Preoperative risk stratification minimizes 90-day complications in morbidly obese patients undergoing primary total knee arthroplasty

Outcomes of Obese Patients Undergoing Primary Total Knee Arthroplasty: Trends Over 30 Years

BACKGROUND

The rates of obesity among patients undergoing total knee arthroplasty (TKA) have substantially increased. In addition, obesity is a well-established risk factor for complications after TKA. The purpose of this study was to analyze trends in body mass index (BMI) and complication risk among obese patients undergoing primary TKA treated at a single institution over 3 decades.

METHODS

Utilizing an institutional total joint registry, 13,919 primary TKAs performed to treat osteoarthritis between 1990 and 2019 were identified. Patients were stratified by BMI according to the World Health Organization (WHO) classification into 3 groups: non-obese (BMI, <30 kg/m 2 ), WHO Class-I and II obese (BMI, 30 to 39.9 kg/m 2 ), and WHO Class-III obese (BMI, ≥40 kg/m 2 ). Trends in BMI and survivorship free from reoperation, revision, and periprosthetic joint infection (PJI) were analyzed over time while controlling for age, sex, and the Charlson Comorbidity Index.

RESULTS

Over the study period, there was a 90% increase in the prevalence of Class-II obesity (13% to 25%) and a 300% increase in Class-III obesity (3% to 12%). Analysis of the entire cohort demonstrated a decrease in the 2-year risk of any reoperation, any revision, and PJI (p < 0.05 for all) with time. The risk decreased significantly over time for non-obese patients for any reoperation (p = 0.029) and any revision (p = 0.004) and for Class-III obese patients for any reoperation (p = 0.038) and any revision (p = 0.012), but it remained stable for Class-I and II obese patients. The risk of PJI decreased from 1990 to 2019 for non-obese patients (p = 0.005), but there were no significant changes in PJI risk for any obesity group.

CONCLUSIONS

Despite increasing rates of obesity among our patients who underwent TKA, we observed decreasing risks of reoperation, revision, and PJI over time. The risks of reoperation and revision declined among non-obese patients, remained stable for Class-I and II obese patients, and declined for Class-III obese patients. The PJI risk declined for non-obese patients over the study period, but no such decline occurred for any category of obesity. Despite the decreasing risks of reoperation and revision, further work is needed to improve PJI risk in obese patients.

LEVEL OF EVIDENCE

Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

The Investigation of Preoperative Factors Associated With Postoperative Outcomes Following Total Knee Arthroplasty for Osteoarthritis: A Scoping Review

This study aimed to investigate preoperative factors associated with non-home discharges from acute care hospitals in patients undergoing total knee arthroplasty (TKA) due to osteoarthritis. It was a scoping review focused on patients who received their first unilateral TKA for osteoarthritis. The research targeted observational studies that examined the destinations of patients post-surgery based on preoperative factors, with a literature search conducted in April 2023. Out of 3,255 identified papers, 28 met the eligibility criteria. A total of 26 preoperative factors were identified as potentially related to discharge destinations, including age, gender, comorbidities, and obesity. By selecting an appropriate discharge destination based on preoperative factors, there may be potential for more efficient use of medical resources. Future studies should consider preoperative factors in the context of national healthcare systems and lengths of hospital stay.

Orthopaedic Nurse Navigators and Total Joint Arthroplasty Preoperative Optimization: Obesity and Malnutrition-Part Four of the Movement Is Life Special ONJ Series

Obesity and malnutrition affect many patients with osteoarthritis and can predispose patients to worse outcomes after total joint arthroplasty (TJA). However, these modifiable risk factors can be addressed in preoperative optimization programs driven by nurse navigators. Our aim is to provide resources and recommendations for nurse navigators when addressing obesity and malnutrition among TJA patients. In addition to discussions with nurse navigators regarding obesity and malnutrition, a literature review was conducted to assess the current practice standards for management. Nurse navigators often had difficulty implementing long-term interventions, but interventions in the literature included medical and bariatric treatments for obesity and more targeted assessment of nutrition status. These findings are incorporated into our recommendations for nurse navigators. Addressing obesity and malnutrition in preoperative optimization can contribute to improved outcomes, as has been demonstrated in current practice and in the literature.

The Impact of Metabolic Syndrome and Obesity on Perioperative Total Joint Arthroplasty Outcomes: The Obesity Paradox and Risk Assessment in Total Joint Arthroplasty

Background

The relationship between elevated body mass index (BMI) and adverse outcomes in joint arthroplasty is well established in the literature. This paper aims to challenge the conventional thought of excluding patients from a total knee or hip replacement based on BMI alone. Instead, we propose using the metabolic syndrome (MetS) and its defining components to better identify patients at high risk for intraoperative and postoperative complications.

Methods

Patients who underwent primary, elective total knee and total hip arthroplasty were identified in the 2015-2020 American College of Surgeons National Surgical Quality Improvement Program database. Several defining components of MetS, such as hypertension, diabetes, and obesity, were compared to a metabolically healthy cohort. Postoperative outcomes assessed included mortality, length of hospital stay, 30-day surgical and medical complications, and discharge.

