Trends in obesity prevalence among total hip arthroplasty patients and the effect on surgical outcomes, 2008-2016

Trends in prevalence and complications for smokers who underwent total hip arthroplasty from 2011 to 2019: an analysis of 243,163 patients

BACKGROUND

Smoking is an established risk factor for postoperative complications after total hip arthroplasty (THA). It is unknown if the decreasing prevalence of adult smoking in the United States is reflected in the elective THA patient population. We aimed to investigate recent trends in: (1) the prevalence of smoking pre-THA, stratified by patient demographics; and (2) rates of 30-day complications and increased healthcare utilisation post-THA in smokers versus non-smokers.

METHODS

Patients who underwent primary elective THA (2011-2019) were identified using the National Surgical Quality Improvement Program database. A total of 243,163 cases (Smokers: n = 30,536; Non-smokers: n = 212,627) were included. Trends analyses were performed for smoking prevalence across the study period. Smokers were propensity score-matched (1:1) to a cohort of non-smokers (n = 29,628, each), and rates of 30-day complications, readmission, and non-home discharge were compared.

RESULTS

The rate of preoperative smoking significantly decreased from 14.0% in 2011 to 11.6% in 2019 (p-trend = 0.0286). When stratified, a significant decreasing trend in smoking was found for males and all races; within races, American-Indian/Alaska-Native race had the sharpest decline (2011:36.3% vs. 2019:23.2%). No significant change in 30-day complication rates among smokers or non-smokers was observed (p-trend > 0.05), but non-home discharge significantly decreased for both smokers (p-trend = 0.001) and non-smokers (p-trend < 0.001). After matching, higher rates of superficial surgical site infections (SSI) (0.9% vs. 0.5%; p < 0.001), deep SSI (0.5% vs. 0.3%; p < 0.001), wound disruption (0.2% vs. 0.1%; p = 0.006), and readmission (4.2% vs. 3.1%; p = <0.001) were found in smokers versus non-smokers.

CONCLUSIONS

The present study is encouraging that national efforts to reduce the prevalence of smoking may be successful within the THA population, but there is a persistently elevated risk of postoperative complications in smokers after THA.

Is Preoperative Weight Reduction in Patients Who Have Body Mass Index ≥ 40 Associated With Lower Complication Rates After Primary Total Hip Arthroplasty?

BACKGROUND

Given the heightened risk of postoperative complications associated with obesity, delaying total hip arthroplasty (THA) in patients who have a body mass index (BMI) > 40 to maximize preoperative weight loss has been advocated by professional societies and orthopaedic surgeons. While the benefits of this strategy are not well-understood, previous studies have suggested that a 5% reduction in weight or BMI may be associated with reduced complications after THA.

METHODS

We identified 613 patients who underwent primary THA in a single institution during a 7-year period and who had a BMI >40 recorded from 9 to 12 months prior to surgery. Subjects were stratified into 3 cohorts based on whether their baseline BMI decreased by >5% (147 patients, 24%), was unchanged ( ± 5%) (336 patients, 55%), or increased by >5% (130 patients, 21%) on the day of surgery. The frequency of 90-days Hip Society and Centers for Medicare & Medicaid Services complications was compared between these cohorts. There were significant baseline differences between the cohorts with respect to baseline American Society of Anesthesiologists class (P < .001) and hemoglobin A1C (P = .011), which were accounted for in a multivariate regression analysis.

RESULTS

In univariate analysis, there was a lower incidence of readmission (P = .025) and total complications (P = .005) in the increased BMI cohort. The overall complication rate was 18.4% in the decreased BMI cohort, 17.6% in the unchanged cohort, and 6.2% in the increased cohort. However, multivariable regression analysis controlling for potential confounders did not find that preoperative change in BMI was associated with differences in 90-days complications between cohorts (P > .05).

CONCLUSIONS

Patients who have a BMI >40 and achieved a clinically significant (>5%) BMI reduction prior to THA did not have a lower risk of 90-days complications or readmissions. Thus, delaying THA in these patients to encourage weight loss may result in restricting access to a beneficial surgery without an appreciable safety benefit.

Patient satisfaction and patient-reported outcomes do not vary by BMI class in total hip arthroplasty

PURPOSE

Obesity has been identified as a risk factor for postoperative complications in patients undergoing total hip arthroplasty (THA). This study aimed to investigate patient-reported outcomes, pain, and satisfaction as a function of body mass index (BMI) class in patients undergoing THA.

METHODS

1736 patients within a prospective observational study were categorized into BMI classes. Pre- and postoperative Hip disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS JR), satisfaction, and pain scores were compared by BMI class using one-way ANOVA.

RESULTS

Healthy weight patients reported the highest preoperative HOOS JR (56.66 ± 13.35) compared to 45.51 ± 14.45 in Class III subjects. Healthy weight and Class III patients reported the lowest (5.65 ± 2.01) and highest (7.06 ± 1.98, p < 0.0001) preoperative pain, respectively. Changes in HOOS JR scores from baseline suggest larger improvements with increasing BMI class, where Class III patients reported an increase of 33.7 ± 15.6 points at 90 days compared to 26.1 ± 17.1 in healthy weight individuals (p = 0.002). Fewer healthy weight patients achieved the minimal clinically important difference (87.4%) for HOOS JR compared to Class II (96.5%) and III (94.7%) obesity groups at 90 days postoperatively. Changes in satisfaction and pain scores were largest in the Class III patients. Overall, no functional outcomes varied by BMI class postoperatively.

CONCLUSION

Patients of higher BMI class reported greater improvements following THA. While risk/benefit shared decision-making remains a personalized requirement of THA, this study highlights that utilization of BMI cutoff may not be warranted based on pain and functional improvement.

Effect of body mass index on acute postoperative complications following Total Ankle Arthroplasty (TAA)

BACKGROUND

Total ankle arthroplasty (TAA) is an effective treatment for various ankle pathologies, but some concern remains for the high associated complication and failure rates relative to major joint arthroplasty of the hip and knee. Patient body mass index (BMI) is a modifiable and potentially important preoperative variable when evaluating postoperative complications. The purpose of this study is to evaluate the effect of BMI, age and sex on the acute postoperative complication rate after TAA.

METHODS

We retrospectively reviewed adult patients who underwent TAA between 2006 and 2021 from the NSQIP database. Using overweight patients as the reference BMI group, we utilized log-binomial models to estimate risk ratios on outcomes while adjusting for sex and age to investigate whether there were significant adjusted differences in complication rates among the BMI groups.

RESULTS

We found that, relative to overweight patients, there were no statistically significant differences in the risk of acute complications for underweight (BMI < 18.5) (P = .118), healthy weight (18.5≤BMI < 25) (P = .544), obese (30≤BMI < 40) (P = .930), or morbidly obese (BMI < 40) (P = .602) patients who underwent TAA. There were also no statistically significant differences in the risk of acute complications based on age category (P = .482,.824) or sex (P = .440) for TAA. Additionally, there were no significant differences between the BMI groups for either major complications (P = .980) or minor complications (P = .168).

CONCLUSION

Ultimately, we found that BMI, age, and sex did not lead to statistically significant differences in the risk of complications within 30 days postoperatively for TAA, even when stratified by major vs minor complications.

LEVEL OF EVIDENCE

Level III.

Body Mass Index Does Not Drive the Risk for Early Postoperative Instability After Total Hip Arthroplasty: A Matched Cohort Analysis

BACKGROUND

Instability remains the leading cause of revision following total hip arthroplasty (THA). The objective of the present investigation was to determine whether an elevated body mass index (BMI) is associated with an increased risk of instability after primary THA.

METHODS

An administrative claims database was queried for patients undergoing elective, primary THA for osteoarthritis between 2010 and 2022. Patients who underwent THA for a femoral neck fracture were excluded. Patients who had an elevated BMI were grouped into the following cohorts: 25 to 29.9 (n = 2,313), 30 to 34.9 (n = 2,230), 35 to 39.9 (n = 1,852), 40 to 44.9 (n = 1,450), 45 to 49.9 (n = 752), and 50 to 59.9 (n = 334). Patients were matched 1:1 based on age, sex, and Elixhauser Comorbidity Index, as well as a history of spinal fusion, neurodegenerative disorders, and alcohol abuse, to controls with a normal BMI (20 to 24.9). A multivariate logistic regression controlling for age, sex, Elixhauser Comorbidity Index, and additional risk factors for dislocation was used to evaluate dislocation rates at 30 days, 90 days, 6 months, 1 year, and 2 years. Rates of revision for instability were similarly compared at 1 year and 2 years postoperatively.

RESULTS

No significant differences in dislocation rate were observed between control patients and each of the evaluated BMI classes at all evaluated postoperative intervals (all P values > .05). Similarly, the risk of revision for instability was comparable between the normal weight cohort and each evaluated BMI class at 1 year and 2 years postoperatively (all P values > .05).

