Authors: Marcos A. Abreu*(1), Wirt Edwards(2), Brandon D. Spradley(2)
(1) Doctoral student at the United States Sports Academy studying sports management.
(2) Professors at the United States Sports Academy
United States Sports Academy
One Academy Drive
Daphne, Alabama 36526
The game of football, especially at the higher levels, is becoming increasingly dangerous as athletes keep getting bigger, faster, and stronger. The rate at which concussions are occurring is alarming and player safety has become the topic of conversation among sport the community. Since the symptoms and signs of a concussion don’t always appear immediately or appear to be mild at first, the sports community originally assumed that the head injuries weren’t serious. Besides the risk of suffering another concussion, a growing body of research has linked sports concussions with serious long-term effects like depression and memory problems.
To make matters worse, researchers documented that high school and collegiate athletes do not report concussions sustained during football play because they were not aware of the signs and symptoms of a concussion. Furthermore, although the National Football League (NFL) injury report has shown a decrease of head injuries since 2012, PBS FRONTLINE’s Concussion Watch project reported that one-third of all concussions sustained during that time were left off the injury report. As research continues to expose the serious nature of sports concussion, league officials are facing constant scrutiny to change the rules and regulations that govern the game of football.
Although the sport of football has a protocol to assess a player for a concussion, visual inspections could limit the amount of information a health care provider could gather. To address these certain limitations, manufacturers designed football helmets to decrease the forces of impact and engineered technological solutions to better detect head impacts that may cause injury. The purpose of this study is to examine the advancements in concussion detection and prevention, ultimately, providing league officials with recommendations that could help reduce a player’s risk of a concussion. In addition to increasing concussion awareness, this study will support the balance between the adjustment to new concussion research and the sharing of knowledge acquired through research.
Keywords: concussion, concussion evaluation, concussion management, return-to-play, concussion prevention technology, football helmet concussion reducing design.
The rate at which concussions are occurring is alarming and player safety has become the topic of conversation among the sports community. The American Medical Society for Sports Medicine Concussions defined a concussion, which is a subset of mild traumatic brain injury (MTBI), “as a traumatically induced transient disturbance of brain function and involves a complex pathophysiological process (15, p. 15).” Published research in the American Family Physician by Scorza, et al. (2012) documented that a concussion is a “functional rather than structural injury that results from shear stress to brain tissue caused by rotational or angular forces—direct impact to the head is not required (36, p. 123).”
The Sports Concussion Institute reported that during direct or linear impact to the head cause the brain to strike the inner skull (i.e., the coup) when the head accelerates and the opposite side of the inner skull (i.e., the contrecoup) when the head decelerates and stops motion (37). During indirect or rotational impact to the head, the institute reported rapid head rotation from one side to another that causes shearing and straining of brain tissues. Clinical professor of neurosurgery at Boston University School of Medicine, Dr. Robert Cantu noted that “most hits are off center and because our heads are not square, most of the accelerations in the head are going to be rotational (9, p. 53).”
The American Academy of Neurology discovered that athletes are at greatest risk of repeat injury in the first 10 days post-concussion and suggested that the more head injuries a person suffers; the more likely they are to face complications later in life (12). These facts are alarming since researchers estimated that 53% of high school athletes have sustained a concussion before participation in high school sports, and 36% of collegiate athletes have a history of multiple concussions (37).” To make matters worse, Cournoyer & Tripp (2014) reported that the high school football players they surveyed did not have appropriate knowledge of the symptoms and consequences of concussions (7).
The National Athletic Trainers’ Association also reported that over 50% of high school athletes and 70% of collegiate athletes did not report concussions sustained during football because they were not aware of the signs and symptoms of a concussion (3). The lack of knowledge could also be observed at the professional levels of football. Although the data from PBS FRONTLINE’s concussion watch project, which has been tracking the head injuries from the National Football League (NFL) injury report since 2012, demonstrated a decrease in player concussions (10), one-third of all concussions sustained during that time were left off the injury report (2).
