Jacksonville Jaguars wide receiver Lamaar Thomas (center) is hit in the head by Tampa Bay Buccaneers linebacker Brandon Magee as cornerback Kip Edwards helps make the tackle a 2014 preseason game. Magee was penalized for the hit. Phelan M. Ebenhack/AP hide caption
Jacksonville Jaguars wide receiver Lamaar Thomas (center) is hit in the head by Tampa Bay Buccaneers linebacker Brandon Magee as cornerback Kip Edwards helps make the tackle a 2014 preseason game. Magee was penalized for the hit.Phelan M. Ebenhack/AP
As the country starts to get back into its most popular professional team sport, there is a reminder of how dangerous football can be.
An updated study published Tuesday by the Journal of the American Medical Association on football players and the degenerative brain disease chronic traumatic encephalopathy reveals a striking result among NFL players.
The study examined the brains of deceased former football players (CTE can only be diagnosed after death) and found that 110 out of 111 brains of those who played in the NFL had CTE.
CTE has been linked to repeated blows to the head — the 2015 movie Concussion chronicled the discovery of CTE's connection to football.
In the study, researchers examined the brains of 202 deceased former football players at all levels. Nearly 88 percent of all the brains, 177, had CTE. Three of 14 who had played only in high school had CTE, 48 of 53 college players, 9 of 14 semiprofessional players, and 7 of 8 Canadian Football League players. CTE was not found in the brains of two who played football before high school.
According to the study's senior author, Dr. Ann McKee, "this is by far the largest [study] of individuals who developed CTE that has ever been described. And it only includes individuals who are exposed to head trauma by participation in football."
The fact that we were able to gather this many cases [in that time frame] says this disease is much more common than we previously realized.
Dr. Ann McKee
A CTE study several years ago by McKee and her colleagues included football players and athletes from other collision sports such as hockey, soccer and rugby. It also examined the brains of military veterans who had suffered head injuries.
The study released Tuesday is the continuation of a study that began eight years ago. In 2015, McKee and fellow researchers at the Department of Veterans Affairs and Boston University published study results revealing 87 of 91 former NFL players had CTE.
McKee is chief of neuropathology at VA Boston Healthcare System and director of the CTE Center at the BU School of Medicine. Speaking about the new numbers, she says it's "startling to be able to gather 177 examples of CTE" in a relatively short period of time (the past eight years).
"While we still don't know what the incidence is in the general population or in the general population of football players," she says, "the fact that we were able to gather this many cases [in that time frame] says this disease is much more common than we previously realized."
Caveats and cautions
McKee cautions, however, that researchers cannot extrapolate from the numbers and come to conclusions about CTE.
All the brains studied were donated, she says. "Families don't donate brains of their loved ones unless they're concerned about the person. So all the players in this study, on some level, were symptomatic. That leaves you with a very skewed population."
Still, McKee is adamant about one point.
"We're seeing this [CTE] in a very large number that participated in football for many years. So while we don't know the exact risk and we don't know the exact number, we know this is a problem in football."
Longtime concussion expert Dr. Munro Cullum says the study is helpful for several reasons. "It obviously adds to the cases in the literature," he says. "It has expanded the age range [of those with CTE] beyond just retired NFL players. And [researchers] did find increasing CTE pathology in the cases [of players] who were older. That's all useful information."
But Cullum, a neuropsychologist with the O'Donnell Brain Institute at University of Texas Southwestern Medical Center who has studied concussions at all levels of sport for nearly three decades, says it's still too soon to definitively declare CTE a problem in football.
"It seems to be, perhaps, more common in people who play football," he says, "but we don't know why. We actually don't know what the causative factors are or the risk factors [for CTE]. There still are probably yet to be discovered genetic and environmental factors that could be contributing as well."
Cullum notes all the attention is on football right now.
"It depends on where you're shining the light," he says. "We have to be very careful. If all I study is condition x or y, and I find that in the sample that I'm sent, what about the 99 percent of all the other samples?"
A desire for more research
Cullum and McKee agree on one thing: There has to be additional studies and more money for research.
"We need a very well-constructed longitudinal study," says McKee, "looking at young individuals playing these sports. We need to follow them for decades. We need to take measurements throughout their lives and playing careers so we can begin to detect when things start to go wrong. If we can detect early changes, that's when we could really make a difference."
McKee says researchers need tens of millions of dollars, even $100 million, to conduct the necessary research.
"We need a lot of funding," she says, noting that the researchers are working with a grant from the National Institute of Neurological Disorders and Stroke that ends in December. "It's always tricky for us to get funding."
She has submitted applications for funding into next year, she says, but she is not sure they will be granted. "There's so much discussion of this disease not existing that funding agencies are reluctant to consider this a real neuro-degenerative disease.
"But I think we've proven beyond a doubt this is."
