THE PHYSICIAN AND SPORTSMEDICINE - VOL 31 - NO. 11 - NOVEMBER 2003
A Rise in Kids' Distal Forearm Fractures
What's the Cause?
Physicians anticipate distal forearm fractures among young adolescents, because growing bones are more porous at a time when children are active in sports and recreational activities. Mayo Clinic researchers, however, have noted a steep increase in the number of distal forearm fractures over the past three decades. Their findings raise questions about the possible role of changing activity patterns and dietary habits.
Sports that carry higher fracture risks, such as in-line skating and snowboarding, have become more popular among many young people at a time when overall inactivity levels are increasing among their peers. Over the same time period, milk consumption—and the calcium that comes with it—has been eroded by the popularity of soda and other beverages.
Tracking Fracture Trends
In examining trends in distal forearm fracture rates, a study by the Mayo clinic researchers1 compared data collected during the 1970s, 1980s, and 1990s with a baseline rate reported in the same population.2 Researchers drew their information on distal forearm fractures from a unique database. Nearly all medical care delivered around Rochester, Minnesota, is available for study because medical care is centralized among a few providers and linked through the Rochester Epidemiology Project.
The current study examined all distal forearm fractures in patients younger than 35 during three 3-year periods: 1979-1981, 1989-1991, and 1999-2001. The investigators compared the findings to previously published data from 1969-1971.2 Fractures were classified by cause: pathologic process, serious trauma (with subcategories for recreational and occupational injuries), and moderate trauma.
They found that the overall annual incidence rate per 100,000 subjects in the study group rose 42% between 1969-1971 and 1999-2001. Broken down by gender, the rate in male subjects rose by 32%, and the rate in female subjects rose by 56%.
When examining fracture etiology patterns, researchers found that fractures associated with recreational activities, which doubled, were responsible for the change in fracture rates between the two time periods. The distribution of recreational injuries was fairly constant across all of the time periods that were studied, though there were some increases in skiing and skating activity among boys and basketball, soccer, and skating among girls.
Forearm fractures peak between ages 8 to 11 in girls and between ages 11 and 14 in boys.
What's Behind the Increase?
Sundeep Khosla, MD, lead author of the study and professor of medicine in the Endocrine Research Unit at the Mayo Clinic in Rochester, says researchers were surprised by the size of the increase in distal forearm fractures. Though the point of the study wasn't to identify a cause, the rise in fracture rates raises questions about possible causes. "We're careful not to overinterpret the results, but it's an open question," he says, noting that decreased physical activity levels, changes in recreational activity trends, and changes in nutrition patterns may all play a role.
Researchers will be following up on the causes of increased fracture rates, he says, but in the meanwhile, it might be useful for physicians to emphasize the importance of bone-health behaviors—adequate calcium intake and physical activity—to young patients and their parents. Adolescents should be getting about 1,300 mg of calcium per day, Khosla says. "If the diet is inadequate, supplements may be necessary."
David T. Bernhardt, MD, Adolescent and Sports Medicine Fellowship director and associate professor in the Department of Pediatrics at the University of Wisconsin in Madison says the results of the Mayo study are consistent with the patterns he's seen among his patients. Though he says none of the causes suggested by the authors can be proven so far, another possible contributor may be lack of appropriate wrist protection in in-line skaters, ice skaters, snowboarders, and skateboarders. "Many of these activities are more popular today than in the 1969-1971 study period and may contribute significantly to their results," he says.
"The bottom line," Bernhardt says, "is prevention is the key, with wearing of proper equipment in at-risk activities when possible." He notes that detailed safety recommendations for in-line skating and skateboarding can be found on the policy statement section of the American Academy of Pediatrics Web site. "Also, optimizing nutrition in terms of calcium and vitamin D may be important, though a direct causal link in terms of bone density needs to be established," Bernhardt says.
Magnetic Insoles Don't Help Heel Pain
Magnetic shoe inserts provided no greater pain relief than placebo inserts, according to a report in the September 17 issue of The Journal of the American Medical Association.
The Mayo Clinic researchers who conducted the randomized, double-blind, placebo-controlled trial enrolled 101 adults with at least a 30-day history of heel pain. The patients were instructed to wear the insoles for at least 4 hours a day, 4 days a week, for 8 weeks. Participants kept daily pain diaries, rating their pain on a 10-point scale.
Both the magnet and sham groups reported significant improvement in morning foot pain. At the end of the study, 35% of the magnetic group and 33% of the nonmagnetic group reported being all or mostly better. The authors noted that Americans spend about $500 million each year on magnets to treat pain.
Knee Arthritis Study Vindicates High Heels
Researchers investigating the causes of knee osteoarthritis in women have found that high heels don't appear to contribute to the condition, though excessive weight gain before age 40 does seem to have an effect.
By age 65, knee osteoarthritis is twice as common in women as in men. Researchers have been trying to determine why the condition is more common in older women, and some have speculated that wearing high-heeled shoes may be partly to blame.
The study, which appeared in the October issue of the Journal of Epidemiology and Community Health, was done on 27 British women who were awaiting knee replacement and 82 age-matched controls. Women were interviewed about their health, occupational history, shoe-wearing history, and life events.