Concussion Prevention Strategies

Original Editor - Puja Gaikwad

Top Contributors - Puja Gaikwad and Kim Jackson  

Introduction

Sports-related concussion.jpg

Sport-related concussion is among the most frequently reported injuries in sport and recreation. A sport-related concussion (SRC) is “a traumatic brain injury induced by biomechanical forces. When it comes to concussions and traumatic brain injury, prevention truly is the key to maintaining optimal brain health. It remains the best point of intervention as it can be difficult to repair and reverse any brain damage incurred from those incidents, not to mention the increased susceptibility to secondary injuries. Prevention is necessary to reduce the number of concussions per year, and awareness is the key to prevention and raising awareness can save lives. While it is impossible to eliminate all concussions in sport, but concussion-prevention strategies can reduce the number and severity of concussions in many sports.[1] Not everything is entirely avoidable, but taking precautionary steps towards safety in all aspects is the surest way to make improvements.

Risk Factors

The reduction in the risk of concussions in youth and across all sporting populations is possible that is because Sport-related concussions are predictable and preventable. A clear understanding of probably modifiable risk factors is required to design, implement, and evaluate appropriate prevention interventions to reduce the risk of SRC. Additionally, psychological and sociocultural factors in sport play a role within the uptake of any injury-prevention strategy and need consideration.

The risk factors of concussion can be categorized as intrinsic (internal factors specific to the individual) or extrinsic (external factors associated with the environment or sport). Early recognition of these factors is a part of an individualized, patient-centered approach to the prevention of concussion.

Intrinsic Risk Factors

Intrinsic risk factors could also be modifiable (e.g.neuromuscular or sensorimotor control) or nonmodifiable (e.g. the previous history of concussion, sex, age, and genetics). A previous history of concussion may be a risk factor for future concussions.[1] The mechanism by which this happens isn't yet well understood and should be associated with genetics, epigenetics, sensorimotor or neuromuscular control, and other factors.

The research is inconsistent regarding sex as a risk factor for concussion. In sports with similar rules, women could also be at greater risk of concussion than men.[1] The risk may differ due to physical characteristics or because women may be more likely to report symptoms. As the age group increases through adolescence, the risk of concussion increases, before declining in the early twenties.

The strategy of sport-specific techniques and player skills and can also influence the risk of concussions. In elite rugby, most concussions occur to the tackler, and therefore the risk of concussion increases when the tackler accelerates travels at a high speed and has head contact.

Extrinsic Risk Factors

The environment during which an athlete play includes factors that will influence the probability of concussion, many of which can be modifiable. Contact and collision sports, like rugby, American football, and hockey, have the highest reported incidence of concussion. In youth ice hockey leagues where bodychecking is permitted. [2] There’s approximately a 4-fold increase in the risk of concussion in the 11- to 12-year age group. Gameplay has a higher concussion risk than practice.[1]

Model of Injury Prevention

Translating Research into Injury Prevention Practice framework, or TRIPP model adopts a six-staged approach which will lead to real-world injury prevention gains.[3] These stages are as follows:

  1. Injury surveillance
  2. Establish etiology and mechanism of injury
  3. Develop preventive measures
  4. Scientific evaluation (ideal Condition)
  5. Describe Intervention context to inform implementation strategies
  6. Evaluate the effectiveness of preventive measures in the implementation context.[3]

Continuum of Prevention

Prevention is of critical importance. ACA recommends the following steps to prevent concussion:

  • Primary prevention
  • Secondary prevention
  • Tertiary prevention

Primary Prevention

Primary prevention strategies target healthy individuals who are participating in sport or recreational activities. Interventions aimed towards primary prevention have shown significant changes in decreasing the risk of concussion. Recent literature into strategies for primary concussion prevention focuses on protective gear, proper technique, neck strengthening, rule changes, and education, especially in contact sports that pose the greatest SRC risk to players, such as football, hockey, soccer, and rugby.[4]

To reduce the incidence, severity, and negative health effects of concussions among players it should incorporate the following protocols and recommendations [5]:

