACB in addition to a standardized multimodal pain regimen versus those that only received the same multimodal pain regimen (no-ACB). The primary reason that a patient did not receive a preoperative block was lack of availability of the block team The time period of interest was selected based on the implementation of our current pain protocols. The multimodal pain regimen consists of: preoperative Tylenol, a periarticular injection intraoperatively including 0.5% Marcaine and Toradol, IV Toradol postoperatively, Percocet, Celebrex and IV narcotic medication for breakthrough pain. These 2 groups were compared utilizing independent sample T-tests with primary endpoints of interest being LOS (in total hours and as %day 1 discharges (%POD1)), distance ambulated with inpatient therapy on postoperative day 1, and inpatient narcotic use as measured in morphine equivalents per hour. A sub-cohort of patients with adductor canal block was then selected based on time of surgery to control for time of discharge and hours in the hospital to isolate the effect of the block. Results. There were 624 patients in the ACB group, with a mean age of 64.5 years. The group without ACB consisted of 69 patients, with a mean age of 67.2 years. The no-ACB group was slightly older (p=0.024) but not significantly different in terms of BMI (32.6 vs 31.7, p=0.291). The ACB group ambulated significantly further with inpatient therapy on postoperative day 1 (75.8 vs 59.9 ft, p=0.008), had a shorter LOS in both total hours and %POD1 (34.8 vs 40.6 hours, p=0.01, 83% vs 66.6%, p=0.01). Finally, there was no significant difference between the 2 groups in narcotic utilization postoperatively (2.361 vs 2.0 97, p=0.088). The subcohort of patients that had adductor canal blocks who had their surgery in the afternoon (n=157) were compared to the remainder of the patients to control for LOS data and no statistical differences were seen in either total hospital hours or %POD1. Conclusion. Adductor canal blocks did not decrease post-operative pain medication utilization. The modest improvement in distance ambulated with therapy on POD1 (16 ft) and length of stay (16% greater POD1 discharges) of hospitalization may not support the cost effectiveness of this intervention

The statements contained in this document are solely those of the authors and do not necessarily reflect the views or policies of CMS. The authors assume responsibility for the accuracy and completeness of the information contained in this document. Background. The Bundled Payments for Care Improvement (BPCI) initiative was introduced to reduce healthcare costs while maintaining quality. We examined data from a healthcare system comprised of five hospitals that elected to participate in the BPCI Major Joint Replacement of the Lower Extremity Model 2 initiative beginning July 1, 2015. We compared one hospital that did 507 BPCI knee cases to the four other hospitals that did 566 cases. Stratifying the data by hospital volume, we sought to determine if costs decreased during the BPCI period, how the savings were achieved, and if savings resulted in financial rewards for participation. Methods. The Medicare data included the target cost for each episode (based on historical data from 2009–2012 for each hospital that was adjusted quarterly) and actual Part A and Part B spending for 90 days. Using 1,836 primary knee replacements, we analyzed the costs associated with the anchor hospitalization, inpatient rehabilitation, skilled nursing facilities, home health, outpatient physical therapy and readmission to compare the 1,073 knees done during the 16-month BPCI initiative period with the 763 knees done during the 1-year period preceding BPCI participation. Owing to the nonparametric distribution of the cost data, a Mann-Whitney U test was used to compare the higher volume hospital with the four lower volume hospitals. Results. Compared to the preceding year, the mean episode of care cost during BPCI participation decreased by 8.5% (from $20,853 to $19,087, p=0.24) at the higher volume hospital while remaining virtually unchanged (going from $20,383 to $20,380, p=0.10) at the lower volume hospitals. During the BPCI period, the mean Medicare 90-day target cost was $18,307 at the higher volume hospital and $22,287 at the lower volume hospitals (p<0.001). At