Forensic Engineering Analysis of Upper Extremity Nerve Entrapment Injury Mechanisms as Related to Rear-End Collisions

Abstract

Nerve entrapments of the median nerve, i.e., carpal tunnel syndrome (CTS) and the ulnar nerve, i.e., cu-bital syndrome (CT) are relatively common, reflecting traumatic and atraumatic mechanisms. Claims of such injuries in relation to rear-end collisions (particularly low-velocity or < 10 mph collisions) are often contested by the defense, acknowledging that there is no obvious relationship between the collision and the claimed inju-ries. Of the collision types (frontal, side, rear-end), it is the least clear how a rear-end collision can establish mechanisms for such injuries. Direct blunt trauma to the carpal tunnel region or the cubital tunnel region are unlikely in a rear-end collision. Also, “stretch” injuries due to hypermotion of either the wrist or elbow are unlikely, reflecting occupant kinematics, vehicle interior geometry, and other factors. A case study involving CTS and CT claims as a result of a low-velocity rear-end collision will be presented.