Injuries among cheerleaders often result from gymnastic tumbling and maneuvers such as pyramid-building in which the cheerleader at the top may fall and land on a hard surface. The basket toss is another injury-prone stunt in which a cheerleader is thrown into the air 6-20 feet by other cheerleaders.

However, injuries such as bruises, twisted ankles, shin splints, head and neck injuries can also occur while cheerleaders are performing simple routines on unforgiving surfaces such as gymnasium floors. More than 16 percent of injuries involved fractures and nearly 4 percent involved concussions and other closed head injuries.

"Cheerleading has evolved into a physically demanding and competitive sport requiring complex gymnastic maneuvers that pose a serious threat of injury to participants," Dr. Daniel Green of the AAOS. "Cheerleading injuries may be prevented through increased spotter training, mandating the use of floor mats for complex stunts, and encouraging safety education and proper training for coaches."

A cheerleading squad should practice and perform only under the direction of a qualified coach and all should receive training in proper spotting techniques, the doctors group recommends.