For baseball fans, there's nothing better than seeing your favorite member of the team make an incredible defensive play. However, as North Carolina researchers found, those diving catches may slowly be injuring players' hands.

What the researchers wanted to know: Does playing baseball injure the blood vessels of professional players' hands?

What they did: Researchers evaluated the circulation of both the gloved and throwing hands of 36 minor-league baseball players at different positions, including catcher, pitcher, infielder, and outfielder. The researchers also examined the players' hands for visible changes and measured fingers if they appeared enlarged, a marker of injury. The players reported any symptoms of hand injury, such as tingling or weakness, and specified whether they had them while playing or at rest. Investigators compared the results among different subgroups, including the different positions and throwing versus gloved hands.

What they found: While there were players in all positions that had hand abnormalities, catchers had more evidence of circulation problems than those playing other positions. These abnormalities were more common in the gloved hand than the throwing hand, indicating that having a ball slam into the mitt hundreds of times a day could cause injury. In addition, they found that the index fingers of gloved hands of 7 out of 9 of the catchers were, on average, two ring sizes bigger than the index fingers of their throwing hands. Catchers were also more likely to report symptoms such as weakness, tingling, or pain in their gloved hand. Researchers believe that the different rates of injury may be related to where the player catches the ball. Whereas noncatchers use the mitt's webbing to snag the ball, catchers get the impact closer to the hand.

What it means to you: Next time you're at the park, there's one more reason to cheer for the catcher. He could be enduring injury for the love of the game. However, even if you just play on the company softball league or catch balls hit by your child in the backyard, make sure you wear a mitt to protect your hand.

Caveats: Since this is a small study of professional athletes, one should be cautious in applying these results to recreational baseball players, who most likely are not playing nearly as much. In addition, the investigators did not compare their results to a control group of people who were not baseball players.

Find out more: The National Institutes of Health has a page on sports safety, with links to specific concerns for different sports.

The American Academy of Orthopaedic Surgeons has a fact sheet with information on baseball safety.

Read the article: Ginn, T., et al. "Vascular Changes of the Hand in Professional Baseball Players With Emphasis on Digital Ischemia in Catchers." Journal of Bone and Joint Surgery. July 2005, Vol. 87-A, No. 7, pp. 1464-1469.