And the attention should extend beyond football, McKee adds. "I think any sports organization that has participants that are exposed to head trauma needs to endorse this research and support it."
The organization on the CTE hot seat, the NFL, says it has done so.
In a statement provided to NPR, the NFL said it values what McKee is doing and is committed to supporting CTE research:
"We appreciate the work done by Dr. McKee and her colleagues for the value it adds in the ongoing quest for a better understanding of CTE. Case studies such as those compiled in this updated paper are important to further advancing the science and progress related to head trauma. The medical and scientific communities will benefit from this publication and the NFL will continue to work with a wide range of experts to improve the health of current and former NFL athletes. As noted by the authors, there are still many unanswered questions relating to the cause, incidence and prevalence of long-term effects of head trauma such as CTE. The NFL is committed to supporting scientific research into CTE and advancing progress in the prevention and treatment of head injuries."
The statement continues, "In 2016, the NFL pledged $100 million in support for independent medical research and engineering advancements in neuroscience related topics. This is in addition to the $100 million that the NFL and its partners are already spending on medical and neuroscience research."
But McKee is skeptical of the NFL's promises to fund research. "I will be extremely surprised if any of the 100 or 200 million comes my way," she said in response to the league's statement. "The NFL directs funding only to research they approve of."
The NFL has funded a portion of her past research, but in McKee's view, there will be "no continued NFL support" because "the results are considered too damaging."
Despite the NFL's statement supporting McKee, the league wasn't always a willing partner of CTE research. Many accused the NFL of denying, or even covering up, the link between football-related head injury and brain disease. As part of a massive concussion lawsuit settlement with thousands of former NFL players, reached in 2013, the league didn't have to acknowledge any wrongdoing.
But the NFL has responded to the concussion issue, instituting new policies and enforcing existing rules to better protect players.
The moves to protect football players are important, says Cullum, despite the uncertainties still surrounding CTE and concussions.
"Obviously any brain injury is not good," he says. "But right now, we don't know how many concussions are too many or for whom."
McKee anticipates her study will become part of the ongoing discussion about football's future and whether young people should play the game.
"I'm worried about these numbers steering the conversation in that these numbers are of a very biased brain donation research," she says. "But the fact that we found [CTE in 177 players] is cause for concern."
"While I'm not willing to say football is doomed and I also am unwilling to make a decision [on a young person playing football] for other individuals ... I think there's a risk to playing football," she adds.
McKee says she does suspect the "longer and higher" the level a player goes, the more likely it is that player gets CTE, but reiterates that more research is needed "to really come up with the answers."
“Sports are second only to motor vehicle crashes as the leading case of traumatic brain injury among persons aged 15 to 24 years” (Gessel 495), which is why sport injuries, in football for instance, is a topic that has attracted a lot of attention whether it is from fans, scientists, athletes, or investors. Tremendous amounts of capital are invested in football programs, especially at the collegiate and professional level, which is one of the main reasons why keeping players healthy is very important. Fans want to see their favorite players on the field and coaches expect these players to win games for them. This research work will focus on one of the most popular and repeated injuries in football: concussions. Over the past decade, several experts have undertaken large numbers of studies in order to tackle the biomechanics and short- and long-term effects of concussions on football athletes. Furthermore, the innovations in technology have allowed research on concussive brain-injuries to significantly improve. These improvements have allowed researchers to develop new equipment in order to protect the players, but most importantly, have allowed coaches and physical trainers to be much more aware of the symptoms and dangers surrounding concussions. Why should we worry about concussions in a sport like football? Many factors influence scientists in making this decision. Concussive brain injuries are the result of violent impacts to the head damaging tissues of the brain, and are one of the top injuries that football players and athletic trainers must deal with, which is true for all levels of play, whether it is at the high school or the professional level. Football players are exposed to these brain injuries because of the major impacts that they encounter when making tackles and/or taking hits from an adversary.
As proposed by many experts in the field of sport-related injuries, the best way to prevent concussions is by studying their biomechanics and by improving awareness about their short- and long-term effects on injured players. This concept will be heavily used throughout this entire paper. The objective of this work is to increase the flow of information about concussions in football and facilitate its access for athletes, coaches, and fans by putting many previous scholarly works and studies all together in one document. American football involves millions of players and I believe that they should be aware of the risks that they are exposed to in playing their favorite sport.
