Bone Abstracts

Background: Fibrodysplasia Ossificans Progressiva (FOP) is a progressive disease characterized by periods of heterotopic ossification, often in ligaments. The underlying mechanism is far from clear, partially due to limited access to patient-derived cell models. Periodontal ligament fibroblasts (PLF) from extracted teeth can potentially be used to study deviant bone remodelling processes in vitro since these cells are derived from actual ligaments. They further provid...

Hypoxia and the hypoxia-inducible factor 1alpha (Hif1alpha) are known to play critical physiological functions in endochondral bone development. However, their role in abnormal cartilage formation (chondrodysplasia) is unknown. Our goal was to test the possibility that altered oxygen homeostasis, which would result in abnormal Hif1alpha expression and activity, could lead to chondrodysplasia. This was done using matrix metalloproteinase (MMP) 9 and 13 deficient mice, which pre...

The body mass index has been regarded as a risk predictor factor for fractures, and in some prospective cohort studies it has been suggested that obesity could be a protective factor for hip fractures in adults.The present study aimed to investigate whether body mass index is related to the fracture risk when individuals had sideways falls in Mexican patients. We analyzed files from 448 patients, which checked in at Orthopedics and Traumatology Service i...

Background: Ehlers–Danlos syndrome (EDS) comprises a group of inherited connective tissue disorders, caused by various defects in the biosynthesis or secretion of fibrillar collagens. As collagen represents a major constituent of the bone matrix as well as of tendons and muscle, bone strength in EDS patients might be impaired both via direct and indirect pathways. Although decreased muscle strength, decreased areal bone mineral density (BMD) and increased fracture risk ha...

Objectives: Gorham-Stout disease (GSD) is a very rare disorder characterized by extensive angiomatous proliferation and progressive osteolysis without new bone formation. Only ~200 patients were reported. The quality of life is very poor since patients display pain, fractures, functional impairment and swelling of the affected regions. The ethiology of GSD is unknown. We aim to investigate the bone phenotype and to identify molecular and cellular defects in GSD patients.<p...

Background: Weyers acrofacial dysostosis (WAD, OMIM 193530) is a rare autosomal dominant disease, characterized by mildly short stature, postaxial polydactyly, nail dystrophy and dental anomalies. WAD should be distinguished from Ellis-van Creveld syndrome (OMIM 225500), a similar but more severe disease, comprising chondrodysplasia, orofacial anomalies and, in a proportion of patients, cardiovascular malformations. Both diseases are caused by mutations in either EVC or EVC2<s...

Objective: Rett syndrome (RTT) is an X-linked neurodevelopment disorder. More than 95% of RTT female have mutations in methyl-CpG-binding protein 2 (MECP2), whose protein product modulates gene transcription. Specific MECP2 mutations may lead phenotypic variability and different degrees of disease severity. It is known that low bone mass is a frequent complication of subjects with Rett syndrome. This study aimed to investigate if specific MECP2 mutations may affects the degree...

Osteoporosis (OP) is characterised by reduced bone mass, due to an insufficient osteoblast-mediated bone formation, unable to replace the bone tissue removed by osteoclasts. Mesenchymal stem cells (MSCs) are multipotent cells capable of differentiating into osteoblasts, adipocytes and chondrocytes. Epigenetic marks like DNA methylation could influence the differentiation potential of these cells into osteoblasts and, consequently, the risk of OP. To explore this hypothesis, we...

Background: Atypical femur fractures (AFF) arise in the subtrochanteric and diaphyseal regions. Because of this unique distribution, we hypothesized that patients with AFF demonstrate specific geometrical variations of their femur whereby baseline tensile forces applied to the lateral cortex are higher and might favor the appearance of these rare stress fractures, when exposed to bisphosphonates.Methods: Subjects who sustained AFF, as defined by the ASBM...

see PP448....