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Computer simulations and experimental tests were used to examine the effect of humerus orientation on upper extremity interaction with a deploying airbag. The Articulated Total Body program was used to simulate testing of three upper extremity positions ranging from 0° to 90° abduction. Results indicated little difference in peak forearm bending moment for the three positions, a finding which was confirmed with experimental tests of airbag deployment into an SAE 5th % female dummy arm in the 0= and 90= positions. A comparison of simulation and dummy testing with experiments run using cadavers resulted in the conclusion that forearm position, not humerus orientation, plays a critical role in determining upper extremity injury during airbag deployment. Thus, both 0= and 90= abduction tests were found to be valid methods for studying arm/airbag interaction while preserving the rest of the cadaver for future testing.

The structural properties of the four major human knee ligaments were investigated at different loading rates. Bone-ligament-bone specimens of the medial and lateral collateral ligaments and the anterior and posterior cruciate ligaments, obtained from post-mortem human donors, were tested in knee distraction loading in displacement control. All ligaments were tested in the anatomical position corresponding to a fully extended knee. The rate dependence of the structural response of the knee ligaments was investigated by applying loading-unloading cycles at a range of distraction rates. Ramps to failure were applied at knee distraction rates of 0.016 mm/s, 1.6 mm/s, or 1,600 mm/s. Averages and corridors were constructed for the force response and the failure point of the different ligaments and loading rates. The structural response of the knee ligaments was found to depend on the deformation rate, being both stiffer and more linear at high loading rates.

Both frontal and side air bags can inflict injuries to the upper extremities in cases where the limb is close to the air bag module at the time of impact. Current dummy limbs show qualitatively correct kinematics under air bag loading, but they lack biofidelity in long bone bending and fracture. Thus, an effective research tool is needed to investigate the injury mechanisms involved in air bag loading and to judge the improvements of new air bag designs. The objective of this study is to create an efficient numerical model that exhibits both correct global kinematics as well as localized tissue deformation and initiation of fracture under various impact conditions. The development of the model includes the creation of a sufficiently accurate finite element mesh, the adaptation of material properties from literature into constitutive models and the definition of kinematic constraints at articular joint locations.