This research is an attempt to enter to field of exercise and sport-science, where thousands of professional institutes and organizations, such as the NCAA (National Collegiate Athletic Association), have invested large amounts of money to understand the effects of concussive injuries and to improve their prevention. In investigating the biomechanics of concussions, nationally recognized experts such as Dr. Jason Mihalik were able to formulate and explain how concussive injuries are occurring in football players. In his work, "Measurement of Head Impacts in Collegiate Football Players: Relationship Between Head Impact Biomechanics and Acute Clinical Outcome After Concussion," published in 2007, Dr. Mihalik explains in details how concussions are the results of blows to the head or to other parts of the body, resulting in fast accelerations/decelerations of the brain, colliding on opposite sides of the skull. Other well-recognized experts, such as Dr. Michael McCrea and Dr. Kevin Guskiewicz, have explored a different field of concussions by investigating their short-term effects and their recovery rates, as well as the implications involved with repetitive injuries. These findings have allowed medical staff and physical trainers to identify these types of injuries much more efficiently. In addition to that, more and more scientists, such as Stephen Marshall and his work published in 2005, “Association between Recurrent Concussion and Late-Life Cognitive Impairment in Retired Professional Football Players”, have investigated how concussions increase the likelihood for depression, dementia, and other long-term brain-related diseases, such as Alzheimer’s disease and Parkinson’s syndrome.
Based on knowledge acquired through the use of multiple recent studies done by experts in the field of concussions and sport injuries, and also based on the help and expertise of Dr. Kevin Guskiewicz, a 2011 MacArthur Fellow for his work on concussive brain injuries, I argue that the best way to prevent concussions is by studying their biomechanics and by improving awareness about their short and long-term effects. These studies show evidence that concussions can change one’s life significantly and that a single impact can be fatal to cognitive health. Throughout my work, I am arguing that making athletes more aware of the risks to which they are exposed to as football players and changing their behavior on the field can reduce the rates of concussions on a large scale. More importantly, the use of innovative technological tools and well-trained medical staff can help us reducing by significant amounts, the rates of the concussive injuries in football players, from high school to professional athletes, by changing players’ behavior on the field and by providing sufficiently good protective gear. This is a new and innovative branch of research on concussive injuries, which is available to us because of the improvements that have been made in technologies. Experts such as Dr. Guskiewicz, Dr. Mihalik, and others mentioned above have investigated different topics related to concussions and have proven that these concussive impacts can have significant life-changing consequences. This paper attempts to bring these reasonings to another level and to prove that these dangerous rates of head injuries can in fact be reduced through changing players’ behavior.
This work will look at the short- and long-term effects of concussions on injured players as well as how players playing are exposed to different patterns of post-injury recovery rates. I will then investigate the impacts of repetitive injuries and how athletes are exposed to different likelihoods of contracting a concussion. Factors such as position played in football, type of plays usually ran by the athlete (defense vs. offense) and type of impacts (front, back, sides), will be looked at. Lastly, the main goal of this paper is to prove how innovation in technology allows medical staff and scientists to change the behavior of players, which is a key factor in decreasing the rates of concussions on the football field.
Biomechanics of concussions
As discussed in the introduction, concussions are injuries that football players are strongly exposed to because of factors such as the equipment used, the speed of the game, and the hits that they are required to do and take. As described in an article written by Mark Derewicz, concussive brain injuries are the result of a violent movement of the brain colliding on the opposite side of the skull, following an impact to a player’s head, generating a relatively high gravitational force (par. 6). A study on biomechanical properties of concussions conducted by Dr. Jason Mihalik has shown that the “majority of concussions occurred as a result of impacts [recorded] above 80 G” (1250). The way these impact measurements are taken and tested on athletes will be addressed later in this essay. A concussion is a rapid acceleration/decelaration injury where the forces from a certain impact are transmitted to the brain. In the same study, Mihalik explains how concussions are “believed to be the results of dynamic loading,” which is one of the two ways loading of a certain force can be initiated (1250). This dynamic loading is the result of a “direct blow to the head or a sudden [impulsive] movement of the head produced by impacts elsewhere on the body” (1250). These findings split concussive impact injuries into two types: the ones resulting from a direct hit to the head and the ones resulting from a rapid movement of the head. After looking at multiple concussions and the impact locations on helmets of players, Mihalik, as well as many other researchers coming with the same results, end up concluding that most concussive brain injuries are the results of collisions being absorbed from the top of the helmets. The image in appendix 1.1 shows the results of impact locations from the study. As one can see, impacts taken from the front of the helmets were second in terms of concussions risks fallowed by side and back impacts.
Short-term effect of concussions
The physiological effects of concussions, in the short term, is a topic that has been heavily studied by many researchers because it was the first thing that scientists had access to when first interested in the topic. Evaluation of long-term symptoms from concussive injuries only started to attract scientists later in the research process as they became more and more confident with their conclusions on short-term effects. As innovation in sport science technologies increased, more and more tools such as computer-based neurocognitive testing, video analysis, and specific brain surgeries allowed scientists to increase their degree of confidence towards the effects of concussions.