Although the sport of football has a protocol to assess a player for a concussion, visual inspections could limit the amount of information a health care provider could gather. To address these certain limitations, new technology has been developed to better monitor a player’s exposure to contact and new football helmets designed to significantly decrease the liner and rotational forces that produce concussions. The purpose of this qualitative research is to examine the advancements in concussion detection and prevention, ultimately, providing league officials with recommendations that could help reduce a player’s risk of a concussion.
REVIEW OF LITERATURE
Concussion Symptoms & Signs
Accurate assessment of concussion symptoms, signs, and their duration is important in determining the severity of the injury (15). Research published in the American Family Physician identified emotional, cognitive, sleep and physical as the categories associated with symptoms of concussions (36). According to the guidelines from the American Academy of Neurology, the concussion symptoms normally communicated by the athlete to health care professional include blurry vision, confusion, feeling hazy, drowsiness, sleep problems, headache, inability to focus, sensitivity to light, sensitivity to sound, and dizziness (10).
Giza, et al. (2013) also documented behavior or personality changes, dazed look, balance and coordination changes, delayed responses, disorientation, and unclear speech when the concussion signs are normally observed by health professionals about the athlete (12). Even if an athlete hasn’t suffered an obvious concussion, after a head collision, Director of the Mount Sinai Center for Cognitive Health and NFL Neurological Center, Dr. Sam Gandy noted that the brain’s frontal lobe is damaged and that “damage to the frontal lobe can compromise the inhibiting effect, and cause mood swings, even violence (11).”
In 2015, researchers from Boston University and Brigham and Women’s Hospital examined the brain imaging of 40 former NFL players between the ages of 40 and 65 who had more than 12 years of organized football experience. Half of the former NFL players started tackle football before turning 12 and the other half started after. Stamm, et al. (2015) concluded that the former NFL players who started tackle football before age 12 and suffered early exposure to repetitive head impacts during the neurodevelopmental period prior may suffer greater mood, behavioral, and cognitive impairments later in life (39).
An athlete suspected of sustaining a sports related concussion should be removed from play until a health professional determines whether a concussion has occurred (12). Before the concussion evaluation begins, “it is a good safety strategy to sequester an essential piece of playing equipment to avoid an ‘inadvertent’ return to the game (15, p. 21).” During the evaluation process, health care providers must use a standardized approach to track the severity of concussion symptoms over a series of evaluations post injury (15). To diagnose an athlete with a concussion, health professional must determine a time-based association between an appropriate mechanism of injury and commencement of worsening symptoms (36).
To determine the severity of any deficits, initial sideline evaluation by health professionals should include proper observation of the athlete with particular attention paid to cognitive functions (14). The Maddocks Questions, the Standardized Assessment of Concussion, the Balance Error Scoring System, the Sport Concussion Assessment Tool 2, and the NFL Sideline Concussion Assessment Tool are often used as measures to evaluate concussion symptoms (15). With the exception of the Maddocks score, McCrory et al. (2009) recommended that “the assessment should be performed continuously until the individual’s condition is found to be stable (34, p. 355).”
In 2015, NYU Langone Medical Center research, published in the Journal of Neurotrauma, presented a new objective diagnostic tool that could be utilized to effectively detect a concussion and quantify its severity (35). According to Dr. Ellenbogen, chairman of the Department of Neurological Surgery at University of Washington Medicine and co-chair of the Head, Neck and Spine Committee of the National Football League “by tracking eye movements, they have been able to quantitatively assess the function of the brain. Their new approach will hopefully identify those patients who may be missed by basing the evaluation simply on subjective complaints (23).”
Dr. Samadani, assistant professor in the Departments of Neurosurgery, Psychiatry, Neuroscience and Physiology at NYU Langone Medical Center, mentioned that the new eye-tracking methodology could “help better diagnose concussion severity, enable testing of diagnostics and therapeutics, and help assess recovery (23).” Dr. Grady, Charles Harrison Frazier Professor and Chairman of the Department of Neurosurgery at the Perelman School of Medicine at the University of Pennsylvania, mentioned that a reliable concussion test could be important “in athletics or in military settings where individuals are highly motivated to return to activity and may minimize their symptoms (23).”
