Osteoporosis - Weakness of Bone

Osteoporosis

Osteoporosis is a skeletal disorder characterized by compromised bone strength, which predisposes to increased risk of fractures. Contrary to other common diseases that produce distinct symptoms, osteoporosis can exist undetected for a longtime before complications like bone fractures, height loss and bending of spinal column occur.

A woman left untreated is predicted to have a 50% chance of suffering from an osteoporotic fracture sometime in her life. In addition to spinal fractures, common fracture locations include the wrist (hand), ankles (foot),and hip. Thus, it is important that physicians and patients take measures to prevent and treat the disease.

Bone is in a constant state of turnover or activity throughout life. The basic pathology in osteoporosis is an imbalance between bone resorption and bone formation. The most common cause of this imbalance is menopause (stop of periods).The peak bone mass is reached, at the age of 20 to 30 years.

After peak bone mass is reached, the bone remodeling process is in a state of equilibrium until menopause. Stop of menstrual period sleads to rapid bone loss of approximately to half of the total spinal bone mass.

This is then followed by a slower rate of bone loss(0.5%/year), which is related to aging due to decrease in physical activity and there are other secondary cause for osteoporosis.

Osteoporosis - Weakness of Bone

Various techniques are available to quantify bone mass, but the most accurate and precise is the central dual-energy x-ray absorptiometry (DXA) scan. A strong correlation exists between fracture risk and bone density.

The World Health Organization (WHO) criteria are the widely accepted basis for osteoporosis diagnosis. Osteoporosis was defined as a T-score equal to or less than -2.5. T-scores above this cutoff but below -1.0 define osteopenia, or low bone mass. Normal BMD is 1 SD above or below the mean (T-score of -1 to +1). An individual who has a T-score of -2.5 or less and has suffered from an osteoporotic fracture is considered to have severe or established osteoporosis. Clinicians therefore, incorporate Bone Mineral Density (BMD), age, and prior fracture in their assessment of fracture risk and patient management to improve their bone health.

Successful treatment of osteoporosis requires a careful choice of blood and urine tests to determine the presence of secondary causes of osteoporosis like liver, kidney, bowel disease, hormone imbalance and cancer.

Osteoporosis therapies are designed to improve bone strength and reduce the risk for fracture. Treatment of osteoporosis is with drugs which can be taken by mouth (daily or monthly) or once in a year if given intravenously through blood. Drugs for osteoporosis can be divided into two major classes: anti-resorptive and anabolic agents. Within a few weeks of starting therapy,  patients will usually report an improvement in clinical symptoms like alleviation of bone pain, improvement in muscle strength, and possibly increased sense of well-being.

Greater decrease in blood and urine markers of bone resorption and increase in bone strength after initiation of treatment. Thus it is possible to predict a reduction in fracture risk in response to therapy within months of initiation of treatment.

There may be an improvement in Bone Mineral Density (BMD) in the spine and hip even within just 1 year of treatment. All patients should be counseled on exercises. The benefits of exercise include improved muscle strength, gait, and balance, and better sense of well-being.

Here, the concept is that if Bone Mineral Density (BMD) continues to decline over the patient lifetime, the risk for fracture is greater as the patient gets older. Thus earlier intervention reduces the lifetime risk of fracture.