title: Bone geometry, density, and microarchitecture in the distal radius and tibia in adults with osteogenesis imperfecta type I assessed by high-resolution pQCT.
abstract: Osteogenesis imperfecta (OI) is a hereditary disorder characterized by decreased biosynthesis or impaired morphology of type I collagen that leads to decreased bone mass and increased bone fragility. We hypothesized that patients with OI have altered bone microstructure and bone geometry. In this cross-sectional study we compared patients with type I OI to age- and gender-matched healthy controls. A total of 39 (13 men and 26 women) patients with OI, aged 53 (range, 21-77) years, and 39 controls, aged 53 (range, 21-77) years, were included in the study. Twenty-seven of the patients had been treated with bisphosphonates. High-resolution peripheral quantitative computed tomography (HR-pQCT) at the distal radius and distal tibia and dual-energy X-ray absorptiometry of total hip, femoral neck, trochanteric region, and the lumbar spine (L1-L4) were performed. The patients were shorter than the controls (159 ± 10 cm versus 170 ± 9 cm, p < 0.001), but had similar body weight. In OI, areal bone mineral density (aBMD) was 8% lower at the hip (p < 0.05) and 13% lower at the spine (p < 0.001) compared with controls. The trabecular volumetric bone mineral density (vBMD) was 28% lower in radius (p < 0.001) and 38% lower in tibia (p < 0.001) in OI compared with controls. At radius, total bone area was 5% lower in OI than in controls (p < 0.05). In the tibia, cortical bone area was 18% lower in OI (p < 0.001). In both radius and tibia the number of trabeculae was lower in patients compared to the controls (35% and 38%, respectively, p < 0.001 at both sites). Furthermore, trabecular spacing was 55% higher in OI in both tibia and radius (p < 0.001 at both sites) when compared with controls. We conclude that patients with type I OI have lower aBMD, vBMD, bone area, and trabecular number when compared with healthy age- and gender-matched controls.
authors.affiliation: Department of Endocrinology, Odense University Hospital, Kloevervaenget 6. Odense, Denmark. lfolkestad@health.sdu.dk
authors.forename: Lars
authors.initials: L
authors.lastname: Folkestad
authors.forename: Jannie Dahl
authors.initials: JD
authors.lastname: Hald
authors.forename: Stinus
authors.initials: S
authors.lastname: Hansen
authors.forename: Jeppe
authors.initials: J
authors.lastname: Gram
authors.forename: Bente
authors.initials: B
authors.lastname: Langdahl
authors.forename: Bo
authors.initials: B
authors.lastname: Abrahamsen
authors.forename: Kim
authors.initials: K
authors.lastname: Brixen
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D015519:Bone Density / Q000502:physiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D010013:Osteogenesis Imperfecta / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D011884:Radius / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000503:physiopathology; D016103:Spinal Fractures / Q000000981:diagnostic imaging; D013977:Tibia / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000503:physiopathology; D013978:Tibial Fractures / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult