Sports Concussions a Growing Concern

A blow or jolt to the head can disrupt the normal function of the brain. This type of brain injury is often termed a concussion or "closed head injury" because the skull is not pierced by an object. Each year, 40,000 high school football players nationwide suffer concussions, which are usually considered mild traumatic brain injuries (MTBI), but still require medical attention.

Many other sports and recreational activities, including wrestling, hockey, soccer (from head collisions), snowboarding and in-line skating, can also result in concussions. Even whiplash can cause a concussion. Altogether, about 300,000 traumatic brain injuries occur each year in sports and recreation in the United States.

Several National Football League players (notably, quarterbacks Troy Aikman and Steve Young) retired after suffering several concussions during their careers. Multiple concussions suffered over a period of months or years increases the risk of permanent brain damage and post-concussion syndrome, in which neurological or cognitive problems become chronic. Even mild concussions occurring within hours, days or weeks of each other can result in "second impact syndrome," which can be fatal. As a result, coaches and trainers are showing an increased sensitivity to the effects of concussions on their players.

NFL Charities made a $20,000 first-time grant to the Medical College of Wisconsin to fund a study of high school athletes who suffer concussions. The study, carried out during 2000 and 2001, evaluated different methods of assessing recovery from concussion.

The results of this study are helping sports medicine physicians and neuropsychologists to better understand and treat athletes at all levels, as well as members of the general public who suffer head trauma.

Symptoms and Concerns
After a concussion, some people lose consciousness for a short time, but many do not. Some become dazed or confused. Because the brain is very complex and trauma to the head is different, every brain injury is different. Some symptoms may appear right away, while others might not show up for days or weeks after the concussion. Also, not all symptoms after a concussion are due to brain injury. Some can be due to neck strain or scalp bruises.

One of the difficulties of diagnosing a concussion, particularly on the sideline during a game, is the lack of an effective, universal test. The signs of concussion can be subtle. Early on, problems may be missed by patients, family members and doctors. And the injury may make it hard for patients to recognize or admit that they are having problems.

There are a broad range of concussion symptoms, including low-grade headaches that won't go away, difficulty concentrating or "feeling foggy," neck pain, ongoing fatigue or lack of energy, change in sleep patterns, increased sensitivity to sound or light, blurred vision, ringing in the ears and mood changes. Children, in addition, may act listless or irritable, lose interest in their favorite toys or have difficulty balancing or walking steadily.

Anyone with a concussion should be seen by an experienced professional. Those who were knocked unconscious should see a doctor. A computerized tomography (CT or CAT) scan and other tests may be performed to help diagnose the severity of the injury. Make sure the physician knows about any drugs being used - alcohol, natural remedies or supplements, over-the-counter or prescription medications, or street drugs. Even aspirin (or other blood thinners) might cause complications.

With a doctor's permission, acetaminophen (e.g., Tylenol) can be taken for pain. Rest is the primary treatment. While healing, individuals who have sustained a concussion should avoid activities that could lead to another brain injury.

Danger signs, which may indicate a blood clot or other serious condition, include:

• headaches that get worse
• weakness, numbness or decreased coordination
• repeated vomiting
• ongoing unconsciousness
• having one pupil (the black part in the middle of the eye) larger than the other
• convulsions or seizures
• slurred speech
• increasing confusion, restlessness or agitation

An individual with any of these symptoms should be immediately taken to an emergency room. Young children who experience any of the above symptoms or won't stop crying, can't be consoled or won't nurse or eat, should also be taken to an emergency room immediately.

Recovery from concussion varies. Most people with mild injuries recover fully, but it can take time. Recovery is typically slower in older people. People who have had a concussion in the past may find that it takes longer to recover from their current injury.

Research
Approximately 550 football players at 13 high schools in the Milwaukee, Wisconsin, area were involved in the first part of the Medical College study. They underwent a preseason assessment consisting of a standard test to check for concussion symptoms and a neuropsychological test to evaluate attention and concentration, working memory, new learning and memory, and speed of information processing.

Thirteen players suffered concussions during the season. They underwent the same tests they had taken in the preseason multiple times during the weeks following their injuries in order to track their course of recovery back to the pre-season level. In addition, six were evaluated with functional magnetic resonance imaging (fMRI), a non-invasive brain imaging technique pioneered at the Medical College.

Researchers compared the injured players' results with those from six uninjured players from the same teams. Determining the effect of the injury assists in establishing practical guidelines for managing recovery and deciding on a safe return to competition to avoid serious effects from subsequent injuries. Analysis of the initial data is still underway. Early results indicate that the injured players had good, quick recoveries.

In 2001, the study was expanded to include more than 1,500 varsity football players from 20 participating Milwaukee-area high schools. Thirty-eight subjects who sustained a concussion during a football game or practice were studied over the two seasons.

All injured subjects and a matched control were evaluated immediately after injury and at several post-injury points using the Standardized Assessment of Concussion (SAC), Post-Concussion Symptom Scale (PCSS), Balance Error Scoring System (BESS) and a brief set of neuropsychological tests. Fifteen injured subjects with a Grade 2 or 3 concussions, along with their matched control subjects, were also studied with fMRI. Thirteen of these produced usable results.

Researchers found clinical evidence of injury for several days after injury. This included alterations in general mental status, postural balance, and some impairment in recent verbal memory. Concussed players also reported a significant increase in post-concussive symptoms for several days, which appeared to resolve by 5 days after injury.

Overall, the findings suggest that individuals with Grade 2 and mild Grade 3 concussions recover neurocognitive capabilities and related neurophysiological function (as measured with fMRI) relatively quickly following injury, followed by recovery from post-concussive symptoms.

The Green Bay Packers Foundation, Herbert H. Kohl Charities, National Academy of Neuropsychology, and National Federation of State High School Associations also contributed to this research.

Thomas A. Hammeke, PhD
Professor of Neuropsychology, Medical College of Wisconsin
Froedtert & Medical College Neuroscience Center

MCW Health News presents up-to-date information on patient care and medical research by the physicians of the Medical College of Wisconsin.