Quantitative CT Reference Values for Vertebral Trabecular Bone Density in Children and Young Adults

Abstract

Purpose:To determine normative reference values for vertebral trabecular bone density (TBD) obtained by using quantitative computed tomography (CT) in healthy white children, teenagers, and young adults of both sexes. Materials and Methods:The data presented in this HIPAA-compliant study are a compilation of data from multiple investigations on the determinants of bone acquisition in healthy children conducted at this institution from 1992 to 2006. The institutional review board for clinical investigations approved the protocols for each of these studies, and written informed consent was provided by all parents and/or participants. Quantitative CT measurements of TBD (in milligrams per cubic centimeter) were obtained at the first, second, and third lumbar vertebrae in 1222 healthy white male and female subjects aged 5-21 years (mean age for male subjects, 15.1 years Ϯ 3.6 [standard deviation]; range, 5.6 -21.9 years; mean age for female subjects, 14.2 years Ϯ 3.9; range, 5.7-21.6 years; mean age for both sexes, 14.6 years Ϯ 3.8). Mean and standard deviations for TBD were determined for each age group in 1-year intervals, and Student t tests for unpaired data were performed to compare male subjects with female subjects. Results:TBD increased equally during growth in male and female subjects. Although the percentage increase in TBD was similar for both sexes (23.7% [57 of 241] for male subjects, 22.2% [54 of 243] for female subjects), the rise began and reached peak values at an earlier age in female subjects; increases in TBD occurred from 10 -15 years of age in female subjects, whereas in male subjects, these increases were not observed until age 12 years and were completed at 17 years. Conclusion:This study provides reference standards for quantitative CT bone measurements in children and young adults, which may aid in the diagnosis, prevention, and treatment of pediatric metabolic bone disorders. Note: This copy is for your personal, non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, use the Radiology Reprints form at the end of this article.M easurements of bone density during childhood are commonly obtained to assess the deficiencies in bone accumulation associated with a multitude of pediatric disorders. Moreover, the amount of bone that is gained during growth is an important determinant of the risk for osteoporosis later in life (1,2), and available data suggest that the genetic susceptibility to osteoporosis is detectable in childhood (3). Peak bone mass, a major determinant of the future risk of fractures in the elderly, is largely achieved by the end of sexual development (4).Because of its availability, minimal radiation exposure, and relative ease of use, dual-energy x-ray absorptiometry (DXA) is the most commonly employed quantitative radiologic method to assess bone mass at any age (5). The interpretation of DXA bone studies is considerably more challenging in children than in adults. Although reference data and diagnostic algorithms are avai...

Quantitative Computerized Tomography (QCT) versus Dual X-Ray Absorptiometry (DXA) in the Assessment of Bone Mineral Density of HIV-1 Infected Children

“…All of the patients on tenofovir DF had elevated urinary NTx values. Table 2 demonstrates the anthopometric characteristics of the study population and that of a control population used as normative data [13]. There were no statistically significant differences between both groups.…”

“…Subjects with scoliosis of more than 20 degrees or kyphosis of more than 40 degrees, previous surgery with metal pins, rods, screws, or staples, a non-removable body piercing in the chest or abdomen, or current pregnancy were excluded. Study subjects were matched by race, gender, and age to a control group of healthy, uninfected children whose anthropometric measures and imaging findings by CT and DXA were recorded in an anonymous imaging database of national standards for healthy subjects generated in prior studies [13].…”

“…Identification of the sites to be scanned was performed with lateral scout views, and the density of cancellous bone in the lumbar vertebrae was obtained from the 10 mm midportion of the vertebral bodies. The average density was calculated and compared with published normative data from our laboratory [13] to determine the CT z-score. Coefficients of variation for repeated CT measurements of vertebral density were approximately 1.5% [13,14].…”

“…The average density was calculated and compared with published normative data from our laboratory [13] to determine the CT z-score. Coefficients of variation for repeated CT measurements of vertebral density were approximately 1.5% [13,14]. The time required for the procedure was 10 minutes.…”

Bone Health in Disorders of Sex Differentiation

“…In young adulthood, men and women have similar volumetric BMD, but men have bigger bones than women due to the process of periosteal apposition [Seeman, 2001]. Volumetric BMD is independent of age for the vertebral body, at least until puberty [Gilsanz et al, 2009], then it increases comparably by gender. At puberty, trabecular BMD grows by increasing the size and thickness of the trabeculae to a similar degree in boys and girls [Seeman, 2008].…”