Pre-teen Leg Pain Lasts in Some Cases

NEW YORK (Reuters Health) - Though leg aches and pains are a common childhood problem that usually fades quickly, some children have persistent problems into their teens, according to a new study.

Researchers in Finland found that among a group of 10- to 12-year-olds with lower-limb pain, nearly one-third still had the problem one year later, and a similar percentage had recurrent bouts of pain four years on.

Children whose pain stemmed from a physical injury, such as a broken bone, had a better prognosis than those with pain that could not be traced to a single trauma -- being less likely to complain of recurrent pain four years later.

In addition, a child's activity level helped predict his odds of chronic pain. Children who were highly active -- exercising five or more times a week -- were more than twice as likely as sedentary children to still have lower-limb pain one year into the study.

Also at risk for long-term problems were children with extremely flexible, or "hypermobile," joints. These children -- who accounted for 8 percent of those with leg pain at the start of the study -- were three times more likely than kids with less flexible joints to have recurrent bouts of pain, according to findings published in the journal Pediatrics.

Lower-limb pain is one of the most common problems of childhood, and it may become more prevalent as a growing number of kids become involved in sports, according to the study authors, led by Dr. Ashraf El-Metwally of the University of Tampere.

Traditionally, it's been assumed that common childhood leg pain will resolve naturally, over a relatively short period of time.

But the new findings, along with some other recent studies, suggest that this is not always the case, according to El-Metwally and his colleagues.

Since vigorous exercisers were among those at risk for lasting pain, it might be helpful for these children to cut down on their activities, El-Metwally told Reuters Health. He noted that this means moderating, not giving up, physical activity, as exercise is important to overall health.

The current study included 1,756 pre-adolescent Finnish children who were questioned about pain symptoms. Of these, 321 said they'd had pain somewhere in their legs at least once a week for the past three months.

Hypermobility was judged with a standard test, which includes seeing whether a person can place his palms flat on the floor without bending the knees, and whether the knees, elbows and little finger can bend backwards -- commonly referred to as being "double-jointed."

Children with a high score on this test were more likely to see their pain recur over the next four years. This did not, however, have anything to do with their exercise habits. Therefore, El-Metwally said, there's no reason to recommend that hypermobile children cut back on their activities.

It's possible, the researcher noted, that hypermobile children with recurrent pain have some type of connective tissue disorder affecting their joints -- such as the so-called hypermobility syndrome, in which extreme flexibility is accompanied by chronic joint pain.

SOURCE: Pediatrics, September 2005.