[Use of imaging procedures in the diagnostics of osteoporosis interpretation of x-rays and bone density measurements]. / Einsatz bildgebender Verfahren bei der Diagnostik der Osteoporose Interpretation der Röntgenbilder und Messprotokolle der Knochendichte.

According to the recently published BoneEVA study, 7.8 million Germans (6.5 million women) are affected by osteoporosis. Of them, 4.3% experienced at least one clinical fracture. Only 21.7% were treated with an anti-osteoporotic drug, whereby only 10% received a bisphosphonate and 17% given calcium and vitamin D. On the other hand, as osteoporosis may be associated with severe pain in 90% of patients, analgesics are prescribed. The total direct costs attributable to osteoporosis amounted to Euro 5.4 billion in 2003. One out of three postmenopausal women and one out of five men over the age of 50 years will experience osteoporotic fractures unless preventive measures are undertaken. According to the German guidelines for diagnosis and treatment of osteoporosis, bone densitometry using dual energy x-ray absorptiometry (DXA) together with other clinical risk factors (previous low trauma fracture, use of nicotine, low body weight [BMI<20 kg/m2], immobilisation, and more than two falls during the last six months) are recommended for diagnosis. Using typical cases out of clinical practice, this article delineates frequent mistakes in the interpretation of DXA measurements. Furthermore, the present paper clarifies the role of classical x-rays, which still represent the predominant procedure for the identification of fractures and especially vertebral fractures. In comparison to x-rays, CT or MRI are more important in differential diagnosis of malignant disease and bone metastases. Essentially a reduction of vertebral height without evidence of central endplate fracture in postmenopausal women may be unrelated to osteoporosis. Quantitative morphometry should not be used alone for the assessment of vertebral fracture in clinical decision-making. Therefore, we recommend differential diagnosis of morphometric vertebral deformities by an expert reader to rule out deformities related to degenerative disease and norm variants of which we will present several examples to train the view of the reader.

Prospective identification of postmenopausal osteoporotic women at high vertebral fracture risk by radiography, bone densitometry, quantitative ultrasound, and laboratory findings: results from the PIOS study.

Women with established osteoporosis are at high risk to sustain additional vertebral fractures. Treatment may affect the predictive power of bone densitometry and biochemical techniques. There are few prospective studies comparing fracture prediction by dual-energy X-ray absorptiometry (DXA) and other techniques in treated women with established osteoporosis. The objective of this study was to prospectively assess the predictive power of various DXA and quantitative ultrasound (QUS) techniques for identification of women at high risk to develop new fractures over 1-2 yr. Moreover, we wanted to investigate whether previous or ongoing therapy precluded the use of common clinical laboratory blood tests and bone turnover markers for prediction of fracture risk. We measured prevalent fracture status; bone mineral density (BMD) of the whole body, spine, and hip by DXA; QUS of the calcaneus and the patella; hormones and various markers of bone resorption and formation; and took standard blood tests in 124 women (age 64.9 yr +/- 7.9) with manifest and variously treated postmenopausal osteoporosis. Subsequently, new spine fractures were assessed after 1 yr and, in a subset of 87 women, after 2 yr. Prevalent fractures turned out to be the strongest predictor of subsequent vertebral fractures with an age-adjusted odds ratio (OR) of 3.9 per prevalent fracture over 2 yr. Furthermore, our results underline the predictive power of spinal BMD (sOR = 2.1; standardized OR per 1 standard deviation population variance decrease), whole body BMD (sOR: 2.4), and QUS stiffness index of the calcaneus (sOR: 2.8) for vertebral fracture prediction. QUS of the patella did not predict vertebral fractures. Blood sedimentation rate was predictive in the first year (sOR: 1.9). The predictive power of bone turnover markers, however, appeared to be too low to be detectable in a group of this sample size and it may have been reduced because most women were already receiving treatment. In conclusion, radiographic measures, but not the tested laboratory bone turnover markers, enabled us to identify women (from a population of osteoporotic women who have been treated for some time with a variety of medications) who are at highest risk for developing new vertebral fractures within 1-2 yr.