What is an insufficiency fracture? My mother was told that’s what’s causing her new knee pain.

Insufficiency fracture is a small subset of a larger group of fractures called
stress fractures. Insufficiency fractures are caused by the effect of normal stress
on weakened bone. Osteoporosis is the most common cause of bone loss leading to
insufficiency fractures.

Loss of bone density from osteoporosis decreases the bone’s ability to “give” slightly
and resist everyday loads. The loss of this “elasticity” seems to affect the spine, tibia
and fibular (lower leg bones) and calcaneus (heel) most often.

These fractures seem to be on the rise in older adults, especially postmenopausal women.