title: Bone microarchitecture and strength of the radius and tibia in a reference population of young adults: an HR-pQCT study.
abstract: Within a normative youth cohort (16-29 years) bone parameters for males and females remained stable at the radius. At the tibia, a peak was observed for females at 16-19 years, with bone density and strength decreasing by 29 years.
  
  
  OBJECTIVE
  To determine if bone microstructural and strength parameters identified by high-resolution peripheral quantitative computed tomography (HR-pQCT) and finite element analysis (FEA) at the distal radius and tibia, peak within the age range of this youth cohort, and whether the timing of the peaks differ based on sex or skeletal site.
  
  
  METHODS
  We recruited 251 participants (158 female; 16 to 29 years), grouping them into 5-year age brackets (16-19; 20-24; 25-29 years) assessing microstructural and strength parameters with HR-pQCT and FEA.
  
  
  RESULTS
  HR-pQCT assessment of males and females (age-matched groups) showed males had higher total area and BMD, trabecular BMD and trabecular number (radius only) cortical thickness and porosity, and failure load, but lower cortical BMD (p < 0.05). Within sex, microstructural and strength parameters remained stable for males, but in females they appeared to peak at 16-19 years at the tibia. Tibia bone strength and trabecular BMD were highest in females 16-19 years (p < 0.05), and tibia cortical porosity was lowest in females 16-19 years (p < 0.001). With the exception of an age-related increase in cortical BMD, all other parameters were stable between 16 and 29 years at the radius for both males and females. We found no peak values for males or females at the radius. At the tibia, a peak was observed for females 16-19 years.
  
  
  CONCLUSIONS
  These data provide a population-based assessment of bone microstructural and strength parameters from HR-pQCT and FEA in a youth cohort, showing clear differences in bone quality dependent on sex and skeletal site.
authors.affiliation: Department of Radiology, Faculty of Medicine, McCaig Institute for Bone and Joint Health, University of Calgary, Room HRIC 3C49, 3280 Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada, lburt@ucalgary.ca.
authors.forename: Lauren A
authors.initials: LA
authors.lastname: Burt
authors.forename: Heather M
authors.initials: HM
authors.lastname: Macdonald
authors.forename: David A
authors.initials: DA
authors.lastname: Hanley
authors.forename: Steven K
authors.initials: SK
authors.lastname: Boyd
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D015519:Bone Density / Q000502:physiology; D003430:Cross-Sectional Studies; D005260:Female; D020342:Finite Element Analysis; D006801:Humans; D008297:Male; D011884:Radius / Q000033:anatomy & histology / Q000502:physiology*; D012016:Reference Values; D017678:Sex Distribution; D013977:Tibia / Q000033:anatomy & histology / Q000502:physiology*; D055815:Young Adult