Bone Abstracts

Hypophosphatasia (HPP) occurs when there is lack of the activity of the alkaline phosphatase protein (ALP). The principal clinical manifestations are seen in the skeleton, although some infants can develop convulsions due to the failure of pyridoxine, cleaved from pyridoxal-5-phosphate by ALP, to enter brain cells.HPP has traditionally been classified by age at presentation, with severe forms being diagnosed in utero or at birth because of fract...

Osteogenesis imperfecta (OI) is a heterogeneous group of inherited disorders of bone formation, resulting in low bone mass and an increased propensity to fracture. Over 90% of patients with OI have a mutation in COL1A1/COL1A2, which shows an autosomal dominant pattern of inheritance. Several other genes are associated with the autosomal recessive forms of OI. In-depth phenotyping and in particular, studies involving manifestations in the skin connective tissu...

Cole-Carpenter syndrome (OMIM 112240) is characterised by bone fragility, craniosynostosis, ocular proptosis, hydrocephalus and a distinctive facial appearance. Intelligence is reported to be normal. In 1986, Cole and Carpenter reported two unrelated infants with multiple fractures and deformities of bone, with a skeletal phenotype similar to severe osteogenesis imperfecta (OI). In addition, these patients also had proptosis, blue sclerae, hydrocephalus and a distinct facial g...

Objectives: The ability to discriminate bone fractures that result from non-accidental injuries and those that result from underlying bone fragility is limited by the lack of clinical instrumentation to directly measure bone mechanical properties. The BioDent Hfc (Active Life Scientific) is an experimental device that has been validated for measuring cortical bone fracture resistance in adults. We are currently developing protocols to test the feasibility of its use in infants...

Background: Case series show improved vertebral size and shape with intravenous bisphosphonate use in children with osteogenesis imperfecta (OI); however, two studies of risedronate showed no such improvement. We have re-examined the data from a dose-ranging risedronate study to determine whether other factors, in particular relating to body composition, contribute to vertebral shape in OI.Methods: We randomly assigned 53 children with moderate to severe...

Objectives and method: We retrospectively reviewed records of current patients with osteogenesis imperfecta (OI) to identify those on risedronate, doses used and effects of treatment. BMD changes over time were calculated as difference between measurement before risedronate and at one year (including measurements −3–0 m and 10–14 m after starting risedronate respectively).Results: 219/296 (74%) patients with OI had received bisphosphonate...

Background: Mechanical stimulation is thought to be critical for bone anabolic activity. It is unclear how quickly the growing skeleton responds to additional externally-applied mechanical stimuli. We wished to determine the acute effect of a standardised mechanical stimulus to the growing skeleton.Objectives: To determine the acute time course and magnitude of bone’s response to whole body vibration (WBV) in pre-pubertal boys.<p class="abstext"...

Objectives: Guidelines for treatment of vitamin D deficiency (VDD) vary. We aimed to review the range of treatment regimens for VDD used locally and variation in responses.Methods: We conducted a retrospective review of the records of consecutive patients referred to a Children’s Bone Disease Service with a putative diagnosis of VDD over a 14-month period. Data collected includes vitamin D type used, dose and duration of treatment, and pre- and post...

Background: Measurement and interpretation of metaphyseal shape in children is difficult. We aim to develop relevant assessment methods using commonly available spiral computed tomography (CT) scanning.Methods: We analysed 12 pairs of age and pubertal stage matched subjects from a larger group of children recruited into a non-interventional case–control study in which all had suffered trauma; half had sustained a fracture. Each subject underwent ant...

A first twin born at 28 weeks gestation weighing 630 g underwent an end-to-end anastamosis for colonic stricture on day 92 of life. He collapsed with severe Escherichia coli sepsis post-operatively and became anuric. Veno–veno haemofiltration (CVVH) was instituted as a life-preserving measure, continuing for 3 days.On day 119, osteopaenia and rachitic changes were noted on a chest X-ray. Review of his prior biochemistry showed a precipitous...