@article{ref1,
title="Sex differences in parameters of bone strength in new recruits: Beyond bone density",
journal="Medicine and science in sports and exercise",
year="2008",
author="Evans, Rachel K. and Negus, Charles and Antczak, Amanda J. and Yanovich, Ran and Israeli, Eran and Moran, D. S.",
volume="40",
number="11 Suppl",
pages="S645-53",
abstract="BACKGROUND: Stress fracture (SF) injuries in new recruits have long been attributed to low bone mineral density (BMD). Low areal BMD assessed using two-dimensional dual-energy x-ray absorptiometry imaging, however, reflects structural density and is affected by smaller measures of bone geometry. Recent studies support a relationship between bone size and SF and indicate that slender bones are more susceptible to damage under identical loading conditions. Peripheral quantitative computed tomography (pQCT) is a three-dimensional imaging tool that provides measures of tissue density and geometry parameters of the tibia, a common site of SF. PURPOSE: To evaluate sex differences in parameters of volumetric BMD (vBMD), geometry, and strength of the tibia in new recruits using a novel pQCT image analysis procedure. METHODS: pQCT images were obtained from 128 healthy men and women (20 male, 108 female, aged 18-21 yr) entering a 4-month gender-integrated combat training program in the Israeli Defense Forces. Tibial scans taken at sites 4% (trabecular bone), 38%, and 66% (cortical bone) from the distal end plate were analyzed using MATLAB to assess whole-bone and regional parameters. Measures included vBMD, geometry (diameter, area, cortical thickness, and canal radius), and strength (moments of inertia and bone strength and slenderness indices). RESULTS: With the exception of normalized canal radius, which did not differ between sexes, all measures of bone geometry (P<0.0001) and strength (P<0.0001 to P = 0.07) were greater in men. Women exhibited 2.7% to 3.0% greater cortical vBMD than men, whereas trabecular vBMD was 8.4% lower in women (P<0.001). These differences remained significant after adjusting for body size. CONCLUSION: Sex differences in bone geometry and mineralization of the tibia may contribute to a decreased ability to withstand the demands imposed by novel, repetitive exercise in untrained individuals entering recruit training.<p /> <p>Language: en</p>",
language="en",
issn="0195-9131",
doi="10.1249/MSS.0b013e3181893cb7",
url="http://dx.doi.org/10.1249/MSS.0b013e3181893cb7"
}