Jan 29, 2015What Happens Next?
In most contact sports, concussion risk comes with the territory. After the injury, safe and complete recovery depends on ample rest time–both physical and mental–followed by a gradual return-to-play protocol.
By Dr. Steven P. Broglio
Steven P. Broglio, PhD, ATC, is Director of the Neurotrauma Research Laboratory at the University of Illinois. He can be reached at: [email protected].
Every year, an estimated 1.6 to 3.8 million concussions occur as a direct result of sports and recreational activity. As the sports medicine community has learned more about this type of injury, we have become more sophisticated in our approaches to prevention and treatment. Evaluation and symptom recognition are better than ever, using powerful tools such as neurocognitive testing, balance assessments, and in some better-funded programs, high-tech instrumented football helmets that predict injuries by gauging impact force and location.
We also know more than ever about the serious consequences of ignoring a concussion or letting an athlete return to activity too soon after sustaining one. There’s still more work to do–it’s been estimated that over half of all concussions sustained by athletes in the U.S. go unreported–but this growing awareness has no doubt prevented many more serious injuries, and in some cases saved lives.
If you work with high school or college student-athletes, you must be prepared to manage the post-concussion period. And thanks to ongoing research in this area, we now understand this means much more than just holding an athlete out of competition until symptoms resolve. From their degree of physical activity in the days after a concussion to how much they mentally exert themselves while the brain heals, there are several factors that may determine the success of post-concussion recovery.
AFTER THE HIT
You’re most likely already familiar with what a concussion looks like. Following the moment of impact, the athlete may or may not lose consciousness. In fact, only 10 percent of all concussions involved a loss of consciousness. Once brought to the sideline, they can typically complete a given task, but slowed reaction times, impaired memory function, and personality changes are all common clinical signs that result from impaired neuronal signal transmission.
The full spectrum of changes that occur at the cellular level following a concussion are not fully understood, but it is thought the brain recruits pathways that bypass the injured areas to perform basic tasks and functions. Thus, reaction times may be slowed because the new pathway is simply longer or less efficient than the original. It’s sort of like highway traffic being diverted to country roads after an accident.
During the recovery process, physical healing within the brain eventually allows normal pathways to be restored–after a while the highway is cleared, and traffic can resume its usual pattern. Recovery time varies based on the severity of the injury and individual factors such as brain chemistry, but this takes an average of seven to 10 days in adults and roughly two weeks in children and adolescents. If an athlete returns to activity before fully healing, a second concussion can lead to second-impact syndrome, uncontrolled cerebral swelling, and permanent brain damage or even death.
During the healing process, there is a progression from functional brain recovery to true recovery. You might think of it like a grade one lateral ankle sprain: By one week post-injury, the athlete may be taped and sent out to practice where he can perform at a functional level, but the ligament continues to heal for some time afterward before returning to pre-injury integrity.
Functional recovery is achieved when the athlete can perform at pre-concussion levels on tests of reaction time, memory, and other basic functions. But this does not mean the neural pathways have yet been completely restored. Indeed, while functional recovery typically occurs within two weeks, true metabolic recovery from a concussion may take twice as long. What an athlete does in the post-concussive period–both physically and mentally–plays a major role in their overall outcome.
Holding an athlete out of activity following a concussion isn’t just about removing the risk of a second blow to the head, though that’s critical. Any physical exercise in the days after a concussion redirects glucose away from the healing processes occurring within the brain–it slows the restoration of neural pathways and may exacerbate symptoms. For the athlete’s health and comfort during recovery, they should be held out of not only practice and competition, but also weightroom work, physical education classes, and anything else involving physical exertion.
Why does the brain require this influx of energy? That answer is complicated, but it essentially has to do with ion imbalances generated by the injury. During the post-injury period, ions are actively moved across cell membranes in a process that requires fuel provided by glucose. This activity is accompanied by a phase of vasoconstriction in the brain, which may be a protective mechanism against cerebral bleeding. Under normal circumstances there is plenty of glucose available for optimal function of both skeletal muscles and the brain, but in the post-concussion phase, the brain must have additional glucose to maximize energy availability.