  • Increasing awareness of concussion risks from sports and recreation.
  • Educating communities on the causes, signs, and symptoms of concussions, safe concussion management, concussion modifiers, and how to best protect themselves from injury.
  • Recommend the free, online, and tailored education and training resources available through CDC’s Heads Up concussion prevention toolkits.[6]
  • Education should target a broad range of stakeholders (e.g. athletes, parents, coaches, school administrators, athletic directors, teachers, athletic trainers, physicians, and other health care providers).[7]
  • Education should target a broad range of stakeholders (e.g. athletes, parents, coaches, school administrators, athletic directors, teachers, athletic trainers, physicians, and other health care providers).
  • Coaching safe, sports-specific skills and banning or limiting the use of certain drills or techniques is also an essential element for reducing the risk of injuries.[8]
  • All equipment used should meet national guidelines and should be used for the purpose-designed.
  • whenever playing or practicing ensure players wear helmets that are in good condition and fits well.
  • Educate players about the correct way to prevent blows to the helmet.
  • Additional example evaluating equipment recommendations related to helmet including items such as chin strap fit, the position of the helmet on the head, as well as the condition of the helmet.
  • The Player’s equipment should be fit by a professional who knows the standards for the specific equipment they are wearing. Every brand has different recommendations for fitting and those should be followed to make sure the safety of the player.[9]
  • Changing rules to better promote safety.
  • Promoting fair play policies (expect, model, and reinforce safe and fair play).[10]
  • Forbid dangerous tackles and players flying in or diving recklessly into rucks.
  • Improve and practice only on safe and effective tackling techniques.
  • The good tackling technique takes time to get perfect; regular practicing of safe and effective tackling techniques should therefore initiate at a young age in order that it eventually becomes instinctive.
  • It is additionally important to sometimes practice tackling under fatigued conditions to introduce safer tackling techniques under these circumstances.
  • Practice and safe rucking techniques, practices, and principles should be performed under the guidance of the coach especially for those players already in the ruck. These players are potentially more susceptible and exposed to concussions than the players entering the ruck.

Secondary Prevention

The secondary prevention strategy is equally important to avoid further concussions during a play that has already suffered a concussive head injury. That's the reason why “Recognising and Removing” is so essential for player well‐being.[1]

It targets early diagnosis and prevention of concussion recurrence through Pre-injury assessment. Athletes who are concussed often have mild or variable symptoms which will be difficult to spot or define. As a result, it is useful to possess some objective, pre-injury data to use as a point of comparison. Pre-season baseline tests can help identify subtle impairment and may help a clinician make individualized return-to-play decisions (by comparing with pre-injury results). The results of those tests should be used to support team doctors in their decision-making process.

From a secondary prevention perspective, the goal behind the implementation of concussion management protocols (including early detection and standardized initial management through recovery) is to reduce the risk of early recurrence of concussion after allowing athletes to resume activities at risk of concussion, such as contact sports.[11]

Secondary prevention strategies after a concussion includes:

  • Increasing awareness of concussion signs and symptoms.
  • Promoting how to recognize suspected concussions.
  • Responding quickly and appropriately to suspected TBIs, including removing the athlete from play, never returning to play the same day, and returning to play only after being evaluated and ruled out by a health care provider trained in TBI diagnosis and management.[12]
  • Following recommendations for physical, cognitive, and emotional rest in concussion management protocols to allow for gradual Return to Play and Return to Learn to promote full recovery.[11][13]

Tertiary Prevention

In the context of tertiary prevention, It focuses on rehabilitation strategies to prevent longer-term consequences of concussion. From a public health perspective, although primary prevention of concussion in youth sports aims to decrease the incidence of concussion, it’s also vital to think about the secondary and tertiary intervention strategies that include a variety of targets for reducing the risk and consequences of concussion injury.[1]

Prevention Strategies

There have been numerous methods that have been proven to be effective in preventing the risk of concussion. They are as follows:

Education

Unfortunately, concussions are not a completely preventable injury. Educating stakeholders involved in an athlete's care is a very essential step in the prevention of concussions. Concussion prevention can be implemented by educating those involved with sports, teaching proper sports techniques, and implementing the most current recommendations. Through education, people may be better able to identify the signs and symptoms involved with a concussion. Through early detection and the use of concussion baseline testing, more serious injuries could also be prevented which may be the result of returning to play too soon.[14]

Rule Changes

The next component of the Injury Reduction Plan is that the enforcement of rules changes aimed towards eliminating potentially risky behavior that could lead to injuries. Through these important changes, the NFL is leveraging data in an attempt to enhance player safety and evolve the sport. This information is driving important on-field changes, like the new lowering the head rule, and also taking guidance from coaches and team personnel about how we teach and coach these different techniques of play throughout the offseason, the league is working in a team with players, coaches, officials, medical personnel, media, and fans to communicate and educate about the new rules.[15]

It appears that rule changes are an effective way to limit the risk of concussion in sports. Some recent studies have shown that rule changes and limiting contact in practice may result in lowering head impacts.[16][17]

Fair play – Observational studies of youth and high school sports show that adherence to the rules of the sport and encouragement of fair play is related to decreased injuries, including concussions.[18] For instance, greater accelerations of the head and many concussions in sports occur during illegal play, when athletes do not anticipate the collision, or when athletes use the improper technique. Therefore, proper coaching techniques and adherence to the regulations of play may decrease the overall incidence of concussion.[17]

Protective Equipment

Protective equipment, as important as it is, helps to reduce the impact on the brain. Many studies have shown that these equipment do not prevent concussions but it helps in preventing other injuries Wearing the appropriate protective equipment and making sure that it is fitted properly, however, can reduce the risk of injury.[1][3][19]

  • Helmet
Protective equipment-Helmet

It helps to reduce the risk of severe Traumatic injuries, which tend to come with skull fractures, bleeding, and other structural injuries. It's the brain moving inside of the skull that actually causes a concussion, and a helmet will not prevent that from happening but it aids in preventing catastrophic injuries and also gives players a false sense of security. Many helmet manufacturers claim that their helmets reduce concussions,[20] but real-world research is limited and difficult to conduct.

