The ankle braces many basketball players strap on to prevent injuries may actually work, according to a study of teenaged basketball players.

Of the nearly 1,500 basketball players followed for a season, those assigned to wear ankle braces during games and practice were 68 percent less likely to suffer an ankle sprain or fracture, the authors wrote in the American Journal of Sports Medicine.

"Ankle braces could be a cost-effective way to prevent ankle injuries in basketball players, but they're not a panacea," said Timothy McGuine, at the University of Wisconsin-Madison, who led the study. "There are advertising claims that they'll do wonderful things."

Conversely, there have been concerns that limiting the ankles' mobility with a brace could set basketball players up for knee injuries, including tears of the anterior cruciate ligament. (ACL).

But in the study, which looked at the effects of "lace-up" ankle braces, which are made of synthetic fabric and secured with Velcro, found no evidence of higher knee injury risks.

Of the 740 players randomly assigned to wear lace-up ankle braces, 27 suffered an ankle sprain or fracture over one basketball season.

In contrast, there were 78 ankle injuries among the 720 teenagers who played and practiced brace-free.

That translated into an injury rate of just under 0.5 for every 1,000 practice sessions and games in the brace group. The rate in the brace-free group was about three times higher, at 1.4 per 1,000.

There was no significant difference, though, in the two groups' risk for knee injuries: there were 15 in the brace group, and 13 in the comparison group.

It's likely, McGuine said, that the softer, flexible lace-up brace does not put the knee at risk in the way that a semi-rigid plastic brace might.

But the braces do not seem to reduce the severity of ankle injuries when they do occur. 

McGuine's team found that injured players in both groups needed the same recovery time — about a week.

There are other ways to reduce basketball players' injury risk.

Studies have found, for instance, that training regimens focused on balance, coordination and jumping technique seem to cut ankle injuries to the same degree that braces did in the study — but of course these are move involved than simply strapping on a brace.

Still, the advantage of training is that it also seems to reduce the risk of knee injuries, meaning that a mix of training and ankle bracing may be best.

"The more we can do to prevent these injuries in kids, the more we'll save in healthcare costs in the long run," McGuine said.