Bundled Payments in Total Joint Replacement: Keeping Our Care Affordable and High in Quality

Patients With Moderate to Severe Liver Cirrhosis Have Significantly Higher Short-Term Complication Rates Following Total Knee Arthroplasty: A Retrospective Cohort Study

BACKGROUND

Liver cirrhosis is associated with increased perioperative morbidity. Our study used the Model for End-Stage Liver Disease (MELD) score to assess the impact of cirrhosis severity on postoperative outcomes following total knee arthroplasty (TKA).

METHODS

A retrospective review identified 59 patients with liver cirrhosis who underwent primary TKA at a large, urban, academic center from January 2013 to August 2022. Cirrhosis was categorized as mild (MELD < 10; n = 47) or moderate-severe (MELD ≥ 10; n = 12). Modified Clavien-Dindo classification was used to grade complications, where grade 2+ denoted significant intervention. Hospital length of stay, nonhome discharge, and mortality were collected. A 1:1 propensity matching was used to control for demographics and selected comorbidities.

RESULTS

Moderate-severe cirrhosis was associated with significantly higher rates of intrahospital overall (58.33 versus 16.67%, P = .036) complications, 30-day overall complications (75 versus 33.33%, P = .042), and 90-day overall complications (75 versus 33.33%, P = .042) when compared to matched mild cirrhosis patients. Compared to matched noncirrhotic controls, mild cirrhosis patients had no significant increase in complication rate or other outcomes (P > .05).

CONCLUSIONS

Patients with moderate-severe liver cirrhosis are at risk of short-term complications following primary TKA. Patients with mild cirrhosis have comparable outcomes to matched noncirrhotic patients. Surgeons can use MELD score prior to scheduling TKA to determine which patients require optimization or higher levels of perioperative care.

Projected volume of primary total joint arthroplasty in the USA from 2019 to 2060

INTRODUCTION

The global incidence of total joint arthroplasty (TJA) has consistently risen over time, and while various forecasts differ in magnitude, future projections suggest a continued increase in these procedures. Differences in future United States projections may arise from the modeling method selected, the nature of the national arthroplasty registry employed, or the representativeness of the specific hospital discharge records utilized. In addition, many models have not accounted for ambulatory surgery as well as all payer types. Therefore, to attempt to make a more accurate model, we utilized a national representative sample that included outpatient arthroplasties and all insurance types to predict the volumes of primary TJA in the USA from 2019 to 2060.

METHODS

A national, all-payer database was queried. All patients who underwent primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) from January 1, 2010, to December 31, 2019, were identified using international classification of disease Ninth Revision (9) and Tenth Revision (10) codes and current procedure terminology codes. Absolute frequencies and incidence rates were calculated per 100,000 for both THA and TKA procedures, with 95% confidence intervals. Mean growth in absolute frequency and incidence rates were calculated for each procedure from 2010 to 2014, and 2010 to 2019, with 95% confidence intervals (CI).

RESULTS

The overall increase in THA and TKA procedures are expected to grow + 10 and + 36%, respectively, using linear regressions and + 9 and + 37%, respectively. The most positive mean growth in procedure frequency occurred from 2010 to 2014 for THA (+ 24, 95% Confidence Interval (CI): + 21, + 27) and 2010-2019 for TKA (+ 11%, 95% CI: + 9, + 14). There positive trend patterns in incidence rate growth for both procedures, with similar 2010-2019 incidence rates + 6%) for THA (+ 3%, 95% CI: + 0, + 6%) and TKA (+ 3%, 95% CI: + 1%, + 6%).

CONCLUSION

Utilizing a nationally representative database, we demonstrated that TJA procedures would continue with an increased growth pattern to 2060, though slightly decreased from the surge from 2014 to 2019. While this finding applies to the representativeness of the population at hand, the inclusion of outpatient arthroplasty and all payer types validates an approach that has not been undertaken in previous projection studies.

Identification of Surgeon Outliers to Improve Cost Efficiency: A Novel Use of the Centers for Medicare and Medicaid Quality Payment Program

BACKGROUND

Bundled payment programs for total joint arthroplasty (TJA) have become popular among both private and public payers. Because these programs provide surgeons with financial incentives to decrease costs through reconciliation payments, there is an advantage to identifying and emulating cost-efficient surgeons. The objective of this study was to utilize the Centers for Medicare and Medicaid Services (CMS) Quality Payment Program (QPP) in combination with institutional data to identify cost-efficient surgeons within our region and, subsequently, identify cost-saving practice patterns.

METHODS

Data was obtained from the CMS QPP for total knee arthroplasty (TKA) and total hip arthroplasty (THA) surgeons within a large metropolitan area from January 2019 to December 2021. A simple linear regression determined the relationship between surgical volume and cost-efficiency. Internal practice financial data determined whether patients of identified surgeons differed with respect to x-ray visits, physical therapy visits, out-of-pocket payments to the practice, and whether surgery was done in hospital or surgical center settings.

RESULTS

There were 4 TKA and 3 THA surgeons who were cost-efficiency outliers within our area. Outliers and nonoutlier surgeons had patients who had similar body mass index, American Society of Anesthesiologists Physical Status Score, and age-adjusted Charlson Comorbidity Index scores. Patients of these surgeons had fewer x-ray visits for both TKA and THA (1.06 versus 1.11, P < .001; 0.94 versus 1.15, P < .001) and lower out-of-pocket costs ($86.10 versus $135.46, P < .001; $116.10 versus $177.40, P < .001). If all surgeons performing > 30 CMS cases annually within our practice achieved similar cost-efficiency, the savings to CMS would be $17.2 million for TKA alone ($75,802,705 versus $93,028,477).

CONCLUSIONS

The CMS QPP can be used to identify surgeons who perform cost-efficient surgeries. Practice patterns that result in cost savings can be emulated to decrease the cost curve, resulting in reconciliation payments to surgeons and institutions and cost savings to CMS.

A Cautionary Tale: Malaligned Incentives in Total Hip and Knee Arthroplasty Payment Model Reforms Threaten Promising Innovation and Access to Care

Over the past several years, there have been notable changes and controversies involving Medicare reimbursement for total hip (THA) and total knee arthroplasty (TKA). We have seen the development and implementation of experimental bundled payment model pilot programs goals of improving quality and decreasing overall costs of care during the last decade. Many orthopaedic surgeons have embraced these programs and have demonstrated the ability to succeed in these new models by implementing strategies, such as preservice optimization, to shift care away from inpatient or postdischarge settings and reduce postoperative complications. However, these achievements have been met with continual reductions in surgeon reimbursement rates, lower bundle payment target pricings, modest increases in hospital reimbursement rates, and inappropriate valuations of THA and TKA Common Procedural Terminology (CPT) codes. These challenges have led to an organized advocacy movement and spurred research involving the methods by which improvements have been made throughout the entire episode of arthroplasty care. Collectively, these efforts have recently led to a novel application of CPT codes recognized by payers to potentially capture presurgical optimization work. In this paper, we present an overview of contemporary payment models, summarize notable events involved in the review of THA and TKA CPT codes, review recent changes to THA and TKA reimbursement, and discuss future challenges faced by arthroplasty surgeons that threaten access to high-quality THA and TKA care.

Ten Year Experience With Same Day Discharge Outpatient Total Hip Arthroplasty: Patient Demographics Changed, but Safe Outcomes Were Maintained

BACKGROUND

This study aimed to characterize changes in patient demographics and outcomes for same-day discharge total hip arthroplasty (THA) over a 10-year period at a single orthopaedic specialty hospital.

METHODS

A consecutive series of 1,654 patients between 2013 and 2022 who underwent unilateral THA and were discharged on the same calendar day were retrospectively reviewed. Patient demographics, including age, sex, body mass index (BMI), age-adjusted Charlson Comorbidity Index, and American Society of Anesthesiologists (ASA), were collected. Readmissions, complications, and unplanned visits were recorded for 90 days postoperatively. In order to compare the demographics of patients over time, patients were divided into 3 groups: Time Group A (2013 to 2016), Time Group B (2017 to 2019), and Time Group C (2020 to 2022).

RESULTS

The mean age, BMI, ASA score, and CCI increased significantly across each time group. Age increased from 57 years (range, 23 to 77) to 60 years (range, 20 to 87). The BMI increased from 28.1 (range, 18 to 41) to 29.4 (range, 18 to 47). The percentage of patients aged > 70 years almost doubled over time, as did the percentage of patients who had a BMI > 35. Overall complications increased from 3.44 to 6.82%, reflective of the changing health status of patients. Readmissions increased from 0.57 to 1.70% over time. Despite this, there were no readmissions for any patient within the first 24 hours of surgery.

CONCLUSIONS

Our study has 3 important findings. We identified a worsening patient demographic over time with an increasing percentage of patients of advanced age and higher BMI, ASA, and age-adjusted Charlson Comorbidity Index. Also, there was also an increase in readmissions, complications, and unplanned visits. In addition, despite this worsening patient demographic, there were no readmissions within 24 hours and a low rate of readmissions or unplanned visits within the first 48 hours across all time periods, suggesting that same-day discharge-THA continues to be safe in properly selected patients.

Patient-reported outcome differences for navigated and robot-assisted total hip arthroplasty frequently do not achieve clinically important differences: a systematic review

INTRODUCTION

Total hip arthroplasty (THA) using computer-assisted navigation (N-THA) and robot-assisted surgery (RA-THA) has been increasingly adopted to improve implant positioning and offset/leg-length restoration. Whether clinically meaningful differences in patient-reported outcomes (PROMs) compared to conventional THA (C-THA) are achieved with intraoperative technology has not been established. This systematic review aimed to assess whether published relative PROM improvements with technology use in THA achieved minimal clinically important differences (MCIDs).

METHODS

PubMed/MEDLINE/Cochrane Library were systematically reviewed for studies comparing PROMs for primary N-THA or RA-THA with C-THA as the control group. Relative improvement differences between groups were compared to established MCID values. Reported clinical and radiographic differences were assessed. Review of N-THA and RA-THA literature yielded 6 (n = 2580) and 10 (n = 2786) studies, respectively, for analyses.

