How is osteoporosis defined?

Osteoporosis is a disease that affects your bones, weakening them, making them more likely to break. Low bone mass is a main characteristic of osteoporosis. Osteoporosis is often called the “silent thief” because bone loss can occur without you even knowing it or feeling anything. This bone loss does not occur overnight but over the course of several years. Sometimes the first sign anything is wrong is a broken bone.

The most common types of osteoporotic breaks are those occurring in the spine, hip and wrist.

Bone mineral density (BMD) tests are safe and painless, and measure the density or thickness of your bones. Small amounts of x-rays are transmitted through your bones. The amount passing through is measured. The greater the amount passing through, the less dense your bones. If you have had your BMD tested, you may have heard your doctor refer to your “T-score.” The T-score is a measuring system used to compare the bone density of an individual to that of a group of young adults of the same sex. A T-score indicates the number of units (standard deviations) a person’s bone density is above or below the standard. The higher the T-score, the denser the bone. According to the World Health Organization, a T-score between +2.5 and -1 is considered normal; a T-score between -1 and -2.5 indicates osteopenia (low BMD); and a T-score below -2.5 indicates osteoporosis.