Radiographic vertebral morphology: A diagnostic tool in pediatric osteoporosis
ABSTRACT To assess the value of spinal radiographs in determining the significance of reductions in bone mass or density in chronically ill children.
A pediatric scoring method for assessment of osteoporotic vertebral changes, developed on the basis of radiographs of 70 healthy controls and established adult scoring methods, was subsequently used to assess 32 pediatric patients with suspected secondary osteoporosis. Radiographic findings were correlated with bone mineral density (BMD), clinical data, and biochemistry.
Thirty-two patients (median age 14.1 years) were included. Assessment of spinal radiographs with the developed scoring method found previously undiagnosed spinal compression deformities in 11 patients (34%) of whom 9 were asymptomatic and 8 had lumbar spine (size-corrected) BMD measurements within +/-2.0 SD of the age- and sex-specific norms. Fracture history and cumulative glucocorticoid (GC) dose did not differ between those with and without compression deformities.
Vertebral compression fractures can be documented in a significant number of chronically ill children and are poorly predicted by single BMD measurements and clinical history. Assessment of vertebral morphology is recommended as an additional tool in the diagnostic workup of pediatric osteoporosis.
SourceAvailable from: Heidi H Kecskemethy[Show abstract] [Hide abstract]
ABSTRACT: The International Society for Clinical Densitometry Official Revised Positions on reporting of densitometry results in children represent current expert recommendations to assist health care providers determine which skeletal sites should be measured, which, if any, adjustments should be made, reference databases to be used, and the elements to include in a dual-energy X-ray absorptiometry report. The recommended scanning sites remain the total body less head and the posterior-anterior spine. Other sites such as the proximal femur, lateral distal femur, lateral vertebral assessment, and forearm are discussed but are only recommended for specific pediatric populations. Different methods of interpreting bone density scans in children with short stature or growth delay are presented. The use of bone mineral apparent density and height-adjusted Z-scores are recommended as suitable size adjustment techniques. The validity of appropriate reference databases and technical considerations to consider when upgrading software and hardware remain unchanged. Updated reference data sets for all contemporary bone densitometers are listed. The inclusion of relevant demographic and health information, technical details of the scan, Z-scores, and the wording “low bone mass or bone density” for Z-scores less than or equal to −2.0 standard deviation are still recommended for clinical practice. The rationale and evidence for the development of the Official Positions are provided. Changes in the grading of quality of evidence, strength of recommendation, and worldwide applicability represent a change in current evidence and/or differences in opinion of the expert panelists used to validate the position statements for the 2013 Position Development Conference.Journal of Clinical Densitometry 04/2014; 17(2). DOI:10.1016/j.jocd.2014.01.003 · 1.60 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Genetic factors play an important role in the development of osteoporosis. Several monogenic forms of osteoporosis have been recognized; most recently an X-chromosomal form resulting from mutations in the gene encoding plastin 3 (PLS3). PLS3 is a protein involved in actin bundle formation in the cytoskeleton. We present a large family with early-onset osteoporosis and X-linked inheritance. Phenotyping was performed on 19 family members and whole-exome sequencing on seven family members; five with a diagnosis of early-onset osteoporosis and two with normal bone parameters. Osteoporosis had its onset in childhood and was characterized by recurrent peripheral fractures, low BMD, vertebral compression fractures, and significant height loss in adulthood. Males were in general more severely affected than females. Bone histomorphometry findings in four males and one female showed severe trabecular osteoporosis, low amount of osteoid and decreased mineral apposition rate indicating impaired bone formation; resorption parameters were increased in some. All affected subjects shared a single base substitution (c.73-24T > A) in intron 2 of PLS3 on Xq23. The mutation, confirmed by Sanger sequencing, segregated according to the skeletal phenotype. The mutation introduces a new acceptor splice site with a predicted splice score of 0.99 and thereby, as confirmed by cDNA sequencing, induces the insertion of 22 bases between exons 2 and 3, causing a frameshift and premature termination of mRNA translation (p.Asp25Alafs*17). The mutation affects the first N-terminal calcium-binding EF-hand domain and abolishes all calcium- and actin-binding domains of the protein. Our results confirm the role of PLS3 mutations in early-onset osteoporosis. The mechanism whereby PLS3 affects bone health is unclear, but it may be linked to osteocyte dendrite function and skeletal mechanosensing. Future studies are needed to elucidate the role of PLS3 in osteoporosis and to define optimal treatment. © 2014 American Society for Bone and Mineral ResearchJournal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 09/2014; 30(3). DOI:10.1002/jbmr.2355 · 6.59 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: This study of changes in dual energy x-ray absorptiometry (DXA) spine BMD following diagnosis and treatment for childhood Crohn's disease demonstrated that changes in conventional posteroanterior BMD results were confounded by impaired growth, and suggested that lateral spine measurements and strategies to estimate volumetric BMD were more sensitive to disease and treatment effects. We previously reported significant increases in peripheral quantitative CT (pQCT) measures of trabecular volumetric bone mineral density (vBMD) following diagnosis and treatment of pediatric Crohn's disease (CD). The objective of this study was to compare pQCT trabecular vBMD and three DXA measures of spine BMD in this cohort: (1) conventional posteroanterior BMD (PA-BMD), (2) PA-BMD adjusted for height Z (PA-BMDHtZ), and (3) width-adjusted volumetric BMD (WA-BMD) estimated from PA and lateral scans. Spine DXA [lumbar (L1-4) for posteroanterior and L3 for lateral] and tibia pQCT scans were obtained in 65 CD subjects (ages 7-18 years) at diagnosis and 12 months later. BMD results were converted to sex, race, and age-specific Z-scores based on reference data in >650 children (ages 5-21 years). Multivariable linear regression models identified factors associated with BMD Z-scores. At CD diagnosis, all BMD Z-scores were lower compared with the reference children (all p values <0.01). The pQCT vBMD Z-scores (-1.46 ± 1.30) were lower compared with DXA PA-BMD (-0.75 ± 0.98), PA-BMDHtZ (-0.53 ± 0.87), and WA-BMD (-0.61 ± 1.10) among CD participants. Only PA-BMD Z-scores were correlated with height Z-scores at baseline (R = 0.47, p < 0.0001). pQCT and WA-BMD Z-scores increased significantly over 12 months to -1.04 ± 1.26 and -0.20 ± 1.14, respectively. Changes in all four BMD Z-scores were positively associated with changes in height Z-scores (p < 0.05). Glucocorticoid doses were inversely associated with changes in WA-BMD (p < 0.01) only. Conventional and height Z-score-adjusted PA DXA methods did not demonstrate the significant increases in trabecular vBMD noted on pQCT and WA-BMD scans. WA-BMD captured glucocorticoid effects, potentially due to isolation of the vertebral body on the lateral projection. Future studies are needed to identify the BMD measure that provides greatest fracture discrimination in CD.Osteoporosis International 04/2014; DOI:10.1007/s00198-014-2701-x · 4.17 Impact Factor