Results

The outcomes of 529,737 patients from the American College of Surgeons National Surgical Quality Improvement Program who underwent total knee and total hip arthroplasty were assessed. MetS is associated with increased complications and increased mortality. Both hypertension and diabetes are associated with increased complications but have no impact on mortality. Interestingly, while obesity was associated with increased complications, there was a significant decrease in mortality.

Conclusions

Our results show that the impact of MetS is more than the sum of its constitutive parts. Additionally, obese patients experience a protective effect, with lower mortality than their nonobese counterparts. This study supports moving away from strict BMI cutoffs alone for someone to be eligible for an arthroplasty surgery and offers more granular data for risk stratification and patient selection.

Does Value-Based Care Threaten Joint Arthroplasty Access for Vulnerable Patient Populations?: AOA Critical Issues

Health-care expenses have been projected to increase from 17.7% of the U.S. gross domestic product (GDP) in 2014 to 19.6% in 2024. The unsustainable increase in health-care costs has contributed toward support for value-based health care (VBHC) reform. Contemporary VBHC reform programs relevant to orthopaedic surgery include the voluntary Bundled Payments for Care Improvement initiatives (BPCI and BPCI-Advanced) and the Comprehensive Care for Joint Replacement (CJR) program, a mandatory bundled payment program.The purported benefits of transitioning from volume-based reimbursement to value-based reimbursement include moving from a fragmented provider-centered care model to a patient-centered model, with greater care coordination and alignment among providers focused on improving value. VBHC models allow innovative strategies to proactively invest resources to promote value (e.g., the use of nurse navigators) while eliminating unnecessary resources that do not promote value. However, major concerns regarding VBHC include the absence of medical and socioeconomic risk stratification as well as decreased access for higher-risk patients.This article identifies the benefits and potential unintended consequences of VBHC reform, with a focus on joint arthroplasty. We also discuss some potential strategies to promote innovation and improve value without compromising access for vulnerable patients.

Projected Prevalence of Obesity in Primary Total Knee Arthroplasty: How Big Will the Problem Get?

BACKGROUND

Obesity is a well-established risk factor for complications following primary total knee arthroplasty (TKA). The purpose of this study is to utilize 3 national databases to develop projections of obesity within the general population and primary TKA patients in the United States through 2029.

METHODS

Data from the National Surgical Quality Improvement Program (NSQIP), the Behavior Risk Factor Surveillance System (BRFSS), and the National Health and Nutrition Examination Survey were queried for years 1999-2019. Current Procedural Terminology code 27447 was used to identify primary TKA patients in NSQIP. Individuals were categorized according to body mass index (kg/m²) by year: normal weight (≤24.9); overweight (25.0-29.9); obese (30.0-39.9); and morbidly obese (≥40). Multinomial logistic regression was used to project categorical body mass index data for years 2020-2029.

RESULTS

A total of 8,372,221 individuals were included (7,986,414 BRFSS, 385,807 NSQIP TKA). From 2011 to 2019, the prevalence of normal weight and overweight individuals declined in the general population (BRFSS) and in primary TKA. Prevalence of obese/morbidly obese individuals increased in the general population from 31% to 36% and in primary TKA from 60% to 64%. Projection models estimate that by 2029, 46% of the general population will be obese/morbidly obese and 69% of primary TKA will be obese/morbidly obese.

CONCLUSION

By 2029, we estimate ≥69% of primary TKA to be obese/morbidly obese. Increased resources dedicated to care pathways and research focused on improving outcomes in obese arthroplasty patients will be necessary as this population continues to grow.

LEVEL OF EVIDENCE

Level III, Retrospective Cohort Study.

Projected Prevalence of Obesity in Primary Total Hip Arthroplasty: How Big Will the Problem Get?

BACKGROUND

Obesity is associated with higher rates of adverse outcomes following primary total hip arthroplasty (THA). The purpose of this study is to utilize 3 national databases to develop projections of obesity within the general population and primary THA patients in the United States through 2029.

METHODS

Data from the National Surgical Quality Improvement Program (NSQIP), the Behavior Risk Factor Surveillance System (BRFSS), and the National Health and Nutrition Examination Survey were queried for years 1999-2019. Current Procedural Terminology code 27130 was used to identify primary THA patients in NSQIP. Individuals were categorized according to body mass index (kg/m²) by year: normal weight (≤24.9); overweight (25.0-29.9); obese (30.0-39.9); and morbidly obese (≥40). Multinomial logistic regression was used to project categorical body mass index data for years 2020-2029.

RESULTS

A total of 8,222,013 individuals were included (7,986,414 BRFSS, 235,599 NSQIP THA). From 2011 to 2019, the prevalence of normal weight and overweight individuals declined in the general population (BRFSS) and in primary THA. Prevalence of obese/morbidly obese individuals increased in the general population from 31% to 36% and in primary THA from 42% to 49%. Projection models estimate that by 2029, 46% of the general population will be obese/morbidly obese and 55% of primary THA will be obese/morbidly obese.

CONCLUSION

By 2029, we estimate ≥55% of primary THA to be obese/morbidly obese. Increased resources dedicated to care pathways and research focused on improving outcomes in obese arthroplasty patients will be necessary as this population continues to grow.

LEVEL OF EVIDENCE

Level III, Retrospective Cohort Study.