Osteoporosis, which means "porous bone," is a disease characterized by low bone mass and structural deterioration of the bone tissue. This leads to bone fragility and an increased susceptibility to fractures of the hip, spine and wrist.
In the United States today, 10 million people already have the disease and 18 million more have low bone mass (osteopenia), which places them at risk for osteoporosis. For good reason, osteoporosis is often called the "silent disease." That's because bone loss occurs without symptoms. People may not even know that they have osteoporosis until their bones become so weak that a sudden strain, bump or fall causes a break or causes a vertebra to collapse.
Special bone density tests can, however, measure bone density in various sites of the body. A bone density test can also detect osteoporosis before a fracture occurs, as well as predict your chances of fracturing in the future and determine your rate of bone loss. The test can likewise monitor the effects of treatments.