[Clinical application of densitometry]

An early diagnosis of osteoporosis and an accurate estimation of treatment outcome are the focus of the radiological efforts. The most commonly applied methods for the evaluation of the peripheral and axial skeleton are dual x-ray absorptiometry, quantitative computed tomography, and quantitative ultrasound. Data of an individual are generally compared to an age-, sex-, and ethically-matched control population. The bone mass measurement predict a patients future risk of fracture and the presence of osteoporosis can be diagnosed even in the absence of prevalent fractures. Fracture risk increases approximately 1.5-2.5 times for every 1.0 standard deviation an individual's bone mass is below the mean peak mass of healthy young individuals (T-score). The choice of the appropriate measurement sites may vary depending on the specific circumstances of the patient. The choice of the appropriate technique in any given clinical circumstance should be based on the strength and limitations of the different techniques.