RESULTS

Statistically significant improvements in postoperative PROM scores were reported in 2/6 (33.3%) studies comparing N-THA with C-THA, though only 1 (16.7%) reported clinically significant relative improvements. Statistically significant improvements in postoperative PROMs were reported in 6/10 (60.0%) studies comparing RA-THA and C-THA, though none reported clinically significant relative improvements. Improved radiographic outcomes for N-THA and RA-THA were reported in 83.3% and 70.0% of studies, respectively. Only 1 study reported a significant improvement in revision rates with RA-THA as compared to C-THA.

CONCLUSIONS

Reported PROM scores in studies comparing N-THA or RA-THA to C-THA often do not achieve clinically significant relative improvements. Future studies reporting PROMs should be interpreted in the context of validated MCID values to accurately establish the clinical impact of intraoperative technology.

Chronic kidney disease increases cost of care and readmission risk after shoulder arthroplasty

BACKGROUND

Chronic kidney disease (CKD) is associated with adverse outcomes and higher costs after lower extremity arthroplasty from higher rates of infection, aseptic loosening, and transfusion and longer hospital length of stay (LOS). The purpose of this study was to compare health care utilization and 90-day encounter charges after shoulder arthroplasty (SA) in patients with and without renal disease. A secondary aim was to define the characteristics of patients with renal disease.

METHODS

We conducted a retrospective cohort study of all patients who underwent primary SA from January 2015 to December 2019 by a single surgeon at a single institution. Patients without a baseline glomerular filtration rate (GFR) were excluded. We evaluated results for patients with CKD (GFR ≤59 mL/min/1.73 m2) and without CKD (GFR ≥60 mL/min/1.73 m2). Univariate regression was performed to assess the influence of CKD on health care utilization, including LOS, transfusion, and risk for emergency department (ED) revisit or readmission during the 90-day postoperative period. In addition, 90-day encounter charges, revisit charges, and ED charges for patients with CKD were compared with those for patients with normal renal function. Last, multivariable linear regression models were used to assess the effect of estimated GFR on total 90-day encounter charges.

RESULTS

A total of 514 patients met the study inclusion criteria, with 125 having CKD and 389 having normal GFR. Patients with CKD were more likely to require transfusion (odds ratio: 16.2 [confidence interval: 1.9, 139.7], P = .011) despite similar intraoperative estimated blood loss (156.9 ± 132.5 mL vs. 153.8 ± 89.7 mL; P = .768). In addition, patients with CKD had longer LOS (2.8 ± 1.3 days vs. 2.3 ± 1.0 days; P < .001), had higher 90-day readmission rates (P = .001), were more likely to visit the ED within 90 days after SA (P = .018), and had higher total 90-day encounter charges ($37,769 ± $6901 vs. $35,684 ± $5312; P = .001). Each unit increase in eGFR independently reduced total encounter charges by $67 (-$132, -$2; P = .043); dialysis patients incurred higher total 90-day encounter charges compared with patients with less severe renal disease ($42,733 ± $8985 vs. $37,531 ± $6749; P = .002). Also, patients with CKD were older (73.2 ± 8.9 vs. 68.1 ± 9.4 years; P < .001); had a lower preoperative hemoglobin level (12.4 ± 1.5 g/dL vs. 13.4 ± 1.5 g/dL; P < .001), higher American Society of Anesthesiologists score (P < .001), and more preoperative comorbidities (5.9 ± 2.9 vs. 5.0 ± 3.1; P < .001); and were more likely to use opioids preoperatively (P = .043).

CONCLUSION

Patients with CKD have a higher risk for blood transfusion, ED visits, and readmission after SA, with higher total 90-day encounter charges. Identifying and optimizing this patient population before surgery can reduce costs and improve outcomes, which benefits patients, physicians, institutions, and payors.

Observed Differences in Patient Comorbidities and Complications Undergoing Primary Total Joint Arthroplasty Between Non-orthopaedic and Orthopaedic Referral Patients

BACKGROUND

Value-based total joint arthroplasty (TJA) has resulted in decreasing surgeon reimbursement which has created concern that surgeons are being incentivized to avoid medically complex patients. The purpose of this study was to determine if patients who underwent primary total knee (TKA) and total hip arthroplasty (THA) had different comorbidities and complication rates based on referral type: 1) non-orthopaedic referral (NOR), 2) outside orthopaedic referral (OOR) or 3) self-referral (SR).

METHODS

At a single tertiary care centre, patients undergoing primary TJA between July 2019 and January 2020 were identified using current procedural codes. Data were abstracted from the Institutional National Surgical Quality Improvement Program (NSQIP) along with electronic medical records which included referral type, primary insurance, demographics, comorbidities, and comorbidity scores, including an American Society of Anesthesiology (ASA) score. Complications and outcomes were tracked for 90 days post-operatively. Referral groups were compared using Chi-square exact tests for categorical variables and t-tests or Wilcoxon Rank Sum tests for continuous variables, as appropriate.

RESULTS

Of the 393 patients included in this study, there were 249 (63%) NOR, 104 (26%) OOR, and 40 (10%) SR. The OOR versus NOR group had a significantly greater proportion of patients with obesity (79 vs 64%, p=0.047) and an ASA score ≥3 (59 vs 43%, p=0.007). There was a significantly greater proportion of patients with wound complications (10 vs 4%, p=0.023) and ≥2 complications (14 vs 3%, p<0.001) in OOR versus NOR, respectively.

CONCLUSION

Patients who underwent primary TJA and were referred by an orthopaedic surgeon tended to have more comorbid conditions and higher rates of severe complications. The observed difference in referrals may be explained by monetary incentivization in the context of current reimbursement trends. Organizations utilizing bundled payment programs to reimburse surgeons should use a risk-stratification model to mitigate incentivizing surgeons to avoid medically complex patients.

Association Between Hospital Participation in Value-Based Programs and Timely Initiation of Post-Acute Home Health Care, Functional Recovery, and Hospital Readmission After Joint Replacement

OBJECTIVES

This study examined the association between hospital participation in Bundled Payments for Care Improvement (BPCI) or Comprehensive Care for Joint Replacement (CJR) and the timely initiation of home health rehabilitation services for lower extremity joint replacements. Furthermore, this study examined the association between the timely initiation of home health rehabilitation services with improvement in self-care, mobility, and 90-day hospital readmission.

METHOD

This retrospective cohort study used Medicare inpatient claims and home health assessment data from 2016 to 2017 for older adults discharged to home with home health following hospitalization after joint replacement. Multilevel multivariate logistic regression was used to examine the association between hospital participation in BPCI or CJR programs and timely initiation of home health rehabilitation service. A 2-staged generalized boosted model was used to examine the association between delay in home health initiation and improvement in self-care, mobility, and 90-day risk-adjusted hospital readmission.

RESULTS

Compared with patients discharged from hospitals that did not have BPCI or CJR, patients discharged from hospitals with these programs had a lower likelihood of delayed initiation of home health rehabilitation services for both knees and hip replacement. Using propensity scores as the inverse probability of treatment weights, delay in the initiation of home health rehabilitation services was associated with lower improvement in self-care (odds ratio [OR] = 1.23; 95% CI = 1.20-1.26), mobility (OR = 1.15; 95% CI = 1.13-1.18), and higher rate of 90-day hospital readmission (OR = 1.19; 95% CI = 1.15-1.24) for knee replacement. Likewise, delayed initiation of home health rehabilitation services was associated with lower improvement in self-care (OR = 1.16; 95% CI = 1.13-1.20) and mobility (OR = 1.26; 95% CI = 1.22-1.30) for hip replacement.

CONCLUSION

Hospital participation in BPCI or comprehensive CJR was associated with early home health rehabilitation care initiation, which was further associated with significant increases in functional recovery and lower risks of hospital readmission.

IMPACT

Policy makers may consider incentivizing health care providers to initiate early home health services and care coordination in value-based payment models.

Is Tomorrow's Health Care Today: A Look at Current Payment Models for the Future?

The promise of controlling spending and improving the quality of care incentivizes health care providers to prioritize value through alternative payment models. Findings regarding improved value and cost savings of the Comprehensive Care for Joint Replacement (CJR) redesign are consistent throughout selected metropolitan hospitals. Before refinement can take place, reporting on baseline financial status is a necessity to ensure the starting point of hospitals before CJR takes effect. Evidence-based protocols, outcomes-based measures to evaluate results, and cooperation across specialties to deliver high quality care will be necessary to insure improved care throughout the episode. This commentary reviews the CJR program and provides recommendations for the near future in order to best serve the needs of patients as we move forward in the bundled payments direction.

Associations of preoperative anemia and postoperative hemoglobin values with hospital costs in total knee arthroplasty (TKA)

BACKGROUND

Total knee arthroplasty are among the most frequently conducted surgeries, due to an aging society. Since hospital costs are subsequently rising, adequate preparation of patients and reimbursement becomes more and more important. Recent literature revealed anemia as a risk factor for enhanced length of stay (LOS) and complications. This study analyzed whether preoperative hemoglobin (Hb) and postoperative Hb were associated with total hospital costs and general ward costs.

METHODS

The study comprised 367 patients from a single high-volume hospital in Germany. Hospital costs were calculated with standardized cost accounting methods. Generalized linear models were applied to account for confounders, such as age, comorbidities, body mass index, insurance status, health-related quality of life, implant types, incision-suture-time and tranexamic acid.

RESULTS

Preoperative anemic women had 426 Euros higher general ward costs (p < 0.01), due to increased LOS. For men, 1 g/dl less Hb loss between the preoperative value and the value before discharge reduced total costs by 292 Euros (p < 0.001) and 161 Euros fewer general ward costs (p < 0.001). Total hospital costs were reduced by 144 Euros with 1 g/dl higher Hb on day 2 postoperatively for women (p < 0.01).

CONCLUSION

Preoperative anemia was associated with increased general ward costs for women and Hb loss with decreasing total hospital costs for men and women. Cost containment, especially reduced utilization of the general ward, may be feasible with the correction of anemia for women. Postoperative Hb values may be a factor for adjustments of reimbursement systems.