  • Sensors

With the acknowledgment that concussions happen despite helmets, other researchers and manufacturers have looked to technology to alert players and coaches that a potentially concussive hit has taken place. For instance, Ridell’s InSite Smart Helmet Technology uses sensors in helmets to undertake to identify concussive impacts. The sensors send an alert when an impact exceeds a certain threshold, allowing that player to be identified and pulled for evaluation. The technology also tracks individual player’s impact trends in a database, allowing for intervention in training and technique where indicated. This approach might decrease future harmful impacts.[20]

  • Mouthguard
Mouthguard

Mouthguards should be used to prevent dental injuries, facial and skull fractures but at this time there are no mouth guards that prevent an athlete from sustaining a concussion.[9]The proposed benefits of wearing a mouthguard were that it changed the position of the jaw so that when the impact occurred, the mouth guard would reduce the force into the skull. here appears to have some evidence on the use of them as a reduction in the risk of concussion.[19] Recent evidence shows a greater than 50% reduction in the odds of concussion with mouth guard wear.[21]

  • Headgear

It has been marketed to prevent coupled mechanisms by providing additional barriers between the head and ball during impact. The use of protective headgear in play has paralleled reporting within the mainstream media on researchers who indicated that newer football helmets may reduce translational and rotational accelerations and that soccer headgear can minimize peak impact forces.[22] Most Marketing research and development have focused on attempts to enhance helmets and mouthguards, with some incorporating sensors which will monitor players for potential concussions. New products, like protective collars, are also being used to try to guard players during forceful impacts.[19]

  • Protective Collars and Compression Equipment

Some scientists have been working to create completely new protective equipment that they hope will actually prevent concussions from happening during a forceful impact. Here are a couple of recent innovations that are being tested and used.[19]

QCollar

QCollar’s inventors set out to create a product that might reduce the brain’s movement inside the skull. The QCollar is a small collar that should be worn around the neck. It applies light pressure to the jugular vein to increase blood volume in the brain. The idea is that this then reduces the amount of room available for the brain to slosh, thus possibly preventing a concussion. They report that independent studies show a significant decrease in structural brain changes in athletes who wore the collar for a season.

Neck Strengthening

Neck strengthening is the newer frontier in combatting sports-related concussions. A promising area of research in preventing concussion emphasizes on the cervical musculature's ability to reduce head impacts in addition to protecting the player from an injury to the neck itself. Many risk factors are not able to be altered, however, there have been a number of studies that have looked at the correlation between neck strength and concussion risk and found that neck strength may indeed be a modifiable risk factor.[3][23]

Tackle

It is hypothesized that concussions can occur most commonly through linear and rotational head accelerations such as whiplash.[24] That’s where strengthening the neck can be an advantage in helping to prevent concussions. Skeletal muscles not only produce force but also should absorb shock (decelerate) movements.[3] In other words, athletes with stronger neck muscles could also be able to take control of the whiplash-like movement that occurs when the body is slammed into during high-impact sports, reducing the likelihood of a concussion.

A critical piece of the concussion prevention strategy involves the training of the cervical spine to safely absorb the impacts that commonly occur in sports. This is a very complex process that requires special attention to the ligaments and connective tissue of the spine itself, appropriate levels and qualities of strength, and scientifically designed exercises that enhance the reaction speed to sudden impulsive loads.” It highly encourages those athletes that play sports most susceptible to concussion to perform neck strengthening exercises as part of warm-ups or as part of strength training workouts. Research shows a strong association between whiplash-induced injuries and concussion exists so in theory if the whiplash effect can be decreased by increasing neck and core strength it can also reduce the risk of concussion. [24]

Proper and safe cervical strengthening is of utmost importance. It involves isometric resistance training of neck flexors, extensors, lateral flexors, and rotators along with the core muscles which are important in minimizing injury risk during impacts. As an additional benefit, it's also capable of simulating functional sport-specific movements, improving reaction time, and strength training for a specific sport. Working on the neck strength before the beginning of the season is imperative. Exercises such as maintaining a bear crawl position on hands and toes whilst a therapist applies force in various directions to the head, to which you resist the head from moving, are often useful to practice regularly.

