Obesity and Reverse Total Shoulder Arthroplasty

The role of body mass index in survivorship and clinical outcomes in total shoulder arthroplasty

BACKGROUND

Increased body mass index (BMI) is a potential risk factor for poorer outcomes and complications. However, the influence of BMI on the long-term outcomes of anatomic total shoulder arthroplasty (aTSA) and reverse total shoulder arthroplasty (rTSA) remains to be fully elucidated.

METHODS

Institutional records were queried to identify patients who underwent primary total shoulder arthroplasty (TSA) between 2009 and 2020 with a minimum of 2 years of clinical follow-up. Retrospective review was performed to collect demographic characteristics; comorbidity status; and range-of-motion and strength measurements in forward elevation, external rotation, and internal rotation. Patients were contacted by telephone to provide patient-reported outcomes (PROs). Patients were stratified into 3 cohorts by BMI: underweight or normal weight (U/NW, BMI ≤25 kg/m2), overweight (OW, BMI >25 to ≤30 kg/m2), and obese (BMI >30 kg/m2).

RESULTS

Among 466 TSA patients, 245 underwent aTSA whereas 221 underwent rTSA. In the aTSA cohort, 40 patients were classified as U/NW; 72, as OW; and 133, as obese. Comparatively, the rTSA cohort was composed of 33 U/NW, 79 OW, and 209 obese patients. Patients in the aTSA and rTSA cohorts had an average follow-up period of 5.8 ± 3.2 years and 4.5 ± 2.3 years, respectively. No differences in age at surgery were found in the aTSA group (U/NW vs. obese, 65.2 ± 7.9 years vs. 61.9 ± 8.9 years; P = .133); however, in the rTSA cohort, BMI was found to be inversely related to age at surgery (U/NW vs. obese, 72.4 ± 8.8 years vs. 65.7 ± 8.3 years; P < .001). Across all BMI cohorts, patients saw great improvements in range of motion and strength. Postoperative PROs after TSA did not vary by BMI in terms of Single Assessment Numeric Evaluation, Simple Shoulder Test, visual analog scale pain, and American Shoulder and Elbow Surgeons scores. There was no significant difference in survival rates at 10-year follow-up in the aTSA cohort (U/NW vs. obese, 95.8% vs. 93.2%; P = .753) or rTSA cohort (U/NW vs. obese, 94.7% vs. 94.5%; P = .791).

CONCLUSION

With dramatic improvements in range of motion, minimal differences in PROs, and high rates of implant survival, TSA is a safe and effective treatment option for all patients, including overweight and obese patients.

Mitigating the Risk of Instability After Reverse Shoulder Arthroplasty: A Critical Analysis Review of Patient and Surgical Factors

» Instability and dislocation after reverse shoulder arthroplasty may occur in up to 31% of patients.

» Clinical risk factors for instability include younger age, male sex, increased body mass index, preoperative diagnosis of proximal humerus fracture or rotator cuff pathology, history of instability of the native shoulder or after surgery, and a medical history of Parkinson's disease.

» Patients with rheumatoid arthritis and decreased proximity to the coracoid may also be at greater risk.

» In patients at a high risk of instability, surgeons should consider a more lateralized prosthesis (particularly in patients with an incompetent rotator cuff), repairing the subscapularis (particularly when using a medialized prosthesis), and upsizing the glenosphere (>40 mm in male and 38-40 mm in female patients).

» While potentially useful, less evidence exists for the use of a constrained liner (particularly with a lateralized glenosphere and/or in low-demand patients) and rotating the polyethylene liner posteriorly to avoid impingement.

Association between radiographic soft-tissue thickness and increased length of stay, operative time, and infection rate after reverse shoulder arthroplasty

BACKGROUND

Reverse shoulder arthroplasty (RSA) is a widely performed surgical procedure to address various shoulder pathologies. Several studies have suggested that radiographic soft-tissue thickness may play a role in predicting complications after orthopedic surgery, but there have been limited studies determining the use of radiographic soft-tissue thickness in RSA. The purpose of this study was to evaluate whether radiographic soft-tissue thickness could predict clinical outcomes after RSA and compare the predictive capabilities against body mass index (BMI). We hypothesized that increased radiographic shoulder soft-tissue thickness would be a strong predictor of operative time, length of stay (LOS), and infection in elective RSA.

MATERIAL AND METHODS

A retrospective review of patients undergoing RSA at an academic institution was conducted. Preoperative radiographic images were evaluated including measurements of the radius from the humeral head center to the skin (HS), deltoid radius-to-humeral head radius ratio (DHR), deltoid size, and subcutaneous tissue size. Different correlation coefficients were used to analyze various types of relationships, and the strength of these associations was classified based on predefined boundaries. Subsequently, multivariable linear and logistic regressions were performed to determine whether HS, DHR, deltoid size, and subcutaneous tissue size could predict LOS, operative time, or infection while controlling for patient factors.

