title: Bone robusticity in two distinct skeletal dysplasias diverges from established patterns.
abstract: Achondroplasia (ACH) is a heritable disorder of endochondral bone formation characterized by disproportionate short stature. Osteogenesis imperfecta (OI) is a heritable bone and connective tissue disorder characterized by bone fragility. To investigate bone morphology of these groups, we retrospectively reviewed 169 de-identified bone age films from 20 individuals with ACH, 39 individuals with OI and 37 age- and sex-matched controls (matched to historical measurements from the Bolton-Brush Collection). We calculated robustness (Tt.Ar/Le) and relative cortical area (Ct.Ar/Tt.Ar) from measurements of the second metacarpal, which reflect overall bone health. Relative cortical area (RCA) is a significant predictor of fracture risk and correlates with robustness at other sites. Individuals with OI had RCH values above and robustness values below that of the control population. Bisphosphonate treatment did not significantly impact either robustness or RCA. In contrast to that reported in the unaffected population, there was no sexual dimorphism found in OI robustness or relative cortical area. We suggest that the underlying collagen abnormalities in OI override sex-specific effects. Individuals with ACH had robustness values above and RCA values below that of the control population. Sexual dimorphism was found in ACH robustness and RCH values.
  
  
  
  Identifies morphologic trends in two distinct skeletal dysplasia populations (OI and ACH) to better understand development of bone robusticity and slenderness in humans. Understanding these patterns of bone morphology is important to predict how individuals will respond to treatment and to increase treatment effect. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2392-2396, 2017.
authors.affiliation: Hospital for Special Surgery, 535 East 70th Street, New York, New York, 10021.
authors.forename: Kate
authors.initials: K
authors.lastname: Citron
authors.affiliation: Hospital for Special Surgery, 535 East 70th Street, New York, New York, 10021.
authors.forename: Cosmo
authors.initials: C
authors.lastname: Veneziale
authors.affiliation: Hospital for Special Surgery, 535 East 70th Street, New York, New York, 10021.
authors.forename: Josephine
authors.initials: J
authors.lastname: Marino
authors.affiliation: Hospital for Special Surgery, 535 East 70th Street, New York, New York, 10021.
authors.forename: Erin M
authors.initials: EM
authors.lastname: Carter
authors.affiliation: University of Michigan, Ann Arbor, Michigan.
authors.forename: Karl J
authors.initials: KJ
authors.lastname: Jepsen
authors.affiliation: Hospital for Special Surgery, 535 East 70th Street, New York, New York, 10021.
authors.forename: Cathleen
authors.initials: C
authors.lastname: Raggio
mesh_terms: D000130:Achondroplasia / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D050071:Bone Density Conservation Agents / Q000494:pharmacology / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D004164:Diphosphonates / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D050279:Metacarpal Bones / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology*; D008875:Middle Aged; D010013:Osteogenesis Imperfecta / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology*; D011859:Radiography; D012189:Retrospective Studies; D012727:Sex Characteristics; D055815:Young Adult
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates
keywords: achondroplasia; bisphosphonate treatment; bone morphology; bone robustness; osteogenesis imperfecta