CONCLUSIONS

Controlling for comorbidities and known risk factors for instability, the present analysis demonstrated no difference in rates of dislocation or revision for instability between normal-weight patients and those in higher BMI classes.

Semaglutide Use Prior to Total Hip Arthroplasty Results in Fewer Postoperative Prosthetic Joint Infections and Readmissions

BACKGROUND

Semaglutide, a novel diabetes management medication, is known for its efficacy in inducing weight loss. Despite this, its impact on outcomes after total hip arthroplasty (THA) remains unclear. The aim of this study was to evaluate if THA patients on semaglutide demonstrate: (1) fewer medical complications; (2) fewer implant-related complications; (3) fewer readmissions; and (4) lower costs.

METHODS

Using a national claims database from 2010 to 2021, we retrospectively examined diabetic patients prescribed semaglutide who underwent primary THA. This yielded 9,465 patients (Semaglutide = 1,653; Control = 7,812). Multivariable logistic regression was used to evaluate the following outcomes: 90-day postoperative medical complications, 2-year implant-related complications, 90-day readmissions, in-hospital lengths of stay, and day-of-surgery and 90-day episode of care costs.

RESULTS

Semaglutide users exhibited lower 90-day readmission rates (6.2 versus 8.8%; odds ratio 0.68; P < .01) and reduced prosthetic joint infections (1.6 versus 2.9%; odds ratio 0.56; P < .01). However, medical complication rates, hospital stays, same-day surgical costs, and 90-day episode costs showed no significant differences.

CONCLUSIONS

This study highlights semaglutide users undergoing THA with fewer 90-day readmissions and 2-year prosthetic joint infections. Although no variance appeared in medical complications, hospital stays, or costs, the medication's notable glycemic control and weight loss benefits could prompt pre-surgery consideration. Further research is essential for a comprehensive understanding of semaglutide's impact on post-THA outcomes.

Does Your Patient Need to Lose Weight? Weight Change Before and After Total Hip Arthroplasty Does Not Affect Health Care Utilization and Achievement of the Minimal Clinically Important Difference

BACKGROUND

Despite the potential negative impact of preoperative obesity on total hip arthroplasty (THA) outcomes, the association between preoperative and postoperative weight change and outcomes is much less understood. Therefore, this study aimed to determine the impact of preoperative and postoperative weight change and preoperative body mass index (BMI) on health care utilization, satisfaction, and achievement of minimal clinically important difference (MCID) for Hip Disability and Osteoarthritis Outcome Score Physical Function Short-Form (HOOS PS) and HOOS Pain.

METHODS

Patients who underwent primary elective unilateral THA between January 2016 and December 2019 were included (N = 2,868). Multivariable logistic regression assessed the association between BMI and preoperative and postoperative weight change on outcomes while controlling for demographic characteristics.

RESULTS

There was no association between preoperative weight change and prolonged length of stay (> 3 days), 90-day readmission, nonhome discharge, patient dissatisfaction at 1 year, or achievement of HOOS Pain or HOOS PS MCID. Postoperative weight loss was an independent risk factor for patient dissatisfaction at 1 year but was not associated with achievement of either HOOS Pain or HOOS PS MCID at 1-year postoperative. Preoperative obesity classes I to III were independent risk factors for nonhome discharge. Nevertheless, preoperative obesity class I and class II were associated with an increased probability of reaching HOOS Pain MCID. Preoperative BMI was not associated with an increased risk of patient dissatisfaction.

CONCLUSIONS

Preoperative weight change does not appear to influence health care utilization, satisfaction, or achievement of MCID in pain and function following THA. Postoperative weight loss may play a role as a risk factor for dissatisfaction following THA. Additionally, patients who had a higher baseline BMI may be more likely to see improvement in pain following THA. Therefore, when counseling obese patients for THA, surgeons must balance the risk of perioperative complications with the expectation of greater improvements in pain.

A quasi-experimental study of group counselling effectiveness for patient functional ability and quality of counselling among patients with hip arthroplasty

AIM

The aim of this study was to investigate effectiveness of group counselling for the patients with hip arthroplasty, self-assessed functional ability, and quality of counselling.

DESIGN

A quasi-experimental study.

METHOD

The questionnaire included the Counselling Quality Instrument (CQI), Harris hip score and Oldwellactive self-rated wellness profile. A Mann-Whitney U- and chi-squared and t-tests were used. A Wilcoxon singed rank test were used to evaluate changes in functional ability.

