The Truth about Concussions
With kids back in school and football in season on the horizon, the topic of concussions may currently be a popular concern among players and parents. There will most likely be someone you know or know of that will experience a concussion this year. Your brain is your most valuable organ in your body because it controls and coordinates all other functions within your body. Concussions increased from 300,000 in 2001 to 4 million in 2011,1,2 however, as many as 50% of concussions go unreported.3 More than 1,000,000 mild traumatic brain injuries4 and an estimated 1.6-3.8 million sport-related concussions occur every year in the United states.5 This is a huge problem that needs to be addressed and taken more seriously.
What Is a Concussion?
Concussions have a historical meaning of a low velocity injury that causes the brain to get shaken within the skull. Concussions are more of a functional problem rather than structural one.6 A Concussion is a brain injury that has a pathophysiological effect on the brain, induced by biomechanical forces6 that juggle the brain around within the skull. In the past, damage from concussions and head injuries in the sports community were minimized and often overlooked to get players back on the field as soon as possible.7Concussions result in neuroinflammation in the brain that can persist after the initial injury.8 Now, we are seeing some of the long term effects and are starting to study them more to learn more about them.
Rotational forces are most damaging to the brain because they cause more damage to the neurons themselves.8,9–13These rotational forces cause shearing within the brain and is the primary mechanism of injury during a concussion.14-16 The same amount of force that it takes to cause a whiplash injury to the neck can cause a concussion, and they are very similar in terms of mechanism of injury and often occur at the same time.
Pathophysiology of a Concussion:
When a concussion occurs, the cellular membranes of neurons are damaged and excitatory neurotransmitters are released causing misfiring of nerves and ionic imbalances occur simultaneously. The high amount of force involved with a traumatic brain injury is sufficient to damage the microtubules in axons in the brain, causing them to rupture.17 This this significant because the break in the axons interferes with transport of materials in the cells, not allowing them to function efficiently. Since cells are damaged there is an increase in uptake of ATP (energy currency of a cell) to help repair the damaged cells and balance the ionic imbalances. This also means there is an increase in glucose by the brain within 24 hours after a concussion, but is sometimes hindered getting to the brain by a decrease in cerebral blood flow from the inflammation that occurs simultaneously from the concussion. 5,18-21 The process is know as the metabolic cascade.
Loss of consciousness only occurs in 8-19% of concussions and is not a defining feature.30,36 For most people, symptoms typically resolve 80-90% within 7 days after a concussion.37,22-24,31 Unfortunately, headaches, dizziness38,39, fatigue,26,27 tiredness, fogginess24 at the time of the concussion are some symptoms that are usually associated with longer recovery times. If a concussion damages the hippocampus, amygdala, or prefrontal region of the brain, then that person may be prone to having emotional or mood problems since those areas of the brain can greatly influence them.3 Sometimes, migraines can be so bad after a concussion that light and noise can exacerbate the migraine, leaving one feeling uncomfortable and irritable. It is not uncommon for symptoms to get worse in the days following a concussion, especially with exercise or significant cognitive exertion.40 This suggests that even though someone may no longer have symptoms, their bodies may still have an underlying problem going undetected. The cervical spine can have involvement with headaches following a concussion41, especially the upper cervical spine.42,43 When the cervical spine is out of alignment it can also affect the function of the vestibular system which can play a role with dizziness and balance post concussion. A study done by Hurwitz et al found that the cervical spine was involved in all individuals who had a concussion.44 This suggests that people who have had a concussion should get their neck checked by a chiropractor to see if they have a subluxation. A chronic history of concussions increase your risk for developing neurodegenerative diseases, such as chronic traumatic encephalopathy (CTE) and dementia.45-48 In a 9 year study, retired professional football players that reported 3 or more concussions were 3 times more likely to be diagnosed with depression compared to athletes that reported no concussions.49 A study published in Nature Reviews Neurology found that a single diagnosis during the adolescence years increased your risk of developing MS by 22%, and individuals who have suffered two or more concussions increased their risk of MS by 133%!35
There is currently no gold standard test for diagnosing concussions.50 It is challenging to determine if any neurons in one’s brain have been damaged with the technology we have today, other than dissection after someone has ceased.6,51 The majority of patients with a mild traumatic brain injury will have a normal Glasgow coma scale of 15, which means we need to find other ways to quantify the damage that is being done when a concussion occurs, not just rely on the symptoms. The majority of sport related concussions do not require neuroimaging.52-57 Since a concussion represents more of a functional problem than a structural one, CT scans and MRIs are almost always negative.6,58-64 Only 5-8% of traumatic brain injury patients will have a CT-positive scan,65 but are necessary to detect skull fractures, swelling of the brain, intracranial hemorrhage, and any other anatomical pathologies that might be present or life threatening.6 Most of the time, the results are negative because there is no way to see axonal damage in the brain with imaging at this point in time.6,58-64 Hopefully, new technology will be developed in the future so we will be able to see the damage and quantify it. Athletic trainers and primary sports physicians are great at detecting these life threatening traumas. The scary part is the effects of concussions are cumulative over time66,67, especially if one has not recovered from a current concussion.19,21,68-72 This means that even if you feel fine after a concussion in the past, the damage accumulates in the brain over time if recurrent concussions are happening. Even subconcussive blows to the head can be cumulative73,74 and pathological to the brain.3,75
Only your medical doctor can determine if medication is necessary, but keep in mind that taking pharmaceuticals can mask the symptoms of a concussion. This is a great concern because if we are determining if someone has gotten better after a concussion based how they feel while taking medications, the results can be misleading.6 In some cases, it is best to avoid anti-inflammatory pain medication in order to minimize bleeding risk and cover up symptoms the concussion may be producing.40
What Type of Helmets Are Best?
