Abstract
BACKGROUND: Social determinants of health (SDoH) are associated with increased healthcare costs across various conditions, yet their impact on orthopedic trauma remains understudied. Orthopedic injuries impose a significant financial burden on the healthcare system, but the extent to which SDoH contribute to hospitalization costs is not well established. This study evaluates the association between documented SDoH-related diagnoses and inpatient costs in orthopedic trauma using a nationally representative dataset. METHODS: A retrospective cross-sectional study of the 2016-2021 National Inpatient Sample (NIS) was conducted. Fracture-related hospitalizations were identified using the Clinical Classifications Software Refined (CCSR) for the ICD-10: International Classification of Diseases, 10th Revision (ICD-10)-CM diagnoses (INJ001-INJ006, INJ038-INJ043). The primary outcome, hospitalization cost, was adjusted to 2024 dollars using consumer price index (CPI) data. SDoH presence was determined via ICD-10 Z-codes (CCSR group FAC019). Multivariate linear regression, adjusted for demographic and clinical factors, examined cost differences between patients with and without SDoH-related diagnoses. RESULTS: A total of 1,160,566 orthopedic trauma admissions were analyzed. Patients with documented SDoH factors were younger (58 vs. 72 years; p<0.001), more likely to be Black (14.02% vs. 8.07%; p<0.001), and from the lowest income quartile (36.23% vs. 27.91%; p<0.001). They had longer hospital stays (five vs. four days; p<0.001), more ED visits (83.83% vs. 79.82%; p<0.001), and higher mean costs ($27,025 vs. $22,915; p<0.001), contributing to $26.7 billion in total costs. Compared to patients without SDoH factors, they had fewer hip fractures (23.48% vs. 35.01%; p<0.001), but more upper extremity (18.70% vs. 16.56%; p<0.001) and lower extremity fractures excluding the hip (28.27% vs. 24.40%; p<0.001). Assault-related (9.76% vs. 1.60%; p<0.001) and firearm-related injuries (2.36% vs. 0.99%; p<0.001) were also more frequent. Comorbidities were disproportionately higher, including alcohol use (23.99% vs. 6.66%; p<0.001), opioid use (7.73% vs. 2.97%; p<0.001), tobacco use (39.35% vs. 15.55%; p<0.001), and schizophrenia (8.22% vs. 1.32%; p<0.001). Key cost drivers included length of stay, procedures, and substance use. Among patients with SDoH-related diagnoses, opioid use increased costs by 6.0% (vs. 7.1% in non-SDoH), stimulant use by 9.5% (vs. 6.2%), and alcohol use by 3.2% (vs. 4.4%) (all p<0.001). CONCLUSION: Patients with documented SDoH-related diagnoses face significantly higher hospitalization costs in orthopedic trauma, driven by longer stays, greater comorbidity burden, and behavioral health conditions. Findings support the need for multi-sector strategies, including Medicaid reform, targeted prevention, and integration of social risk and behavioral health services in trauma care.