Skorn Ponrartana1, Patricia C Aggabao1, Naga L Dharmavaram1, Carissa L Fisher1, Philippe Friedlich2, Sherin U Devaskar3, Vicente Gilsanz4. 1. Department of Radiology, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA. 2. Department of Pediatrics, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA. 3. Department of Pediatrics, Mattel Children's Hospital, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA. 4. Department of Radiology, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA; Department of Pediatrics, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA. Electronic address: vgilsanz@chla.usc.edu.
Abstract
OBJECTIVE: To examine whether the sex-related differences in vertebral cross-sectional area (CSA) found in children and at the timing of peak bone mass-a major determinant of osteoporosis and future fracture risk-are also present at birth. STUDY DESIGN: Vertebral CSA, vertebral height, and intervertebral disc height were measured using magnetic resonance imaging in 70 healthy full-term newborns (35 males and 35 females). The length and CSA of the humerus, musculature, and adiposity were measured as well. RESULTS: Weight, body length, and head and waist circumferences did not differ significantly between males and females (P ≥ .06 for all). Compared with newborn boys, girls had significantly smaller mean vertebral cross-sectional dimensions (1.47 ± 0.11 vs 1.31 ± 0.12; P < .0001). Multiple linear regression analysis identified sex as a predictor of vertebral CSA independent of gestational age, birth weight, and body length. In contrast, the sexes were monomorphic with regard to vertebral height, intervertebral disc height, and spinal length (P ≥ .11 for all). There were also no sex differences in the length or cross-sectional dimensions of the humerus or in measures of musculature and adiposity (P ≥ .10 for all). CONCLUSION: Factors related to sex influence fetal development of the axial skeleton. The smaller vertebral CSA in females is associated with greater flexibility of the spine, which could represent the human adaptation to fetal load. Unfortunately, it also imparts a mechanical disadvantage that increases stress within the vertebrae for all physical activities and increases the susceptibility to fragility fractures later in life.
OBJECTIVE: To examine whether the sex-related differences in vertebral cross-sectional area (CSA) found in children and at the timing of peak bone mass-a major determinant of osteoporosis and future fracture risk-are also present at birth. STUDY DESIGN: Vertebral CSA, vertebral height, and intervertebral disc height were measured using magnetic resonance imaging in 70 healthy full-term newborns (35 males and 35 females). The length and CSA of the humerus, musculature, and adiposity were measured as well. RESULTS: Weight, body length, and head and waist circumferences did not differ significantly between males and females (P ≥ .06 for all). Compared with newborn boys, girls had significantly smaller mean vertebral cross-sectional dimensions (1.47 ± 0.11 vs 1.31 ± 0.12; P < .0001). Multiple linear regression analysis identified sex as a predictor of vertebral CSA independent of gestational age, birth weight, and body length. In contrast, the sexes were monomorphic with regard to vertebral height, intervertebral disc height, and spinal length (P ≥ .11 for all). There were also no sex differences in the length or cross-sectional dimensions of the humerus or in measures of musculature and adiposity (P ≥ .10 for all). CONCLUSION: Factors related to sex influence fetal development of the axial skeleton. The smaller vertebral CSA in females is associated with greater flexibility of the spine, which could represent the human adaptation to fetal load. Unfortunately, it also imparts a mechanical disadvantage that increases stress within the vertebrae for all physical activities and increases the susceptibility to fragility fractures later in life.
Authors: Judith L Ross; Charmian A Quigley; Dachuang Cao; Penelope Feuillan; Karen Kowal; John J Chipman; Gordon B Cutler Journal: N Engl J Med Date: 2011-03-31 Impact factor: 91.245
Authors: Alessandra Chesi; Jonathan A Mitchell; Heidi J Kalkwarf; Jonathan P Bradfield; Joan M Lappe; Diana L Cousminer; Sani M Roy; Shana E McCormack; Vicente Gilsanz; Sharon E Oberfield; Hakon Hakonarson; John A Shepherd; Andrea Kelly; Babette S Zemel; Struan Fa Grant Journal: J Bone Miner Res Date: 2017-03-02 Impact factor: 6.741
Authors: Skorn Ponrartana; Carissa L Fisher; Patricia C Aggabao; Thomas A Chavez; Alexander M Broom; Tishya A L Wren; David L Skaggs; Vicente Gilsanz Journal: Pediatr Radiol Date: 2016-05-16
Authors: Tuija M Mikkola; Mikaela B von Bonsdorff; Clive Osmond; Minna K Salonen; Eero Kajantie; Johan G Eriksson Journal: J Bone Miner Res Date: 2017-03-02 Impact factor: 6.741
Authors: Tishya A L Wren; Patricia C Aggabao; Ervin Poorghasamians; Thomas A Chavez; Skorn Ponrartana; Vicente Gilsanz Journal: PLoS One Date: 2017-02-28 Impact factor: 3.240
Authors: D Manousaki; F Rauch; G Chabot; J Dubois; M Fiscaletti; N Alos Journal: J Musculoskelet Neuronal Interact Date: 2016-09-07 Impact factor: 2.041