After a complete sideline assessment, if health professionals do not believe a concussion occurred and the decision is made to return the athlete to play, serial evaluation should be performed to ensure the decision was correct (15). If a player is evaluated and assessed with a concussion, while symptomatic, researchers suggested that patients should avoid physical exertions that intensify symptoms and recommended cognitive rest as part of the concussion-management plan (3). Besides physical and cognitive rest, there is no evidence that any medication is effective in treating the acute symptoms of sports concussion (15).
After a concussion, return-to-play “RTP should be individualized, gradual and progressive and should consider factors that may affect individual risk and outcome. The athlete should be free of concussion symptoms at rest as well as during and after exertion before returning to full participation. The athlete should also have a normal neurological exam including a normal cognitive and balance evaluation, ideally compared to a pre injury baseline (15, p. 23).” Once the athlete is asymptomatic, if activity results in a return of symptoms the activity should be immediately halted and restarted 24 hours later (3).
Short-Term Risks Associated with Premature Return-To-Play
The decision to return-to-play should not be taken lightly. Returning to competition prematurely may increase the likelihood that an athlete will develop post-concussion syndrome. The American Medical Society for Sports Medicine defined post-concussion syndrome as “symptoms and signs of the concussion that persist for weeks to months after the incident (15, p. 24).” Besides suffering prolonged symptoms after a concussion, “the decline of cognitive ability diminishes an athlete’s ability to respond to the demands of the sport and increases the risk of a second concussion (15, p. 24).”
In youth athletes, sustaining a second concussion before recovering from the first could result in the deadly second-impact syndrome. Johnson (2012) identified Second Impact Syndrome (SIS) as a “rare neurological condition involving catastrophic diffuse cerebral swelling and brain herniation (17, p. 181).” Researchers theorized that “reinjuring neuronal cells during a vulnerable period of ongoing instability from previous injury create a disturbance of autoregulation (44, p. 333).” Athletes who sustain SIS will pass away within 5 minutes or if the athlete survives severe impairments (17).
Long-Term Risks Associated with Concussions
One of the long-term consequences of repeated head injuries is the disease Chronic Traumatic Encephalopathy (CTE). The American Medical Society for Sports Medicine described CTE as “a neurodegenerative disease associated with repetitive brain trauma and characterized pathologically by the accumulation of protein in specific areas of the brain (15, p. 25).” The Journal of Clinical Sport Psychology noted that “the most consistent biological marker of this disease is tau protein deposition in affected areas of the brain, but most prominently in the hippocampus and mesial temporal lobe structures (34, p. 359).”
The National Institutes of Health (2013) noted that “tau is a normal brain protein that folds into tangled masses in the brain cells of patients with Alzheimer’s disease and a number of other progressive neurological disorders (20, p. 1).” Corsellis 1989 noted that “the onset of CTE is insidious, and affected individuals first notice deficits in attention, memory, and concentration leading eventually to confusion and disorientation. Over time, the condition progresses to dementia, poor judgment, irrational behavior, depression, and lack of insight. In advanced cases, Parkinsonism may develop (34, p. 356).”
Although the sport of football has a protocol to assess a player for a concussion, visual inspections could limit the amount of information a health care provider could gather. To address these certain limitations, in 2003, Simbex developed the Head Impact Telemetry (HIT) System technology. The HIT system uses a MX Encoder to measure head impacts (location, magnitude, duration, and direction) during on-field play and transmits the information recorded via wireless communication with the sidelines to provide coaches and medical staff with valuable information that can be used to identify potentially dangerous head impacts (41, p. 85).
