Medical Conditions Related to Brain Injury
Statistics on Re-occurrence of Traumatic Brain Injury
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Traumatic brain injuries (TBI ) are a major public health issue, as approximately two million events are estimated to occur annually in the United States. The actual numbers are imprecise due to the likelihood of under-reporting events felt not to be of concern. Most of these are minor in nature and may not lead to sequelae or necessitate treatment. However, a significant number of survivors experience subsequent injuries or even multiple injuries. Repetitive head injuries (RHI) are being investigated more frequently and especially as relates to athletic related occurrences. Overall, it is estimated that a TBI survivor is 3 times more likely to experience a second injury and persons with 2 previous injuries are 8 times more likely to suffer a 3rd event. Studies show that there is an increased risk of neurocognitive deficits with subsequent injuries. Furthermore, there are reports showing an increased risk of developing neurodegenerative disorders, such as Alzheimer’s dementia.
Certainly, direct impact can cause such injuries. However, it is important to realize that significant brain injuries may occur without external trauma. Activities in which the brain is subjected to velocity or rotation can cause intracerebral trauma (within the brain tissue itself), especially at a microscopic level. The brain is surrounded by cerebrospinal fluid but the interior surface of the skull demonstrates tremendous irregularities and ridges. These can create small areas of microtrauma. Less obviously, rotational activities can lead to twisting, partial shearing, or even tearing of microscopic structures, including neurons and vascular tissues. This is the etiology (or cause) for diffuse axonal injuries (extensive shearing in white matter areas).
What situations may contribute to the incidence of multiple brain injuries? Motor vehicle accidents, motorcycle accidents, and assaults are obvious. However, many recreational activities contribute as well. Athletic endeavors such as football, boxing, soccer, hockey and volleyball have variously been reported to have a significant number of brain injuries. For example, boxing statistics indicate approximately a 6% rate of knockouts and 1 TBI per 12 rounds of competition. High school football statistics have reported approximately 60,000 cases of traumatic injury in combined studies. There are also the less obvious sources. Stop-and-go events, such as bumper cars have been cited, as have roller coasters. In these activities, the body is moved with sudden velocity and torque, often without warning. Thus, there is no time for preparation and stabilization, which might offset the impact experienced.
So, what can be done to prevent repeated injuries? First and foremost, changes in behavior can be crucial. By not always trying to “push the envelope”, or resisting peer pressure, individuals can somewhat protect themselves from certain causes of TBI. Secondly, using proper protective equipment is important. Approved helmets, appropriate safety harnesses, proper supervision, and avoidance of influencing substances such as drugs and alcohol tremendously decrease risk. Everyone needs social activity, but limiting exposure to, and participation in, some known high-risk exercises can greatly reduce the incidence of TBI or RHI. This will correlate with being able to maintain the highest level of meaningfulness in our lives.
Dr. Gerald Bilsky graduated Magna Cum Laude from Brown University and from the University of Rochester School of Medicine. He completed a residency in Physical Medicine and Rehabilitation at the University of Rochester. Dr. Bilsky is Associate Medical Director of Brain Injury Services at Shepherd Center. He is also Medical Director of Outpatient Services.