Osteoporosis (porous bones) is a progressive bone disease that is characterized by a decrease in bone density with an increased risk of fractures. Osteoporosis is defined by the World Health Organization (WHO) as a bone mineral density of 2.5 standard deviations or more below the mean peak bone mass (average of young, healthy adults) as measured by dual-energy X-ray absorptiometry. The most common form of osteoporosis occurs in women after menopause. Senile osteoporosis occurs after age 75 and is seen in both females and males at a ratio of two to one. Secondary osteoporosis occurs at any age and affects men and women equally. Chronic predisposing medical problems or prolonged use of medications such as glucocorticoids cause secondary osteoporosis. A number of medications can increase the risk of osteoporosis.

The main problem associated with osteoporosis is the risk for bone fractures. In the elderly, osteoporosis can be associated with chronic pain due to fractures and can lead to further disability and early mortality. Fractures of the wrist, spine, shoulder and hip are the most common. Vertebral compression fractures are associated with back pain and shooting pain due to nerve root compression. Rarely will spinal cord compression occur and be life-threatening. Multiple vertebral fractures can lead to a stooped posture, loss of height and chronic pain with resultant reduction in mobility. Fractures of the long bones, such as hip fracture, require prompt surgery.