Paper 06: Lower Socioeconomic Status is Associated with Recurrent Shoulder Instability Before Surgical Shoulder Stabilization
Authors: Moutzouros Vasilios , Enweze Lawrence , Castle Joshua , Kasto Johnny , Gasparro Matthew , Pratt Brittaney , Abbas Muhammad , Jiang Eric , Muh Stephanie 
Published: August 2024

Objectives: Social determinants of health (SDOH) are comprised of a patient’s environmental conditions including social and economic factors, which influence access to health care and resources. Growing evidence in orthopaedic surgery has revealed that SDOH factors lead to differential access to care and ultimately health disparities after surgery. For shoulder instability, previous literature has demonstrated that the number of previous dislocations before a stabilization procedure increases the risk of recurrent instability after the procedure. The purpose of this study was to investigate the impact of SDOH on the number of dislocation events before surgical intervention. Methods: A retrospective review of patients who underwent shoulder stabilization surgery at a health system in a large metropolitan area between January 1, 2021 and April 13, 2023 were identified. Patients’ demographic and social determinants variables were extracted using the electronic medical record. Social Vulnerability Index (SVI) socioeconomic subscore and Area of Deprivation Index (ADI) were collected using online mapping data based on patient zip codes. The number of dislocation events and the time they occurred were determined using clinical charts. Operative variables collected included the date of surgery to determine the time from clinical presentation to surgery and the procedure performed. Univariate linear regression analysis was used to evaluate potential predictors of increasing time to presentation and increasing time to surgery. Univariate logistic regression analysis was also performed of all potential predictors of having >1 dislocation event. A multivariate model was then created using all predictors with a P value < 0.05 in the univariate models. Results: There were 106 patients who underwent shoulder surgery for instability, including arthroscopic and open stabilization, and had complete social determinant data, with 54% (n = 57) identifying as White, 29% (n = 31) as Black/African American, and 17% (n = 18) as other. A total of 38 (35.8%) patients suffered 1 dislocation (single dislocation cohort) before undergoing surgery, and 68 (64.2%) experienced > 1 dislocation (recurrent cohort) before surgery. No significant variables were associated with increasing time to presentation or surgery. Univariate logistic regression revealed that decreasing age (odds ratio [OR] 0.94 [95% confidence interval (CI) 0.89- 0.99]; P = 0.02), decreasing body mass index (BMI) (OR 0.90 [95% CI 0.83-0.98]; P = 0.02), increasing SVI (OR 1.21 [95% CI 1.05-1.38]; P = 0.006), and increasing area deprivation index (ADI) (third tercile compared to first, OR 6.04 [95% CI 2.05-17.8]; P = 0.003) were associated with increased odds of having > 1 instability event before surgical intervention. There was no association with race found in terms of number of dislocations before surgery. Multivariate logistic regression modeling revealed that decreasing BMI (OR 0.87 [95% CI 0.78-0.98]; P = 0.02) and increasing ADI (third tercile compared to first tercile, OR 7.46 [95% CI 1.26-44.2]; P = 0.02) were associated with increased odds of having > 1 instability event before shoulder instability surgery. Conclusions: Lower socioeconomic status, as measured by ADI, is an independent predictor of a higher likelihood of recurrent instability before shoulder stabilization surgery. Recognizing these relationships may motivate surgeons to create pathways to prevent these treatment disparities among shoulder instability patients. Further studies are required to examine if these SDOH variables lead to disparities in postoperative outcomes.