Shoulder injury rate higher in baseball than softball

NEW YORK (Reuters Health) - High school baseball players are somewhat more likely to suffer a shoulder injury than their female counterparts in softball -- with pitchers being at particular risk, a new study shows.

Arm overuse injuries are among the most common types of injuries in both baseball and softball. In the new study, published in the journal Pediatrics, researchers sought to find out how common shoulder injuries are among high school players, and whether the nature of the injuries differs between boys and girls.

Using injury reports from athletic trainers at 74 U.S. high schools, the researchers found that softball players sustained shoulder injuries at a rate of one injury for every 10,000 practices and games an athlete attended.

The rate among baseball players was 1.7 shoulder injuries per 10,000 “athlete exposures” -- or 70 percent higher than the rate among girls, according to the researchers, led by Dr. R. Dawn Comstock of the Research Institute at Nationwide Children’s Hospital in Columbus, Ohio.

Among baseball players, pitchers were at greatest risk, accounting for 38 percent of injuries. Among softball players, in contrast, shoulder injuries were more evenly dispersed; pitchers, catchers and first base players each accounted for 15 percent of injuries.

Baseball pitchers also suffered shoulder trauma twice as often as softball pitchers.

Most often, the injuries were not severe, the study found. Strained or partially torn muscles accounted for about one-third of all shoulder injuries in both baseball and softball. Tendonitis and ligament sprains were the next most common injuries.

Baseball players were twice as likely as softball players to need surgery; 10 percent of all shoulder injuries in baseball required surgery, versus 5 percent in softball. Pitchers accounted for most of the injuries needing surgery.

The gender differences are not unexpected, according to Comstock’s team.

Boys, they explain, tend to have greater upper body strength, allowing them to accelerate their arms faster, which puts more stress on the rotator cuff, the band of muscles and tendons that stabilize the shoulder.

In addition, baseball pitchers use the same overhand motion from the time they first take to the mound. Girls, on the other hand, learn a progression of pitching techniques before advancing to the rapid “windmill” style.

The findings, Comstock’s team writes, suggest that coaches and trainers should monitor young ballplayers’ throwing technique -- especially baseball pitchers’ -- to make sure they are not overly stressing their shoulders.

Athletes should also be guided in proper stretching and conditioning -- such as weight training -- to help strengthen the shoulder joint, the researchers say.

“Because baseball and softball are physically demanding sports,” they write, “coaches should ensure that all athletes are in adequate physical shape before they are permitted to engage in any activity.”

SOURCE: Pediatrics, March 2010.