As discussed in the previous section, Biomechanics of concussions, a concussion injury is the result of a high acceleration/deceleration of the brain hitting on the opposite sides of the skull, leading to major damages of the tissues. It is usually the result of an unexpected or expected blow to the head or a rapid movement of the head. As described in a study conducted by Dr. Michael McCrea, a series of “pathophysiological” reactions follow the contact of the brain to the skull: “an indiscriminate release of excitatory amino acids, massive ionic flux, and a brief period of hyperglycosis, [which is] followed by persistent metabolic instability, mitochondrial dysfunction, diminished cerebral glucose metabolism, reduced cerebral blood flow and altered neurotransmission” (2556). As one can tell, this reaction chain creates a lot of instability in the brain and tissues surrounding it. According to the book Physical Medicine and Rehabilitation: Principles and Practice, Volume 1, published in 2005, hyper glycolysis is a situation when the levels of released glutamate (Glu), which is a key amino acid for cellular metabolism and balance, stay high for a long period of time (several days) after the injury. “This results in neuronal overexcitation without corresponding oxygen metabolism” which usually leads to the death of neurons in the brain and “neuronal acidosis,” a instable situation where calcium concentration is decreased at the neuronal level, inhibiting synaptic activity, especially in hippocampal regions, which is responsible for memory (234). Other effects of this reaction chain are lack of ATP (Adenosine Triposphate), due to mitochondrial dysfunction, which is a product of cellular respiration and used as a source of energy for many chemical reactions, and accumulation of waste within the cerebral fluid due to reduced blood flow within the cranial region, which is a situation called brain ischemia (Reece 170).
The findings of the study done by Dr. McCrea are supported by investigations made by Dr. Kevin Guskiewicz. After looking at 184 concussed football players, reporting 196 total concussions, from 25 different US colleges, Dr. Guskiewicz was able to identify “headache as the most commonly reported symptom at the time of injury (85.2%),” which was reported, by the players, to be felt for an average of 82 hours following the injury (2459). In looking at the duration of headache after the injury even more closely, 65.9% of the players reported having a headache 3 hours following the injury, 24.5% reported having headaches 24 hours after the injury, and 13.8% reported still having headaches 7 days following the initial injury day (2552). These results are astonishing when thinking about the pain and the discomfort that these players had to fight through after being initially injured.
Other more severe short-term symptoms were reported by these two studies such as “cognitive impairment [both in speed and verbal fluency], balance [and dizziness] problems” (McCrea 2560), concentration problems, sensibility to light or noise, instant fatigue, drowsiness, and memory loss (Guskiewicz 2552). The percentage of players reporting these symptoms at the time of injury, in Dr. Guskiewicz’s study, was put into a table ranking them from highest percentage to lowest one, which can be seen in Appendix 1.2.
Long-term effects of concussions
Now that we have looked at the short-term effects of concussions, we can address the long-term impacts of concussive injuries. The long-term time period consists of the years following the original brain injury and the post-career period of a certain previously concussed athletes. More and more scientists are intrigued by how concussions increase the likelihood of depressions, dementias and other brain related diseases.
TBI, traumatic brain injury (Marshall 719), is another term used by scientists when talking about concussions and other brain related injuries. It “has been identified as a potential risk factor for the occurrence (or early expression) of neurodegenerative dementing disorders, including Alzheimer’s disease (AD) and Parkinson’s syndrome, and other psychiatric disorders such as clinical depression” (Marshall 719). Alzheimer’s disease is a form of dementia usually occurring late in the life of an individual, which is characterized by “insidious onset and progressive impairment of memory and other cognitive functions” (McKhann 939). In contrast, Parkinson’s syndrome is the result of over-activity of the basal nuclei, a region of gray matter in the brain. The basal nuclei’s role is to regulate the primary motor system, which is responsible for motor movements. The basal nuclei activity is monitored by a region in the brain called substantia nigra, which releases dopamine to decrease the basal nuclei’s activity. People suffering from Parkinson’s syndrome have an affected substantia nigra region, which fails at releasing dopamine (Reece 1025, 1041).
