Upper limb injuries in road traffic accidents: The influence of airbags

Abstract

This study was designed to determine the effect of airbags on upper limb trauma in RTA victims. Correlating the nature of the accident with the injuries sustained allows hospital trauma teams to predict injuries based on mechanism. We performed a retrospective case control study of 56 patients with 116 injuries admitted to University Hospital Michigan (Level 1 trauma centre). Based on information from the Crash Injury and Engineering Network (CIREN) we correlated upper limb injury due to airbags with overall injury severity, impact direction and speed of impact (Delta V). We stratified severity according to ISS score. Upper limb regions: Above elbow, elbow to wrist, below wrist. There was no significant difference between male and females according to age, weight, ISS and Delta V. There was a significant difference in height (p lt 0.05). The majority of injuries (n = 75, 65%) occurred below elbow. On the left side (n = 47) there was a bimodal distribution of injuries, 64% below elbow and 36% above elbow. On the right side (n = 61) 77% occurred below elbow. At low overall injury severity scores (ISS lt 20, n = 76) 64% of injuries occurred below elbow, vs. 82% in higher ISS scores. (ISS gt 20 n = 40). At a higher impact velocity there were more injuries to the below elbow region (62% at DV of lt 20 mph vs. 74% at DV of gt 20 mph). At an impact direction of 0-90 degrees 96% (n = 48) of injuries occurred above wrist, 44% of these above elbow. At an impact direction of 270-360 degrees 75% (n = 38) occurred above wrist, 29% of these above elbow. The majority of injuries due to airbags occur below elbow. More severely injured patients are likely to have sustained forearm and wrist fractures. If the car is hit on the right side the driver is twice as likely to sustain an above elbow arm injury.