LEVEL OF EVIDENCE

Retrospective cohort study, III.

Initiation of a Comprehensive Early Discharge Program at a Veterans Affairs Hospital

INTRODUCTION

Early discharge protocols have become a major surgical paradigm, but this protocol is not routinely used in the Veteran Affairs (VA) system. The primary objective was to demonstrate the feasibility of a comprehensive joint program (CJP) protocol, including same-day discharge, at a VA hospital. Secondary objectives are to determine whether an increase in postoperative complications, increased readmissions, and increased ER visits compared with previous management protocols occur.

METHODS

A retrospective review of patients undergoing primary total joint arthroplasty conducted before the initiation of CJP was compared with patients undergoing primary total joint arthroplasty conducted after the initiation of CJP. The two cohorts were subdivided further into total knee arthroplasty (TKA) and total hip arthroplasty (THA). Patients' demographics, medical comorbidities, discharge disposition, length of stay (LOS), surgery information, 30-day and 90-day postoperative complications, surgical site infections, and emergency room visits were collected and assessed with paired t -tests.

RESULTS

A total of 200 control cases (101 TKA, 99 THA) were compared with 260 cases (165 TKA, 95 THA) in the CJP group. The mean LOS reduced from 4.38 days in the control group to 0.75 days in the CJP group ( P < 0.001), with 890 total inpatient days in the control group compared with just 200 total inpatient days with the CJP group. A total of 92 patients (34.5%) in the CJP group were discharged the same day compared with 0 in the control group ( P < 0.001). In the control group, 47.8% were discharged to rehabilitation centers compared with only 4.5% in the CJP group ( P < 0.001). The 30-day complication rate was reduced with CJP (5.6% vs. 10.3% control) ( P = 0.028). ER visits did not significantly change (8.9% control vs. 9.3% CJP; P = 0.77).

CONCLUSION

Overall LOS and complication rates were reduced with the CJP, exemplifying the viability of such a protocol in the VA system. In addition, we demonstrated no increased risks accompanied with early discharge to home. This initiative can be used to reduce healthcare dollars in VA healthcare system nationally.

Preoperative Prediction and Risk Factor Identification of Hospital Length of Stay for Total Joint Arthroplasty Patients Using Machine Learning

Background

The aim of this study was to improve understanding of hospital length of stay (LOS) in patients undergoing total joint arthroplasty (TJA) in a high-efficiency, hospital-based pathway.

Methods

We retrospectively reviewed 1401 consecutive primary and revision TJA patients across 67 patient and preoperative care characteristics from 2016 to 2019 from the institutional electronic health records. A machine learning approach, testing multiple models, was used to assess predictors of LOS.

Results

The median LOS was 1 day; outpatients accounted for 16.5%, 1-day inpatient stays for 38.0%, 2-day stays for 26.4%, and 3-days or more for 19.1%. Patients characteristically fell into 1 of 3 broad categories that contained relatively similar characteristics: outpatient (0-day LOS), short stay (1- to 2-day LOS), and prolonged stay (3 days or greater). The random forest models suggested that a lower Risk Assessment and Prediction Tool score, unplanned admission or hospital transfer, and a medical history of cardiovascular disease were associated with an increased LOS. Documented narcotic use for surgery preparation prior to hospitalization and preoperative corticosteroid use were factors independently associated with a decreased LOS.

Conclusions

After TJA, most patients have either an outpatient or short-stay hospital episode. Patients who stay 2 days do not differ substantially from patients who stay 1 day, while there is a distinct group that requires prolonged admission. Our machine learning models support a better understanding of the patient factors associated with different hospital LOS categories for TJA, demonstrating the potential for improved health policy decisions and risk stratification for centers caring for complex patients.

Assessing the predictive capacity of machine learning models using patient-specific variables in determining in-hospital outcomes after THA

Background

Machine learning is a subset of artificial intelligence using algorithmic modeling to progressively learn and create predictive models. Clinical application of machine learning can aid physicians through identification of risk factors and implications of predicted patient outcomes.

Aims

The aim of this study was to compare patient-specific and situation perioperative variables through optimized machine learning models to predict postoperative outcomes.

Methods

Data from 2016 to 2017 from the National Inpatient Sample was used to identify 177,442 discharges undergoing primary total hip arthroplasty, which were included in the training, testing, and validation of 10 machine learning models. 15 predictive variables consisting of 8 patient-specific and 7 situational specific variables were utilized to predict 3 outcome variables: length of stay, discharge, and mortality. The machine learning models were assessed in responsiveness via area under the curve and reliability.

Results

For all outcomes, Linear Support Vector Machine had the highest responsiveness among all models when using all variables. When utilizing patient-specific variables only, responsiveness of the top 3 models ranged between 0.639 and 0.717 for length of stay, 0.703-0.786 for discharge disposition, and 0.887-0.952 for mortality. The top 3 models utilizing situational variables only produced responsiveness of 0.552-0.589 for length of stay, 0.543-0.574 for discharge disposition, and 0.469-0.536 for mortality.

Conclusions

Linear Support Vector Machine was the most responsive machine learning model of the 10 algorithms trained, while decision list was most reliable. Responsiveness was observed to be consistently higher with patient-specific variables than situational variables, emphasizing the predictive capacity and value of patient-specific variables. The current practice in machine learning literature generally deploys a single model, it is suboptimal to develop optimized models for application into clinical practice. The limitation of other algorithms may prohibit potential more reliable and responsive models.Level of Evidence III.

Lessons Learned From the Comprehensive Care for Joint Replacement Model at an Academic Tertiary Center: The Good, the Bad, and the Ugly

BACKGROUND

Our institution participated in the Comprehensive Care for Joint Replacement (CJR) model from 2016 to 2020. Here we review lessons learned from a total joint arthroplasty (TJA) care redesign at a tertiary academic center amid changing: (1) CJR rules; (2) inpatient only rules; and (3) outpatient trends.

METHODS

Quality, financial, and patient demographic data from the years prior to and during participation in CJR were obtained from institutional and Medicare reconciled CJR performance data.

RESULTS

Despite an increase in true outpatients and new challenges that arose from changing inpatient-only rules, there was significant improvement in quality metrics: decreased length of stay (3.48-1.52 days, P < .001), increased home discharge rate (70.2-85.5%, P < .001), decreased readmission rate (17.7%-5.1%, P < .001), decreased complication rate (6.5%-2.0%, P < .001), and the Centers for Medicare and Medicaid Services (CMS) Composite Quality Score increased from 4.4 to 17.6. Over the five year period, CMS saved an estimated $8.3 million on 1,486 CJR cases, $7.5 million on 1,351 non-CJR cases, and $600,000 from the voluntary classification of 371 short-stay inpatients as outpatient-a total savings of $16.4 million. Despite major physician time and effort leading to marked improvements in efficiency, quality, and large cost savings for CMS, CJR participation resulted in a net penalty of $304,456 to our institution, leading to zero physician gainsharing opportunities.

CONCLUSION

The benefits of CJR were tempered by malalignment of incentives among payer, hospital, and physician as well as a lack of transparency. Future payment models should be refined based on the successes and challenges of CJR.

Cemented versus Cementless Femoral Fixation for Elective Primary Total Hip Arthroplasty: A Nationwide Analysis of Short-Term Complication and Readmission Rates

Cementless fixation during total hip arthroplasty (THA) is the predominant mode of fixation utilized for both acetabular and femoral components during elective primary THAs performed in the United States. This study aims to compare early complication and readmission rates between primary THA patients receiving cemented versus cementless femoral fixation. The 2016-2017 National Readmissions Database was queried to identify patients undergoing elective primary THA. Postoperative complication and readmission rates at 30, 90, and 180 days were compared between cemented and cementless cohorts. Univariate analysis was conducted to compare differences between cohorts. Multivariate analysis was performed to account for confounding variables. Of 447,902 patients, 35,226 (7.9%) received cemented femoral fixation, while 412,676 (92.1%) did not. The cemented group was older (70.0 vs. 64.8, p < 0.001), more female (65.0% vs. 54.3%, p < 0.001), and more comorbid (CCI 3.65 vs. 3.22, p < 0.001) compared to the cementless group. On univariate analysis, the cemented cohort had decreased odds of periprosthetic fracture at 30 days postoperatively (OR: 0.556, 95%-CI 0.424-0.729, p < 0.0001), but higher odds of hip dislocation, periprosthetic joint infection, aseptic loosening, wound dehiscence, readmission, medical complications, and death at all timepoints. On multivariate analysis, the cemented fixation cohort demonstrated reduced odds of periprosthetic fracture at all postoperative timepoints: 30 (OR: 0.350, 95%-CI 0.233-0.506, p < 0.0001), 90 (OR: 0.544, 95%-CI 0.400-0.725, p < 0.0001), and 180 days (OR: 0.573, 95%-CI 0.396-0.803, p = 0.002). Cemented femoral fixation was associated with significantly fewer short-term periprosthetic fractures, but more unplanned readmissions, deaths, and postoperative complications compared to cementless femoral fixation in patients undergoing elective THA.

Total hip arthroplasty complications in patients with chronic kidney disease: A comparison study

Background

It has been noted in the literature that there are increased complication rates following total hip arthroplasty (THA) in patients with chronic kidney disease (CKD) or end stage renal disease (ESRD). However, there is little data directly comparing outcomes in patients undergoing THA for osteoarthritis (OA) versus ESRD or CKD with OA. The objective of this study is to illustrate the risk of developing postoperative complications after THA in the CKD and ESRD populations by stage of disease when compared to a control group (OA) and thus better equip orthopaedic providers in the care of these patients.

Methods

The National Inpatient Sample (NIS) was utilized to identify patients undergoing elective THA from 2006 to 2015 with OA, ESRD, and CKD. The prevalence of preoperative comorbidities and the incidence of numerous postoperative complications broken into categories were examined.