[25]

There are tools that are currently being used to measure neck strength in order to predict those at higher risk for concussions. There have been studies that looked at neck strengthening programs in athletes and found the program does improve isometric neck strength.[26]

Tackle Training Strategies

An assessment of tackle mechanisms has identified a deliberate or accidental clash of heads between players as having the highest probability of head injury. The frequency of this type of tackle is relatively low compared with other tackle mechanisms during competition. The second most common cause of head/neck injuries involved the use of an arm or hand by one player impacting another player’s head. In the Norwegian studies on head injury, the most common playing action accounting for injury was a heading duel (60% of injuries), with 41% of cases due to head contact with the elbow or hand and 32% due to head-to-head contact.[27]

Being educated on appropriate techniques in sports is additionally an important part of concussion prevention. Spearing is an alarming form of tackling that can lead to concussions and other serious injuries. Spearing is when a player tackles with their helmet in a head-down position. This produces an axial load through the head and down the spine which may cause serious injuries to the cervical spine along with a higher risk of concussions. [28] Making sure that athletes are tackling with their head up is essential to reduce injuries. Correct techniques should be taught at a young age to help ensure they perform correctly as they get older. Also, Restricting the number of collision practices in youth football may reduce the frequency of head impacts in games and practice.

All athletes need to take responsibility for preparing their bodies before the season starts from non-contact ball-handling drills and cross-training to balance and posture exercises. The more comfortable a player is with the ball, as an example, the more likely they’ll be aware of their surroundings and at lower risk of colliding with other team players as they move the ball down the field. Learning to control the body and, by extension, the ball, may translate to fewer concussions and thereby also improves sports performance.

Neuromuscular Training Warm-Ups

In one of the studies, it has shown greater than 50% reduction in concussion risk in rugby following a season including neuromuscular training warm-up strategies performed at least 3 times weekly. Preliminary evidence in youth soccer to demonstrate a similar reduction in concussion risk over 50% with the use of neuromuscular training programs. [27]

[29]

Vision Training

Vision therapy is also called as Oculomotor Therapy. It is conserved as a viable way to help prevent concussions. According to one of the research, great vision allows football players to use their eyes and brain to obtain the information in their peripheral vision allowing the athlete to react faster to their environment to avoid injury-causing collisions.[30] It emphasizes functional skills like eye-tracking, focusing, eye teaming (the way the eyes work together), hand-eye coordination, etc. Research has shown a significant reduction in the risk of concussion in collegiate football players.[30][31]

[32]

Prevention Challenges

While progress has been made in promoting, implementing, and, in some cases, evaluating the prevention strategies described above, many challenges remain, particularly in concussion knowledge and awareness, and in the culture of sports.[6]

  • Knowledge and awareness

Knowledge and awareness of concussion risk, recognition, and management are increasing but research indicates that too many young athletes still do not report their concussion symptoms, are not removed from play and continue to play with symptoms, or return to play too soon. Young athletes and their parents may not be familiar with concussion signs and symptoms, nor with state concussion laws or school or league protocols guiding when a player can return to learn and/or play. Also, coaches may not be able to recognize the more subtle signs of a concussion, nor understand the importance of managing both athletic and cognitive activities following a concussion.

  • Sports Culture

The concussion-related views and actions of a young athlete are influenced by a “sports culture” that is created and influenced by parents, coaches, teammates, spectators, and the athletes themselves. This culture is created in part by how parents and coaches talk about what is acceptable or unacceptable for the team, and how to follow safe play and rules of the sport. This culture influences concussion reporting and management by both the athlete and the coach. When young athletes receive positive messages about reporting a concussion from their coach, they are more likely to report concussion symptoms correctly.[6]

Conclusion

It is difficult to manage the risk of concussion in high paced, hard-hitting, strong contact sport, and research is still ongoing with regards to the benefits of external aids to help minimize the impact or severity of such an injury. Adequate conditioning, all‐year-round neck strengthening, good tackle, and ruck techniques, abiding by the laws of the game, appropriate use of equipment, and a concussion policy that players, coaches, referees, and supporters understand, will significantly help reduce the risks. [33] protective equipment, such as helmets, headgear, and mouthguards, may eliminate the risk of concussion but the literature is inconclusive. Researchers and manufacturers are working to improve or transform existing equipment to reduce the number of concussions in various sports.

Prevention strategies for concussion got to be based on knowledge of the mechanisms of injury. Most concussions occurred through body contact with other players or during tackling. Therefore, primary prevention strategies that focus on specializing in targeting body-contact/tackling skills and improved secondary prevention measures concerning compliance with return-to-play protocols would be valuable. [34]

References

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