What Is It?
Osteoporosis is a disorder of the bones characterized by decreased bone mass (generalized thinning of the bones), which also decreases bone strength. Because weakened bones are more fragile and more likely to break, people with osteoporosis are at increased risk of fractures, especially fragility fractures (broken bones that happen with little or no trauma). It is not a form of arthritis, although it can cause fractures that, in turn, lead to arthritis.
In the United States, osteoporosis causes more than 1.3 million fractures annually and is much more common in women than in men. The most common first fracture is a wrist fracture, which typically occurs between ages 50 and 70 in women. Hip fractures and fractures of the spine (compression fractures) are also common, especially among people who are in their 70s. Osteoporosis can cause a great deal of suffering, including loss of independence or even death, particularly when the fracture involves the hip.
Most people with osteoporosis have no symptoms and are totally unaware that they have the problem. One early sign can be a loss of height caused by curvature or compression of the spine, which is caused by weakened vertebrae (spine bones). The weakened vertebrae undergo compression fractures — tiny breaks that cause the spine bones to collapse vertically. When this happens, the height of the vertebrae is decreased, and the shape of each single vertebra goes from a normal rectangle to a more triangular form. Although the loss of height caused by compression fractures sometimes can be associated with back pain or aching, more typically it is does not cause any symptoms.
Osteoporosis usually does not cause pain unless there has been a fracture. When there is no sign of a fracture, pain in the bones or joints is probably caused by another problem, such as arthritis (a disorder that affects the cartilage lining the joints), tendonitis (inflammation of the tendons), or a disorder of the muscles or connective tissues. In a similar way, although back pain sometimes can be caused by osteoporotic fractures, other common causes of back pain include arthritis, a pulled muscle or problems in the disks between vertebrae.
When taking your history, your doctor will look for factors that increase your risk of osteoporosis. These risk factors include:
- Being female
- Being age 40 or older
- Being a postmenopausal woman
- Having a diet low in calcium or an intestinal problem that prevents absorption of calcium and vitamins
- Having an overactive thyroid (hyperthyroidism)
- Leading a sedentary lifestyle, with little or no routine exercise
- Being thin
- Taking certain medications, such as prednisone
- Having a certain ethnic background (people who are Caucasian or of Asian descent are more at risk of osteoporosis than are African-Americans)
- Using alcohol to excess
- Having a family history of osteoporosis
- Having a history of at least one fragility fracture
On physical examination, your doctor may find that you are shorter than you thought you were or that you have a “dowager’s hump,” a curve of the spine in the upper back that produces a prominence. On X-rays, your bones may be less dense than expected, a sign of osteopenia (diminished bone on an X-ray). Although most cases of osteopenia are caused by osteoporosis, there are other causes such as too little mineral in bone (called osteomalacia) as a result of inadequate intake or absorption of vitamin D.
Osteoporosis should be suspected strongly in any person who has a fragility fracture. It also can be established by a bone-density test. There are several techniques available to measure bone density. The most complete and accurate method is DEXA (dual-energy X-ray absorptiometry), which is the best for both diagnosing osteoporosis and assessing response to treatment. DEXA is a quick (10 to 15 minutes) and painless test that uses minute amounts of radiation (less than dental X-rays) and is generally done on the spine and hip. A newer method, ultrasound bone density of the heel, is even quicker and less expensive, but it is not yet widely available or accepted as an accurate screening test for osteoporosis. Usually, people who are found to have osteoporosis by heel ultrasound eventually go on to have DEXA of the spine and hip.
Bone-density tests can diagnose osteoporosis when the condition is mild and you do not have any symptoms, and can help lead to treatment that will prevent the condition from getting worse. In people with loss of height or suspicious fractures, bone-density tests not only confirm the diagnosis of osteoporosis, they also serve as a baseline for treatment and can be used to follow the response to therapy. Once identified, additional blood and urine tests may be recommended to identify a cause of osteoporosis. However, for most women, no clear cause (other than age and being postmenopausal) is found.