NO PATIENT OR PUBLIC CONTRIBUTION

Patients and the public were not involved in the design, recruitment and implementation of this study.

RESULTS

Fifty patients participated. Patients reported better results for limping (p = 0.000), walking distance (p = 0.000) and use of a walking aid (p = 0.001) in the follow-up time point and they pain decreased. Patients were satisfied with interactions during counselling; gender (p = 0.000) and use of a walking aid (p = 0.044) were found to significantly affect. A lack of goal-oriented counselling was in depressive symptoms (p = 0.016), worries (p = 0.010) and loneliness (p = 0.026).

Did the dislocation risk after primary total hip arthroplasty decrease over time? A meta-analysis across six decades

BACKGROUND

While continuous optimization is attempted to decrease the incidence of dislocation after total hip arthroplasty (THA), dislocation remains a major complication. This meta-analysis aims to analyze the evolution of the dislocation risk after primary THA over the decades and to evaluate its potential publication bias.

PATIENTS AND METHODS

A systematic search was performed according to the PRISMA guidelines for this meta-analysis in the literature published between 1962 and 2020. MEDLINE, Cochrane and Embase databases were searched for studies reporting the dislocation risk and length of follow-up. Studies that reported on revision rates only and did not mention separate dislocations were excluded. All study designs were eligible. Study quality was assessed by existing quality assessment tools adjusted for arthroplasty research. Overall risk and yearly dislocation rates were calculated and related to historical time frame, study design, sample size and length of follow-up.

RESULTS

In total, 174 studies were included with an overall moderate quality. In total there were 85.209 dislocations reported in 5.030.293 THAs, showing an overall dislocation risk of 1.7%, with a median follow-up of 24 months. The overall dislocation risk classified per decade decreased from 3.7% in 1960-1970 to 0.7% in 2010-2020. The yearly dislocation rate decreased from 1.8 to 0.7% within these same decades. There was no significant correlation between the reported dislocation risk and the duration of follow-up (p = 0.903) or sample size (p = 0.755). The reported dislocation risk was higher in articles with registry data compared to other study designs (p = 0.021).

CONCLUSION

The dislocation risk in THA has been decreasing over the past decades to 0.7%. Non-selective registry studies reported a higher dislocation risk compared to studies with selective cohorts and RCTs. This indicates that the actual dislocation risk is higher than often reported and 'real-world data' are reflected better in large-scale cohorts and registries.

Outcomes of morbidly obese patients undergoing total hip arthroplasty with the anterior-based muscle-sparing approach

Obesity is associated with an increased risk of hip osteoarthritis, resulting in an increased number of total hip arthroplasties (THAs) performed annually. This study examines the peri- and postoperative outcomes of morbidly obese (MO) patients (BMI ≥ 40 kg/m²) compared to healthy weight (HW) patients (BMI 18.5 to < 25 kg/m²) who underwent a THA using the anterior-based muscle-sparing (ABMS) approach. This retrospective cohort study observes peri- and postoperative outcomes of MO and HW patients who underwent a primary, unilateral THA with the ABMS approach. Data from surgeries performed by three surgeons at a single institution was collected from January 2013 to August 2020 and analyzed using Microsoft Excel and Stata 17.0. This study compares 341 MO to 1,140 HW patients. Anaesthesia, surgery duration, and length of hospital stay was significantly lower in HW patients compared to MO. There was no difference in incidence of pulmonary embolism, periprosthetic fracture, or dislocation between the two groups. The rate of infection in MO patients (1.47%) was significantly higher than HW patients (0.14%). Preoperative patient-reported outcome measures (PROMs) show a significantly higher pain level in MO patients and a significantly lower score in functional abilities. Overall, six-week and one-year postoperative data show higher levels of pain, lower levels of functional improvement, and lower satisfaction scores in the MO group. The comorbidities of obesity are well studied; however, the implications of THA using the ABMS approach have not been studied. Our peri- and postoperative results demonstrate significant improvements in PROMs in MO patients undergoing THA. However, the incidence of deep infection was significantly higher in this group compared with HW patients.

Trends of obesity rates between primary total hip arthroplasty patients and the general population from 2013 to 2020

Background

The prevalence of obesity in total hip arthroplasty (THA) patients has been studied in the past. However, there has not been direct comparison against obesity in the general population. This study compared yearly trends in BMI and obesity rates between patients who had undergone primary THA and those from the general patient population.

