Osteoporosis in children: 2002 guidelines do not apply
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* Shayne P. Taback

The 2002 clinical practice guidelines for the diagnosis and management of osteoporosis in Canada1 cover both primary and secondary osteoporosis, but it is important to remember that these guidelines are based on evidence and experience with adult patients only and hence may not be applicable to younger patients.

Children and adolescents also experience fragility fractures, albeit rarely. In addition to their occurrence in association with genetic diseases (such as osteogenesis imperfecta), pediatric fragility fractures are seen in patients with immobilization (e.g., because of spinal cord injury), inflammatory diseases (e.g., juvenile idiopathic arthritis), glucocorticoid pharmacotherapy and combinations of these factors, sometimes with concomitant nutritional deficiencies of calcium and vitamin D; such fractures may also occur in patients with hypogonadism. 

However, the World Health Organization densitometry categories2,3 cannot be applied in these cases, as T-scores for children calculated by standard methods are falsely low because there is no adjustment for their smaller size.4 Although T-scores should be neither computed nor reported for children, interpretation of pediatric densitometry results is possible if one has knowledge of various normal ranges for bone mass that depend on age, sex, bone size, pubertal tempo and pubertal stage. This process is analogous to analyzing children's growth curves without knowing the parents' heights. 

Also currently lacking are data relating bone mass measurements to fracture risk in these special populations. As a result, it may be advisable to diagnose and consider pharmacotherapy for pediatric osteoporosis in the severe category — children who have already experienced a fragility fracture and who have identifiable risk factors. This definition is conservative but probably appropriate, given the lack of sufficient efficacy and safety data in children for the agents used for preventing fractures in older adults. 

As Canadian child health programs develop recommendations for care for osteoporosis in children, it is hoped that diagnostic and clinical trials research will progress to the point that satisfying, evidence-based guidelines on the management of pediatric osteoporosis can one day be included.

**Shayne P. Taback** Section of Endocrinology and Metabolism Department of Pediatrics and Child Health University of Manitoba Winnipeg, Man.

## References

1.  1. Brown JP, Josse RG, for the Scientific Advisory Council of the Osteoporosis Society of Canada. 2002 clinical practice guidelines for the diagnosis and management of osteoporosis in Canada. CMAJ 2002;167(10 Suppl):S1-34.
    
    

2.  2. *Assessment of fracture risk and its application to screening for postmenopausal osteoporosis: report of a WHO Study Group*. Technical Reports series. Geneva: World Health Organization; 1994. 
    
    

3.  3. Kanis JA, Melton LJ 3rd, Christiansen C, Johnston CC, Khaltaev N. The diagnosis of osteoporosis.J Bone Miner Res 1994;9:1137-41.
    
    [PubMed](http://www.cmaj.ca/lookup/external-ref?access_num=7976495&link_type=MED&atom=%2Fcmaj%2F168%2F6%2F675.2.atom) 
    
    [Web of Science](http://www.cmaj.ca/lookup/external-ref?access_num=A1994NY39200001&link_type=ISI) 

4.  4. Prentice A, Parsons TJ, Cole TJ. Uncritical use of bone mineral density in absorptiometry may lead to size-related artifacts in the identification of bone mineral determinants. Am J Clin Nutr 1994; 60:837-42. 
    
    [Abstract/FREE Full Text](http://www.cmaj.ca/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpjbiI7czo1OiJyZXNpZCI7czo4OiI2MC82LzgzNyI7czo0OiJhdG9tIjtzOjIyOiIvY21hai8xNjgvNi82NzUuMi5hdG9tIjt9czo4OiJmcmFnbWVudCI7czowOiIiO30=)