Both animal and human studies have helped us understand the negative effects of exercise on the post-concussive brain. One such investigation found that if rats were allowed to exercise immediately after a concussion, their ability to learn and remember new information was impaired when measured against rats who were withheld from exercise immediately following injury. Likewise, a study of high school football players published in 2008 noted that those who were concussed and allowed to return to the same game or practice showed the greatest declines in cognitive performance in the days after the injury.
In both these studies, the authors suggested that the cognitive impairments were a direct result of blood and glucose being directed away from the brain and thus delaying the healing process. In short, the message was that optimal recovery depends in part on the body’s ability to focus its energy on repairing the brain instead of fueling muscle activity.
Many people first heard about post-injury mental rest during the 2009 college football season, when University of Florida quarterback Tim Tebow sustained a concussion in a game against the University of Kentucky. Tebow was subsequently removed from all physical activity, had his academic load temporarily reduced, and was even instructed not to read or watch television for several days after the game in which he was injured.
The concept of resting the brain is relatively new to concussion management, so there is less data available and fewer evidence-based recommendations to rely on. The basic idea is that the cognitive demands of school work, reading, and other mentally taxing activities (those requiring attention and problem solving) pull metabolic resources away from the brain’s ion restoration process.
Think of an athlete’s typical experience after sustaining a concussion during a high school or college sporting event. They are usually held out of practice and competition until symptoms resolve, but they almost always remain in the classroom. They may even treat the time away from sports as an opportunity to bear down on school work to catch up or get ahead. Anecdotally, these athletes often report difficulty concentrating, trouble staying awake, headaches, and other symptoms that get worse throughout the day. This all appears to result from working an injured body part–the brain–without accounting for the healing that must occur.
Not all student-athletes have the same luxury as a high-profile college quarterback like Tebow, but the sports medicine staff should work with athletes and their parents and teachers to make accommodations. Part of this process is educating everyone involved about what a concussion really means: You may understand that it is a traumatic brain injury, but others might not, and some still have the outdated mentality that having one’s “bell rung” is no big deal. Once they understand the seriousness of the injury, they’re more likely to be receptive to your suggestions on mental rest.
There are no established “return to cognitive activity” guidelines for the post-concussion period. In a perfect world, you would have an athlete completely eliminate cognitive work until they are asymptomatic, but this is obviously not realistic.
A reasonable compromise is to reduce academic load as much as possible in the first few days after the injury, with an emphasis on eliminating especially demanding tasks, such as test taking, difficult reading, and mathematical problem solving. As the first week progresses, the athlete can slowly return to normal coursework. For instance, they might be limited to one to two hours of school work the first couple of days, with an additional hour added each day until their workload is back to normal.
Just like with physical recovery, the recurrence of symptoms is the best guide for whether an athlete is returning too quickly. In other words, if headaches, sleepiness, or other symptoms emerge prior to the end of the day’s mental work, the activity should be scaled back.
Not surprisingly, an athletic trainer making the case for postponing homework, reading assignments, and tests will carry more weight with teachers than athletes themselves asking for these special consideration. To reinforce the idea that this is part of an important post-injury treatment plan and not simply an impromptu vacation, you can emphasize the fact that all forms of mentally challenging activity–even the recreational ones, such as text messaging and video games–will be curtailed during this time as well. In general, the athlete should be instructed to spend as much time in a mentally relaxed state as possible.
Nothing is more important than rest after a concussion to promote the healing process and avoid disruptions that may cause discomfort and complications. But there are a few other approaches worth mentioning as part of the post-injury management discussion.
Hyperbaric chambers. Very recently, some elite athletes have experimented with the use of specially designed chambers that deliver oxygen at a pressure level higher than in the normal atmosphere. A few studies involving animals suggest that these chambers may improve metabolic activity that aids in recovery, but some scientists have speculated that the human brain and its recovery patterns are so complex that hyperbaric chambers do not help after a concussion.
Interestingly, the use of hyperbaric chambers to address the long-term effects of concussion may hold greater promise. Two recent studies found that high-pressure oxygen delivery to concussed soldiers well after their injury–three years in one case–resulted in improved cognitive functioning and sleep patterns and a marked decrease in symptoms that extended eight to nine months after the treatments ended.
