NEW YORK (Reuters Health) - Most youngsters grow out of having otherwise unexplained bone and muscle aches known as growing pains, researchers from Israel report.

Of 35 children who originally had growing pains, Dr. Yosef Uziel, at Meir Medical Center in Kfar-Saba, and co-investigators found that 18 -- or 51 percent -- no longer had growing pains 5 years later, when they were about 13 years old.

Fourteen of the 17 who still had growing pains after 5 years said their episodes had decreased and become milder, the researchers report in The Journal of Pediatrics.

These findings, and the fact that growing pains did not result in school absences or sleep problems, hint at “the benign nature of this common syndrome,” Uziel commented in an email to Reuters Health.

Nonetheless, in both a previous look at 44 children with growing pains and the current assessment in 35 of these same youngsters, the investigators observed that kids with growing pains seem to be more sensitive to pain than their peers.

In their latest study, Uziel’s team applied metered pressure to various body points of 20 boys and 15 girls from the original cohort with growing pains. They similarly measured pain sensitivity in 38 age-matched boys and girls who did not have growing pains.

They report that 82 percent of the youngsters with continuing growing pains had at least one body point where they detected pain at a level less hurtful than a bump into a piece of furniture or a lightly stubbed toe.

They found the same in just 44 percent of the youngsters with resolved growing pains and 58 percent of those who never had growing pains.

Uziel recommends that parents explain to anxious children that growing pains are common and usually lessen over time. He notes that relaxation techniques, gentle massage, and over-the-counter pain medications may also help.

In his experience, Uziel has not seen any case of growing pains develop into a more serious pain syndrome or arthritis. But truly ruling out such a possibility requires further research in larger groups of children, he noted.

Therefore, Uziel suggests parents err on the side of caution by having a physician evaluate any child with severe or very persistent growing pains.

SOURCE: The Journal of Pediatrics, published online February 22, 2010