Although osteoporosis is a chronic (long-term) condition, proper treatment can result in significant improvements in bone mass and can decrease the likelihood that symptoms will appear. Even though bone mass does not generally return to normal, the risk of fracture may decrease dramatically (often by 50 percent or more) after several years of treatment.
You can help prevent osteoporosis by taking adequate calcium and vitamin D, by following a routine program of weight-bearing exercise, by not smoking and by avoiding excess alcohol consumption. Many physicians routinely recommend 500 to 1,000 milligrams daily of extra calcium (for example, in the form of calcium carbonate, as in Tums, and in many other inexpensive forms) or even more if your diet is particularly low in calcium or if you are nursing. Similarly, it may be appropriate to take a daily multivitamin that contains vitamin D.
If you are a woman who has entered menopause, you should speak with your doctor about evaluation and treatment for osteoporosis, such as estrogen-replacement therapy, raloxifene (Evista) alendronate (Fosamax) or risedronate (Actonel). A bone-density test for osteoporosis may make the decision easier if it shows signs of a problem. Because the loss of height caused by osteoporosis-related compression fractures may not cause any other symptoms, it is also a good idea to measure your height annually, especially if you are a woman older than age 40.
Another measure to help prevent osteoporosis is regular monitoring of thyroid medication if you take it, because too much of this medication may lead to osteoporosis and other medical problems. If you take prednisone for any reason, work with your doctor to reduce the dose to its lowest possible amount or even to discontinue the medication.
Doctors treat osteoporosis by prescribing adequate intake of calcium and vitamin D, by recommending a program of routine weight-bearing exercise and by modifying other risk factors. In addition, several effective medications are available. For women, estrogen-replacement therapy, alendronate (Fosamax), risedronate (Actonel), raloxifene (Evista) and nasal calcitonin (Miacalcin) are all effective treatments for osteoporosis approved by the U.S. Food and Drug Administration. Given the risks that may be associated with long-term estrogen therapy, many physicians prefer one of the other options as a first choice. Among men, a low level of testosterone is the most common cause, so for male patients with osteoporosis, this is among the first tests. If testosterone levels are low, evaluation for the cause and treatment with testosterone is generally recommended. Other, nonhormonal options are available for men as well, including alendronate and raloxifene.
Finally, a form of parathyroid hormone, teriparatide (Forteo) recently was approved for treating osteoporosis. This medication is given by a daily injection under the skin. It will probably be reserved for the worst cases of osteoporosis that have failed to respond to other treatments, but its precise role is not yet clear. For people who experience problems or side effects with other treatments, additional agents are available, including etidronate (Didronel), or pamidronate (Aredia). Treatment progress is monitored by bone-density measurements performed every one to two years. To allow for the most accurate comparison, all bone-density measurements should be performed on the same machine in the same facility.
When an osteoporotic hip fracture occurs, surgery may be necessary. A wrist fracture may do well with casting alone, or surgery may be needed. Other treatments for fracture include pain medication and rest for a short time. Calcitonin injections may reduce spine pain from a new compression fracture.
When To Call A Professional
If you have risk factors for osteoporosis, or if you have a fracture with minimal or no trauma, review your options for evaluation and treatment with your doctor.
The prognosis for osteoporosis is good, especially when it is detected and treated early. Bone density, even in severe osteoporosis, generally can be stabilized or improved, and the risk of fracture can be reduced by 50 percent or more after several years of treatment. People with mild osteoporosis have an excellent prognosis. Those who have already experienced osteoporotic fractures generally can expect their bones to heal normally and pain to generally resolve within a week or two. The prognosis is improved when a reversible cause, such as prednisone use, is identified and stopped under your doctor’s supervision. If proper treatment is begun and tolerated, most patients can effectively prevent osteoporosis from developing or improve it once it has started.
Diseases and Conditions Center
All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.