Results

Between 2006 and 2015 the NIS database reported 4,350,961 patients diagnosed with OA, 8355 diagnosed with ESRD, and 104,313 diagnosed with CKD undergoing THA. The incidence of wound hematoma (2.5% vs. 0.8%; p < .0001), wound infection (0.7% vs. 0.4%; p = .0319), cardiac (1.3% vs. 0.6%; p = .0067), urinary (3.9% vs. 2.0%; p < .0001), and pulmonary complications (2.2% vs. 0.5%; p < .0001) occurred more frequently in patients with OA and ESRD when compared to only OA patients. For patients with OA and CKD, stages 3-5 saw at least half of the complication categories occur at significantly higher rates than OA patients.

Conclusion

This study shows that patients with ESRD and CKD have increased rates of complications after THA. This study's specific breakdown by stage and complication can benefit orthopaedic surgeons and practitioners in realistic pre and postoperative planning and provides data that could benefit decision making on bundled reimbursement for this specific patient population, as providers could better account for the postoperative complications noted above and their associated costs.

Chronic Obstructive Pulmonary Disease Associated with Prolonged Opiate Use, Increased Short-Term Complications, and the Need for Revision Surgery following Total Knee Arthroplasty

Chronic obstructive pulmonary disease (COPD) is a condition which causes a substantial burden to patients, physicians, and the health care system at large. Medical comorbidities are commonly associated with adverse health outcomes in the postoperative period. Here, we present a large database review of patients undergoing total knee arthroplasty (TKA) to determine the effect of COPD on patient outcomes. The PearlDiver database was queried for all patients who underwent TKA between 2007 and the first quarter of 2017. Medical complications, surgical complications, 30-day readmission rates, revision rates, and opioid utilization were assessed at various intervals following TKA among patients with and without COPD. Multivariable regression was used to calculate adjusted odds ratios controlling for age, sex, and medical comorbidities. A total of 46,769 TKA patients with COPD and 120,177 TKA patients without COPD were studied. TKA patients with COPD experienced increased risk of 30-day readmission (40.8% vs. 32.2%, p < 0.0001), 30-day total medical complications (10.2% vs. 7.0%, p < 0.0001), prosthesis explanation at 6 months (0.4% vs. 0.2, p = 0.0130), 1 year (0.6% vs. 0.3%, p = 0.0005), and 2 years (0.8% vs. 0.5%, p = 0.0003), as well as an increased rate of revision (p < 0.0046) compared to TKA patients without COPD. Opioid utilization of TKA patients with COPD was greater significantly than that of TKA patients without COPD at 3, 6, and 12 months. Patients with COPD have an increased risk for medical and surgical complications, readmission, and prolonged opioid use following TKA.

Payment systems for dialysis and their effects: a scoping review

BACKGROUND

End stage renal disease (ESRD) is a major health concern and a large drain on healthcare resources. A wide range of payment methods are used for management of ESRD. The main aim of this study is to identify current payment methods for dialysis and their effects.

METHOD

In this scoping review Pubmed, Scopus, and Google Scholar were searched from 2000 until 2021 using appropriate search strategies. Retrieved articles were screened according to predefined inclusion criteria. Data about the study characteristics and study results were extracted by a pre-structured data extraction form; and were analyzed by a thematic analysis approach.

RESULTS

Fifty-nine articles were included, the majority of them were published after 2011 (66%); all of them were from high and upper middle-income countries, especially USA (64% of papers). Fee for services, global budget, capitation (bundled) payments, and pay for performance (P4P) were the main reimbursement methods for dialysis centers; and FFS, salary, and capitation were the main methods to reimburse the nephrologists. Countries have usually used a combination of methods depending on their situations; and their methods have been further developed over time specially from the retrospective payment systems (RPS) towards the prospective payment systems (PPS) and pay for performance methods. The main effects of the RPS were undertreatment of unpaid and inexpensive services, and over treatment of payable services. The main effects of the PPS were cost saving, shifting the service cost outside the bundle, change in quality of care, risk of provider, and modality choice.

CONCLUSION

This study provides useful insights about the current payment systems for dialysis and the effects of each payment system; that might be helpful for improving the quality and efficiency of healthcare.

Development of a Novel Prospective Model to Predict Unplanned 90-Day Readmissions After Total Hip Arthroplasty

BACKGROUND

For hospitals participating in bundled payment programs, unplanned readmissions after surgery are often termed "bundle busters." The aim of this study was to develop the framework for a prospective model to predict 90-day unplanned readmissions after elective primary total hip arthroplasty (THA) at a macroscopic hospital-based level.

METHODS

A national, all-payer, inpatient claims and cost accounting database was used. A mixed-effect logistic regression model measuring the association of unplanned 90-day readmissions with a number of patient-level and hospital-level characteristics was constructed.

RESULTS

Using 427,809 unique inpatient THA encounters, 77 significant risk factors across 5 domains (ie, comorbidities, demographics, surgical history, active medications, and intraoperative factors) were identified. The highest frequency domain was comorbidities (64/100) with malignancies (odds ratio [OR] 2.26), disorders of the respiratory system (OR 1.75), epilepsy (OR 1.5), and psychotic disorders (OR 1.5), being the most predictive. Other notable risk factors identified by the model were the use of opioid analgesics (OR 7.3), Medicaid coverage (OR 1.8), antidepressants (OR 1.6), and blood-related medications (OR 1.6). The model produced an area under the curve of 0.715.

CONCLUSION

We developed a novel model to predict unplanned 90-day readmissions after elective primary THA. Fifteen percent of the risk factors are potentially modifiable such as use of tranexamic acid, spinal anesthesia, and opioid medications. Given the complexity of the factors involved, hospital systems with vested interest should consider incorporating some of the findings from this study in the form of electronic medical records predictive analytics tools to offer clinicians with real-time actionable data.

Preoperative Patient Expectation of Discharge Planning is an Essential Component in Total Knee Arthroplasty

Purpose

A better understanding of total knee arthroplasty (TKA) candidate expectations within the perioperative setting will enable clinicians to promote patient-centered practices, optimize recovery times, and enhance quality metrics. In the current study, TKA candidates were surveyed pre- and postoperatively to elucidate the relationship between patient expectations and length of stay (LOS).

Material and methods

This is a prospective study of patients undergoing TKA between December 2017 and August 2018. Patients were electronically administered surveys regarding their discharge plan 10 days pre-/postoperatively. All patients were categorized into three cohorts based on their LOS: 1, 2, and 3+ days. The effect of preoperative discharge education on patient postoperative satisfaction was evaluated.

Results

In total, 221 TKAs were included, of which 83 were discharged on postoperative day (POD) 1, 96 on POD-2, and 42 POD-3+. Female gender, increasing body mass index (BMI), and surgical time correlated with increased LOS. Preoperative discussions regarding LOS occurred in 84.62% (187/221) of patients but did correlate with differences in LOS. However, patients discharged on POD-1 were more inclined to same-day surgery preoperatively. Patients discharged on POD-3+ were found to be more uncomfortable regarding their discharge during the preoperative phase. Multivariable regressions demonstrated that preoperative discharge discussion was positively correlated with home discharge.

Conclusion

Physician-driven discussion regarding patient discharge did not alter patient satisfaction or length of stay but did correlate with improved odds of home discharge. These findings underscore the importance of patient education, shared decision-making, and managing patient expectations.

Liposomal Bupivacaine in Adductor Canal Blocks Before Total Knee Arthroplasty Leads to Improved Postoperative Outcomes: A Randomized Controlled Trial

BACKGROUND

This study compares the use of liposomal bupivacaine (Exparel) versus ropivacaine in adductor canal blocks (ACB) before total knee arthroplasties (TKAs).

METHODS

From the months of April 2020 to September 2021, 147 patients undergoing unilateral primary TKA were asked to participate in this prospective, double-blinded randomized controlled trial. Each patient received an iPACK block utilizing ropivacaine and was additionally randomized to receive an ACB with Exparel or Ropivacaine. For each patient, demographic information, inpatient hospital information, postoperative opioid use, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire scores were collected.

RESULTS

Overall, 100 patients were included (50 in each cohort). The Exparel group had a lower hospital length of stay compared to the Control group (36.3 vs 49.7 hours, P < .01). Patients in the Exparel group reported an increased amount of Numerical Rating Scale pain score improvement at all postoperative timepoints. These patients also used a lower amount of inpatient opioids (40.9 vs 47.3 MME/d, P = .04) but a similar amount of outpatient opioids (33.4 vs 32.1 MME/d, P = .351). Finally, the Exparel group had increased improvements in all WOMAC subscores and total scores at most timepoints compared to the Control group (P < .05).

CONCLUSION

Exparel peripheral regional nerve blocks lead to decreases in pain levels, shorter hospital lengths of stay, inpatient opioid usage, and improved WOMAC scores. Exparel can be safely used in ACB blocks before TKA to help in controlling postoperative pain and decrease length of stay.

An Anesthesia Block Room Is Financially Net Positive for a Hospital Performing Arthroplasty

INTRODUCTION

Regional anesthesia is increasingly used in total joint arthroplasty (TJA). It has shown efficiency benefits as it allows parallel processing of patients in a dedicated block room (BR). However, granular quantification of these benefits to hospital operations is lacking. The goal of this study was to determine the financial effect of establishing a BR using comprehensive operational modeling.

METHODS

A discrete-event simulation model of daily operating room (OR) patient flow for TJA procedures at a mid-sized hospital was developed. Two scenarios were tested: (1) without and (2) with a BR. Scenarios were compared according to staffing requirements, hours/day, and labor costs. The number of ORs and cases varied from 2 to 6 ORs performing 3 to 5 cases. These results were used as the inputs of a discounted cash flow (CF) model. Discounted CF model outputs were CF, net present value, internal rate of return, and return on investment.

RESULTS

Mean time savings of incorporating a BR were 68 min/d (range: 30 to 80 min/d), reducing the OR closing time by 1 hour. Incremental labor costs/day from nurse overtime pay ranged from $2,025 to $10,125 with no BR and $1,595 to $9,045 with a BR, which resulted in an increase in profit/day from $360 to $1,605. The CF/annum was $54,363, the net present value was $213,082, the internal rate of return was 12%, and the return on investment was 43.61%.

