A bone densitometer (in this case the iDXA) measures bone mineral density (BMD). The amount of bone mineral relates directly to bone density. The bone densitometer uses minimal doses of x-ray to measure BMD and to produce images of the spine, hips, or even the whole body. The technical term for the method is “dual-energy x-ray absorptiometry”, or DEXA. The spine and both hips are always measured because that is where osteoporotic fractures most commonly occur.
Like other organs in the body, bones are constantly changing. Throughout childhood and young adulthood, bones grow in strength and in size. Around the age of 30, bones reach their peak strength and then naturally become weaker with age. Osteoporosis is a condition where bones become weak to the point of breaking. This weakening may be due to aging, or caused by other factors that combine with age. Symptoms of osteoporosis do not occur until a lot of bone strength is lost. The most visible symptoms may include loss of height, along with curvature of the upper back. Osteoporosis also can result in a crippling and painful fracture, occurring most often in the hip, back, or wrist.