Bone Abstracts

High resolution peripheral quantitative computed tomography (HR-pQCT) in combination with micro finite element analysis (μFEA) is a promising tool to assess longitudinal changes in bone mechanical properties during the fracture healing process in the distal radius. In the present study we investigate if these changes can be detected as well when using images with lower resolutions, comparable to clinical QCT images.Postmenopausal women with a stable...

Objectives: Strong coordination between osteoblasts and bone marrow cells is fundamental for the regulation of healthy bone turnover and other (patho)physiological processes. Extracellular vesicles (EVs) mediate communication between cells via horizontal transfer of proteins and nucleic acids. Osteoblasts secrete EVs in the form of matrix vesicles involved in bone mineralization, however, information about a role in intercellular communication is still lacking. In this study, ...

Infantile spinal muscular atrophy X-linked 2 (SMAX2) is a rare form of spinal muscular atrophy manifesting in severe hypotonia, areflexia, arthrogryposis, facial weakness and cryptorchidism, as frequently accompanied by bone fractures.We present a boy patient with SMAX2 who presented typical symptoms from birth, as preceded by reduced fetal movements in the second and third trimester of pregnancy. In the first days of life the patient was found to have s...

Arrest defective 1 was originally identified as an acetyltransferase essential for the life-cycle progression in yeasts. Its human orthologue hARD1 has been known to express the enzymatic activity and to acetylate several targets such as HIF-1alpha, MLCK-1, and beta-catenin. Here, whether hARD1 takes part in pre-osteoblast differentiation toward calcium-deposing osteoblast was explored. ALP staining and alizalin red S staining showed that osteoblast differentiation was negativ...

Objectives: Vitamin D dependent rickets type I (VDDR-I) is an autosomal recessive disorder with impaired activation of vitamin D, caused by mutations in CYP27B1. Characteristic clinical features are hypotonia, muscle weakness, growth failure, hypocalcemic seizures in early infancy, and radiographic findings of rickets. We aimed to describe the clinical and laboratory findings in a VDDR-1 case and to report a mutation in CYP27B1.Methods and results: The p...

Background: Mutations in the PLS3 gene, encoding plastin 3, cause X-linked osteoporosis. Osteoporosis is characterized by low bone mineral density (BMD) and increased susceptibility to fractures. Here we describe a 7-year-old boy with osteoporosis due to a novel PLS3 deletion.Presenting problem: The patient, born to non-consanguineous parents, had a history of one low-energy long-bone fracture, three vertebral fractures (T5, T6 T8) and kyphosis. DXA scan...

We report a male child presenting with antenatally diagnosed bilateral talipes equinovarus, short stature, bilateral cryptorchidism and poor weight gain; born at 39 weeks gestation (birth weight 2.56 kg) to non-consanguineous Caucasian parents. Facial dysmorphism included a prominent forehead, brachycephaly, shallow orbits, a high anterior hairline, a narrow nasal bridge and small mouth with a thin upper lip. He had white sclera and was short for height (−4.4 SDS) with a...

Background: Primary de Toni-Debré-Fanconi syndrome is a metabolic disorder characterized by hypophosphatemic rickets or osteomalacia, renal tubular acidosis, renal glycosuria, generalized aminoaciduria. It is a non-FGF23-mediated hypophosphatemic disorder, with primary defect in proximal tubular dysfunction. The orthopaedic sequela of this rare disorder in the literature is scarce.Presenting problem: We present a clinical case of a 10-year-old femal...

Young transsexuals at a minimum age of 12 years are treated with GnRH-analogues (GnRHa) to suspend pubertal development until the addition of hormones of the desired sex is started at a minimum age of 16 years. The effect of this treatment on adult bone mineral density (BMD) is still unknown. We aimed to assess BMD at the age of 22, as this is near its peak in healthy individuals.In this prospective observational study 19 female to male (FtM) and 16 male...

Background: Puberty is highly important for the accumulation of bone mass. Bone turnover and bone mineral density can be affected in transgender adolescents when puberty is postponed by gonadotropin-releasing hormone analogues (GnRHa), followed by treatment with cross-sex hormone therapy (CSHT).Objective: To investigate the effect of GnRHa and CSHT on bone turnover markers (BTMs) and bone mineral apparent density (BMAD) in transgender adolescents.<p ...