An overview of upper extremity injuries to car occupants in UK vehicle crashes

To date, little is known about the biomechanics and epidemiology (in car crashes) of upper extremity injury and yet this body region, consisting of the shoulder, arms and hands is perhaps the most useful and versatile segment of the human body. Injury to this region is rarely life threatening but can produce impairment and disability. In this study, specifically AIS 2+ upper extremity injuries (most of which were fractures) were examined. In frontal struck side and rollover crashes, the risk of these injuries was found to be higher than that of AIS 3+ injuries to the head, chest or abdomen. In frontal crashes the outboard limb was the most frequently injured at AIS 2+. Shoulder injury sources were identified as the seat belt and wrist-hand injury sources were identified as ‘fling’ into the side door structures and A-pillar. Injury contacts and mechanisms were difficult to determine for arm and forearm injuries and future study of x-rays to determine the fracture load paths was recommended. Struck side occupants also sustained AIS 2+ injuries predominantly to the outboard limb, associated with impact to intruding side structures. The inboard limb however, was injured frequently and there were indications that those injuries were caused by interaction with an adjacent occupant. This study has produced a biomechanical reference, perhaps for the first time, of the types of upper extremity injuries that occur in crashes and provides a comparison reference which can be used to assess the contribution of airbags toward upper extremity injury.