DISCUSSION

This study demonstrates that under all scenarios, a BR is more profitable than no BR to a hospital performing TJA via a bundled care or private payer remuneration model. A BR was shown to be financially net positive even when considering the necessary financial investment to establish it. In addition, this study demonstrates the potential of combining discrete-event simulation with financial analyses to assess various operational models of care to improve hospital efficiency, such as dedicated trauma rooms and swing rooms.

LEVEL OF EVIDENCE

Level III.

Surgical Scheduling Impacts Hospital Length of Stay and Associated Healthcare Costs for Patients Undergoing Total Hip and Knee Arthroplasty

BACKGROUND

Surgical scheduling, specifically the day of the week on which surgery is performed, has been associated with various postoperative outcomes in patients undergoing lower extremity joint arthroplasty.

PURPOSE

We sought to investigate surgical scheduling as a potential modifiable factor for patient quality metrics and related costs.

METHODS

In a retrospective prognostic study, all total knee and total hip arthroplasty (TKA/THA) cases that took place in 2017 to 2018 at a multihospital academic health system were queried. Patients were separated by the day of the week the surgery was performed, with Monday/Tuesday compared to Thursday/Friday. Outcomes included length of stay (LOS) (extended LOS defined as 3 days or longer), cost, and complications. Multivariable regression models measured associations between scheduling of surgery and outcomes; odds ratios (OR) and 95% confidence intervals (CIs) are reported.

RESULTS

Overall, 1,571 TKA and 992 THA patients were included (65% and 35%, respectively, performed on Monday/Tuesday and 70% and 30%, respectively, performed on Thursday/Friday). Patients undergoing TKA on Monday/Tuesday versus Thursday/Friday had higher American Society of Anesthesiologists scores (42% vs 33% with score of 3 or higher) but less often an extended LOS (31% vs 54%; adjusted OR: 2.76, 95% CI: 2.22-3.46), lower skilled nursing facility costs (unadjusted mean, $12,515 vs $14,154) and lower home health aide costs (unadjusted mean, $3,793 vs $4,192). Similar patterns were observed in THA patients.

CONCLUSION

These results from institutional data suggest that surgical scheduling is a modifiable factor possibly associated with postoperative outcomes. Furthermore, more rigorous study is warranted.

Defining the minimal clinically important difference for the knee society score following revision total knee arthroplasty

BACKGROUND

No previous study has evaluated the MCID for revision total knee arthroplasty (TKA). This study aimed to identify the MCID for the Knee Society Score (KSS), for revision TKA.

METHODS

Prospectively collected data from 270 patients who underwent revision TKA at a single institution was analysed. Clinical assessment was performed preoperatively, at 6 months and 2 years using Knee Society Function Score (KSFS) and Knee (KSKS) Scores, and Oxford Knee Score (OKS). MCID was evaluated with a three-pronged methodology, using (1) anchor-based method with linear regression, (2) anchor-based method with receiver operating characteristic (ROC) and area under curve (AUC), (3) distribution-based method with standard deviation (SD). The anchors used were improvement in OKS ≥ 5, patient satisfaction, and implant survivorship following revision TKA.

RESULTS

The cohort comprised 70% females, with mean age of 69.0 years, that underwent unilateral revision TKA. The MCID determined by anchor-based linear regression method using OKS was 6.3 for KSFS, and 6.6 for KSKS. The MCID determined by anchor-based ROC was between 15 and 20 for KSFS (AUC: satisfaction = 71.8%, survivorship = 61.4%) and between 33 and 34 for KSKS (AUC: satisfaction = 76.3%, survivorship = 67.1%). The MCID determined by distribution-based method of 0.5 SD was 11.7 for KSFS and 11.9 for KSKS.

CONCLUSION

The MCID of 6.3 points for KSFS, and 6.6 points for KSKS, is a useful benchmark for future studies looking to compare revision against primary TKA outcomes. Clinically, the MCID between 15 and 20 for KSFS and between 33 and 34 for KSKS is a powerful tool for discriminating patients with successful outcomes after revision TKA. Implant survivorship is an objective and naturally dichotomous outcome measure that complements the subjective measure of patient satisfaction, which future MCID studies could consider utilizing as anchors in ROC.

LEVEL OF EVIDENCE

II.

Understanding Health Economics in Joint Replacement Surgery

The number of arthroplasty procedures has been rising at a significant rate, contributing to a notable portion of the nation's health care spending. This growth has contributed to an increase in the number of health care economic studies in the field of adult reconstruction surgery. Although these articles are filled with important information, they can be difficult to understand without a background in business or economics. The goal of this review is to define the common terminology used in health care economic studies, assess their value and benefit in the context of total joint arthroplasty, and highlight shortcomings in the current literature. [Orthopedics. 2022;45(4):e174-e182.].

The Significance of Race/Ethnicity and Income in Predicting Preoperative Patient-Reported Outcome Measures in Primary Total Joint Arthroplasty

BACKGROUND

Utilization of total joint arthroplasty (TJA) by minorities is disproportionately low compared to Whites. Contributing factors include poorer outcomes, lower expectations, and decreased access to care. This study aimed to evaluate if race and income were predictive of preoperative patient-reported outcome measures (PROMs) and the likelihood of achieving the minimal clinically important difference (MCID) following TJA.

METHODS

We retrospectively reviewed 1,371 patients who underwent primary TJA between January 2018 and March 2021 in a single healthcare system. Preoperative and postoperative PROM scores were collected for Patient-Reported Outcomes Measurement Information System (PROMIS) Mental Health, PROMIS Physical Function (PF10a), and either Knee injury and Osteoarthritis Outcome Score (KOOS) or Hip disability and Osteoarthritis Outcome Score (HOOS). Demographic and comorbidity data were included as explanatory variables. Multivariable regression was used to analyze the association between predictive variables and PROM scores.

RESULTS

Mean preoperative PROM scores were lower for non-Whites compared to Whites. Increased median household income was associated with higher preoperative PROM scores. Non-White race was associated with lower PROMIS Mental Health and KOOS, but not PF10a or HOOS scores. Only non-White race was associated with a decreased likelihood of achieving MCID for PF10a. Neither race nor income was predictive of achieving MCID for KOOS and HOOS.

CONCLUSION

Non-White race/ethnicity and lower income were associated with lower preoperative PROMs prior to primary TJA. Continued research is necessary to identify the causes of this discrepancy and correct this disparity.

Complications During the Hospital Stay, Length of Stay, and Cost of Care in Parkinson Patients Undergoing Total Knee Arthroplasty: A Propensity Matched Database Study

Patients with Parkinson disease (PD) undergoing total knee arthroplasty (TKA) can present with a unique subset of challenges during their hospital stay. The literature is limited to single-center studies with a small number of patients. This study was aimed to analyze the inpatient complications, length of stay (LOS), and cost of care (COC) associated after TKA with PD over 4 years (2016 to 2019).

Effects of Preoperative Carbohydrate-rich Drinks on Immediate Postoperative Outcomes in Total Knee Arthroplasty: A Randomized Controlled Trial

BACKGROUND

This study investigates the effects of preoperative carbohydrate-rich drinks on postoperative outcomes after primary total knee arthroplasty.

METHODS

We prospectively randomized 153 consecutive patients undergoing primary total knee arthroplasty at one institution. Patients were assigned to one of three groups: group A (50 patients) received a carbohydrate-rich drink; group B (51 patients) received a placebo drink; and group C (52 patients) did not receive a drink (control). All healthcare personnel and patients were blinded to group allocation. Controlling for demographics, we analyzed the rate of postoperative nausea and vomiting, length of stay, opiate consumption, pain scores, serum glucose, adverse events, and intraoperative and postoperative fluid intake.

RESULTS

Demographics and comorbidities were similar among the groups. There were no significant differences in surgical interventions or experience. Surgical fluid intake and total blood loss were similar among the three groups (P = 0.47, P = 0.23). Furthermore, acute postoperative outcomes (ie, pain, episodes of nausea, and length of stay) were similar across all three groups. There were no significant differences in adverse events between the three groups (P = 0.13). There was a significant difference in one-time postoperative bolus between the three groups (P = 0.02), but after multivariate analysis, it did not demonstrate significance. None of the intervention group were readmitted, whereas 5.9% and 11.5% were readmitted in the placebo and control groups, respectively (P = 0.047). The chance of 90-day readmission was reduced in group A compared with group C (odds ratio, 0.08; 95% confidence interval, 0.01 to 0.72; P = 0.02). There were no differences in other postoperative outcome measurements.

CONCLUSION

This randomized controlled trial demonstrated that preoperative carbohydrate loading does not improve immediate postoperative outcomes, such as nausea and vomiting; however, it demonstrated that consuming fluid preoperatively proved no increased risk of adverse outcomes and there was a trend toward decrease of one-time boluses postoperatively.

CLINICAL TRIALS REGISTRY

NCT03380754.

An Academic Orthopaedic Specialty Hospital Provides the Shortest Operative Times within a Single Health System for Primary and Revision Total Knee Arthroplasty

The study aimed to optimize value-based health care practices in total joint arthroplasty (TJA), and we need to understand how the surgical setting can influence efficiency of care. While this has previously been investigated, the purpose of this study was to clarify if these findings are generalizable to an institution with an orthopaedic specialty hospital. A retrospective review was conducted of 6,913 patients who underwent primary or revision total knee arthroplasty (TKA) at one of four hospitals within a single, urban, and academic health system: a high volume academic (HVA) hospital, a low volume academic (LVA) hospital, a high volume community (HVC) hospital, or a low volume community (LVC) hospital. Patient demographics were collected in an arthroplasty database, as were operating room (OR) times and several specific time points during the surgery. The HVA (orthopaedic specialty) hospital had the shortest total primary TKA OR times and the LVC that had the longest times (156.69 vs. 174.68, p < 0.0001). The HVA hospital had the shortest total revision TKA OR times, and the LVC had the longest times (158.20 vs. 184.95, p < 0.0001). In our health system, the HVA orthoapedic specialty hospital had the shortest overall OR time, even when compared with the HVC hospital. This is in contradistinction to prior findings that HVC institutions had the shortest OR times in a health system that did not have an orthopaedic specialty hospital. This provides evidence that an orthopaedic specialty hospital can be a model for efficient care, even at an academic teaching institution.

