P.Gunnar Brolinson, D.O.
Dan Elliott, D.O.
Virginia Tech Sports Medicine
Concussion largely remains an "invisible" injury that has no defined timeline for recovery. Even with improved technology and understanding of neuroscience, there is still no universal agreement on the definition or grading of concussion. The American Academy of Neurology defines concussion as "a trauma-induced alteration in mental status that may or may not involve loss of consciousness. Confusion and amnesia are the hallmarks of concussion." More importantly, recognition of brain injury is the key to evaluation and management.
Concussion management in athletics continues to be a challenge for both team physicians and athletic trainers. Over the past four decades, many strategies have evolved that include improved recognition, prevention, and rehabilitation of concussive episodes.
Historically there has been a decline in brain and cervical spine deaths among high school players. In 1968, brain and cervical spine injuries among high school and college football players resulted in 36 deaths. Over the past thirteen years, the rate has dropped to approximately 5 per year. There are multiple reasons for this decline including rule changes, improved equipment standards, heightened awareness by coaches, players and clinicians, and improved assessment techniques. However, there is still room for improvement.
Sports with potential for contact with other players or the ground obviously carry an increased potential for head injury. A heightened awareness at these sporting events is the first step of management. Examples of high-risk sports include boxing, football, gymnastics, ice hockey, wrestling, soccer, lacrosse, and basketball. We expect that the incidence of concussion, or mild traumatic brain injury (MTBI), will increase as the popularity of these sports increases.
The Centers for Disease Control (CDC) estimates the incidence of concussion at 300,000 cases per year. Of those, one third occurs in football. Concussion is a major source lost player time and accounts for 13.3% of all football injuries. There are approximately 62,800 cases seen in high school varsity athletes. These numbers are impressive but are likely lower than the actual occurrence as many concussions go undiagnosed or unreported.
Difficulty with diagnosis of concussion stems from the protean nature of the entity and often vague clinical symptoms. Athletes with concussion may have a vacant stare, delayed verbal and motor response, confusion, decreased ability to concentrate, disorientation, slurred speech, labile emotions, and/or loss of consciousness. It should be noted that loss of consciousness does not have to occur during a concussive episode. Players will often hide symptoms because they do not want to be removed from the game or lose playing time. Sometimes, the diagnosis is made days after the injury based on late symptoms such as headache, light-headedness, inability to focus, decline in classroom performance, easy fatigability, irritability, visual disturbances, anxiety, depression, and sleep disruption.
Functional MRI, neuropsychological testing, and color flow Doppler ultrasound are some of the cutting edge technology that has been helpful in assessing the brain's response to concussion. In addition, there are new methods for the assessment of concussion being developed presently. Virginia Tech has been involved recently in developing the Head Impact Telemetry (HIT®) System. Using monitoring devices located in the players' helmets, this technology can record the magnitude and direction of blows to the head during play. This technology is evolving, and we hope it will provide future help in the field of concussion research, diagnosis, and management.
Management of the injured athlete involves both immediate and long-term care. Immediate care of an athlete with a suspected concussion includes basic life support, a neurological exam on the field, and immobilization on a spine board if warranted. Hospital transport may be necessary if the athlete was rendered unconscious, had a neurological deficit, or sustained a suspected neck injury. If the athlete required assistance to the sideline, he or she should undergo further assessment including vital signs, a detailed neurological exam, mental status exam, provocative testing, and neuropsychological testing. The athlete should then be closely monitored for warning signs of further neurological damage such as persistent nausea and vomiting, changes in mental status, worsening headache, and/or seizures. Once the athlete stabilized, the decision to return to activity should be addressed by the treating sideline sports medicine team.
In determining return to play status, many clinicians use a concussion grading scale; however, there is no universally accepted scale to date. Some examples of grading scales are the Cantu, Colorado Medical Society, and the American Academy of Neurology. More recently, the Vienna Conference and the Prague Conference suggest that these scales should not be absolute rules, but each concussion should be managed individually and that grading scales may not be appropriate.
The hesitation regarding return to play issues arises from a complication known as second impact syndrome. Premature return to play may result in an additional head injury while the athlete is still in the recovery phase from the initial concussion. This then could result in brain swelling and death. This sequence of events can occur rapidly leaving no time for intervention. Other complications of concussion include post concussion syndrome (PCS), cumulative brain damage, and depression. PCS may last up to six months and is characterized by headache, dizziness, fatigue, irritability, decreased concentration and impaired memory. Athletes should be restricted from play until all symptoms have resolved.
As with any sport injury, athletes removed from play should undergo a rehabilitative program prior to return to sports. Special attention should also be given to addressing not only the sport specific but also the position specific nature of the athlete's sport.
Concussion diagnosis, management, and understanding will continue to be a challenging and dynamic issue for everyone involved in athletics. With continued efforts in research, diagnosis, prevention, and rehabilitation, concussion prevention and management will continue to improve.