Following the same tracts, research has recently reported that effects resulting from concussive injuries could be affected by genetic inheritance. It was found, by Dr. Stephen Marshall and others, that individuals who tested positive for the ApoE e4 gene had higher risks of developing Alzheimer’s (Marshall 720). “The human ApoE e4 encodes a cholesterol carrier lipoprotein (apolipoprotein E) that is made in the liver and brain and is important for transport of lipids in the brain” (Marshall 723). The gene also drives important functions for brain responses to injury and recovery time. The forces applied to the head as a result of a concussive impact cause the “accumulation of beta amyloid and tau proteins within hours of injury within the neuronal body” (Marshall 723), which according to the research done by Dr. Marshall, “decrease the recovery [potential] after [a] TBI” (273). The gene ApoE e4 had already been connected with TBI in boxers by previous scientists and with lower cognitive performance on baseline tests performed by football players with a history of concussions. As proposed in Marshall’s study of the effects of concussive injuries and late-life impairment in retired football players, the correlations with the appearance of ApoE e4 gene may be “suggesting that there [might] be an association between these dementia syndromes and either recurrent TBI or recurrent subconcussive contacts to the head” (Marshall 720). In the same study, Dr. Marshall reports that 60.8% of the 2552 retired football players interviewed “reported having sustained at least one concussion during their professional career”, and “24% reported sustaining three or more concussions” (721). After questioning these previously concussed players about the symptoms and impacts of their injuries, more than half of the players admitted having suffered from loss of consciousness (54%) or memory loss (52%) as a result of the concussions. More impressively, 17.6% of these retirees have reported that “they perceived the injury to have had a permanent effect on their thinking and memory skills as they have gotten older” (721). Even though this last finding is relatively subjective, it still demonstrates how much previously concussed players feel that their injury has impacted their lives. Going back to the likelihood of developing Alzheimer’s, this study also concluded that “football retires have higher prevalence than other American men of the same age” (721), which again indicates the negative impacts of concussive injuries. As the number of repetitive concussive injuries increased for a single player, as did the potential of suffering from all these long terms effects (722).
Recovery rates of concussions
Now that we have looked at both the short and long-term effects of concussive brain injuries, we can address the time it takes for athletes to return back on the field after being diagnosed with a concussion. Returning players back to the game is one of the most challenging and risky part in treating these injuries because of all the risks that players are exposed to with repetitive injuries and because of how difficult it is, for physical trainers and doctors, to be a hundred percent sure that a player has fully recovered from its injury.
In order to evaluate the symptoms in athletes and their progression during the rehabilitation, scientists and medical staff from high school to professional programs have been using an important tool called “computer-based neuropsychological testing” (Pellman 271). Before each season, athletes involved with contact sports are required to take a baseline test using a computer. These baselines tests are offered by lucrative companies like ImPACT (Applications) and are given to athletes before and after their head injuries. The first baseline test is used as a way to gather sets of data that will be compared to the results of an athlete when retaken the exact same test following a potential head injury. These types of test measure multiple aspects of the athlete’s mental activity such as reaction time, visual memory and process, working memory (sensory memory), attention span, sustained and selective attention, and non-verbal problem solving. As stated in the section titled “Overview and Features of the ImPACT test” of the product’s website, “ImPACT assists doctors in making return-to-play decisions and should never be used as a stand-alone tool.” In other words, neuropsychological baseline testing is only used to help doctors and physical trainers diagnose concussions and to determine if a player is or not ready to go back to the field. The overall treatment of a concussed athlete, as mentioned in Dr. Elliot Pellman’s work about concussion’s recovery rates in the NFL and in high school should involve “an assessment of the athlete’s on-field signs and symptoms, subjective report of symptoms, the observations of the medical staff present at the time of injury, as well as neuropsychological test results” (271).
In looking at the patterns of symptoms in players with a concussion, Dr. Michael McCrea has found that “[the] symptoms, cognitive impairment, and balance problems (postural instability)” (2560) were more severe at the moment and immediately following the concussive injury, and that it was “followed by a gradual improvement over the first several postinjury days” (2560). These findings are what anybody would expect. What is more interesting in Dr. McCrea’s work is that, on average, players’ symptoms tend to be resolved, allowing them to return to the field, after a seven days period. During his research, Dr. McCrea found that 91% of all his tested concussed players were returned to “personal baseline symptom levels within 7 days after concussion” (2560). In looking at each symptoms more specifically, this research also found that cognitive impairment symptoms were persistently severe throughout the first 2 days following the initial injury as opposed to balance problems who tend to be more pronounced in the first 24 hours only (2560). In similar research done by Dr. Kevin Guskiewicz on the cumulative effects of concussions, it was found that “overall symptom duration was about 3.5 days, and [that] 87.8% [of all studied subjects had] achieved full symptom resolution within 1 week after injury” (2552), which confirms the findings of Dr. McCrea. The same study by Dr. Guskiewicz also looked at the impact of returning concussed players to the field on the same day of their injury due to judgment and diagnosis errors. It was found that “players with concussion who returned to play on the same day of injury experienced delayed onset of symptoms” (2552) where they reported suffering from the post-injury symptoms, on average, three hours after the initial injury. Finally, Dr. Guskiewicz’s work found that players with a previous history of concussions tend to have longer recovery periods following their concussive injury and that those players suffering from loss of consciousness and amnesia as a result of their injury also tend recover slower (2552).
