Oct. 25, 2011 Osteoporosis is blamed for backbone fractures. The
real culprit could well be our own vertebrae, which evolved to
absorb the pounding of upright walking, researchers at Case
Western Reserve University say. Compared to apes, humans have
larger, more porous vertebrae encased in a much thinner shell of
bone. The design works well until men and women age and suffer
bone loss, leaving them vulnerable to cracks and breaks, the
scientists say. Apes, on the other hand, can suffer comparable
bone loss as they age, but have much thicker vertebral shells to
begin with so that their vertebrae remain intact. The findings
are now published in the online journal PLoS ONE. "In evolution
we have great adaptation, but there is sometimes a tradeoff,"
said Meghan Cotter, an instructor in anatomy at Case Western
Reserve University School of Medicine and a lead author of the
study. "The structure is great for walking around, but not good
when you have osteoporosis," she said. Cotter worked with former
master's studen