Same-Day Outpatient Lower-Extremity Joint Replacement: A Critical Analysis Review

➢ The economics of transitioning total joint arthroplasty (TJA) to standalone ambulatory surgery centers (ASCs) should not be capitalized on at the expense of patient safety in the absence of established superior patient outcomes. ➢ Proper patient selection is essential to maximizing safety and avoiding complications resulting in readmission. ➢ Ambulatory TJA programs should focus on reducing complications frequently associated with delays in discharge. ➢ The transition from hospital-based TJA to ASC-based TJA has substantial financial implications for the hospital, payer, patient, and surgeon.

Predictive capacity of four machine learning models for in-hospital postoperative outcomes following total knee arthroplasty

Background

Machine learning (ML) methods have shown promise in the development of patient-specific predictive models prior to surgical interventions. The purpose of this study was to develop, test, and compare four distinct ML models to predict postoperative parameters following primary total knee arthroplasty (TKA).

Methods

Data from the Nationwide Inpatient Sample was used to identify patients undergoing TKA during 2016-2017. Four distinct ML models predictive of mortality, length of stay (LOS), and discharge disposition were developed and validated using 15 predictive patient and hospital-specific factors. Area under the curve of the receiver operating characteristic curve (AUCROC) and accuracy were used as validity metrics, and the strongest predictive variables under each model were assessed.

Results

A total of 305,577 patients were included. For mortality, the XGBoost, neural network (NN), and LSVM models all had excellent responsiveness during validation, while random forest (RF) had fair responsiveness. For predicting LOS, all four models had poor responsiveness. For the discharge disposition outcome, the LSVM, NN, and XGBoost models had good responsiveness, while the RF model had poor responsiveness. LSVM and XGBoost had the highest responsiveness for predicting discharge disposition with an AUCROC of 0.747.

Discussion

The ML models tested demonstrated a range of poor to excellent responsiveness and accuracy in the prediction of the assessed metrics, with considerable variability noted in the predictive precision between the models. The continued development of ML models should be encouraged, with eventual integration into clinical practice in order to inform patient discussions, management decision making, and health policy.

Bisphosphonates in Total Joint Arthroplasty: A Review of Their Use and Complications

Background

Considerable interest has been expressed in the use of bisphosphonates to treat periprosthetic osteoporosis with the clinical goals of reducing periprosthetic fractures and prolonging implant survival.

Methods

A systematic review was performed with the goal of identifying both basic science and clinical studies related to the risks and benefits of bisphosphonate use in total joint arthroplasty.

Results

Studies have shown that bisphosphonates may increase early bony ingrowth, decrease the postoperative loss of bone mineral density, and increase the longevity of implants by reducing the need for revisions secondary to aseptic loosening. Continuing bisphosphonates for 1 year postoperatively seems to provide the greatest benefit, with only marginal benefit being shown by continuing therapy for up to 2 years. Current data present some concerns for an increased risk of periprosthetic fractures especially in younger patients, and prolonged therapy is not recommended due to the potential risk of atypical femur fractures. Patients should be counseled regarding the risk of side effects of bisphosphonates, including the risk of osteonecrosis of the jaw, which is a rare but serious side effect. They should also be counseled on the risk of atypical femur fractures and gastrointestinal intolerance.

Conclusions

Orthopedic surgeons could consider bisphosphonates for up to 1 year postoperatively regardless of the patient’s prior bone mineral density, after discussion regarding the risks and benefits with the patient.

Increased Complications in Octogenarians Undergoing Same-Day Discharge following Total Knee Arthroplasty: A Matched Cohort Analysis

Same-day discharge pathways in total knee arthroplasty (TKA) are gaining popularity as a means to increase patient satisfaction and reduce overall costs, but these pathways have not been thoroughly evaluated in potentially at-risk populations, such as in patients ≥80 years old. The purpose of this study was to compare 90-day complications and mortality following same-day discharge after primary TKA in patients ≥80 years old and those <80 years old. Patients who underwent unilateral primary TKA, were discharged on postoperative day 0, and had a minimum 90-day follow-up were identified in a national insurance claims database (PearlDiver Technologies) using Current Procedural Terminology code 27447. These patients were stratified into two cohorts based upon age: (1) nonoctogenarians (<80 years old) and (2) octogenarians (≥80 years old). These cohorts were propensity matched based upon sex, Charlson comorbidity index, and obesity status. Univariate analysis was performed to determine differences in 90-day complications and mortality between the two cohorts. In total, 1,111 patients were included in each cohort. Both cohorts were successfully matched, with no observed differences in matched parameters for demographics or comorbidities. There was no significant difference in 90-day mortality between the two cohorts (p = 0.896). However, octogenarians were at significantly increased risk of postoperative atrial fibrillation (20.8 vs. 10.4%; p < 0.001), nonatrial fibrillation arrhythmias (8.4 vs. 5.6%; p = 0.009), pneumonia (4.5 vs. 2.2%; p = 0.002), stroke (3.1 vs. 1.7%; p = 0.037), heart failure (10.5 vs. 7.5%; p = 0.012), and urinary tract infection (UTI; 14.3 vs. 9.4%; p < 0.001) compared with the nonoctogenarian cohort. Relative to matched controls, octogenarians were at significantly increased risk of numerous 90-day medical complications following same-day primary TKA, including cardiopulmonary complications, stroke, and UTI. Clinicians should be cognizant of these complications and counsel patients appropriately when electing to perform same-day TKA in the octogenarian population.

Are Morbidly Obese Patients Equally Benefitting From Care Improvements in Total Hip Arthroplasty?

BACKGROUND

Morbidly obese patients have increased rates of complications following primary total hip arthroplasty (THA) and it is not clear whether improvements in THA care pathways are equally benefitting these patients. The purpose of this study is to assess if reductions in complications have similarly improved for both morbidly obese and non-morbidly obese patients after THA.

METHODS

Patients undergoing primary THA between 2011 and 2019 were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Patients were stratified by body mass index (BMI) <40 and ≥40 kg/m². Thirty-day rates of infectious complications, readmissions, reoperation, and any complication were assessed. Trends in complications were compared utilizing odds ratios and multivariate analyses.

RESULTS

In total, 234,334 patients underwent THA and 16,979 (7.8%) had BMI ≥40 kg/m². Patients with BMI ≥40 kg/m² were at significantly higher odds for readmission, reoperation, and infectious complications. Odds for any complication were lower for morbidly obese patients in 2011, not different from 2012 to 2014, and higher from 2015 to 2019 compared to lower BMI patients. Odds for any non-transfusion complication were higher for morbidly obese patients and there was no improvement for either group over the study period. There were improvements in rates of readmission and reoperation for patients with BMI <40 kg/m² and readmission for BMI >40 kg/m².

CONCLUSION

Odds for readmission and reoperation for non-morbidly obese patients and readmission for morbidly obese patients improved from 2011 to 2019. Reductions in transfusions are largely responsible for improvements in overall complication rates. Although morbidly obese patients remain at higher risk for complications, there does not appear to be a growing disparity in outcomes between morbidly obese and non-morbidly obese patients.

Opioid-Prescribing Practices Between Total Knee and Hip Arthroplasty in an Outpatient Versus Inpatient Setting

ABSTRACT

Despite trends showing increases in the utilization of outpatient (OP) ambulatory surgery centers (ASCs) and decreases in the utilization of inpatient (IP) facilities for total knee arthroplasty (TKA) and total hip arthroplasty (THA), little is known about opioid prescribing for these procedures between each setting. This study evaluated differences in opioid prescribing and consumption between OP ASC and IP settings for elective TKA and THA surgeries over a 1-year period. Data collection also included pain and satisfaction of pain control postsurgery. In an OP ASC, analysis revealed a significant decrease in pills prescribed (p < .001, p < .001) and consumed (p < .001, p < .001) for TKA and THA, respectively. There was a significant decrease in the morphine equivalence units prescribed (p < .001, p < .001) and consumed (p < .001, p < .001) for TKA and THA, respectively. For TKA, pain was significantly lower (p = .018) and satisfaction of pain control was significantly higher (p = .007). For THA, pain (p = .374) and satisfaction of pain control (p = .173) were similar between the settings. Benefits of performing these surgeries in an OP ASC setting are patients having similar or lower levels of pain and having similar or higher satisfaction of pain control. Patients are also prescribed and consume less opioids. This has important implications for healthcare systems.

Recent Increases in Outpatient Total Hip Arthroplasty Have Not Increased Early Complications

BACKGROUND

Outpatient total hip arthroplasty (THA) has increased in recent years. Recent regulatory changes may allow and incentivize outpatient THA in more patients; however, there are concerns regarding safety. The purpose of this study is to assess early complications in outpatient THA compared to longer hospitalization.

METHODS

We identified patients undergoing primary THA in the National Surgical Quality Improvement Program database between 2015 and 2018. Patients were stratified by length of stay (LOS): 0 days (LOS 0), 1-2 days, and ≥3 days. Thirty-day rates of any complication, wound complications, readmissions, and reoperation were assessed. Multivariate analysis was performed.

RESULTS

In total, 4813 (4%) patients underwent outpatient THA, 84,627 (64%) had LOS of 1-2 days, and 42,293 (32%) had LOS ≥3 days. LOS 0 patients were younger, had lower body mass index, and less medical comorbidities compared to those with postsurgical hospitalization. Any complication was experienced in 3.2% of the LOS 0 group, 5.3% of the LOS 1-2 group, and 15.6% for the LOS ≥3 group (P < .0001). Readmission rates were 1.6%, 2.6%, and 4.7% for the 3 groups, respectively (P < .0001). After controlling for confounding variables, patients with LOS 1-2 days had higher odds for any complication (odds ratio 1.56 [1.32-1.83) and readmission (odds ratio 1.41 [1.12-1.78]) compared to LOS 0 days. Patients with LOS ≥3 days had higher odds for complications compared to LOS 0 or 1-2 days.

