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Pediatric Anthropomorphic Test Devices (ATDs) are valuable tools for assessing the injury mitigation capability of automotive safety systems. The neck pendulum test is widely used in biofidelity assessment and calibration of the ATD neck, and neck moment vs. angle response requirements are the metrics typically derived from the test. Herein, we describe the basis and methods for modifying the neck pendulum such that it more closely reflects base of the neck accelerations observed by a restrained three-year old ATD in a frontal crash. As a measure of base of the neck acceleration, the x-direction chest acceleration from thirty-one restrained Hybrid III three-year-old ATDs in vehicle frontal crash tests were analyzed. The standard neck pendulum yielded a mean peak acceleration that is 1.2x the peak of vehicle base of the neck accelerations, 1.6x the average, and 0.24x the duration.

Comparative data of thoracic compression response between live vs. post mortem human subjects (PMHS) has been reported, but the live subject tests are often at low deflections and include the effects of muscle tensing. Novel technology has been developed that overcomes several of these limitations. Specifically, a load cell and accelerometer has been integrated into a clinical monitor-defibrillator to measure chest compression and applied force during live human cardio-pulmonary resuscitation (CPR). The sensor is interposed between the hands of the person administering CPR and the sternum of the patient. The objective of this study was to compare the thoracic force-deflection measured during adult CPR to that measured during hub-based loading of adult PMHS. CPR represents a unique setting in which to study the mechanics of the chest as the thorax is loaded to a maximum chest deflection similar to that seen in a frontal crash environment and the effects of muscle tensing are minimized.

Successful development of side impact safety systems for rear row child occupants requires an understanding of injury causation and mitigation. However, data to guide the design of such safety systems for seat belt-restrained occupants is limited to injury risk assessments. Thus, we sought to elucidate Injury Causation Scenarios (ICS's) in children restrained by seat belts in nearside impacts. Included in the study were 4 to 15 year old children, involved in a side impact, seated on the nearside in the rear rows, restrained by a seat belt alone (no booster seats or side airbags) and who received an AIS 2+ injury. A Contact Point Map summarized the vehicle components that contribute to the injuries. The majority of head and face contacts points were found horizontally within the rear half of the window, and vertically from the window sill to the center of the window, and were a result of contact with both interior structures and structures on the crash partner.

Far-side side impact loading of a seat belt restrained occupant has been shown to lead to torso slip out of the shoulder belt. A pretensioned seat belt may provide an effective countermeasure to torso rollout; however the effectiveness may vary with age due to increased flexibility of the pediatric spine compared to adults. To explore this effect, low-speed lateral (90°) and oblique (60°) sled tests were conducted using male human volunteers (20 subjects: 9-14 years old, 10 subjects: 18-30 years old), in which the crash pulse safety envelope was defined from an amusement park bumper-car impact. Each subject was restrained by a lap and shoulder belt system equipped with an electromechanical motorized seat belt retractor (EMSR) and photo-reflective targets were attached to a tight-fitting headpiece or adhered to the skin overlying key skeletal landmarks.

Little is known about the mechanism of pelvic injury in the pediatric population, an age range over which the pelvis undergoes tremendous structural change. We hypothesize that these structural changes influence pelvic fracture injury mechanisms. A probability sample of children under age 16 years in crashes were enrolled in an on-going crash surveillance system which links insurance claims data to telephone survey and crash investigation data. 15,725 children in side impact collisions were studied. Risk of pelvic fracture in side impact collisions was estimated and factors associated with these injuries were identified. Eight cases were examined using in-depth investigation to identify the injury mechanisms. Of our study sample, 0.10% of children suffered a pelvic fracture. The typical child with a pelvic fracture was a 12-15 year old female front row occupant of a passenger car involved in a struck side collision with intrusion.

Previous research has suggested that the pediatric ATD spine, developed from scaling the adult ATD spine, may not adequately represent a child's spine and thus may lead to important differences in the ATD head trajectory relative to a human. To gain further insight into this issue, the objectives of this study were, through non-injurious frontal sled tests on human volunteers, to 1) quantify the kinematic responses of the restrained child's head and spine and 2) compare pediatric kinematic responses to those of the adult. Low-speed frontal sled tests were conducted using male human volunteers (20 subjects: 6-14 years old, 10 subjects: 18-40 years old), in which the safety envelope was defined from an amusement park bumper-car impact.

A correctly used child restraint system (CRS) is associated with a substantial reduction of injury and mortality risks in motor vehicle crashes and epidemiologic data suggests that toddlers are provided greater protection when restrained in a rearward-facing CRS compared to a forward-facing CRS. Some ‘extended-use’ European CRS models can accommodate children up to six years rearward-facing and have a support (load) leg and/or a pair of lower (Swedish) tethers to reduce rotation during frontal and rear impacts, respectively. Laboratory studies have found that a support leg reduces head and neck injury metrics of anthropomorphic test devices (ATDs) younger than three years in rearward-facing CRS models during frontal impacts.