Osteoporosis occurs when the imbalance in favor of bone loss becomes exaggerated. If the bone mass built up during adolescence has been insufficient, osteoporosis may also occur in the absence of abnormal bone loss later in life. Women are more prone to osteoporosis because of the rapid bone loss after menopause. Lack of estrogen, family history of osteoporotic fractures, small build, sedentary lifestyle, smoking and excessive alcohol use are important factors for the development of osteoporosis. Exposure to certain medications can also increase bone loss.
Bone loss causes no symptoms until a fracture occurs.
The fracture can occur spontaneously or after minimal trauma, depending on the severity of the disease. The most common sites for fractures are the forearm, the vertebrae and the hip. The diagnosis is made through clinical assessment by a physician with the help of radiologic studies. Plain x-rays can also detect low bone mass and fractures. The use of biochemical markers of bone metabolism in the blood and urine can also be useful for evaluating the results of therapy over time.