It’s difficult to interpret how findings like these might apply to athletic populations. But given the mixed results of research and scholarly inquiry into the use of hyperbaric chambers, and the lack of any large-scale randomized studies focused on athletes specifically, the use of these devices does not seem prudent at this time.
Pharmacology. The use of medication in the post-concussion period can be differentiated into two distinct categories: drugs used to treat post-concussion symptoms, and those used to improve or accelerate the healing process.
In the first category, a physician may prescribe medication to control sleep disturbances or reduce headaches. This is fairly common in cases where such problems are prevalent, and it does not appear to pose significant health concerns as long as the athlete follows all physician instructions and uses the drugs only as directed.
However, one important note in using these products is that the athlete must be able to stop taking them and remain symptom-free before beginning a return-to-play protocol. A headache medication, for instance, may mask pain that indicates the brain is not yet healed, which would mean the athlete is not ready to return to workouts.
The second category includes medications such as corticosteroids, free radical scavengers such as vitamin C, glutamate receptors, calcium channel inhibitors, and drugs that affect the arachidonic acid cascade. All these have been studied to various degrees without producing consistent positive results.
The most promising pharmacological agent for boosting recovery appears to be progesterone. The exact mechanism of how this hormone may improve concussion recovery isn’t fully understood, but it is thought to decrease the post-injury inflammatory response in the brain. Progesterone treatments for concussion are entering large-scale clinical trials later this year, so we may have firmer answers on the value of this type of treatment in the near future.
Dietary adjustments. In its position statement on managing sports-related concussions, the NATA recommends that athletes limit fat intake, eat a high-carbohydrate diet, and completely abstain from alcohol consumption in the post-concussion period. There is virtually no research showing a relationship between food and drink choices and concussion recovery, but alcohol is known to impair oxygen delivery to the brain, and production of energy from fat molecules requires an abundance of oxygen. The carbohydrate recommendation was most likely added because carbs aid in the production of glucose, which may help provide the brain with needed energy for healing.
No athlete should ever be permitted to return to their sport until completing a progressive return-to-play protocol. Such a protocol should only begin once the athlete is no longer experiencing any functional deficits caused by the injury, including self-reported symptoms, physical balance issues, or cognitive impairment. At that point, the return to pre-injury activity level must be gradual.
According to a consensus statement adopted at the Third International Conference on Concussion in Sport in 2008, the newly symptom-free athlete should start with light aerobic exercise that keeps the heart rate below 70 percent of the typical max for their age. If the athlete can complete this step without a return of any concussion symptoms, light sport-specific exercise can begin a day later.
As a next step, the athlete can advance to more stressful non-contact work, such as running pass routes, walk-throughs of planned plays, and resistance training. At this point, a physician should re-evaluate the athlete before final clearance to participate in contact drills, full training, and finally, competition.
Each step in this process should take roughly one full day. If even minor concussion-related symptoms re-emerge, the athlete must return to the previous stage following 24 hours of rest. Using this strategy, depending on the age of the athlete and the severity of the injury, most will be cleared for a return to competition in one to two weeks.
Concussion remains one of the most difficult and complex challenges faced by sports medicine personnel. Injury to the brain doesn’t produce easily visible or tangible symptoms, and relying only on athletes’ own assessment of their readiness to return is not acceptable.
Ultimately, each concussed athlete must be managed individually, and it’s impossible to predict how long recovery will take. But with a comprehensive plan that focuses on both physical and mental rest and provides for a gradual return to activity, you can help any concussed athlete return to their sport safely and ready to perform at their best.
To view full references for this article, go to: www.Training-Conditioning.com/References. FEEDBACK:
When i am rehabing an athlete post injury something that needs to be watched is heart rate and subsequent blood pressure. With the hr elevation comes bp elevation which for post concussion can cause “relapse”. When starting the athlete back i put them on tread bike etc (a controlled area) and start the athlete at only 40-50% of target heart rate for 5-10min—-if this goes well then start a progression of increased time first then increased hr— with every increase in hr the exercise time is decreased and then ramped back up. When the athlete can go 45 min at 80% of their thr then they are ready to resume sport. During this time i also really curtail any weight lifting for same reason. The only thing I allow is very slow stretching in a dim to dark cool room— nothing that would increase the bp like a warm room etc.
– Andy Matthews Snoqualmie, Wash.