Osteoporosis Overview
Osteoporosis is a thinning of bone tissue and loss of bone density over time. It is the most common type of bone disease affecting an estimated 10 million Americans and represents a significant health risk to 55% of the population over the age of 50. Women are four times more likely to develop this disease; it is estimated that one in five women will suffer from osteoporosis in their lifetime.(1,2)
Osteoporosis, meaning “porous bone,” occurs when there is an imbalance between new bone formation and old bone resorption. The body may fail to form enough new bone, too much old bone may be reabsorbed, or both. The two essential minerals for normal bone formation are calcium and phosphate.
Throughout youth, the body uses calcium and phosphate to produce strong, healthy bones. If viewed under a microscope the structure of healthy bone looks like a dense honeycomb. When the body does not get enough calcium, or if it does not absorb enough calcium from the diet, bone production and bone tissues may suffer.
As the body ages, calcium and phosphate may be reabsorbed back into the body from the bones, making the bone tissue weaker. When this occurs, the spaces in the honeycomb become much larger, bones lose density or mass, and the structure of the bone tissue changes. This decrease in bone mass and change in bone architecture reduces the strength of the skeletal system resulting in brittle, fragile bones.
Comparison of Healthy Bone vs. Osteoporotic Bone
Osteoporosis is often called the “silent disease” because the disease itself produces no symptoms. Usually, bone loss occurs gradually over many years and the disease can be present without any symptoms for decades until a bone breaks (fractures). Women can lose up to 20 percent of their bone mass in the five-to-seven years after menopause, making them more susceptible to osteoporosis. (3 ,4 ,5)
While any bone can be affected by osteoporosis, fractures of the hip and spine are of particular concern. Bones that are affected by osteoporosis fracture with relatively minor injury that normally would not cause a healthy bone to fracture. A minor fall or, in serious cases, a simple action such as a sneeze can cause an osteoporotic bone to fracture. The fracture can be either in the form of cracking (as in a hip fracture) or collapsing (as in a compression fracture of the vertebrae of the spine). It is estimated that there are 700,000 osteoporosis related vertebral compression fractures each year in the US alone.(1)
Additional information:
National Osteoporosis Foundation: www.nof.org
North American Spine Society: www.knowyourback.org
Society of Interventional Radiology: www.sirweb.org
