Prior to the introduction of the first dedicated bone
densitometry unit in the 1970s, physicians primarily used
one of two methods to assess bone density. One was the
to tally subjective reading of X-rays based upon individual
radiologist experience and the presence or absence of
certain markers, such as the fine spicules, called
"trabecula, that form a network in cancellous bone."
While the absence o f trabecula may mean 30% to 50%
bone loss, it is fa r from precise. Clearly, a better way to
assess bone density was needed.