In comparing recovery rates in NFL players versus high school players, Dr. Elliot Pellman concluded that NFL players, on average, tend to recover more quickly from a concussion than high school players (270). Different hypotheses were proposed by scientists to explain this difference. Some have suggested that neurodevelopmental factors in children, such as the fact that “children are known to exhibit more diffuse and prolonged cerebral swelling after injury than adults” would expose children to “greater risk of sustaining concussion after head impact” (270). As discussed in the biomechanics section of concussions, the head injury is the result of damaged brain tissues, which results in internal swelling within the skull. Because children showed to sustain the swelling longer than adults, it is fair to assume that the repercussions of the concussion, the symptoms, should also be felt longer. A second hypothesis to explain why, on average, professional players tend to recover more quickly than high school and college players has to deal with “different tolerance for concussions” (Pellman 270) within athletes. Because NFL players represent a very “highly select group [of individuals] with regard to skill level, size and injury tolerance,” scientists have proposed that this selective process would decrease the likelihood of players to be concussed, similar to the process of natural selection proposed by Charles Darwin. “The level of conditioning and skill necessary for success in the NFL may result in athletes that are less prone to injury than younger and less talented or well-conditioned individuals” (Pellman 270). Following the same reasoning, athletes with a previous concussion history during their high school and college career may have chosen not to continue their football career in the professional level and instead found a different noncontact sport or activity that interested them. This last statement is supported by Dr. Pellman’s claim when he says: “Although this hypothesis is also speculative, it is in line with the observation that most athletes who enter the NFL do not have a significant history of concussion during their high school and college years.” All these are very reasonable to consider in order to explain the differences between NFL and high school players, especially when thinking about how big of a business the professional league is. Owners, coaches, and investors put a lot of capital into each player that they sign on the team and they want to make sure that these players will stay on the field and not always be in need for treatment and sitting with medical staff.
Implications of repetitive concussive injuries
As discussed in the previous section, returning players back to the field after being diagnosed with a concussive injury is a challenging task for physical trainers and doctors because of the important risks that surround the implications of repetitive concussions or head injuries. As claimed in Dr. Kevin Guskiewicz’s work on cumulative effects of concussions in college athletes, football players with a previous concussion history are more likely to develop further concussive head injuries and with every successive injury this likelihood is increased; “football players with a history of 3 or more previous concussions were 3 times mores likely to sustain a incident concussion than those with no concussion history” (2552). As one can tell, the risks are high with regards to players’ safety. The more one player suffers from concussions, the more likely he is to get another one. It is a positive feedback relationship where one variable increases the other. This is the reason why looking very closely at the recovery rates of athletes and making sure that they have fully recovered from their head injury is so important. In the same repetitive concussive injury work by Dr. Guskiewicz it was found that “1 in 15 players with concussions may have additional concussions in the same playing season and that these reinjuries typically take place in a short window of time (7-10 days) following the first concussion” (2553). These findings should be shown to medical staff and players before returning to play. Athletes who fall into this category need to be aware that they need to be extra careful with taking impacts and blows to their head, especially in the first and second week coming back to the field because of their hypersensibility to concussive injuries. Concussion prevention techniques like changes in behavior and equipment modifications, which will be discussed later in this paper, become even more important in these returning cases. The increase in potential future concussive injuries that players with a history fo concussion are exposed to has been suggested by Dr. Guskiewicz to be “indicative of increased [in] neuronal vulnerability [, which is followed by] recurrent concussive injuries” (2553). Studies on animals have shown that accelerated glycolysis and increased lactate production, as discussed in short-terms effect of concussions section, are “believed to leave neurons more vulnerable to secondary ischemic injury and [have] been considered a possible predisposition to repeat injury” (2553). In other words, the physiological symptoms of a previous injury would increase the likelihood of further injuries, which is the reason why many cases of repetitive concussions can be observed in football players.
One of the most extreme complications of posttraumatic repeated brain injuries is called the “second impact syndrome” (SIS). Originally diagnosed in boxers, SIS has been something that has caught scientists’ attention with regard to further issues related to concussive injuries. As described by Dr. Paul McCrory in his work, SIS “has been defined as occurring when ‘an athlete who has sustained an initial head injury, most often a concussion, sustains a second head injury before symptoms associated with the first [injury] have fully cleared’” (677). This could be the result of a player being returned to the field too early or a player getting hit on the head because of bad luck. It is believed that SIS is caused mainly from the “rapid development of cerebral vascular congestion which in turn causes increased intracranial pressure, resulting in brainstem herniation and death” (677). This diffused cerebral swelling condition is rare but a “well-recognized cause of delayed catastrophic deterioration resulting in death or persistent vegetative state” (677) following a repeated head injury. Interestingly, this rare diffuse cerebral swelling condition has only been reported in males and predominantly in teenagers, with a mortality rate approaching 100% (McCrory 682). Dr. Paul McCrory provides two different “pathophysiologic mechanics” to explain the cause of SIS. The first is “thought to be due to [an] increase [in] blood volume [due] to a failure of [the] cerebral vascular auto-regulatory mechanism” (679). Because the blood is not being pumped and moved correctly, it accumulates and increases within the brain tissues, increasing the volume. The second mechanism proposed by Dr. McCrory is due to “true cerebral edema” (679), is a situation in which there is excess of water accumulation in the intracellular and/or extracellular spaces of the brain due to a loss in integrity of the blood brain barrier (Harrigan).
