Snowboarders' Sprain Is Out of Joint
Broken bone often mistaken for minor ill
FRIDAY, June 1, 2001 (HealthDayNews) -- The next time you limp off the ski slopes, dragging your snowboard behind you, keep in mind that what feels like a sprained ankle may really be a broken bone. Not only that, but the injury, which could easily be misdiagnosed by a doctor as well, can lead to long-term problems if it's not treated right.
You may have broken the lateral process of the talus, a wedge-shaped section of a bone that's part of the ankle joint. A new study says it seems to happen when you cock your foot upwards and, at the same time, swivel your foot outward -- likely when you're landing after a jump or aerial maneuver. Unfortunately, it feels and looks, even on X-rays, like a "garden variety ankle sprain," said the study's lead author, Dr. Andrea J. Boon, from the Department of Physical Medicine and Rehabilitation at the Mayo Clinic in Rochester, Minn.
Proper treatment, Boon's study says, may include casts, realignment of the bones, and removal of chips or bone fragments. Without it, snowboarders may wind up with lifelong injuries that may restrict their active lives.
Snowboarding is a rapidly growing sport. The study, in a recent American Journal of Sports Medicine, says by their 12th birthdays, 80 percent of kids who take part in winter sports will have snowboarded. And according to Boon, about one-third of all ankle fractures turn out to be breaks in the lateral process of the talus. One previous study estimated that about 15 percent of all snowboarding injuries are ankle injuries.
The problem is that the fracture feels like a sprained ankle. There is, Boon said, "pain just below and in front of the bump on the outside of the ankle, with some swelling in that area and/or bruising." The injured area may not be able to bear weight, she said. "Or sometimes it does not feel that bad, and people just think they've sprained their ankle badly."
Compounding the problem is the difficulty in diagnosis: Often the fracture doesn't show up on X-rays. In fact, Boon says, CT-scans of the talus are best at detecting the break, but they're not ordinarily done on this type of injury because of the expense.
In her study, Boon tested some of the ankles on 10 cadavers to determine how exactly the injury occurs. Before snowboarding existed, fewer than 65 cases of the injury had been reported in all of the English medical literature, most resulting from high falls or car crashes. It was believed that "dorsiflexion and inversion," or bending your foot up and towards your body, under pressure, were responsible for the fracture.
But in four out of four tests of the cadavers' ankles, with increasingly greater pressure, no fracture occurred. The talus was broken only when the foot was, in addition, rotated out, and this happened in six of eight different ankles, the study said, with varying degrees of pressure applied.
The injury is rare in alpine skiing, said Jan Idzikowski, a physician's assistant at High Country Health Care in Vail, Colo. In the last nine years, he's seen maybe two or three of the fractures in skiers, versus hundreds in snowboarders. Usually it occurs during what snowboarders call a "toe-edge fall," he said. "They catch the front edge [of the snowboard on an obstacle] and fall forward." Alternatively, he said, a snowboarder will hit a tree with the leading edge of his board.
Treating the injury as a sprained ankle could result in long-term disability, Boon said. The active young people who are most likely to be snowboarders might not be able to participate when they're older in so-called "impact activities," like snowboarding and jogging.
Without surgery and realignment, the break may never heal, Idzikowski agreed. And if cartilage has chipped away and is floating in the ankle, it can wear away other cartilage, causing arthritis. "It's like gravel in your gas tank," he said.
What To Do
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