A concussion is a brain injury resulting in temporary loss of normal brain function. Medically, concussions are a clinical syndrome characterized by immediate and transient alteration in brain function. This includes alteration of mental status or level of consciousness, which results from mechanical force or trauma.
Concussions may be caused by direct trauma to the head, such as from falling, getting hit, or being in an accident. They may also occur as a result of rapid acceleration-deceleration of the head, as seen in whiplash injuries or blast injuries created in a war zone. Many people assume that concussions involve passing out or a loss of consciousness, but this is not true. Often, people with a concussion never lose consciousness. In most instances, external signs of head trauma like bleeding may also be absent.
A concussion may affect speech, balance, memory, judgment, reflexes, and muscle coordination. People with concussions often report a brief period of amnesia or forgetfulness, in which they struggle to remember what happened immediately before or after the injury. They may act confused, dazed or describe “seeing stars.” Paramedics and athletic trainers who suspect a person has suffered a concussion may ask the injured person if they know their name, what month/year it is, and where they are.
Even mild concussions should not be taken lightly. Neurosurgeons and other brain injury experts emphasize that although some concussions are less serious than others, minor concussions do not exist. In most cases, a single concussion should not cause permanent damage. A second concussion soon after the first one does not have to be very strong for its effects to be permanently disabling.
Common Symptoms of Concussion
- Dizziness or imbalance
- Nausea or vomiting
- Vision disturbances (double or blurry vision)
- Sensitivity to light
- Loss of smell or taste
- Trouble falling asleep
- Memory loss
- Ringing ears
- Difficulty concentrating
If any of these occur after a blow to the head, a health-care professional should be consulted as soon as possible.
WHEN TO SEEK MEDICAL CARE
Most people will recover quickly and completely. Some people may have symptoms that last for several weeks before getting better.
Seek immediate medical attention if:
- Headache is worse or does not go away
- Inability to wake up
- Loss of consciousness
- History of multiple concussions
- Symptoms have worsened at any time
- Symptoms have not gone away after 10-14 days
- Slurred speech, weakness, numbness or decreased coordination
- Significant nausea or repeated vomiting
TESTING AND DIAGNOSIS
Brain imaging studies with MRI and CT scans should not be performed routinely for the diagnosis of concussions. They typically do not show any significant changes, and CT scans expose individuals to unneeded radiation. While these tests are more useful for identifying structural defects, an injury from concussion is metabolic and microscopic in nature that often presents normally on neuroimaging.
The doctor asks a variety of questions about how the injury occurred and where on the head, as well as what symptoms are shown. The patient should report any unusual experiences to the health care provider.
PREVALENCE AND INCIDENCE
According to the Centers for Disease Control and Prevention (CDC) surveillance report of traumatic brain injuries, about 2.87 million TBI-related ED visits, hospitalizations, and deaths occurred in the United States during 2014. Each year, over 800,000 children are treated for TBI at emergency departments in the US. The highest incidence of TBI occurred in people aged 75+, children aged 0-4, and those aged 15-24 years.
University of Pittsburgh's Brain Trauma Research Center reports more than 300,000 sports-related concussions occur annually in the US. Additionally, the likelihood of suffering a concussion while playing a contact sport is estimated to be up to 19% per year of play. Thus, almost all athletes of contact sports suffer from a concussion within five years of participation. Over 62,000 concussions are sustained each year in high school contact sports. Among college football players, 34% have had one concussion, while 20% have endured multiple concussions. Estimates show that 4-20% of college and high school football players sustain a brain injury over the course of one season. The risk of concussion in football is 3-6x times higher in players with previous concussions.
A study conducted by McGill University found that 60% of college soccer players reported symptoms of a concussion at least once during the season. It also showed that concussion rates in soccer players were comparable to the rates in football. According to this study, athletes who suffered a concussion were 4-6x more likely to suffer a second. Research such as this has led to greater interest in developing protective headgear for soccer participants, but it is not clear that such headgear actually reduces the risk of concussion.
Concussion symptoms affect people in a variety of ways, including balance, vision, and even mood. Historically, the standard treatment for concussion was to receive plenty of rest. However, newer approaches involve therapy to target specific symptoms. Clinics exist that help determine the most affected system and appropriate therapy for a given symptomatology. Also, a thorough medical examination may be needed before returning to sports or activities with the potential for contact or further head injury.