As these examples show, the implications of repetitive concussive injuries are very costly to athletes and this is why it is very important to make sure that athletes are aware of the risks that they are exposed to when returning to play and that medical staff are well trained to evaluate players’ physical and psychological condition.
Rates of concussions
Different players on the field experience different likelihoods to sustain a concussion based on various factors, such as type of plays usually run by the athlete and the location of the impact on their helmet. Image 1.4 in the appendix provides a great example of how different types of plays have different percentages of players getting concussions. As it can be seen, running plays for both defensive and offensive players, especially linemen and running backs, have the highest percentage with 55.4%, which is extremely high (more than half). These findings by Dr. Gessel (499) support a reasoning proposed by Dr. Guskiewicz (2553) where he proposes that linemen and linebackers have an increased risk of concussive injury because of the increased sizes and speed that are required for these positions. Dr. Guskiewicz’s findings, the percentage of overall concussive injuries is significantly higher for linemen and linebackers, which can be seen in image 1.3 of the appendix. Because a concussion is caused by sudden acceleration/deceleration of the head and changes in forces, higher weight and speed increase the potential for an injury. When adding the fact that running plays require much more contact from the athletes than passing plays, the findings discussed above become obvious.
Another interesting set of evidences was brought by the expert Dr. Nancy Weaver in her work in collaboration with Dr. Guskiewicz. In her work “Epidemiology of Concussion in Collegiate and High School Football Players”, Dr. Weaver makes the claim that “Contact with artificial turf appears to be associated with a more serious concussion than contact with natural grass” (643). This is one of the first scientific works that proposes such a statement, and opens room for lots of questioning. Dr. Weaver emphasizes that contact with artificial turf does not necessarily seem to increase the chances of sustaining a concussion, but would be associated with the severity of the head injury. In her study, Dr. Weaver also reports that “the majority of the injuries (59.9%) occurred in game situations as opposed to practice or scrimmage events” (646) and that “the most common mechanism of injury was contact with an opponent (63.6%), followed by contact with a teammate (16.9%), contact with the ground (10.0%), and contact with equipment on the playing field (3.8%)” (646).
Based on previous studies, it was found that the location of the impact on the helmets of football players had a major impact in increasing the risks of getting a concussion. The angle and linear accelerations are measured using a specialized sensor put into players’ helmets. After looking at multiple concussions and their impact locations, Mihalik, as well as many other studies with the same results, conclude that most concussive brain injuries are the result of collisions being absorbed from the top of the helmets (1250). Players tend to take hits leaning with their head, which results in them absorbing most, if not all, of the impact forces with their head only. This increases dramatically the risk of getting a concussion and is the result of poor technique and lack of judgment. Again, we can see the benefits of changing players’ behavior.
The concussion equation
In order to visually represent concussions, Dr. Guskiewicz has created the ‘concussion equation’. It represents the pathway leading to an injury, with the initial impact affected by different variables such as the player’s position, linear and angular acceleration, location of the impact, helmet type, and play type (offence, defense, special teams). The symptoms, the chronic short and long term effects, the balance problems, and the neurocognitive function imbalances, which can be seen on the product side of the reaction, all represent the potential consequences of a concussion. This work on concussive injuries heavily uses this conceptual image shown in Appendix Image 1.5. The main concept of this paper is to prove that changing the initial variables, such as player behaviors and equipment, allows us to reduce dramatically the rates of concussions in football players. This equation works exactly like a chemical reaction; if you change the reactants, in this case, the initial variables, you change the outcomes, which are the consequences of a concussion for a specific player.
Changing Players’ behavior and Concussion Prevention Techniques
When looking at the location of impacts on players’ helmet and their high correlation with the risk of having a concussion, it is relatively safe to say that changing players’ behavior would help us decrease the rate of concussions. If players take or deliver impacts erect with their head and chest up, they are putting themselves in a much safer football position, as opposed to when they lean head first into a contact. Looking back at the concussion equation, image 1.5, changing the initial reactants can change the product side of the equation. In this case players’ behavior on the field when taking or making a hit is the reactant and avoiding the whole concussive injury is the product.
Skeptical scientists could argue that talking and writing about the benefits of changing player’s behavior on the field is very different than actually doing it and seeing evidences of the changes. Does proposing alternatives and innovative solutions using technological tools really allow us to change the way these players act on the field? My answer is yes and is supported by Alan Pelc’s story.