CONCLUSION

Outpatient THA had lower odds for readmission or complications compared to LOS 1-2 days. Despite increased outpatient surgery, many patients had postsurgical hospitalization and, due to patient factors, this remains an integral patient of post-THA care.

Access to Total Knee Arthroplasty Among Patients With Low Incomes Has Not Increased Under Global Budget Revenue

In 2014, Maryland implemented an experimental reimbursement model, Global Budget Revenue (GBR). This model provided hospitals with a capitated annual budget each fiscal year to use toward all services, regardless of payer. Goals of GBR include reductions in cost, improvements in care quality, and increased access for patients to high-volume procedures, such as total knee arthroplasty (TKA). We assessed demographics and outcomes among patients with low incomes and patients of racial minority groups in Maryland who underwent TKA before and after GBR implementation. Patients undergoing TKAs from 2011 to 2016 were queried from the Maryland State Inpatient Database, resulting in 71,066 patients. There were 13,722 patients with low incomes and 19,846 patients of racial minority groups. The chi-square test was used for sex, income, insurance, Charlson Comorbidity Index, and morbid obesity, with the Student's t test being reserved for age before and after GBR. The proportion of patients with low incomes decreased the year before GBR but increased with GBR and maintained (P<.001). The proportion of patients of racial minority groups increased the year before GBR implementation, decreased slightly, and then maintained (P<.001). Mean cost decreased for both cohorts of patients (both P<.001). Discharges to home increased for both cohorts (P<.001), while length of stay decreased (both P<.001). Global Budget Revenue decreased cost while improving outcomes for TKA patients post-GBR. Patients with low incomes have not increased their use of TKA, contrary to patients of racial minority groups. This suggests that barriers remain. Further follow-up of GBR performance in subsequent years will increase understanding of the sustainability of this trend and the degree to which any increase in access is dependent on the implementation of the Affordable Care Act. [Orthopedics. 2022;45(1):e11-e16.].

Longer Length of Stay Is Associated With More Early Complications After Total Knee Arthroplasty

Background

Length of stay (LOS) following total knee arthroplasty (TKA) has decreased over recently years. In 2018, the Centers for Medicare and Medicaid Services removed TKA from Inpatient-Only List (IPO), incentivizing further expansion of outpatient TKA. However, many patients may still require postsurgical hospitalization. The purpose of this study was to assess early outcomes for TKA based on length of stay (LOS).

Methods

We identified patients undergoing elective, primary TKA in the National Surgical Quality Improvement Program database using CPT code 27447 between 2015 and 2018. Patients were stratified by length of stay (LOS) 0 days, 1-2 days, and ≥3 days. Thirty-day rates of any complication, wound complications, readmission, and reoperation were assessed. Multivariate analysis was performed to adjust for confounding variables.

Results

5,655 (3%) patients underwent outpatient TKA, 130,543 (59%) had LOS 1-2 days, and 84,986 (38%) had LOS ≥3 days. Any complication was experienced in 4.1% of those with LOS 0 days, 4.3% for those with LOS of 1-2 days, and 10.5% for patients with LOS ≥3 days (p<0.0001). Readmission occurred in 2.2%, 2.6%, and 4.0% for the 3 groups, respectively (p<0.0001). After multivariate analysis, there was no significant difference in any outcome measure between patients with LOS 0 and 1-2 days, however those with LOS ≥3 days had higher odds of complications, reoperation, and readmission.

Conclusion

A significant number of patients had LOS ≥3 days following TKA and had more comorbidities and complications. Outpatient TKA was not associated with increased early complication compared to those with LOS of 1-2 days. Despite expansion of outpatient surgery, postsurgical hospitalization remains an integral part of care following TKA. Level of Evidence: III.

The Impact of Total Joint Arthroplasty on Long-Term Physical Activity: A Secondary Analysis of the Health and Retirement Study

OBJECTIVE

Physical inactivity is the fourth-leading cause of global mortality and is prevalent among people with lower extremity osteoarthritis. Lower extremity osteoarthritis is the most common arthritis type afflicting older adults, and total joint arthroplasty (TJA) performed to address the condition is Medicare's largest annual expense. Despite TJA intervention to address the disabling effects of osteoarthritis, physical activity (PA) level remains stable 6 months after TJA; however, the effect of TJA on long-term PA $(\ge$2 y) in a representative sample of older adults is unknown. The purpose of this study was to test the hypothesis that PA would remain stable in the long term.

METHODS

In this longitudinal observational study, a probability-weighted difference-in-differences analysis was conducted to observe the predictive margins of nontraumatic hip or knee TJA on levels of vigorous and moderate PA after 2 years. A combined Health and Retirement Study data set of community-dwelling adults who were >55 years old, had symptomatic osteoarthritis, and were in need of TJA between 2008 and 2018 (N = 4652) was used.

RESULTS

TJA was not associated with vigorous PA ($\delta$ = 2.37; SE = 5.23) or moderate PA ($\delta$ = -2.84; SE = 7.76) after 2 years.

CONCLUSION

TJA was not associated with increased long-term PA in older adults with osteoarthritis.

IMPACT

Physical therapists should not assume that there will be a natural increase in PA after functional recovery from TJA procedures. Older adults with lower extremity osteoarthritis may benefit from PA screening and promotion practices in physical therapy services.

LAY SUMMARY

Receiving a total joint replacement does not lead to increased physical activity levels 2 years after surgery.

Regional Implicit Bias Does Not Account for Racial Disparity in Total Joint Arthroplasty Utilization

BACKGROUND

Racial disparities surrounding the utilization of total hip and total knee arthroplasty (THA, TKA) are well documented. The Implicit Association Test (IAT) is a validated tool used to measure implicit and explicit bias. The purpose of this study is to evaluate if variations in IAT scores by geographical region in the United States (US) correspond with regional variations in THA and TKA utilization by blacks compared to whites.

METHODS

Data from the US Census and National Inpatient Sample from 2012 to 2014 were used to calculate THA and TKA utilization rates among Medicare-aged blacks and whites. Data were aggregated by US Census Bureau Division. Regional implicit bias was assessed by calculating a weighted average of IAT scores for each division.

RESULTS

Across all geographic regions and years, the surveyed population demonstrated an implicit bias favoring whites over blacks. The population adjusted ratio of white-to-black utilization of THA and TKA by geographic division varied between 0.86-1.85 and 0.87-2.01, respectively. The difference in utilization between geographic divisions reached statistical significance (P < .001). No correlation was found between the IAT scores and race-specific utilization ratios among geographic divisions.

CONCLUSION

Implicit bias as measured by regional IAT did not reflect THA and TKA utilization disparities. The racial disparity in utilization of THA and TKA significantly varied between divisions. The observed disparity was greater in divisions with a relatively higher proportion of blacks. To the authors' knowledge, this is the first study to evaluate the impact of implicit bias on utilization of THA and TKA.

The burden of prosthetic hip dislocations in the United States is projected to significantly increase by 2035

INTRODUCTION

Prosthetic hip dislocation is a common, costly complication of total hip arthroplasty (THA). Despite this, the national burden of prosthetic hip dislocations remains uncharacterised in the United States, especially pertaining to injuries occurring years after the index procedure. This study examines historical and projected national estimates of prosthetic hip dislocations presenting to U.S. emergency departments between 2000 and 2035.

METHODS

We conducted a cross-sectional, retrospective epidemiological study using narratives in the National Electronic Injury Surveillance System (NEISS) database (2000-2017) to identify an estimated 64,671 prosthetic hip implant dislocations presenting to U.S. emergency departments. Estimates for the prevalence of individuals living with a total hip implant were derived from the literature.

RESULTS

The national estimate of prosthetic hip dislocations presenting to U.S. emergency departments rose significantly (p < 0.001) between 2000 (n = 2395; 95% CI, 1264-3526) and 2017 (n = 8094; 95% CI, 4276-11,912). These increases are likely driven by increased numbers of people living with THA overall, since between 2000 and 2017, the average incidence of prosthetic hip dislocation (0.14%; CI 0.08-0.21%) in patients living with hip implants has not changed significantly. Linear regression modeling (R² = 0.7, p < 0.01) projected an increasing number of dislocations through 2035, predicting 10,446 national cases per year by this date.

CONCLUSIONS

Driven by increases in THA, the annual volume of prosthetic hip dislocations presenting to U.S. emergency departments has increased significantly since 2000 and is projected to continue to rise sharply. Future advances in surgical technique, prosthesis design, and injury prevention policies aimed at decreasing the rate of THA dislocation would help alleviate this mounting national health burden.

Patient Willingness to Pay for Faster Return to Work or Smaller Incisions

Background: Value-based health care models such as bundled payments and accountable care organizations can penalize health systems and physicians for excess costs leading to low-value care. Health systems can minimize these extra costs by constraining diagnostic (eg, magnetic resonance imaging utilization) or treatment options with debatable necessity in the setting of clinical equipoise. Instead of restricting more expensive treatments, it is plausible that health systems could instead recoup the extra costs of these treatments by charging patients supplementary out-of-pocket charges (cost sharing). The primary aim of this exploratory study was to assess hand surgery patient willingness to pay supplementary out-of-pocket charges for a procedure that theoretically leads to an earlier return to work or smaller incisions when there are 2 procedures that lead to similar results (clinical equipoise). Methods: A total of 122 patients completed a questionnaire that included demographic information, a financial distress assessment, a series of scenarios asking patients the degree to which they are willing to pay extra for the procedure choice, as well as their perspective of how much insurers should be responsible for these additional costs. Results: Patients were willing to pay out-of-pocket to some degree for a procedure that leads to earlier return to work and smaller incision size when compared with a similar alternative procedure, but noted that insurers should bear a greater burden of costs. Approximately 10% of patients were willing to pay maximum amounts ($2500+) for earlier return to work (3, 7, and 14 days earlier) and smaller incision sizes of any length. Conclusions: Some patients may be willing to pay out-of-pocket and cost share for procedures that lead to earlier return to work and smaller incisions in the setting of clinical equipoise. As such, when developing and implementing alternative payment models, health systems could potentially offer services with debatable necessity in the setting of equipoise for a supplementary out-of-pocket charge.

