Bone Abstracts

Biographical DetailsDr Mary Leonard, MD, MSCE is a Professor of Paediatrics and Epidemiology at the Perlman School of Medicine at the University of Pennsylvania, and the Director of the Office of Clinical and Translational Research at the Children’s Hospital of Philadelphia. Her multidisciplinary research program is focused on the assessment of bone health in children, and the detrim...

Skeletal development is characterized by sex-, race- and maturation-specific increases in bone strength. Studies using conventional QCT in the spine and femur, and peripheral QCT (pQCT) in the extremities provided insight into differences in compartment volumetric BMD (vBMD) and cortical dimensions but were limited by inadequate resolution to assess microarchitecture. For example, pQCT studies demonstrated that cortical vBMD was greater in females, while cortical section modul...

Destructive bone lesions due to osteolytic bone disease (OBD) are a major cause of morbidity and mortality in multiple myeloma (MM) patients and the development of new therapeutic strategies is of great interest. In this study, we assessed the effect of SRC inhibition with saracatinib (AZD0530, AstraZeneca) on the development of MM and its associated OBD. We first determined SRC family kinase expression in the MM microenvironment and found that myeloma cells express SRC at low...

Human mesenchymal stromal cells (hMSC) have been investigated as a clinical therapy to promote tissue repair. However, the disappearance of grafted cells soon after engraftment suggests that hMSC could principally act as initiators of repair through paracrine mechanisms.The aim of this study was to evaluate the relative contribution of grafted hMSC and host cells in promoting bone tissue repair. We isolated hMSC from three bone marrow (BM) donors, then d...

Objectives: Examine changes in volumetric BMD and cortical structure following Crohn Disease (CD) diagnosis, and identify associations with growth, glucocorticoid exposure and disease activity.Methods: Prospective cohort study in 76 CD participants, ages 5–21 years. Tibia pQCT scans were obtained at diagnosis, 6, 12 and a median of 42 months later. Sex, race and age-specific Z-scores were generated based on >650 controls. Cortical dimen...

We recruited 60 healthy volunteers ages 5 to 21 to perform scan-rescan precision tests on the XtremeCT II. Participants were positioned in a carbon fiber immobilization cast. iPad-based video content was used to facilitate motion-free compliance. Distal radius and tibia scans were acquired starting 2 mm proximal to the proximal margin of the growth plate or growth plate remnant. Diaphyseal radius and tibia scans were centered at an offset from the same landmark, corresponding ...

Children with cystinosis have numerous risk factors for impaired bone accrual. We used state-of-the-art quantitative imaging of bone microarchitecture (HR-pQCT) to measure trabecular and cortical microstructure and bone strength in children and adolescents (5-20yrs) with cystinosis. We enrolled 20 cystinosis patients and recruited 34 healthy age- and gender- matched controls. Distal radius and tibia HR-pQCT scans (XtremeCT II, Scanco Medical) were acquired 2...

The impact of sex and maturation on trabecular (Tb) and cortical (Ct) microarchitecture in children and young adults has not been well established. The new second-generation high-resolution peripheral quantitative CT (HR-pQCT) scanner (XCT II, Scanco Medical) incorporates three important advances to provide greater spatial resolution, direct measures of Tb thickness and spacing and measures in the Ct midshaft. The aim of this study was to identify sex and maturation effects on...

Objectives: Alagille syndrome (ALGS) is an autosomal dominant disorder attributed to mutations in the Notch signaling pathway. Children with ALGS are at increased risk for fragility fracture, but the etiology of this disposition is unknown. Our objective was to characterize bone mass, geometry, and microarchitecture in children with ALGS.Methods: This was a cross-sectional study of 10 children (9 females) ages 8-18 years, with a clinical diagnosis of ALG...

Objective: Total body less head (TBLH) and spine are the recommended DXA sites for bone health assessment in children and adolescents. However, inter-machine differences will affect use and interpretation of results in clinical care and research applications. We examined BMC and areal-BMD (aBMD) at 4 skeletal sites among healthy children to identify the magnitude of inter-machine differences in Z-scores.Methods: BMDCS evaluated healthy participa...