After a concussion, certain people may suffer persisting symptoms like memory and concentration problems, mood swings, personality changes, headache, fatigue, dizziness, insomnia, and excessive drowsiness throughout following weeks or months (post-concussive syndrome). Patients with post-concussive syndrome should avoid activities that risk a repeated concussion. Athletes should not return to play while experiencing these symptoms. Athletes who suffer repeated concussions should consider terminating participation in the sport.
Second impact syndrome results from acute and often fatal brain swelling that occurs when a second concussion is sustained before complete recovery from a previous concussion. The impact is believed to cause vascular congestion and increased intracranial pressure, which may occur very rapidly, being difficult or impossible to control. The risk of second-impact syndrome is higher in sports like boxing, football, ice, or roller hockey, soccer, baseball, basketball and skiing. The CDC reports an average of 1.5 deaths per year from sports concussions. In most cases, a concussion, usually undiagnosed, had occurred prior to the final one.
HEAD INJURY PREVENTION TIPS
Buy and use helmets or protective headgear approved by the American Society for Testing and Materials (ASTM) for specific sports 100% of the time. The ASTM has vigorous standards for testing helmets for many sports; helmets approved by the ASTM bear a sticker stating this. Helmets and headgear can be purchased in numerous sizes and styles, but they must properly fit to provide maximum protection against head injuries.
In addition to other safety apparel or gear, helmets or headgear should be worn at all times for:
- Baseball and softball (when batting)
- Horseback riding
- Powered recreational vehicles
Headgear is recommended by many sports safety experts for:
- Martial arts
- Pole vaulting
- Do not dive in water less than nine feet deep or in above-ground pools.
- Follow all rules at water parks and swimming pools.
- Wear appropriate clothing for the sport.
- Do not wear any clothing that may interfere with vision.
- Obey all traffic signals, and be aware of drivers when cycling or skateboarding.
- Avoid uneven or unpaved surfaces when cycling or skateboarding.
- Supervise younger children at all times, and do not let them use sporting equipment or play sports unsuitable for their age.
- Do not participate in sports when ill or very tired.
- Perform regular safety checks of sports fields, playgrounds and equipment.
- Discard and replace sporting equipment or protective gear that is damaged.
- Remove hazards in the home that may contribute to falls. Secure rugs and loose electrical cords, put away toys, use safety gates and install window guards. Install grab bars and handrails for the frail or elderly.
- Never drive while under the influence of drugs or alcohol, or ride as a passenger with anybody who is under the influence.
- Wear a seat belt every time, whether driving or riding in a motor vehicle.
- Keep unloaded firearms in a locked cabinet or safe, and store ammunition in a separate, secure location.
CONCUSSIONS AND HEAD INJURIES
The skull protects the brain against penetrating trauma, but it does not absorb all the impact of a violent force. The brain is cushioned inside the skull by the surrounding cerebrospinal fluid, but an abrupt blow to the head (even a rapid deceleration) may inspire the brain to contact the inner side of the skull. This holds the potential for tearing of blood vessels, pulling of nerve fibers, and bruising of the brain.
Sometimes the blow may result in microscopic damage to the brain cells, failing to enact obvious structural damage visible on a CT scan. For extreme cases, the brain tissue may begin to swell. Since the brain cannot escape the skull's rigid confines, severe swelling may compress the brain and its blood vessels, limiting blood flow. Lacking adequate blood flow, the brain does not receive the necessary flow of oxygen and glucose. A stroke may happen. Brain swelling after a concussion has the potential to amplify the injury’s severity.
A blow to the head may cause a more serious initial injury to the brain. A contusion is a bruise of the brain tissue, involving the bleeding and swelling of the head. A skull fracture occurs when the bone of the skull breaks. By itself, a skull fracture might not necessarily be a serious injury. Sometimes, however, the broken skull bones cause bleeding or other damage by cutting into the brain or its coverings.
A hematoma is a blood clot. It collects in or around the area of the brain. If active bleeding persists, hematomas may rapidly enlarge. Like brain swelling, the increasing pressure within the rigid confines of the skull (due to an enlarging blood clot) may cause severe neurological problems and may even be life-threatening. Some hematomas are surgical emergencies. Hematomas that are small may sometimes go undetected initially, but may cause symptoms and require treatment several days or weeks later.