Methods

We retrospectively reviewed all patients over the age of 18 who underwent primary, elective THA and those who had an annual routine physical exam between January 2013 and December 2020 at our academic tertiary medical center. Baseline demographics were controlled in our statistical models. Significance of yearly trends was determined through a linear regression analysis. Independent samples t-test and Chi-square test were used to compare means and proportions between the two groups, respectively.

Results

A total of 11,250 primary THA patients and 1,039,918 annual physical exam patients were included. Average BMI for the THA group was significantly higher (P < 0.001) each year compared to the annual physicals group (APG). Higher obesity rates were observed in all obesity subgroups (all classes, and class I–III individually) for THA patients each year compared to the APG. Interestingly, while we found a significantly increasing trend in obesity for the general population (P < 0.001), BMI and obesity rates remained stable in the THA population.

Conclusion

While our general patient population showed significant increase in BMI and obesity over time, THA patients had higher, yet stable, BMI. Further investigation is required to determine the role of risk optimization in these findings.

Level III Evidence

Retrospective Cohort Study.

Soft-tissue thickness radiographic measurement: a marker to evaluate acute periprosthetic joint infection risk in total hip replacement

The objective of our study was to evaluate the association between acute periprosthetic joint infection (APJI) and radiographic measurement of soft-tissue thickness in elective total hip replacement surgery. A case-control study was conducted to compare the soft-tissue thickness radiographic measurement (SRM) at the hip in patients diagnosed with APJI based on Tsukayama et al. (2003) criteria after total hip replacement with patients that were not infected, at a single institution from 2013 to 2019. To minimize selection bias, each case was matched with two controls using the following methodology: patients of the same sex, with an age variation of ± 5 years, and nearest in surgery date to the cases were selected. All postoperative radiographs were performed in the first 24 h after total hip arthroplasty (THA) surgery as it is protocolized in our institution. Soft-tissue thickness radiographic measurement was defined as the distance from the tip of the greater trochanter to the skin following a perpendicular line to the femoral diaphysis in postoperative anteroposterior hip radiographs. In total, 78 patients were included (26 cases and 52 controls). The SRM median of the cases was 76.19 mm (SD: 26.518) and 53.5 mm (SD: 20.47) in controls. A multivariate logistic regression model showed an independent association between APJI and SRM (odds ratio (OR) = 1.033, 95 % confidence interval (CI) 1.007–1.059, p=0.012). Patients with an SRM greater than 60 mm had a 7-fold increase in the odds of APJI (OR = 7.295, 95 % CI = 2.364–22.511, p<0.001). The results of our study suggest an association between large SRM at the hip and the risk of APJI in patients with primary total hip arthroplasty. SRM may be a helpful and easy tool for evaluating the risk of APJI before elective primary total hip replacement surgery.

Obesity in Total Hip Arthroplasty: Demographic Disparities and Outcome Incongruities

Introduction

As morbid obesity disproportionately affects minorities and those of lower socioeconomic status, body mass index (BMI) restrictions on total hip arthroplasty (THA) may harm populations already facing disparities in care. Therefore, this study analyzed demographics and outcomes in morbidly obese primary THA patients.

Methods

The National Inpatient Sample was queried for THAs performed between 2009 and 2016. Of 2,676,086 patients identified, 453,250 had a BMI over 25 kg/m². Patients were stratified by BMI into overweight (BMI=25.0-29.9 kg/m²), non-morbidly obese (BMI=30.0-40.0 kg/m²), and morbidly obese (BMI>40.1 kg/m²). Patient demographics (age, sex, race, insurance, income, and Charlson Comorbidity Index) and outcomes (length of stay [LOS], mortality, disposition, complications, charges, and costs) were assessed. Categorical and continuous data were analyzed with chi-square analyses and one-way analyses of variance, respectively.

Results

The number of overweight, non-morbidly obese, and morbidly obese patients increased by 299.0%, 109.3%, and 90.9%, respectively, between 2009 and 2016 (p<0.001). Morbidly obese patients were younger than non-morbidly obese and overweight patients (p<0.001) and had a higher proportion of females (p<0.001) and black patients (p<0.001). Morbidly obese patients most frequently used Medicaid and private insurance (p<0.001). Morbidly obese patients demonstrated a longer LOS, a higher mortality rate, a lower rate of home discharges and the most complications (all, p<0.001). 

Conclusion

These results reflect the worsening obesity epidemic and may be useful in counseling preoperative weight loss to morbidly obese patients to reduce mortality and complications.