Is There An Association Between Bundled Payments and "Cherry Picking" and "Lemon Dropping" in Orthopaedic Surgery? A Systematic Review

BACKGROUND

The goal of bundled payments-lump monetary sums designed to cover the full set of services needed to provide care for a condition or medical event-is to provide a reimbursement structure that incentivizes improved value for patients. There is concern that such a payment mechanism may lead to patient screening and denying or providing orthopaedic care to patients based on the number and severity of comorbid conditions present associated with complications after surgery. Currently, however, there is no clear consensus about whether such an association exists.

QUESTIONS/PURPOSES

In this systematic review, we asked: (1) Is the implementation of a bundled payment model associated with a change in the sociodemographic characteristics of patients undergoing an orthopaedic procedure? (2) Is the implementation of a bundled payment model associated with a change in the comorbidities and/or case-complexity characteristics of patients undergoing an orthopaedic procedure? (3) Is the implementation of a bundled payment model associated with a change in the recent use of healthcare resources characteristics of patients undergoing an orthopaedic procedure?

METHODS

This systematic review was registered in PROSPERO before data collection (CRD42020189416). Our systematic review included scientific manuscripts published in MEDLINE, Embase, Web of Science, Econlit, Policyfile, and Google Scholar through March 2020. Of the 30 studies undergoing full-text review, 20 were excluded because they did not evaluate the outcome of interest (patient selection) (n = 8); were editorial, commentary, or review articles (n = 5); did not evaluate the appropriate intervention (introduction of a bundled payment program) (n = 4); or assessed the wrong patient population (not orthopaedic surgery patients) (n = 3). This led to 10 studies included in this systematic review. For each study, patient factors analyzed in the included studies were grouped into the following three categories: sociodemographics, comorbidities and/or case complexity, or recent use of healthcare resources characteristics. Next, each patient factor falling into one of these three categories was examined to evaluate for changes from before to after implementation of a bundled payment initiative. In most cases, studies utilized a difference-in-difference (DID) statistical technique to assess for changes. Determination of whether the bundled payment initiative required mandatory participation or not was also noted. Scientific quality using the Adapted Newcastle-Ottawa Scale had a median (range) score of 8 (7 to 8; highest possible score: 9), and the quality of the total body of evidence for each patient characteristic group was found to be low using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool. We could not assess the likelihood of publication using funnel plots because of the variation of patient factors analyzed in each study and the heterogeneity of data precluded a meta-analysis.

RESULTS

Of the nine included studies that reported on the sociodemographic characteristics of patients selected for care, seven showed no change with the implementation of bundled payments, and two demonstrated a difference. Most notably, the studies identified a decrease in the percentage of patients undergoing an orthopaedic operative intervention who were dual-eligible (range DID estimate -0.4% [95% CI -0.75% to -0.1%]; p < 0.05 to DID estimate -1.0% [95% CI -1.7% to -0.2%]; p = 0.01), which means they qualified for both Medicare and Medicaid insurance coverage. Of the 10 included studies that reported on comorbidities and case-complexity characteristics, six reported no change in such characteristics with the implementation of bundled payments, and four studies noted differences. Most notably, one study showed a decrease in the number of treated patients with disabilities (DID estimate -0.6% [95% CI -0.97% to -0.18%]; p < 0.05) compared with before bundled payment implementation, while another demonstrated a lower number of Elixhauser comorbidities for those treated as part of a bundled payment program (before: score of 0-1 in 63.6%, 2-3 in 27.9%, > 3 in 8.5% versus after: score of 0-1 in 50.1%, 2-3 in 38.7%, > 3 in 11.2%; p = 0.033). Of the three included studies that reported on the recent use of healthcare resources of patients, one study found no difference in the use of healthcare resources with the implementation of bundled payments, and two studies did find differences. Both studies found a decrease in patients undergoing operative management who recently received care at a skilled nursing facility (range DID estimate -0.50% [95% CI -1.0% to 0.0%]; p = 0.04 to DID estimate: -0.53% [95% CI -0.96% to -0.10%]; p = 0.01), while one of the studies also found a decrease in patients undergoing operative management who recently received care at an acute care hospital (DID estimate -0.8% [95% CI -1.6% to -0.1%]; p = 0.03) or as part of home healthcare (DID estimate -1.3% [95% CI -2.0% to -0.6%]; p < 0.001).

CONCLUSION

In six of 10 studies in which differences in patient characteristics were detected among those undergoing operative orthopaedic intervention once a bundled payment program was initiated, the effect was found to be minimal (approximately 1% or less). However, our findings still suggest some level of adverse patient selection, potentially worsening health inequities when considered on a large scale. It is also possible that our findings reflect better care, whereby the financial incentives lead to fewer patients with a high risk of complications undergoing surgical intervention and vice versa for patients with a low risk of complications postoperatively. However, this is a fine line, and it may also be that patients with a high risk of complications postoperatively are not being offered surgery enough, while patients at low risk of complications postoperatively are being offered surgery too frequently. Evaluation of the longer-term effect of these preliminary bundled payment programs on patient selection is warranted to determine whether adverse patient selection changes over time as health systems and orthopaedic surgeons become accustomed to such reimbursement models.

The oxford knee score minimal clinically important difference for revision total knee arthroplasty

BACKGROUND

Minimal clinically important difference (MCID) is crucial for interpreting meaningful improvements in patient-reported outcome measures (PROMs). No previous study has evaluated the MCID for the Oxford Knee Score (OKS) in revision total knee arthroplasty (TKA). This study aimed to propose the OKS MCID for revision TKA.

METHODS

Prospectively collected data from 191 patients who underwent revision TKA at a single institution was analysed. Clinical assessment was performed preoperatively and at 2 years using OKS and Short-Form 36 Physical Component Score (SF-36 PCS). MCID was evaluated with a three-pronged methodology, using (1) anchor-based method with linear regression, (2) anchor-based method with receiver operating characteristic (ROC) and area under curve (AUC), (3) distribution-based method with standard deviation (SD). The anchors used were improvement in SF-36 PCS ≥ 12, patient satisfaction, and implant survivorship following revision TKA.

RESULTS

The MCID determined by anchor-based linear regression method using improvements in SF-36 PCS was 4.9 points. The MCID determined by anchor-based ROC was 10.5 points for satisfaction (AUC = 74.8%) and 13.5 points for implant survivorship (AUC = 73.7%). The MCID determined by distribution-based method of 0.5 SD was 4.7.

CONCLUSION

The proposed MCID for OKS following revision TKA is 4.9 points. Patients who achieve an improvement in OKS of at least 10.5-13.5 points by 2 years are likely to be satisfied with their surgery and not require a subsequent re-revision TKA. Patients undergoing revision TKA should aim for an improvement in OKS of at least 10.5-13.5 points as a target score.

Robotic-assisted total hip arthroplasty: an economic analysis

Aim: To evaluate 90-day episode-of-care (EOC) resource consumption in robotic-assisted total hip arthroplasty (RATHA) versus manual total hip arthroplasty (mTHA). Methods: THA procedures were identified in Medicare 100% data. After propensity score matching 1:5, 938 RATHA and 4,670 mTHA cases were included. 90-day EOC cost, index costs, length of stay and post-index rehabilitation utilization were assessed. Results: RATHA patients were significantly less likely to have post-index inpatient rehabilitation or skilled nursing facility admissions and used fewer home health agency visits, compared with mTHA patients. Total 90-day EOC costs for RATHA patients were found to be US$785 less than those of mTHA patients (p = 0.0095). Conclusion: RATHA was associated with an overall lower 90-day EOC cost when compared with mTHA. The savings associated with RATHA were driven by reduced utilization and cost of post-index rehabilitation services.

Emergency Use of a Custom Distal Femoral Replacement System for Acute Periprosthetic Fracture with Catastrophic Implant Failure: A Case Report

CASE

A 54-year-old man with arthrogryposis and 7 failed revision knee arthroplasties presented with acute periprosthetic fracture and catastrophic failure of a modular-hinged implant at the stem-condylar junction. To prevent total femoral replacement, above-knee amputation, or fusion, a custom distal femoral replacement was offered. The implant was procured during the emergency hospitalization and cemented with the proximal stem engaging the distal ipsilateral total hip arthroplasty, creating endofemoral implant continuity. The patient returned to nonassisted ambulation with stable implant fixation at the 1-year follow-up.

CONCLUSION

Custom distal femoral replacing implants are feasible for complex emergency knee-salvage revisions with poor bone stock to avert more radical reconstruction alternatives.

Routine Radiographs After Total Joint Arthroplasty: Is There Clinical Value?

BACKGROUND

Routine radiographs have historically been obtained during routine care after total joint arthroplasty (TJA). However, substantial improvements in surgical technique, biomaterials, and changes in payment models placing greater emphasis on value have occurred. Recently, there has been interest in a transition to performing follow-up visits virtually. The purpose of this study was to assess how frequently patients attend postoperative appointments and the clinical utility of routine radiographs after TJA.

METHODS

Patients undergoing primary total hip arthroplasty and total knee arthroplasty at a single tertiary institution in 2018 were included. Patients attending scheduled follow-up at 6 to 12 weeks and 1 year were assessed. Retrospective chart review was conducted to determine whether abnormalities were noted on routine radiographic surveillance by the orthopedic surgeons or radiologist and if any radiographic findings altered clinical management.

RESULTS

A total of 938 TJAs were performed, and 885 met inclusion criteria, with 423 (47.8%) total hip arthroplasties and 462 (52.2%) total knee arthroplasties. Eight hundred sixty-five (97.7%) patients attended a follow-up visit at 6 or 12 weeks and 589 (66.6%) attended at 1 year postoperatively. A single radiographic abnormality was detected, occurring at the 6- to 12-week period by the radiologist and interpreted as being an artifact by the surgeon. No additional radiographic abnormalities were detected at 1 year. Information from radiographs did not change clinical management for any patients.

CONCLUSION

In a large cohort of patients, routine radiographic surveillance did not detect any true abnormalities during the first year after primary TJA. For patients without symptoms attributable to the TJA prosthesis, conducting virtual care visits without routine radiographs may be considered.