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Carotid artery injury due to motor vehicle crash has been attributed to direct impact to the neck and stretching of the artery. This study examines the response of a finite element model of the neck and carotid arteries given a farside vehicle impact. This regional carotid artery model was developed using existing material properties and based on a spine model developed by NHTSA. The finite element model was subjected to loading conditions derived from farside PMHS tests conducted at Medical College of Wisconsin. The PMHS tests represented four inboard belt loading conditions of the neck. The belts were located high on the neck, for maximal compression of the vessel, or low on the neck, for maximal excursion of the head. There was a low speed and a high speed test for each of the belt configurations. These boundary conditions were implemented in the model and the response of the carotid was quantified using strain measurements.

The purpose of this study was to investigate the influence of arm position on thoracic response and injury severity in side impacts. A total of sixteen non-destructive side impact tests and four destructive side impact tests were preformed using four human male cadavers. Single-axis strain gages were placed on the lateral and posterior regions of ribs three through eight on the impacted side, and the lateral region of ribs three through eight on the non-impacted side. Thoracic rods attached to ribs five, seven, and nine were used to measure lateral rib deflection. For the non-destructive tests, four test conditions with different arm positions were evaluated for each cadaver by performing displacement-controlled, low-energy, lateral impacts, 16 kg at 3 m/s, with a pneumatic impactor. The results of these tests showed that the highest average peak forces, peak rib deflections, and peak rib strains were observed when only the ribs were impacted and lowest when the shoulder was impacted.

The purpose of this study was to develop injury risk functions for dynamic bending of the human femur in the lateral-to-medial and posterior-to-anterior loading directions. A total of 45 experiments were performed on human cadaver femurs using a dynamic three-point drop test setup. An impactor of 9.8 kg was dropped from 2.2 m for an impact velocity of 5 m/s. Five-axis load cells measured the impactor and support loads, while an in situ strain gage measured the failure strain and subsequent strain rate. All 45 tests resulted in mid-shaft femur fractures with comminuted wedge and oblique fractures as the most common fracture patterns. In the lateral-to-medial bending tests the reaction loads were 4180 ± 764 N, and the impactor loads were 4780 ± 792 N. In the posterior-to-anterior bending tests the reaction loads were 3780 ± 930 N, and the impactor loads were 4310 ± 1040 N. The difference between the sum of the reaction forces and the applied load is due to inertial effects.

Computer simulations, dummy experiments with a new enhanced upper extremity, and small female cadaver experiments were used to analyze the small female upper extremity response under side air bag loading. After establishing the initial position, three tests were performed with the 5th percentile female hybrid III dummy, and six experiments with small female cadaver subjects. A new 5th percentile female enhanced upper extremity was developed for the dummy experiments that included a two-axis wrist load cell in addition to the existing six-axis load cells in both the forearm and humerus. Forearm pronation was also included in the new dummy upper extremity to increase the biofidelity of the interaction with the handgrip. Instrumentation for both the cadaver and dummy tests included accelerometers and magnetohydrodynamic angular rate sensors on the forearm, humerus, upper and lower spine.

This paper presents a parametric study that utilized the CVS/ATB multi-body simulation program to investigate the interaction of the hand and wrist with a door handgrip during side air bag loading. The goal was to quantify the relative severity of various hand and handgrip positions as a guide in the selection of a test matrix for laboratory testing. The air bag was represented as a multi-body system of ellipsoidal surfaces that were created to simulate a prototype seat-mounted thorax side air bag. All simulations were set in a similar static test environment as used in corresponding dummy and cadaver side air bag testing. The occupant mass and geometric properties were based on a 5th percentile female occupant in order to represent a high-risk segment of the adult population. The upper extremity model consisted of wrist and forearm rotations that were based on human volunteer data.

This paper presents a study characterizing the interaction between a small female upper extremity and a deploying side air bag. The results are based on 12 tests with small female cadavers, and 15 tests with the instrumented SAE 5th percentile female upper extremity attached to the 5th percentile Hybrid III female dummy. The upper extremity was loaded by a deploying seat mounted thoracic side air bag in a static test environment. Three types of inflators were used that varied in peak pressure and pressure onset rate. Three upper extremity positions where chosen that maximized loading to the humerus and elbow joint. Upper extremity instrumentation for both the cadaver and dummy tests included accelerometers and angular rate sensors on the forearm, humerus, and upper spine. Additional instrumentation on the cadavers included strain gage rosettes on the anterior and posterior humerus.

The air bag system is described in terms of four basic elements: the crash sensors and controls, the inflator, the air bag itself, and the diagnostic circuitry. A general discussion of these elements is provided and a review of air bag related injuries is also presented which includes data from various sources such as the University of Michigan Transportation Research Institute, National Highway Traffic and Safety Administration, Transport Canada, and the Insurance Institute for Highway Safety. The most frequently occurring accident type is the frontal collision and has been the main focus of safety efforts with regard to restraint systems. Air bags are an effective injur/prevention device, however their deployment can introduce new injury mechanisms. Air bags save lives and decrease the severity of major injuries in exchange for increasing the number of minor injuries.