title: The effects of once-weekly teriparatide on hip structure and biomechanical properties assessed by CT.
abstract: CONCLUSIONS
  Once-weekly administration of 56.5 μg teriparatide improved cortical bone parameters and biomechanical parameters at the proximal femur by CT geometry analysis.
  
  
  BACKGROUND
  The aim of this study was to evaluate the effects of weekly administration of teriparatide [human PTH (1-34)] on bone geometry, volumetric bone mineral density (vBMD), and parameters of bone strength at the proximal femur which were longitudinally investigated using computed tomography (CT).
  
  
  METHODS
  The subjects were a subgroup of a recent, randomly assigned, double-blind study (578 subjects) comparing the anti-fracture efficacy of a once-weekly subcutaneous injection of 56.5 μg teriparatide with placebo (TOWER trial).
  
  
  RESULTS
  Sixty-six ambulatory postmenopausal women with osteoporosis were enrolled at 15 study sites having multi-detector row CT, and included women injected with teriparatide (n = 29, 74.2 ± 5.1 years) or with placebo (n = 37, 74.8 ± 5.3 years). CT data were obtained at baseline and follow-up scans were performed at 48 and 72 weeks. The data were analyzed to obtain cross-sectional densitometric, geometric, and biomechanical parameters including the section modulus (SM) and buckling ratio (BR) of the femoral neck, inter-trochanter, and femoral shaft. We found that once-weekly teriparatide increased cortical thickness/cross-sectional area (CSA) and total area, and improved biomechanical properties (i.e., decreasing BR) at the femoral neck and shaft. Teriparatide did not change the cortical perimeter.
  
  
  CONCLUSIONS
  Our longitudinal analysis of proximal femur geometry by CT revealed that once-weekly administration of 56.5 μg teriparatide improved cortical bone parameters at the femoral neck and shaft and also improved biomechanical parameters.
authors.affiliation: Medical Work-Life-Balance Center, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan, masako@nagasaki-u.ac.jp.
authors.forename: M
authors.initials: M
authors.lastname: Ito
authors.forename: R
authors.initials: R
authors.lastname: Oishi
authors.forename: M
authors.initials: M
authors.lastname: Fukunaga
authors.forename: T
authors.initials: T
authors.lastname: Sone
authors.forename: T
authors.initials: T
authors.lastname: Sugimoto
authors.forename: M
authors.initials: M
authors.lastname: Shiraki
authors.forename: Y
authors.initials: Y
authors.lastname: Nishizawa
authors.forename: T
authors.initials: T
authors.lastname: Nakamura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena / Q000502:physiology; D015519:Bone Density / Q000187:drug effects / Q000502:physiology; D050071:Bone Density Conservation Agents / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000473:pathology / Q000503:physiopathology; D005272:Femur Neck / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D015663:Osteoporosis, Postmenopausal / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D019379:Teriparatide / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D014057:Tomography, X-Ray Computed
chemical_list: D050071:Bone Density Conservation Agents; D019379:Teriparatide