Warning Signs of a Serious Brain Injury
- Speech: Difficulty finding the "right" word; difficulty expressing words or thoughts; dysarthric speech
- Motor dysfunction: Inability to control or coordinate motor functions or disturbance to balance
- Sensory: Changes in ability to hear, taste or see; dizziness; hypersensitivity to light or soundPain: Constant/recurring headache
- Cognitive: Shortened attention span; easily distracted; overstimulated by environment; difficulty staying focused on a task, following directions or understanding information; feeling of disorientation, confusion and other neuropsychological deficiencies
Seek immediate medical attention if any of these warning signs occur
MANAGING CONCUSSIONS: THE NFL PROTOCOL
No set timeframe for recovery and return to participation exists under the NFL’s current guidelines. Ultimately, the decision to return a concussed player back to practice and games resides with the team physician managing the concussion protocols and is confirmed by an independent neurological consultant (INC), who is consulted specifically for the player’s neurological health.
Following the diagnosis of a player with a concussion, a minimum of daily monitoring must be maintained. The player’s past concussion exposure, family history, and medical history are considered, formulating a more complete picture of his health. The protocol progresses through a series of steps, moving to the next step only when all activities in the current step are tolerated without recurrence of symptoms. Communication between the player and the medical staff during the protocol is essential.
First, a patient must rest. In addition to avoiding exertion, the player must avoid electronics, social media, and even team meetings until returning to their baseline symptoms/sign levels. The next step introduces light aerobic exercise under the team’s medical staff. If aerobics are tolerated, the team physician will reintroduce strength training. The fourth step includes some non-contact football-specific activities. Lastly, the fifth step, clearance to resume full football activity, occurs if neurocognitive testing remains at baseline and there is no recurrence of signs or symptoms of a concussion.
When the team physician gives the player final clearance, the player has a final examination by the INC assigned to his team. The INC will review all reports and tests documented through the player’s recovery. Once the INC confirms the conclusion of the team physician, the player is considered cleared and is eligible for the next game or practice.
This allows for players to heal at their own individual rates. It also includes the expertise of both the team physicians and a neurological consultant, along with an assessment of not only the most recent concussion, but also the consideration of the player’s medical history.
NCAA CONCUSSION UPDATE
The National Collegiate Athletic Association (NCAA) 2011-2012 Sports Medicine Handbook includes a section called "Concussion or Mild Traumatic Brain Injury (mTBI) in the Athlete":
"In the years 2004 to 2009, the rate of concussion during games per 1,000 athlete exposures for football was 3.1; for men's lacrosse, 2.6; for men's ice hockey, 2.4; for women's ice hockey, 2.2; for women's soccer, 2.2; for wrestling, 1.4; for men's soccer, 1.4; for women's lacrosse, 1.2; for field hockey, 1.2; for women's basketball, 1.2; and for men's basketball, 0.6, accounting for between four and 16.2% of the injuries for these sports, as reported by the NCAA Injury Surveillance Program by the Datalys Center."
This organization defines a concussion or mild traumatic brain injury as "a complex pathophysiological process affecting the brain, induced by traumatic biomechanical forces."
The handbook also states, "NCAA member institutions must have a concussion management plan for their student-athletes on file with specific components as described in Bylaw 188.8.131.52 (see Guideline 2i)."
The NCAA Plan
- Mandates institutions to provide a process for removing a student-athlete that exhibits signs of a concussion. Student-athletes exhibiting signs of concussions must be evaluated by a medical staff member with experience in the evaluation and management of concussions before they may return to play.
- Requires student-athletes diagnosed with a concussion be cleared by a physician or a physician's designee before they are permitted to return
- Prohibits a student-athlete with concussion symptoms from returning to play on the day of the activity.
- Requires student-athletes to receive information about the signs and symptoms of concussions. They also are required to sign a waiver that says they are responsible for reporting injuries to the medical staff..
The signs of a concussion, according to the NCAA, are as follows:
- Balance problems
- Feeling sluggish
- Concentration or memory problems
- Double or fuzzy vision
- Sensitivity to light or noise
- Slowed reaction time
- Feeling unusually irritable
- Loss of consciousness
The handbook includes much more information on concussions (this starts on page 55). The NCAA also recommends viewing the National Athletic Trainers' Association's Heads Up video, taking a deeper look at the types of head injuries incurred and how they happen.
Sports-related neurosurgical injuries were the focus of the November 2011 issue of the Journal of Neurosurgery, which included the results of a study of 451 patients about the mechanisms and repercussions of head injuries referencing an anonymous survey. This survey found that over 46% of university soccer players experienced a concussion in one fall season, and almost ⅔ of the same group experienced a concussion over the year period while playing soccer. Another article described a new smartphone app designed for on-the-field concussion testing.