Position StatementFracture Prediction and the Definition of Osteoporosis in Children and Adolescents: The ISCD 2007 Pediatric Official Positions
Introduction
Dual-energy X-ray absorptiometry (DXA) was originally devised for use in adults. However, DXA studies are now performed with increasing frequency in children and adolescents as well. The clinical use of bone densitometry in adults is mainly based on epidemiological studies that have found an association between densitometric measurements, such as areal bone mineral density (BMD) bone mineral content (BMC), and fracture incidence in a number of populations 1, 2, 3, 4. However, results in adults cannot be simply extrapolated to the pediatric age range for a variety of reasons, including the influence of growth on DXA results and the different fracture epidemiology in children and adolescents.
The incidence of fracture in healthy children or adolescents is similar to the lifetime risk of osteoporotic fracture as an adult 5, 6, 7. Between a third and one half of all children will have at least one fracture by the end of their teenage years 5, 8. Nevertheless, the characteristics of fractures differ markedly between healthy children and osteoporotic adults. Adults with osteoporosis frequently sustain hip and spine fractures, whereas such fractures are very rare in healthy children. In osteoporotic adults, fractures often are caused by a simple fall from standing height, but healthy children sustain fractures commonly during more forceful trauma, such as falls from playground equipment or sports activities 5, 9. In adults, osteoporosis is more common in females, whereas in children more fractures occur in the male sex (7).
This task force was asked to examine the following questions:
- •
Are DXA measures predictive of fractures in apparently healthy children and adolescents?
- •
What are the densitometric criteria for the diagnosis of osteoporosis in a child or adolescent?
Section snippets
Methodology
A literature search was performed using the PubMed and OVID MEDLINE databases for the time period from 1966 to February 2007. Combinations of the terms “bone mineral density”, “BMD”, “BMAD”, “children”, “adolescents”, “pediatric,” and “fractures” were used. Studies were included if they utilized measurements by DXA in apparently healthy children and/or adolescents, and analyzed the relationship of the measurements with fracture occurrence. Studies in premature babies and young infants were not
ISCD Official Position
- •
Fracture prediction should primarily identify children at risk of clinically significant fractures, such as fracture of long bones in the lower extremities, vertebral compression fractures, or two or more long-bone fractures of the upper extremities.
Grade: Fair-C-W-Necessary
ISCD Official Positions
The diagnosis of osteoporosis in children and adolescents should NOT be made on the basis of densitometric criteria alone.
- •
The diagnosis of osteoporosis requires the presence of both a clinically significant fracture history and low bone mineral content or bone mineral density.
- ○
A clinically significant fracture history is one or more of the following:
- ■
Long bone fracture of the lower extremities
- ■
Vertebral compression fracture
- ■
Two or more long-bone fractures of the upper extremities
- ■
Low BMC or BMD is
- ■
- ○
Additional Questions/Suggestions for Future Research
- •
What is the morbidity following fractures in children and adolescents?
- •
How often do fractures lead to hospitalization, surgery, chronic pain or residual functional deficits?
- •
Are DXA results predictive of further fractures in otherwise healthy children who have a clinically significant fracture history?
Summary
The ISCD Official Positions provided here define osteoporosis in the pediatric age range. The diagnosis of osteoporosis is based on both clinical information (fracture history), and densitometric criteria. As more information becomes available, the criteria for the diagnosis of osteoporosis in children and adolescents may undergo modifications in the future.
References (29)
- et al.
Epidemiology of osteoporosis
Rheum Dis Clin North Am
(2006) - et al.
Bone mineral density and body composition in boys with distal forearm fractures: a dual-energy X-ray absorptiometry study
J Pediatr
(2001) - et al.
Bone density interpretation and relevance in Caucasian children aged 9–17 years of age: insights from a population-based fracture study
J Clin Densitom
(2006) - et al.
Fractures and recurrent fractures in children: varying effects of environmental factors as well as bone size and mass
Bone
(2006) - et al.
Bone densitometry of the spine and femur in children by dual-energy X-ray absorptiometry
Bone Miner
(1992) - et al.
Comparison of different models for interpreting bone mineral density measurements using DXA and MRI technology
Bone
(1995) - et al.
DXA estimates of vertebral volumetric bone mineral density in children: potential advantages of paired posteroanterior and lateral scans
J Clin Densitom
(2006) - et al.
Ten year probabilities of osteoporotic fractures according to BMD and diagnostic thresholds
Osteoporos Int
(2001) - et al.
Predictive value of BMD for hip and other fractures
J Bone Miner Res
(2005) - et al.
Bone mineral density predicts osteoporotic fractures in elderly men: the MINOS study
Osteoporos Int
(2005)