Currently, there is a great market for helmets that may be able to reduce the risk of concussion. Helmets provide protection to the head by absorbing impacting forces and diffusing them over a greater surface area.76 With the recent awareness of concussions over the past decade, there have been many people trying to design special helmets to help to prevent concussions or marketing helmets with such claims. Making sure the helmet fits properly is most important so the helmet has less room to float around and possibly slide off. As of right now, there is insufficient data to support one type of football helmet over others when it comes to preventing concussions.25,77,78 However, no matter how good the helmet is, it is the abrupt outside forces that cause the brain to get shaken within the skull itself. There is no helmet that can prevent the brain from getting shaken within the skull under contact sports! Most people think just because you have a helmet on that your head is protected. This is true to some extent, because your skull is more protected from getting lacerations, fractures and bruised, but this does not prevent the brain from getting shaken within the skull and reduce your risk of concussion.25,79-82
Should you Exercise after a Concussion?
There is great debate over whether someone should exercise post concussion. Some questions that arise when this topic is brought up are; how long after a concussion should someone start to exercise? What type of intensity? What type of exercise? Does the degree of the concussion play a factor? Low-level exercise for those who are slow to recover may be beneficial, but this can vary person to person.6 One study done by Majerke et al found that performing high levels of activity after a concussion worsened neurocognitive performance.83 Physical exercise was found to have a statistically significant improvement in the post-concussion symptom scale score and symptoms in patients with a concussion.84 Monitoring your progress and trying not to push yourself during the acute stage after a concussion is important. You are the best predictor of how you are doing, so if you feel yourself getting worse then you should cut your exercises back and gradually build up.
How to Minimize Risk?
- Playing a sport, like soccer, that requires you to head the ball, it helps to properly tense the muscles of the back and neck in preparation to head the ball.7
- Neck strengthening exercises to increase stability of the cervical spine for better control of the head105,106
- Limit the number of contact practices to reduce exposures to potential concussions3
- Reducing illegal tackles such as high tackles in Rugby can reduce risk
How Can Chiropractic Help with Concussions?
When many people get a concussion, they often don’t think of going to a chiropractor for help during the recovery process. The brain is the most important organ in the body and the brain stem extends down to the first and second vertebrae in your neck. If these bones become misaligned during the whiplash/concussion, they can affect the function of the brain.
The brain needs 3 things to function:
- Energy (glucose/ketones)
Oxygen is important for the metabolic process in our cells (oxidative phosphorylation). If our spine is subluxated, affecting the nerves going to the lungs, it can decrease the function of our lungs. From a more biomechanical point of view, if our rib cage cannot move properly, then our lungs won’t be able to expand as full as they should, decreasing the amount of possible oxygen that could be getting to our cells.107 It is important to get plenty of oxygen to meet the demands of our brain.
Adjustments can increase:
1. Oxygen intake108
2. Cerebrospinal fluid flow109
3. Neurological stimulation to the brain
4. Balance to the autonomic nervous system
Often times, the upper cervical spine can get misaligned putting tension on the suboccipital muscles, especially rectus capitis posterior minor. This is directly attached to the dura matter110, which may play a role in recovery and symptomatology a person may experience after a concussion.111 The dura is also innervated by the first 3 cervical nerves, which converge with the trigeminal nerve in the trigeminal nucleus. Rotation in C1 and C2, disc herniations C4-C7, and chiari malformations have been found to decrease cerebral spinal fluid flow totally and partially to the brain found using UPRIGHTⓇ CSF flow by the FONAR UPRIGHTⓇ Multi-PositionTM MRI. This is a special type of MRI that is used to see cerebrospinal fluid moving in real time. This is huge in the research world! Decreased CSF could be a contributing factor in the recovery process after a concussion and should definitely be considered.109 Spinal adjustments can help to align the spine, improving CSF flow, making nutrients more available to the brain and spinal cord.
If there is lack of motion in the spine, then it will send less sensorimotor input into the brain. Adjustments given to areas of the spine that are not moving properly can increase neurological input, stimulating areas of the brain, giving the brain a boost.
Misalignments in the spine can cause an imbalance in the autonomic nervous system decreasing vagal tone (rest and digest mode), which is important during the healing process and overall health especially when dealing with a concussion. If the spine becomes misaligned affecting the vagus nerve or vagal tone of the body then many digestive and other health related problems can arise as a result.
How a Concussion Can Affect My Performance?
After a collegiate football player sustains a concussion, they are 2.5 times more likely to sustain a lower extremity injury or ligamentous injury than uninjured teammates.112-114 This is thought to be because of unresolved neuromuscular impairments. I would suggest that there are interferences within the nervous system coming from subluxations in the spine, or damage in specific areas of the brain, leading to neuromuscular deficits. With a decrease in neuromuscular control as a result, this means the ligamentous structures in the knees and ankles will be more stressed and be more likely to get injured as a result.115 A decrease in voluntary contraction has been demonstrated in ice hockey players116 and decrease in quadriceps strength has been demonstrated in college football players after a concussion.117 All skeletal muscles are under neurological control. If the nervous system cannot communicate properly with the muscles, then you have a loss of neuromuscular control. Adjustments can help to improve the neuromuscular control, by removing neurological interference that may be caused by subluxations in the spine.
The damaging effects from concussions have received more attention the past decade due to social media and athletes speaking out about it. Even if you do not have symptoms from a concussion, it does not mean no damage has been done and symptoms can vary from person to person. Right now, there is no definitive objective test that can be used to verify if you have had a concussion. There is no helmet on the market that can prevent a concussion from occurring, you can only minimize your risk while playing sports or extracurricular activities. Chiropractic focuses on restoring the brain and nervous system back to normal and can be a great way to help recover from a concussion!
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