The total number of head impacts is of interest to researchers because many suspect that an increase of head trauma could injure the brain in subtle ways. Rowson et al. (2011) noted that “this technology provides the opportunity to collect a large and unbiased dataset, since every head impact that an instrumented football player experiences would be recorded including both non injurious and concussive impacts, which can be applied to a wide array of research studies that will ultimately lead to a better understanding of the mechanisms of concussion (33, p. 13).”
Since 2003, department head of the Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences, Stefan Duma has used the HIT system to study head-to-head collisions at the youth, high school and college levels of football. In an interview with Stone Phillips, PBS reported that Professor Duma stated “the average player in this youth football from 6-to 8-years-old sustains about 107 impacts over the course of that season. And you can compare that to high school, which is about 500 and then college which is about a 1,000 a season (46).”
Advancements in Concussion Detection
Since the success of Dumas’s research with the HIT system, several manufacturers have developed similar technological solutions engineered to better detect the head impacts that may cause head injuries. In 2012, Battle Sports Science developed a helmet chin strap that instantly detects when a player has taken a severe blow to the head that may cause a head injury (36). The Impact Indicator uses a micro sensor technology called head injury criterion embedded in the chin strap to measure the force of each blow a player sustains and activates a flashing red LED to warn players, trainers and coaches of the possibility of a head injury (38).
In 2013, Riddell Inc. introduced the InSite Impact Response System. The Riddell InSite Impact Response System uses new integrated technology to monitor and record significant head impacts sustained during a football game or practice. The wireless helmet system is based on the Head Impact Telemetry System (HITS) and Sideline Response System (SRS), previous Riddell helmet technologies. Riddell Inc. Media Relations Manager, Erin Griffin pointed out that “the sensor pad is a five-zone polymer thin film installed inside a player’s helmet. The sensor is mated with custom helmet electronics that feature on-board impact processing and alert determination (18, p. 24).”
In 2013, in an attempt to resolve the concussion issue, X2 Biosystems, a Seattle based company, created a new crop of lightweight sensing technology that could better detect the acceleration of a player’s head and uses this data to determine impact severity. Working with ST Microelectronics, X2 Biosystems integrated 6-axis accelerometer and wireless protocol to develop the X-Guard, a mouth guard that allows team trainer or physician to combine the results of concussion assessment tools and the data provided by the X2 app to determine the severity of the injury (45).
X2 Biosystems also released the X-patch in 2013. Similar to the X-Guard, the X-patch is able to send impact data wirelessly to the sidelines to notifying trainer or physician in real time when they should be concerned about player safety (45). CEO of X2 Biosystems, Christoph Mack stated that “the X-Patch integrates all required functions for head-impact monitoring, analysis, and wireless data transmission in a small, inconspicuous, comfortably wearable format. Because it’s so small and lightweight, it can be attached easily and unobtrusively behind the player’s ear—athletes forget they’re wearing it within minutes (4).”
In 2014, i1 Biometrics developed the Vector Mouth Guard with ESP Chip Technology. According to Jesse Harper, CEO of i1 Biometrics, “the Vector Mouth Guard with ESP Chip Technology is engineered to reduce the guesswork so that coaches and trainers have accurate and timely data to help make proper decisions for their student athletes (16).” The ESP Chip Technology in the mouth guard measures the linear and rotational accelerations of head impacts and transmits the result to a trainer or physician on the sideline, viewable via laptop or smartphone (19).
Besides providing real time data to coaches and healthcare providers on the sidelines, the technology found in the Vector Mouth Guard could be used as a training and performance device. The data provided by the ESP Chip Technology allows trainers to “realize measureable results from performance analytics to shape training programs and individualized athlete-conditioning environments (15).” The handheld technology also allows trainers to correct and improve a player’s tackling technique in an effort to decrease career threatening injuries that are associated with a player using the crown of his helmet (19).
In 2014, the Checklight was developed by sports equipment company Reebok and electronics design company MC10. When an impact meets or exceeds a certain predetermined threshold, the lightweight mesh skullcap has a LED light suspended below the base of the helmet that flashes yellow after moderate impacts or red for severe blows (8). Isaiah Kacyvenski, Mc10’s Director of Licensing and Business development, mentioned that “its flexible design measures the impact on a wearer’s head, as opposed to the impact on a helmet, which means that the data it provides is more relevant and accurate than competing systems (13).”
