A new study presented last week in Denver at the American College of Emergency Physicians (ACEP) annual Scientific Assembly conference revealed some counterintuitive and eyebrow-raising findings: 2004-2010 saw a rise in skiing- and snowboarding-related head injuries in the United States, despite the fact that more people started riding with helmets during same period.

"Our initial hypothesis was that we would see a decrease in head injuries correlating with the increase in helmet use, and we found the opposite," said Dr. Mark Christensen, the author of the study and a resident physician in the Emergency Medicine department at Western Michigan University. "Anybody who skis has noticed that there are a lot more people wearing helmets out there -- but we didn't really have a lot of real hard evidence to show that it helps a lot. This study challenged, rather than supported, our assumptions."

Christensen cautions that he's considering his study to be preliminary at best, and concedes that a number of potentially correlating factors -- like the increase in use of terrain parks and the overall increase of skier/rider visits to U.S. ski areas -- were not taken into account. He also said that the six-year sample is too small to be statistically significant in the bigger picture: He's ultimately hoping to extend the study for a 15- or 20-year perspective.

Nonetheless, since reports of all other injuries on the slopes have remained steady while reports of head injuries have increased dramatically, the initial trends are worth taking a closer look at.

The study relies on data from the U.S. Consumer Product Safety Commission's National Electronic Injury Surveillance System (NEISS), which estimates that there were 68,761 reports of head injuries sustained while skiing or snowboarding presented to U.S. emergency departments from 2004-2010, with males (68.8 percent of total reported head injuries), snowboarders (57.9 percent), and young riders between the ages of 11-17 (47.7 percent) most likely to be injured.