LOWER EXTREMITY RESPONSE AND TRAUMA ASSESSMENT USING THE THOR-Lx/HIIIr AND THE DENTON LEG IN FRONTAL OFFSET VEHICLE CRASHES

NHTSA has recently released the documentation for manufacture and use of the Thor-Lx Hybrid III retrofit (Thor-Lx/HIIIr), an advanced lower extremity device that fits on the Hybrid III 50^th percentile male dummy at the distal femur. In order to compare the response of the Thor-Lx/HIIIr and the Denton leg in the vehicle crash environment, NHTSA conducted a series of vehicle crash tests where 40 percent of the vehicle’s frontal structure along the driver’s side engaged the EU deformable barrier. The test series consisted of 4 pairs of crash tests using a belted Hybrid III 50^th percentile adult male dummy in the driver’s position. Pairs of tests were conducted under identical crash conditions using the same vehicle make, model, and model year with the Denton legs on the dummy in one test and the Thor-Lx/HIIIr legs on the dummy in the other test. This paper presents a detailed analysis of the responses of the Hybrid III dummy and the two types of legs in the paired crash tests.

Injury assessments for the leg-foot/ankle complex using existing injury criteria for the Denton leg and recently proposed injury criteria for the Thor-Lx/HIIIr are also presented. The predicted injury outcome from each of the leg types is compared to lower extremity trauma in real world crashes.