There has been a great deal of controversy recently regarding the role of the head in soccer and whether playing soccer is dangerous to the brain. The American Academy of Pediatrics classifies soccer as a "contact/collision" sport, and parents and athletes have become increasingly concerned about potential brain damage from the sport.

Some physicians have sought to require helmets or some form of headgear for soccer players. Several types of products are now on the market for soccer players that purport to protect the brain. The NCAA Committee on Competitive Safeguards and Medical Aspects of Sports has been approached about the use of head protection devices for soccer players.

Soccer is a unique sport in that the head is used as a piece of equipment to direct the ball; the average elite soccer player heads the ball five to 10 times per game and many more times in practice. Because of this use, there is concern about head trauma from both repetitive ball-head impacts and acute contact with other players, the ground and fixed objects.

Types of head injury mechanisms

Repetitive ball-head impact: Some researchers have become concerned that low-level head-ball impacts may have a cumulative effect on the brain and result in a chronic brain injury, similar to the "dementia pugilistica" syndrome in professional boxers.

Acute head impact: Soccer players also are at risk for head trauma through acute contact with other players, the ball or other objects such as goalposts. This contact may result in brain injury such as concussions.

The unanswered questions include:

Does repetitive heading of the ball have a cumulative detrimental effect on the brain? If so, how can it be quantified?

Does repetitive heading of the ball make one more susceptible to acute concussions because of their previous exposure?

What is the mechanism behind acute concussions in soccer?

The 1999-00 NCAA Injury Surveillance System (ISS) report for soccer showed that 7 percent of all reported women's injuries (11 percent of all game injuries) and 4 percent of all reported men's injuries (7 percent of all game injuries) were concussions. Soccer players are at risk for concussions; what is not as well-known is the mechanism.

Is the brain at risk from repetitive heading of the ball, acute concussions or both? My own research with the U.S. Men's National Soccer Team seems to indicate that it is acute concussions that are the main culprit in any type of brain injury to soccer players, just as we have seen with other sports, such as football. However, we still do not know the exact mechanisms behind acute concussions in soccer and there has been a great deal of confusion in this area. For example, if two players collide with each other while going up to head a ball, some would consider this a "heading" injury rather than player-player contact.

Need for headgear?

Until the true cause of acute concussions can be answered, we do not know if head gear would even reduce acute concussions in soccer. We have examples in other sports of head gear having the unintended consequence of increasing injuries. We must be very careful about advocating major equipment changes before thorough study has been done. It also should be noted that most head protection does not protect against acute traumatic brain injury (concussion). A concussion results from a rapid acceleration or deceleration of the brain. For example, a player falling to a surface and hitting the back of his head may incur a concussion. This is due to the rapid deceleration of the brain as the head stops suddenly upon impact. In this scenario, the helmet reduces direct impact to the head, protecting against internal bleeding. It does little, however, to buffer the rapid deceleration of the brain, resulting in a concussion.

In the meantime, I would suggest the following:

Strict enforcement of the existing rules, especially in the area of dangerous play.

Further research into the exact mechanism of acute concussions. My research group is beginning this study and will be asking institutions to participate in the future.

Consideration of padding the goal posts. This has been tried in some parts of the country and it has resulted in a marked reduction in injuries without influencing play.

Consideration of mouth-guard use. Mouth guards are used in all sports with a high risk for concussion and there is some evidence to suggest that mouth guards reduce the forces transmitted to the brain. If an NCAA quarterback can call signals in front of 80,000 screaming fans, soccer players can communicate across the pitch with a mouth guard.

No use of headgear in soccer until further research has been done. At a minimum, studies need to assess the reduction in forces with specific types of headgear in relation to heading a ball. There is no evidence to date demonstrating that the use of headgear would reduce brain injuries in soccer.

As the popularity of both men's and women's soccer increases, there will be continued interest in making soccer a safe sport. In this regard, we must ensure that any decisions to change the game are based on solid research and only after thorough discussion between researchers, physicians, coaches, trainers and players.