RESULTS

HS was the most influential factor in predicting both operative time and LOS after RSA, with strong associations indicated by standardized β coefficients of 0.234 for operative time and 0.432 for LOS. Subcutaneous tissue size, deltoid size, and DHR also showed stronger predictive values than BMI for both outcomes. In terms of prosthetic joint infection, HS, deltoid size, and DHR were significant predictors, with HS demonstrating the highest predictive power (Nagelkerke R2 = 0.44), whereas BMI did not show a statistically significant association with infection. Low event counts resulted in wide confidence intervals for odds ratios in the infection analysis.

CONCLUSION

Greater shoulder soft-tissue thickness as measured with concentric circles on radiographs is a strong predictor of operative time, LOS, and postoperative infection in elective primary RSA patients.

Components of metabolic syndrome as significant risk factors for postoperative complications following total shoulder arthroplasty: hypertension, diabetes, and obesity

Background

Metabolic syndrome (MetS) is a known risk factor for adverse postoperative outcomes. However, the literature surrounding the effects of MetS on orthopedic surgery outcomes following total shoulder arthroplasty (TSA) remains understudied. The purpose of this study is to investigate the effect of MetS on postoperative 30-day adverse outcomes following TSA.

Methods

The American College of Surgeons National Surgical Quality Improvement Program database was queried for all patients who underwent TSA between 2015 and 2020. After exclusion criteria, patients were divided into MetS and no MetS cohorts. MetS patients were defined as presence of hypertension, diabetes, and body mass index > 30 kg/m2. Bivariate logistic regression was used to compare patient demographics, comorbidities, and complications. Multivariate logistic regression, adjusted for all significant patient demographics and comorbidities, was used to identify the complications independently associated with MetS.

Results

A total of 26,613 patients remained after exclusion criteria, with 23,717 (89.1%) in the no MetS cohort and 2896 (10.9%) in the MetS cohort. On multivariate analysis, MetS was found to be an independent predictor of postoperative pneumonia (odds ratio [OR] 1.61, 95% confidence interval [CI] 1.02-2.55; P = .042), renal insufficiency (OR 4.09, 95% CI 1.67-10.00; P = .002), acute renal failure (OR 4.17, 95% CI 1.13-15.31; P = .032), myocardial infarction (OR 2.11, 95% CI 1.21-3.69; P = .009), nonhome discharge (OR 1.41, 95% CI 1.24-1.60; P < .001), and prolonged hospital stay > 3 days (OR 1.44, 95% CI 1.25-1.66; P < .001).

Conclusion

MetS was identified as an independent risk factor for postoperative pneumonia, renal insufficiency, acute renal failure, myocardial infarction, nonhome discharge, and prolonged hospital stay following TSA. These findings encourage physicians to medically optimize MetS patients prior to surgery to limit adverse outcomes.

Factors that increase the rate of periprosthetic dislocation after reverse shoulder arthroplasty

INTRODUCTION

Reverse shoulder arthroplasty (RSA) is considered one of the greatest technological innovations in shoulder reconstruction surgery, as evidenced by the fact its growth rate of usage is greatest among all shoulder arthroplasties. However, like all arthroplasties, a post-surgical complication often arises. One of these complications, periprosthetic dislocation (PPD), requires revision and poses, therefore, a burden on both patients and healthcare providers. While PPD is understood to be a complication of RSA, it is unclear to what extent certain risk factors and co-morbidities predispose patients to post-RSA PPD. The purpose of this study was to identify and evaluate the impact of specific risk factors and co-morbidities that contribute to the development of PPD following RSA.

METHODS

In this retrospective study, we used the Nationwide Inpatient Sample (NIS) database from 2016-2019 to analyze the prevalence and impact of various risk factors and co-morbidities on the incidence of PPD following RSA. A univariate and subsequent multivariate logistic regression model was made to provide a descriptive association between variables that impact the rates of PPD after RSA.

RESULTS

The NIS database identified 59,925 patients, 1,000 of whom experienced a PPD while the remaining 58,825 were placed in the non-PPD group (controls). The PPD group consisted predominantly of females (53.10%) and Caucasians (86.30%). There was a higher incidence of tobacco-related disorders (P = 0.003), obesity (P < 0.001), morbid obesity (P < 0.001), liver cirrhosis (P < 0.001), and Parkinson's disease (PD) (P < 0.001) in PPD patients compared to controls. Young patients had a 1.89-fold increased odds (OR: 1.89, 95% CI [1.58, 2.26], P < 0.001), patients with tobacco-related disorders had decreased odds (OR: 0.80, 95% CI [0.67, 0.97], P = 0.02), morbidly obese patients had 1.50 times the odds (OR: 1.50, 95% CI [1.14, 1.97]), liver cirrhosis patients had 2.67-fold increased odds (OR: 2.67, 95% CI [1.55, 4.60], P < 0.001), and Parkinson's disease patients had 2.66 times the odds (OR: 2.66, 95% CI [1.78, 3.96], P < 0.001) to develop PPD following RSA compared to patients who did not have the corresponding condition.

