title: Young adults with cystic fibrosis have altered trabecular microstructure by ITS-based morphological analysis.
abstract: Young adults with cystic fibrosis have compromised plate-like trabecular microstructure, altered axial alignment of trabeculae, and reduced connectivity between trabeculae that may contribute to the reduced bone strength and increased fracture risk observed in this patient population.
  
  
  
  The risk of fracture is increased in patients with cystic fibrosis (CF). Individual trabecular segmentation (ITS)-based morphological analysis of high-resolution peripheral quantitative computed tomography (HR-pQCT) images segments trabecular bone into individual plates and rods of different alignment and connectivity, which are important determinants of trabecular bone strength. We sought to determine whether alterations in ITS variables are present in patients with CF and may help explain their increased fracture risk.
  
  
  
  Thirty patients with CF ages 18-40 years underwent DXA scans of the hip and spine and HR-pQCT scans of the radius and tibia with further assessment of trabecular microstructure by ITS. These CF patients were compared with 60 healthy controls matched for age (±2 years), race, and gender.
  
  
  
  Plate volume fraction, thickness, and density as well as plate-plate and plate-rod connectivity were reduced, and axial alignment of trabeculae was lower in subjects with CF at both the radius and the tibia (p < 0.05 for all). At the radius, adjustment for BMI eliminated most of these differences. At the tibia, however, reductions in plate volume fraction and number, axially aligned trabeculae, and plate-plate connectivity remained significant after adjustment for BMI alone and for BMI and aBMD (p < 0.05 for all).
  
  
  
  Young adults with CF have compromised plate-like and axially aligned trabecular morphology and reduced connectivity between trabeculae. ITS analysis provides unique information about bone integrity, and these trabecular deficits may help explain the increased fracture risk in adults with CF not accounted for by BMD and/or traditional bone microarchitecture measurements.
authors.affiliation: Endocrine Unit, Department of Medicine, Massachusetts General Hospital, 50 Blossom Street, THR-1051, Boston, MA, 02114, USA. msputman@partners.org.|Division of Endocrinology, Boston Children's Hospital, Boston, MA, USA. msputman@partners.org.
authors.forename: M S
authors.initials: MS
authors.lastname: Putman
authors.affiliation: Endocrine Unit, Department of Medicine, Massachusetts General Hospital, 50 Blossom Street, THR-1051, Boston, MA, 02114, USA.
authors.forename: L B
authors.initials: LB
authors.lastname: Greenblatt
authors.affiliation: Pulmonary Division, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: L
authors.initials: L
authors.lastname: Sicilian
authors.affiliation: Division of Respiratory Diseases, Boston Children's Hospital, Boston, MA, USA.
authors.forename: A
authors.initials: A
authors.lastname: Uluer
authors.affiliation: Pulmonary Division, Department of Pediatrics, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: A
authors.initials: A
authors.lastname: Lapey
authors.affiliation: Division of Respiratory Diseases, Boston Children's Hospital, Boston, MA, USA.
authors.forename: G
authors.initials: G
authors.lastname: Sawicki
authors.affiliation: Division of Adolescent and Transition Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Gordon
authors.affiliation: Endocrine Unit, Department of Medicine, Massachusetts General Hospital, 50 Blossom Street, THR-1051, Boston, MA, 02114, USA.|Center for Advanced Orthopedic Studies, Beth Israel Deaconess Medical Center, Boston, MA, USA.|Department of Orthopedic Surgery, Harvard Medical School, Boston, MA, USA.
authors.forename: M L
authors.initials: ML
authors.lastname: Bouxsein
authors.affiliation: Endocrine Unit, Department of Medicine, Massachusetts General Hospital, 50 Blossom Street, THR-1051, Boston, MA, 02114, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Finkelstein
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D015519:Bone Density; D016022:Case-Control Studies; D003550:Cystic Fibrosis / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D011884:Radius / Q000000981:diagnostic imaging / Q000473:pathology*; D013977:Tibia / Q000000981:diagnostic imaging / Q000473:pathology*; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: Bone microarchitecture; Cystic fibrosis; Dual-energy X-ray absorptiometry; High-resolution peripheral quantitative computed tomography; Individual trabecula segmentation