A new direction for osteoporosis research: a review and proposal.

This article suggests why drugs that only reduce the activity of existing osteoclasts or enhance the activity of existing osteoblasts probably cannot cure the osteopenias associated with most osteoporoses. Instead they should add only limited amounts of bone, which should begin to disappear after treatment stops. That behavior depends on these facts. Different threshold ranges of mechanical bone strains control gains and losses of bone mass. One threshold controls gains by modeling drifts, and a lower one controls losses by remodeling BMUs. A drug that does not change those thresholds should limit gains (or losses) of bone during indefinitely continued treatment. Success in curing those osteopenias should require learning how to change the thresholds.