CONCLUSIONS

Patients with specific risk factors and co-morbidities are predisposed to developing PPD after RSA. Risk factors that were found to be associated with a higher incidence of PPD are gender (female), race (Caucasian), and age (young patients). Analysis revealed the history of tobacco-related disorder, obesity, morbid obesity, liver cirrhosis, and Parkinson's disease increased the odds of developing PPD following RSA. These findings can inform both healthcare providers and patients to improve RSA surgical outcomes and tailor post-surgery recovery programs to fit the patient's needs.

How using body mass index cutoffs to determine eligibility for total shoulder arthroplasty affects health care disparities

BACKGROUND

The prevalence of obesity in the United States is continuously rising and is associated with increased morbidity, mortality, and health care costs. Body mass index (BMI) has been used as a risk stratification and counseling tool for patients undergoing total joint arthroplasty in an effort to focus on outcome-driven care. Although the use of BMI cutoffs may have benefits in minimizing complications when selecting patients for total shoulder arthroplasty (TSA), it may impact access to care for some patient populations and further increase disparities. The purpose of this study is to determine the implications of using BMI cutoffs on the eligibility for TSA among different ethnic and gender patient populations.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify 20,872 patients who underwent anatomic and reverse TSA between 2015 and 2019. Patient demographics, including age, sex, race and ethnicity, and BMI, were compared between eligible and ineligible patients based on BMI for 5 cutoff values: 30, 35, 40, 45, and 50 kg/m2.

RESULTS

Of the total patient population studied, the mean age was 69 years, 55% were female, and the mean BMI was 31 kg/m2. For all BMI subgroups, there were more ineligible than eligible patients who were female or Black (P < .001). The relative rate of eligibility for Black patients was lower in each BMI cutoff group, whereas the relative rate of eligibility for White and Asian patients was higher for each group. There were more eligible than ineligible Asian patients for BMI cutoffs of 30 and 35 kg/m2 (both P < .001), and there were no differences in eligibility and ineligibility in Hispanic patients (P > .05). Furthermore, White patients were more eligible than ineligible for all BMI cutoff groups (P < .001).

CONCLUSIONS

Enforcing BMI cutoffs for access to TSA may limit the procedure for female or Black patients for all BMI cutoffs, thus furthering the health care disparities these populations already face. However, there are more eligible than ineligible White patients for all BMI cutoff groups, which indicates a disparity in the access to TSA based on sex and race. Physicians may inadvertently increase health care disparities observed in TSA if they use BMI as the sole risk stratification tool for patients, even though BMI has been known to increase complications after TSA. Moreover, orthopedic surgeons should only use BMI as one of many factors in a more holistic process when determining if a patient should undergo TSA.

Effects of increased body mass index on one year outcomes following soft tissue arthroscopic shoulder instability repair

Background

The purpose of this study was to investigate the impact of high body mass index on the 1-year minimal outcome following arthroscopic shoulder stabilization.

Methods

Patients who underwent arthroscopic Bankart repair (ABR) between 2017 and 2021 were identified and assigned to 1 of 3 cohorts based on their preoperative body mass index: normal (18-25), overweight (25-30), and obese (>30). The primary outcomes assessed were postoperative shoulder instability and revision rates. The 3 groups were compared using the Patient-Reported Outcomes Measurement Information System (PROMIS) upper extremity, pain interference, pain intensity, Clinical Global Impression scores, visual analog scale pain scores, and shoulder range of motion at 1 year postoperatively.

Results

During the study period, 142 patients underwent ABR and had an average age of 35 ± 10 years. Obese patients had a higher percentage of partial rotator cuff tears (60% vs. 27%, odds ratio: 3.2 [1.1, 9.2]; P = .009), longer mean operative time (99.8 ± 40.0 vs. 75.7 ± 28.5 minutes; P < .001), and shorter time to complication (0.5 ± 0 vs. 7.0 ± 0 months; P = .038). After controlling for confounding factors, obesity was associated with a lesser improvement in upper extremity function scores (obese vs. normal: -4.9 [-9.4, -0.5]; P = .029); although this difference exists, found future studies are needed to determine the clinical significance. There were no differences in patient reported outcome measures, recurrence rate, or revision surgery rates between cohorts at any time point (P > .05).

Conclusion

Obesity is an independent risk factor for longer operative times but does not confer a higher risk of recurrent instability, revision surgery, or lower outcome scores 1 year following ABR.