Understanding DEXA scan results can be a bit confusing. Basically, the test will tell you how much bone loss has occurred. This information will determine if you have osteoporosis and give an estimate on what your chances are of breaking a bone.
After the age of 40, bone mass (particularly calcium) begins to decline in both men and women, about 2% loss per year. As bone loss occurs, the bones become fragile (the bone mineral density, BMD, is low). The thinner they get, the more easily they can break.
Osteopenia is a medical condition when BMD is lower than normal, but not low enough to be osteoporosis (although it is considered by some to be a precursor to osteoporosis).
Osteoporosis is a disease in which the bones become very porous and are subject to fracture. Osteoporosis is uncommon in men, mainly because their bone mass is greater than women before the age of 40 and they do not go through menopause. If a male has osteoporosis, it is most likely due to an underlying condition such as long-term use of corticosteroids or hyperparathyroidism.
Postmenopausal osteoporosis is the most common type and although the whole skeleton may be involved, bone loss is normally greatest in the ribs, spine, and hips.
A DEXA scan (low-dose radiation x-ray) is the best device to use when measuring BMD because it provides the most accurate results, even with minimal loss (unlike a regular x-ray).