Alan Pelc, class of 2010, was a 6-foot-6, 308-pound offensive guard for the Tar Heels from Houston, Texas, who had all the potential to play at the professional level (Schwarz par.1). After hearing too much about head to head hits resulting in injuries and after seeing one of his fellow opponents, “Eric LeGrand, a Rutgers offensive tackle who weeks later became a quadriplegic on a head-first hit” (Schwarz 4 par.), Pelc decided that he wanted to change his playing habits, even though he had never suffered from a concussion before. He understood and was now conscious of the high risks that he was exposed to as a football player. Pelc was then taken by Dr. Kevin Guskiewicz for a clinic on ‘how to play safer and better football’ along with UNC athletic trainer Scott Trulock. After looking at several videotapes of Pelc during practices and games and after looking at the data recorded by the “accelerometers, known as the Head Impact Telemetry (HIT) system” (Schwarz par. 5) in Pelc’s helmet, the group determined that Pelc was too often using his head to give or take blows. The article written by Alan Schwarz on this work reported:
According to the HIT system data, in Pelc’s four seasons with the Tar Heels, his head had withstood 85 collisions of more than 100 G’s — comparable to a car moving 35 miles an hour hitting a concrete wall. And 20 percent of those high-impact collisions arrived through the top of his helmet, an alarmingly high rate for a lineman and an indication that he was dropping his head dangerously on blocks. (par. 11)
Dr. Guskiewicz worked with Pelc and talked him into a better and safer way to play his sport: by taking and delivering hits using more of his shoulders and by playing low with his knees bent and his chest and head up. Even though it was hard for Pelc to entirely change his behavior in a short period of time, drastic amelioration in his technique was observed 4 months later when delivering a hard blow to his opponent on a kick-off return. The play was videotaped and shows a clear evidence that changing players’ behavior is very possible and efficient. Coach Everett Withers, former Tar Heels’ defensive coordinator admitted in the interview with Schwarz that tackling technique was most definitely neglected in football (par. 16). Withers also claimed that the HIT system “‘makes [them] cognizant as coaches — Okay, here’s a guy we have to spend extra time [watching]. It makes us aware of players who struggle with leading with their head.’” As one can tell, both Alan Pelc’s story and coach Withers’ statement support the fact that innovations in technology have allowed medical staff and football programs to better train their players. These also provide solid evidence that decreasing the rates of concussions by changing players’ behavior is a reasonable and doable objective.
As previously discussed in this paper, decreasing the rate of concussive injuries in football players is something that needs to be addressed more seriously because of the multiple deteriorating short and long term effects resulting from these type of injuries. Decreasing these rates, on a larger scale, will require more than just changing one single reactant variable of the concussion equation; it will require a collective effort from different groups of people that are all interacting with the players. I am suggesting four main actions: well-trained and knowledgeable medical staff, players that are well-informed on the risks and symptoms of concussions, better technical skills in giving and taking hits, and good equipment. Well-trained medical staff on concussive injuries will decrease the rate of players returning to the field too early and risking to worsen their injury and allow better recognition of concussive symptoms. More informed players will make more conscious players, as seen in Alan Pelc’s situation. After being exposed to and tutored about the risks, Pelc was willing to change his behavior in order to save himself many future potential problems and injuries. Better technical tackling techniques, as discussed previously, will naturally decrease the rate of concussive brain injuries by decreasing the number of potential dangerous impacts. Finally, good equipment, such as proper sized and fitted helmets, mouthguards, and HIT sensors in helmets, will allow players to be well protected and lower their chances of being exposed to injuries.
As discussed in this paper, concussive injuries can be very dangerous, impacting players for the rest of their lives. Decreasing the rates of these injuries in order to make sure that football players stay healthy — at any level — is crucial. As argued throughout this essay, changing players’ behavior with the use of innovative technologies and well trained coaching and medical staff, providing good equipment to players, and increasing their awareness with regards to the risks of concussive injuries and their short and long term effects will help football programs decrease the overall rates of these dangerous brain injuries. Recent research, such as the one currently on going here at UNC, are trying to gather more and more data from practices and games about the impacts that players are taking. In addition to the work done on this campus, experts are starting to work with local high-school programs, here in Chapel Hill, by sending internships and technological tools, to help them better prevent concussive injuries and show players that concussions are serious concerns. Furthermore researchers have also been extending their work to other contact sports such as hockey and lacrosse, which is very exciting. Even though we cannot prevent all the injuries that occur on the field, our duty is to do everything in our power to protect our players from a life-changing collision. It only takes one.
(Property of Dr. Kevin Guskiewicz)
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 Brainstem herniation is a situation when the brain tissues, cerebrospinal fluid, and blood vessels are moved or pressed away from their usual position inside the skull (the brainstem).