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A kinematic analysis of the head-neck unit has been conducted in 37 simulated traffic accidents in order to investigate correlations between neck response and injuries. Belted fresh human cadavers in the age range 18 to 74 years have been used as front and rear-seat passengers. The analysed data included 23 frontal collisions, impact velocity 30 km/h, 50 km/h and 60 km/h, barrier impact and 14 90°-car to car lateral collisions with near-side passengers (6 cases) as well as far-side rear-seat passengers with an in-board upper anchoring point for the shoulder belt (8 cases). The head bending angle depended on the type of the collision. At the frontal collision, the mean head bending maxima amounted 79°, the evaluated mean angular velocity maxima and angular acceleration maxima corresponded to 41 rad/s and 2208 rad/s2, the mean maximum velocity in trajectory of the head was 10 m/s, the mean maximum acceleration along the path amounted 23 g.

21 low velocity direct occipital and lateral head impacts were performed on 17 cadavers. Both damped and undamped impacts were performed at impact velocities of between 2.8 and 6.1 m/s. Head responses were measured using a 9-accelerometer array, and in 8 cases epidural pressure was measured at the contre-coup site. Base of skull and temporal fractures of AIS severity 3 or 4 were produced with undamped impacts at velocities greater than 4.0 m/s. Brain injuries were also observed; these were subdural and sub-arachnoid haematomas of AIS severity 3 or 4. Only minor cervical spine injuries were observed. Head responses were calculated from the 9-accelerometer array data. Linear centre of gravity head acceleration, HIC and angular accelerations are presented. Angular acceleration time-histories calculated with this method appear to be sensitive to local skull deformations and shock wave transmission.

Frontal, lateral and rear-end collisions with dummy occupied wheel chairs on a deceleration sled were conducted in two test series at a collision velocity of 30 km/h, and a sled deceleration of 8 and 12 g. In the first dummy test series conventional restraint systems were used; in the second test series improved restraint systems were employed. In a further series, four cadaver tests were conducted. For all tests and collision directions the HIC values, as well as the resultant acceleration at the center of gravity lay below the admissible values of Federal Motor Safety Standard 208. Despite the low thorax accelerations numerous rib fractures occurred in the cadaver tests. In two cadaver tests, injury degrees of AIS 5 were observed (multiple liver ruptures, vertebral column injuries).

At the 30th Stapp Conference an analysis was presented of human volunteer head-neck response in omni-directional impact tests. It was shown that the relative head motion can be described by a simple two-pivot analog system. The present study extends this analysis to post-mortem human subject (PMHS) tests conducted at the University of Heidelberg. Two test series similar to the human volunteer frontal impacts tests were carried out. One having an impact severity identical to the most severe human volunteer tests. A second series with higher exposure levels are used to verify the proposed analog system for higher impact levels. Test results including neck injury data for five PMHS tests will be given with special attention to trajectories of the head center of gravity, head rotations and head accelerations. It is concluded that the center of gravity trajectories for the PMHS and volunteer tests are similar for both impact levels.