From www.ussoccer.com article "Concussions" by Daryl A. Rosenbaum, MD

A concussion is a temporary disruption of brain function caused by a sudden force transmitted to the head. We worry about concussions for a few reasons. The first is the rare chance that another blow to the head, even a mild one, while the brain is still vulnerable from the first injury could lead to severe brain swelling. Secondly, there is concern that multiple concussions could eventually add up to permanent problems with thinking and memory. Finally, even if they are short-lived, concussion symptoms can interfere with learning and social interaction during a crucial period of development in a young person’s life.

You don’t have to be “knocked out” in order to have a concussion. There are many other clues to look for that might indicate the brain is stunned including headache, confusion, memory trouble, nausea, poor balance, vision problems, and trouble concentrating.

An athlete should never return to play or even exercise while experiencing any concussion symptoms. In fact, anyone suspected of having suffered a concussion should not play again that same day even if symptoms clear up quickly. Remember the adage “when in doubt, sit them out”.

An athlete with a concussion should be evaluated by a medical doctor who can rule out other serious problems and then guide the gradual return to sports. The road back requires several days and should always be taken even more slowly with kids because young, developing brains may be more vulnerable. A general plan consists of a period of physical and mental rest followed by a trial of aerobic exercise such as running then solo soccer drills. If each step is performed without any symptoms or problems with brain function, it’s time to progressively reintroduce heading. The US Soccer protocol involves practice on a ball tossed from six yards away one day, then from no more than eighteen yards out the next day, then finally on balls thrown from beyond 18 yards on day 3. If the player can perform each step without any symptoms then he or she can resume full practice with the team.

What can be done to avoid a concussion in the first place? Proper technique can effectively reduce the force transmitted by a flying soccer ball to a player’s brain. This technique should only be taught to players who are old enough to understand the lesson. Also remember that younger players may not yet have the needed neck muscle strength to help act as a shock absorber for the head. A lighter ball or even one suspended from a string can be used at first to safely teach the basics. As for equipment, make sure that the ball is inflated to the correct pressure and of a size that is appropriate for the age group. Avoid using older cracked balls in wet conditions as they can absorb enough water to increase their weight by twenty percent. Padded goal posts can be considered and rules of fair play should be enforced.

Different types of protective headgear are marketed towards soccer players. Lab tests show that at best they don’t really soften the impact of a ball against the head and may in fact make it worse though they do seem to do a good job absorbing the force of a blow from a hard surface like a post or another player’s head or elbow. Clinical studies are not conclusive as to whether or not they actually reduce the risk of concussions. One reason could be that players wearing headgear may feel a false sense of security that causes them to play more aggressively. Mouthpieces prevent mouth and dental injuries but don’t do much to decrease concussions.

So concussions are an important health issue for soccer players, but when armed with knowledge about prevention, recognition, and appropriate management of this injury players of all levels can continue to play safe and play smart.