Potential Sex Differences in Bone Strength: A Cadaveric Study

Abstract

This study was conducted to determine if there was a difference in bone strength between men and post‐menopausal women. Prior research suggests that women are four times more likely to be affected by osteoporosis and experience fractures twice as often as men. Bone mass loss found in osteoporosis increases in women after menopause due to marked estrogen deficiency. However, it is unclear whether this bone mass difference between men and women contributes to a reduction in bone strength. Therefore, the hypothesis of this study was that men will have a higher bone density than women and will therefore have stronger bones when tested to failure. To test this hypothesis, eight cadavers (four men, four women) from the Wayne State University Willed Body Program were used (age: 81±16, range: 51‐104). The bone density of the ulna was calculated via a volume displacement test and its mass. The ulna was then secured and weight was added incrementally until failure. There was no significant difference found in ulna bone density between men and women (p=0.776); however, the weight required to break the ulnas in men was greater (p=0.0001). Once normalized by the mass of the ulna this effect was reduced (p>0.05). These data suggest potential sex differences in bone strength, independent of bone density, indicating future investigation is needed at different locations in the body.