Methods for measurement of pediatric bone

Abstract

Many experts believe that optimizing bone mineral accrual early in life may prevent childhood fractures and possibly delay the development of osteoporosis later in life. Adequate nutrition and physical activity are environmental factors important in determining whether or not children acquire an appropriate amount of bone for their body size. Pediatric diseases, or therapeutic interventions used in their treatment, may interfere with normal bone development. Although there are specific methods available for assessing pediatric bone, there is no one method that can adequately assess bone health and identify the specific bone deficits that may be occurring. Understanding the biological basis for bone deficits and the ability of various bone assessment methods to discriminate or measure these deficits is important in understanding normal bone development and how to prevent and treat pediatric bone disease. The purpose of this review is to briefly describe changes in bone with growth, to define "bone density" in biological terms, to discuss some of the issues with pediatric bone measurements, and to review the three main methods for assessing bone parameters in pediatric populations. These methods, including dual energy X-ray absorptiometry (DXA), quantitative ultrasound (QUS) and peripheral quantitative computed tomography (pQCT) will be described, the advantages and disadvantages discussed, and the relationship between bone parameters and fracture risk presented for each of the methods.

Search for Promotion Factors of Ultrasound Bone Measurement in Japanese Males and Pre/Post-Menarcheal Females Aged 8-14 Years

“…Informed consent for measuring school children by a method that includes radiation exposure is diffi cult to obtain from parents. Furthermore, QUS parameters refl ect the bone stiffness, because these parameters are dependent on the density, the micro-and macrostructure, and the elastic modulus (50). Although QUS parameters may not always correspond to bone mass, these properties are important for predicting bone fracture risk, and QUS methods have been applied to many studies in Japan (13,19) and abroad (49,51).…”

Agreement between pQCT- and DXA-derived indices of bone geometry, density, and theoretical strength in females of varying age, maturity, and physical activity

“…Because aBMD does not represent a true volumetric density (BMC/volume), inter-and intraindividual differences in bone depth may be particularly influential in assessments of bone growth and adaptation. (2)(3)(4) Furthermore, DXA does not distinguish between trabecular and cortical bone and does not yield specific measures of geometry or theoretical strength, which are important parameters for describing bone growth. Because both bone mineral accrual and bone geometric growth are influential determinants of bone strength, ideal bone measurement techniques should account for variability of all measurement parameters.…”

“…(5) More critically, because pQCT samples thin slices of tissue, it is sensitive to movement and positional variation between and within subjects. (2) The latter issue may be particularly proble-matic in pediatric studies because children may find it difficult to remain still even for brief measurement periods. In addition, body size growth and variation make the assessment of analogous measurement sites challenging for intra-and intersubject comparisons.…”

Clinical utilities of quantitative ultrasound in osteoporosis associated with inflammatory rheumatic diseases

“…Care should therefore be taken in interpreting longitudinal measurements of BMD in pediatric population such as in JIA due to potential size effects (4).…”

“…In the pediatric population, the International Society of Clinical Densitometry determined low bone mineral density as a Z-score (not T-score) below -2.0 in children. T-score is not used for this definition as adolescent's bone density varies with age (3), and so it is not appropriate for growing children (4).…”