Advancements in Concussion Prevention
In 2011, Stefan Dumas and his team of researchers transferred everything they learned from head impact research and created the first football helmet rating system to provide consumers with valuable data in order to make educated decisions about which helmet to purchase. The Summation of Tests for the Analysis of Risk (STAR) “is a function of several variables: helmet location (front, top, combined sides, and rear), drop height ranging up to 60 inches, exposure as a function of drop height and the number of impacts for a given location at the drop height that a player may experience in one year, peak acceleration, and concussion injury risk as a function of peak acceleration (22, p. 4).”
During the Summation of Tests for the Analysis of Risk (STAR) impact testing process, “helmets are evaluated using 2 fundamental concepts: 1) each test is weighted based on how frequently players experience them and 2) helmets that lower head acceleration reduce concussion risk. The impact conditions and weightings are sport-specific, and inclusive of the broad range of head impacts that athletes are likely to experience (43).” The more stars equate to better protection, with five stars representing the best available football helmets to provide a reduction in concussion risk compared to football helmets with less stars (33).
In 2014, the Virginia Tech STAR Evaluation System awarded the Riddell 360, Riddell SpeedFlex, and Xenith EPIC with the highest rankings for football helmet performance in the area of concussion risk reduction (42). Although Riddell’s and Xenith’s football helmets will not prevent the risk of a concussion, their designs could significantly decrease the forces that are associated with concussion injuries. In 2011, Riddell Inc., the largest football-helmet manufacturer, incorporated NFL-funded research on head to head impacts by Bio kinetics, a Canadian research lab, to design the Concussion Reducing Technology incorporated in the 360 football helmet interior design (9).
In 2012, in response to the Bio kinetics study, to add more protection benefits, Riddell incorporated the Concussion Reducing Technology (CRT) that uses added energy-reducing material to side and front head impact areas in the interior design of the 360 football helmet (9, p. 58). The Riddell Inc. newsroom highlighted the protection advances in the design of the 360 football helmet that also includes strategically-placed hinge clips and a flexible facemask to reduce the forces from frontal impacts and an occipital lock system that helps keep the helmet firm and stable on the player’s head during contact (25).
In 2014, with the research data captured from head impact monitoring technologies, Riddell Inc. developed the SpeedFlex football helmet engineered with flex technology in the helmet’s shell and facemask, as well as composite energy materials throughout the helmet to reduce the forces that cause concussions (31). Popular Science highlighted the flexible panel at the crown of the helmet that reduces the forces from frontal impacts, the flexible facemask attached to the sides of the helmet that distributes impact forces evenly around the helmet, and the ratchet-lock chin strap attachment system that secures the helmet in place (5).
Although it’s virtually impossible to build a concussion-proof football helmet, besides evenly dispersing impact forces throughout the helmet, to further reduce the risk of a brain injury to players, Riddell seamlessly integrated the InSite Impact Response System, a wireless helmet system that is based on the same technology used to develop the Head Impact Telemetry (HIT) system, into the inner liner of the SpeedFlex football helmet to alert coaches and healthcare providers when a player has suffered a significant hit to the head that poses a risk of a concussion during on-field play (31).
In 2014, Xenith introduced the EPIC football helmet engineered with the Adaptive Head Protection System, a four integrated technologies. To provide that athlete with comfort and fit, the Fit Seeker Retention System tightens the chinstraps for dynamic helmet retention allowing the helmet to adapt to the player’s head and the FitLock system helps to keep the helmet secure during head to head collisions (29). “The shell geometry of the EPIC is also unique in that it allows for more ventilation than normal helmets, and the padding system of the helmet won’t absorb sweat, so players will be comfortable even in the heat (24).”