the higher volume hospital, the major components of the savings included $367,290 from reduced readmission rates (5.7% versus 8.7%, p=0.11), $207,608 primarily due to a reduction in the length of stay at skilled nursing facilities (mean 15 days versus 25 days, p=0.005), and $130,894 associated with a decreased percentage of patients using inpatient rehabilitation (3.2% versus 4.9%, p=0.22). Although offset by other cost increases, the largest component of the savings at the lower volume hospitals was $262,548 due to a decrease in the percentage of patients (2.3% versus 4.8%, p=0.04) using inpatient rehabilitation. Despite its savings, the mean reconciliation penalty was $851 per case at the higher volume hospital while the lower volume hospitals received a mean reward of $2,165 per case. Conclusion. Based on the reduction in costs and decreased readmission rates, the BPCI initiative is achieving its objectives. Despite an 8.5% decrease in costs, the $18,307 target based on historical data resulted in an $851 penalty per case at the higher volume hospital. In contrast, as a result of a $3,980 higher target, the lower volume hospitals were rewarded even though they did not achieve cost savings. As structured, there is no incentive for centers with historically low costs to participate in BPCI

Background. As the number of total knee arthroplasties (TKA) being performed continues to increase, the number of potential failures requiring revision surgery would also be expected to increase. This study analyzed the trends in revision TKA (rTKA) from 2009 to 2016. Methods. The Nationwide Inpatient Sample (NIS) database was used to identify all rTKA by International Classification of Diseases, Ninth Revision (ICD-9) and Tenth Revision (ICD-10) codes. The diagnoses leading to revision, revision costs, patient and hospital characteristics, and major inpatient complications were compared between 2009 and 2016. Multivariate logistic regression analyses were used to calculate odds ratios (OR) for complications. Results. A total of 453,770 rTKA were performed between 2009 and 2016 (Table 1). The incidence of rTKA between 2009 and 2016 decreased by 4.3% among all age groups and decreased 5.9% in those over 65 years of age. The mean age at revision remained unchanged at 65 years, the mean Length of Stay (LOS) decreased 19.5% from 4.1 to 3.3 days (p<0.001), and the mean hospital costs increased 18.7% from $23,103 to $27,427 (p<0.001). Male to Female ratio remained unchanged with Females making up 58% of rTKA. The rTKA patients in 2016 versus 2009 had significantly lower odds of requiring a blood transfusion (OR 0.26, p<0.001). The rate of myocardial infarction remained unchanged in 2016 versus 2009 (4.1% vs. 4.0%, p=0.52), as did mortality (0.1% vs. 0.2%, p=0.089). Patients in 2016 were significantly less likely to be discharged to a skilled nursing facility (SNF) (26.5% in 2016 vs. 31.6% in 2009, p<0.001). A significantly larger share of rTKA were performed in urban teaching hospitals in 2016 (66.6% in 2016 vs. 41.5% in 2009, p<0.001). Mechanical loosening remained the most common reason for rTKA and increased from 19.7% in 2009 to 28.4% in 2016. Infection remained the second most common reason for rTKA (14.7% in 2009 vs. 12.2% in 2016). Instability was the third most common reason for revision in 2016 (10.7%) but direct comparison with 2009 could not be made since ICD-9 did not include this diagnosis. When comparing 2009 to 2014, an increase in revision rates was noted. Upon inclusion of 2015 and 2016 data, a decrease is noted. The primary limitation of this study is the challenge faced when comparing results from before and after the October 2015 transition of ICD-9 to ICD-10 codes. Conclusions. The incidence of rTKA had decreased slightly between 2009 and 2016 even while the volume of primary TKA continued to rise. Implant loosening became increasingly prevalent as a reason for revision and infection continued to plague patients after TKA. Positive trends were noted, such as decreased rates of blood transfusion, LOS and rates of discharge to SNF. Still, the revision burden remains large, costing approximately $1.4 billion annually and we must continue to attempt to improve outcomes in this patient population. For figures, tables, or references, please contact authors directly