I have a son who is very healthy. However, he has had three fractures over the past two years. Should I be concerned?
Bone fractures are not uncommon in childhood, but it is less frequent for children to have more than one or two fractures. Most children who present with multiple fractures have normal skeletal health. They are usually prone to fractures because of higher levels of exposure to sports or other activities which predispose them to fractures.
Conditions which cause weak bones are less likely to be the reason for fractures. Usually these conditions involve some kidney diseases, and rarely endocrinological conditions.
In a recent study published in Pediatrics (May 2008), Dr. Robert Olney and associates addressed the issue of how much evaluation is needed for a child with a history of multiple fractures (“Healthy Children with Frequent Fractures: How Much Evaluation is Needed?”, pp 890-897). The authors concluded that it is important to look at a child’s urine, specifically the amount of calcium which gets excreted. The test for this involves looking at the urinary calcium to creatinine ratio; if the ratio is above 2, it may be a concern.
Another factor which plays a role, according to this study, is a delay in the onset of puberty. The authors underscore the importance of making sure that calcium and vitamin D intakes are monitored carefully.
The most recent recommendations indicate that, ideally, children over the age of two years should use 1,000 International Units (I.U.) of vitamin D3 per day. It is important that the vitamin be D3 not D2, given D2 is a third as potent as D3. This is especially important during the winter months and more so when one lives above the 33rd latitude. (For some ideas on how to get vitamin D drops for families, see www.ddrops.ca).
The daily calcium needs in children — given one cup (250 ml) of milk provides close to 100 I.U. of vitamin D — varies by age and gender:
- infants up to one year old need 350 to 400 mg of calcium daily
- between 1-3 years the need per day is 500 mg (one and a half cups)
- between 4-6 years the need is 600 mg (2 cups)
- from 7-9 years the need is 700 mg (two and a quarter cups)
- males between 13 to 15 years need 1,100 mg per day (three and a half cups)
- females between 13 to 15 years need 800 mg per day (two and a half cups)
- the highest need in females is between ages 1 and 12 (1000 mg per day, close to three and a half cups)
Not all children get their vitamin D levels checked routinely - even here in Canada where we live at high latitude. The test is done by asking your doctor to do a 25-hydroxy vitamin D level. Very often, this level is below normal, especially if the child sees very little sunshine, avoids diary products for whatever reason, is over weight, or does not take vitamin D supplements. (For more information on other conditions associated with low vitamin D levels, such as Multiple Sclerosis, diabetes and cancer, see www.healthykds.ca).
An interesting discovery discussed in the Pediatrics paper is the fact that weight bearing activities in children are not associated with stronger bones - something which is not true for older patients. For example, women who engage in weight bearing activities reduce their risks of having weak bones.
A special type of X-ray - known as a dual-energy radiographic absorptiometry (DXA) - is needed to asses a child’s bone density. A DXA scan in children and adolescents is not without controversy. A number of experts feel that the reference values used for children are not reliable as compared to values used in adults. However, even with limitations and disagreement over the exact validity of a DXA scan, the authors of the May 2008 Pediatrics article suggest that in healthy children who have a high level of calcium in the urine, a poor intake of calcium and vitamin D, and a delayed onset of puberty must get a DXA scan to evaluate their bone health in more detail.
The bottom line is that when an otherwise healthy child suffers from repeated fractures, it is mostly a matter of just that - frequent fractures - as opposed to serious bone disease. Furthermore, it helps to eat healthy (drink milk or take calcium supplements and vitamin D3 supplements) and keep one’s weight in the ideal range. An over-consumption of soda pop containing chemicals, which over time may add to a weakening of bones, should also be avoided.
If they know your child by his first name in the ER due to frequent fractures, then it may be time to ask the doctor to run a few of these investigations!
Access www.healthykids.ca for a terrific new resource in helping families raise healthy children - HealthyKids with Dr. Nieman will optimize your child's complete health.
An informed parent is ... an empowered parent.