"Which skeletal imaging modality is best for assessing bone health in children and young adults compared to DXA? A systematic review and meta-analysis"

Bone. 2021 Sep;150:116013. doi: 10.1016/j.bone.2021.116013. Epub 2021 May 23.


Background: Skeletal imaging techniques have become clinically valuable methods for measuring and assessing bone mineral density in children and young people. Dual-energy X-ray absorptiometry (DXA) is the current reference standard for evaluating bone density, as recommended by the International Society for Clinical Densitometry (ISCD). Various bone imaging modalities, such as quantitative ultrasound (QUS), peripheral quantitative computed tomography (pQCT), high-resolution peripheral quantitative computed tomography (HR-pQCT), magnetic resonance imaging (MRI), and digital X-ray radiogrammetry (DXR) have been developed to further quantify bone health in children and adults. The purpose of this review, with meta-analysis, was to systematically research the literature to compare the various imaging methods and identify the best modality for assessing bone status in healthy papulations and children and young people with chronic disease (up to 18 years).

Methods: A systematic computerized search of Medline, PubMed, and Web of Science databases was conducted to identify English-only studies published between 1st January 1990 and 1st December 2019. In this review, clinical studies comparing imaging modalities with DXA were chosen according to the inclusion criteria. The risk of bias and quality of articles was assessed using the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2). The meta-analysis to estimate the overall correlation was performed using a Fisher Z transformation of the correlation coefficient. Additionally, the diagnostic accuracy measures of different imaging methods compared with DXA were calculated.

Results: The initial search strategy identified 13,412 papers, 29 of which matched the inclusion and exclusion criteria. Of these, twenty-two papers were included in the meta-analysis. DXA was compared to QUS in 17 papers, to DXR in 7 and to pQCT in 4 papers. A single paper compared DXA, DXR, and pQCT. The meta-analysis demonstrated that the strongest correlation was between DXR and DXA, with a coefficient of 0.71 [95%CI: 0.43; 1.00, p-value < 0.001], while the correlation coefficients between QUS and DXA, and pQCT and DXA were 0.57 [95%CI: 0.25; 0.90, p-value < 0.001] and 0.57 [95%CI: 0.46; 0.67, p-value < 0.001], respectively. The overall sensitivity and specificity were statistically significant 0.71 and 0.80, respectively.

Conclusion: No current imaging modality provides a full evaluation of bone health in children and young adults, with each method having some limitations. Compared to QUS and pQCT, DXR achieved the strongest positive relationship with DXA. DXR should be further evaluated as a reliable method for assessing bone health and as a predictor of fractures in children and young people.

Keywords: Bone densitometry; Bone health; Bone mineral density; Children; Fracture risk; Systematic review.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Absorptiometry, Photon
  • Adolescent
  • Bone Density*
  • Bone and Bones* / diagnostic imaging
  • Child
  • Humans
  • Tomography, X-Ray Computed
  • Ultrasonography
  • Young Adult