Osteoporosis is a condition characterized by a decrease in the density of bone, decreasing its strength and resulting in fragile bones. Osteoporosis literally leads to abnormally porous bone that is compressible, like a sponge. This disorder of the skeleton weakens the bone and results in frequent fractures (breaks) in the bones. Osteopenia is a condition of bone that is slightly less dense than normal bone but not to the degree of bone in osteoporosis.

Normal bone is composed of protein, collagen, and calcium, all of which give bone its strength. Bones that are affected by osteoporosis can break (fracture) with relatively minor injury that normally would not cause a 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). The spine, hips, ribs, and wrists are common areas of bone fractures from osteoporosis although osteoporosis-related fractures can occur in almost any skeletal bone.

What are osteoporosis symptoms and signs?
Osteoporosis can be present without any symptoms for decades because osteoporosis doesn't cause symptoms until bone fractures. Moreover, some osteoporotic fractures may escape detection for years when they do not cause symptoms. Therefore, patients may not be aware of their osteoporosis until they suffer a painful fracture. The symptom associated with osteoporotic fractures usually is pain; the location of the pain depends on the location of the fracture. The symptoms of osteoporosis in men are similar to the symptoms of osteoporosis in women.

Fractures of the spine (vertebra) can cause severe "band-like" pain that radiates from the back to the sides of the body. Over the years, repeated spinal fractures can lead to chronic lower back pain as well as loss of height and/or curving of the spine due to collapse of the vertebrae. The collapse gives individuals a hunched-back appearance of the upper back, often called a "dowager hump" because it commonly is seen in elderly women.

A fracture that occurs during the course of normal activity is called a minimal trauma, or stress fracture. For example, some patients with osteoporosis develop stress fractures of the feet while walking or stepping off a curb.

Hip fractures typically occur as a result of a fall. With osteoporosis, hip fractures can occur as a result of trivial slip-and-fall accidents. Hip fractures also may heal slowly or poorly after surgical repair because of poor healing of the bone.

What are the consequences of osteoporosis?
Osteoporotic bone fractures are responsible for considerable pain, decreased quality of life, lost workdays, and disability. Up to 30% of patients suffering a hip fracture will require long-term nursing-home care. Elderly patients can develop pneumonia and blood clots in the leg veins that can travel to the lungs (pulmonary embolism) due to prolonged bed rest after the hip fracture. Osteoporosis has even been linked with an increased risk of death. Some 20% of women with a hip fracture will die in the subsequent year as an indirect result of the fracture.

In addition, once a person has experienced a spine fracture due to osteoporosis, he or she is at very high risk of suffering another such fracture in the near future (next few years). About 20% of postmenopausal women who experience a vertebral fracture will suffer a new vertebral fracture of bone in the following year.

Why is osteoporosis an important public-health issue?
In the U.S., 44 million people have low bone density (10 million have osteoporosis, and 34 million haveosteopenia). This amounts to 55% of the U.S. population aged 50 years and older.
One in two Caucasian women will fracture a bone due to osteoporosis in her lifetime.
In the U.S., direct health-care costs from osteoporosis fractures amount to a billion dollars, without even taking into account the indirect costs, such as lost days at work and productivity.

Approximately 20% of those who experience a hip fracture will die in the year following the fracture.
One-third of hip-fracture patients are discharged to a nursing home within the year after fracture.
Only one-third of hip-fracture patients regain their pre-fracture level of function.
With the aging of America, the number of people with osteoporosis-related fractures will increase exponentially. The pain, suffering, and overall impact on health and economic costs will be enormous.

How is osteoporosis diagnosed?
A routine X-ray can reveal osteoporosis of the bone because the bones appear much thinner and lighter than normal bones. Unfortunately, by the time X-rays can detect osteoporosis, at least 30% of the bone has already been lost. In addition, X-rays are not accurate indicators of bone density. Thus, the appearance of the bone on X-ray often is affected by variations in the degree of exposure of the X-ray film.

The National Osteoporosis Foundation, the American Medical Association, and other major medical organizations recommend a dual-energy X-ray absorptiometry scan (DXA, formerly known as DEXA) be used for the diagnosis of osteoporosis. DXA typically measures bone density in the hip, the spine, and the forearm. The test takes only five to 15 minutes to perform, exposes patients to very little radiation (less than one-tenth to one-hundredth of the amount used on a standard chest X-ray), and is quite precise.
The bone density of the patient is compared to the average peak bone density of young adults of the same sex and race. This score is called the "T score," and it expresses the bone density in terms of the number of standard deviations (SD) below peak young adult bone mass.
Osteoporosis is defined as a bone density T score of -2.5 or below.

Osteopenia (between normal and osteoporosis) is defined as bone density T score between -1 and -2.5.
It is important to note that while osteopenia is considered a lesser degree of bone loss than osteoporosis, it nevertheless can be of concern when it is associated with other risk factors (such as smoking, cortisone steroid usage, rheumatoid arthritis, family history of osteoporosis, etc.) that can increase the chances for developing vertebral, hip, and other fractures. In this setting, osteopenia may require medication as part of the treatment program.

What is the treatment for osteoporosis, and can osteoporosis be prevented?
The goal of treatment of osteoporosis is the prevention of bone fractures by reducing bone loss or, preferably, by increasing bone density and strength.
Although early detection and timely treatment of osteoporosis can substantially decrease the risk of future fractures, none of the available treatments for osteoporosis are complete cures.
In other words, it is difficult to completely rebuild bone that has been weakened by osteoporosis. Therefore, prevention of
osteoporosis is as important as treatment.

The following are osteoporosis treatment and prevention measures:
Lifestyle changes, including quitting cigarette smoking, curtailing excessive alcohol intake, exercising regularly, and consuming a balanced diet with adequate calcium and vitamin D
Medications that stop bone loss and increase bone strength, such as alendronate (Fosamax), risedronate (Actonel), raloxifene(Evista), ibandronate (Boniva), calcitonin (Calcimar), zoledronate (Reclast), and denosumab (Prolia)
Medications that increase
bone formation such as
teriparatide(Forteo).

Source: www.medicinenet.com