Concussion is classified as a minor head injury caused by a blow or a sudden jolt to the head that leads to the head being violently propelled forward and backward, causing the brain to bounce off the skull. This is more common in sports like boxing, American football, ice hockey, cricket and baseball where the chances of being hit on the head are very high. Concussions are also seen after falls or motor vehicle accidents, where it may precede a more serious brain injury. Impact causes biochemical changes in the brain transiently altering function- typically affecting memory and orientation.
Evaluation of the concussed athlete is performed on the basis of a checklist of symptoms and signs (The Post Concussion Symptom Scale and the Graded Symptom Checklist) that are administered by trained personnel, usually at the site of injury. The lists check 4 major neuro-cognitive domains- orientation, immediate memory, concentration and delayed recall. On being hit on the head, patients usually appear dazed and confused, speaking slowly and indistinctly. They may be unconscious transiently or unable to recall exactly what happened immediately preceding or following the injury – known in medical parlance as post-traumatic amnesia. Following simple commands may be a challenge, walking may be difficult with patients frequently lurching from side to side. Patients may also complain of headache or a pressure inside the head, feeling dizzy and unable to tolerate the surrounding light or noise. In the hours to days following impact, patients exhibit problems in concentration, but the majority of symptoms disappear in about 2 weeks following the injury.
A concussion may be the start of a more severe brain injury. The following are the signs and symptoms of a more severe underlying injury
Risk for prolonged or severe early impairments, neurological catastrophe or chronic behavioral issues.
In the majority of cases symptoms will settle with time. Children usually feel better in a few days and are expected to be asymptomatic at the end of two weeks. However, younger children, athletes with a history of several concussive episodes especially within 10 days of the initial episode, are more prone to prolonged post-concussive effects. Risk factors for chronic neurobehavioral impairment include concussion and APOE ε4 genotype.
As each injury is unique and the ability of each athlete to recover is also variable, there is no hard and fast rule that applies. However, current NFL guidelines are broadly followed. An athlete who has been concussed is usually asked to rest for a couple of weeks, with almost no physical activity and limited use of electronics and social media. A qualified practitioner usually checks on the person daily, if possible. If asymptomatic, going to school or light training with the team can resume in the following week. Activity can be slowly increased over the next few weeks from mild to moderate and then strenuous physical exercise followed by full contact training and match play. If symptomatic at any point, physical activity must be stopped immediately. A visit to a specialist is advised at this point for more advanced neuropsychological testing or even imaging studies of the brain. Resuming activity must be done slowly, with expert guidance and supervision.
Athletes who have been concussed several times and have residual symptoms or long-term neuropsychological symptoms may be asked to retire from the sport. This decision to retire must be discussed at length and over a period of time with the person, his athlete, his near and dear and even his teammates by a senior medical practitioner who understands the effects of repeated impacts to the head.