To provide the athlete with increased protection against rotational and linear forces that cause head injuries, Xenith’s Aware-Flow Shock Absorbers release air upon impact to act as a suspension system keeping the head secure during linear forces and the Shock Bonnet technology allows the shell of the helmet to move independently to reduce a player’s head movement during impact (29). “The shock absorbers come in different heights and are strategically placed throughout the liner of the helmet to guarantee protection in all areas of the head (24).”
The National Operating Committee on Standards for Athletic Equipment (NOCSAE)
Before the Virginia Tech rating system, the National Operating Committee on Standards for Athletic Equipment (NOCSAE), an association funded by equipment manufacturers, which in turn funds much of the research on sports-related head trauma, was the only organization who tested football helmets for safety by performing a vertical drop test (9). Although the NOCSAE supported and encouraged the scientific research being done by Virginia Tech in the very important area of concussion protection, the organization released several statements that criticized the Virginia Tech STAR rating system for its limitations (26, 30).
Later that year, the NOCSAE also released a statement regarding equipment certified to NOCSAE standards and voiding of certification for helmets to which third-party after-market products have been attached (27). In 2014, after the industry-funded group faced criticism of their own for failing to develop a proper helmet safety standard to avoid liability (8), the NOCSAE revised the helmet safety standard to include an evaluation of a helmet’s performance under a combination of the rotational and linear forces that are associated with concussion type injuries (28).
Furthermore, in 2015, after third-party manufacturers, particularly those who make lightweight impact sensors, the NOCSAE changed their stance regarding voiding of certification for helmets to which add-on helmet products have been attached. The new NOCSAE position allows for companies which make add-on products for football helmets to make their own certification of compliance with the NOCSAE standards on a helmet model, as long as the certification is done according to NOCSAE standards, and as long as the manufacturer assumes responsibility (in other words, potential legal liability) for the helmet/add-on combination (32).
The harsh reality is that the risk of a concussion in football will never completely be eliminated. Until the NOCSAE is independently funded and governed without bias, the safety of today’s football players will depend on league officials and their ability to implement solutions that help to decrease the risk of a player suffering a concussion. Although concussions continue to be a topic of conversation, very little is being done to ensure that players understand the information regarding concussions.
To reduce the risk of head injuries like concussions, league officials should focus on increasing concussion awareness. Adequate knowledge can help athletes better recognize the signs or symptoms of a concussion and understand the consequences of not reporting the head injury. Furthermore, league officials should require each team to have a concussion management plan that details when a player should be removed from practice or competition, give team physicians guidelines for evaluation before returning to play, and ultimately specify that if an athlete shows signs of a concussion they should never be allowed to return to play (21).
To decrease the risk of a concussion at the youth and high school levels of football, league officials should ensure that all league coaches are committed to teaching proper tackling techniques by participating in the USA Football’s Heads Up Football Program. According to a study by the Datalys Center for Sports Injury Research and Prevention, football leagues with Heads Up Football Program certified coaches have seen a decrease in football-related injuries and a decrease in concussions among their players, compared with non-Heads Up leagues (1).
Since there is no football helmet on the market that could prevent concussions, league officials should work with team equipment managers to ensure that when selecting a football helmet players are inspecting and evaluating the helmet for proper fit. The Consumer Product Safety Commission recommended that the helmet should fit comfortably around the head without slanting back over the top of the head or drawn too low over the forehead and that the chin straps securely holds the helmet in place when a player runs or during impact (6).
Ultimately, to make the game of football safer for players, league officials should consider implementing new product advancements that could help better detect and prevent a player from suffering a concussion. Besides implementing the new objective diagnostic tool by the NYU Langone Medical Center in New York City that tracks eye movements to quantitatively assess the function of the brain after a head-to-head collision, league implementation of new football helmets designed to decrease the forces associated with head impact and technological solutions engineered to better detect head impacts that may cause injury will be crucial in the battle against concussions.
APPLICATION TO SPORT
In addition to increasing concussion awareness, this review paper will support the balance between the adjustment to new concussion research and the sharing of knowledge acquired through research.
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