Off-Road Vehicle Trauma in Southern California: Association With the Social Vulnerability Index

Abstract

Background

Off-road vehicles’ (ORVs) inherently unstable design lends to higher injury rates compared to motorcycles. California has ranked among the top five states for ORV-related injuries and deaths for the past decade. Because ORVs are frequently used in rural areas with greater social vulnerability, concerns exist that injuries disproportionately affect disadvantaged populations. This study evaluates whether ORV injury rates and severity are associated with the Centers for Disease Control and Prevention’s Social Vulnerability Index (SVI) in Southern California.

Methods

We performed a retrospective cohort study of 574 adult ORV trauma patients treated at a single level 1 trauma center between 2019 and 2024. Home ZIP codes determined patient classification into Low (0-0.249), Low-Medium (0.25-0.49), Medium-High (0.5-0.749), and High (0.75-1) SVI groups. The Injury Severity Score (ISS), Glasgow Coma Scale (GCS), and Abbreviated Injury Scale (AIS) assessed injury severity.

Results

The cohort was predominantly male (88%) with a median age of 32 years (IQR 21.25). 388 (67%) patients reported helmet use. Extremity injuries were the most common (upper: 66% and lower: 52%), followed by thoracic injuries (42.3%). Most patients resided in High SVI ZIP codes (54.3%), with 25.5% in Medium-High, 15.1% in Low-Medium, and 5.1% in Low SVI areas (P < .001). Injury severity did not differ across SVI categories based on ISS, GCS, or AIS.

Conclusion

Off-road vehicle-related injuries disproportionately affect highly vulnerable communities, despite similar injury severity across all SVI categories in Southern California. This highlights the need for targeted injury-prevention programs and provides a foundation for future investigations into SVI and ORV-related morbidity.