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Mind Over Matter At 200 mph

Ryan Hunter-Reay on pit lane prior to the ABC Supply 500 at Pocono Raceway. [Chris Jones Photo]

Ryan Hunter-Reay on pit lane prior to the ABC Supply 500 at Pocono Raceway. [Chris Jones Photo]

by Allan Brewer

Ryan Hunter-Reay defied the odds and his own mortality at the ABC Supply 500 today, when he returned to the cockpit of the bright yellow and red-trimmed DHL Dallara/Honda to post a superman-like result less than 24 hours following a 138-G impact to his head during Saturday qualifications. Hunter-Reay advanced from the last spot on the last row at the start of the Verizon IndyCar Series race to finish eighth, charging hard to advance his position. At 101 Laps in the book, Hunter-Reay was actually in the lead of the race at the Pocono Raceway.

Though the public focus of Hunter-Reay’s injuries centered on a radio communication from him to his crew immediately following the crash in Turn 1 at Pocono Raceway that pointed to an orthopedic or soft tissue injury (i.e., possibly fracture or torn muscles to the hip, knee or pelvis) the real potential for serious injury or death lay in the impact sustained to the driver’s skull and brain.

Sensors in Hunter-Reay’s ear reportedly documented a blow when he struck the SAFER Barrier at 138 times the force of gravity—a staggering number but not one unheard of in serious automobile accidents on the public highways.

There’s no denying Ryan’s courage, grit, determination and commitment to entertain the tens of thousands of fans who came out on a glorious late-summer day in the Poconos to enjoy some open-wheel racing. Such devotion commands both respect and admiration, which the driver received in abundance when he appeared on the starting grid dead last but ready and raring to go.

Dr. Asghar Rezaei is an authority on automotive-related brain injury. Writing in the International Brain Injury Association, Rezaei and his colleagues have tried to shed light on the topic of brain stress and undue brain motion within the skull during injury. Their results have been cast from the perspective of laboratory-simulated crashes to study the nuances of high-powered external force delivered to the skull.

Rezaei’s research goals are quite straightforward: to promote safety, training, protection, and design of safety equipment to avoid or mitigate the results of traumatic brain injury (TBI). He notes that there is real potential for serious head injury even in the absence of concussion, or loss of consciousness, as was the case in Ryan Hunter-Reay’s accident. Indeed, Rezaei notes that torsional and rotational forces on the brain stem at the base of the cerebral cortex are potentially as life-changing and serious as those above that important center of balance and coordination.

The U.S. National Highway Traffic Safety Administration (NHTSA) has often promoted the use of the so-called “head-impact criteria, or HIC value, as a translational currency in the exchange of data regarding traumatic brain injuries (TBIs). The major limitation of the HIC is that it does not take the rotational acceleration/angular acceleration that occurs during awkwardly vectored brain assault into account.

An alternative short-hand measure of brain damage has been promoted by the Association for the Advancement of Automotive Medicine (AAAM). It is called the abbreviated injury scale (AIS) and was introduced by the AAMM as an anatomically-based coding system to classify, and describe, the severity of specific individual injuries. AIS codes range from 0 (no injury) to 6 (fatal injury). There are also a number of criteria that include the effect of rotational/angular accelerations, and within this construct comparisons have been made between the results of head acceleration, changes in brain intracranial pressure, and shear stresses when a human head falls and strikes with a rigid wall from the occipital (rear) side of the head and brain at different speeds.

The rubric applied to a force of 100 to 150 G’s of force applied to the head falls within the category of “Moderate,” or Class 2. The scale goes up to 6, an equivalent force of greater than 300 G’s, which is considered non-survivable.

The point of this discussion is to emphasize that concussion, though it is acknowledged as a sign of injury, doesn’t in and of itself state the full potential for head injury. What undoubtedly also plays a role is the stress on the brain, the rotational force applied to the centers of coordination and balance, and the consequences of those forces that need more study.

The important result of this is that “medically cleared” after a head injury like the broadside swipe that Hunter-Reay experienced may defy pure traditional tests of cortical function like “What day is it? Who is the President? How many fingers am I holding up?” when applied to racing-related TBI. Perhaps tests of coordination like those a road-side sobriety test attempts are equally as prognostic in terms of motor ability and response times—both essential skills behind the wheel at any speed.

It is an emerging area of scientific neurologic study that IndyCar and auto racing in general can lead the way in illuminating and advancing to the same ends as Dr. Rezaei: better training, improved safety and informed design of the protective headwear the committed professionals like Ryan Hunter-Reay who drive race cars to entertain and thrill us deserve.

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Allan Brewer covers IndyCar and other racing series for RacingNation.com. Allan is a fixture at the race track, armed with keyboard and camera, eager to take you inside open-wheel sport where the news is being made. He comes to RacingNation.com with multiple professional awards from the American Auto Racing Writers and Broadcasters Association (AWWRBA). He began his motorsports writing career at FastMachines.com; and solely published IndyProRacer.com and A1GP.com, two award-winning websites for open-wheel racing’s junior leagues, prior to becoming IndyCar correspondent at Motorsport.com. He has also covered Formula 1, NASCAR, Formula E, the Indy Lights Series and its predecessor Indy Pro Series, NHRA events and major auto shows. His major interest outside of competition is automotive technology and its application to the cars we drive every day on the public highways.