The diagnostic string quintet of osteoporosis
Until recently, the diagnosis of osteoporosis was equated with or reduced to bone density measurements. The WHO definition, which defines osteoporosis via the T-Score exclusively via the result of the bone density measurement, has contributed significantly to this not very happy development. In retrospect, that was regrettable, because bone density is only one small stone in a larger mosaic that characterizes this disease – just as a violin alone does not make up a string quintet. In the past, bone density measurement could still play the role of the first violin in the diagnostic string quintet of osteoporosis due to the lack of other options, whereas the other instruments were medical history, physical examination, laboratory and X-ray examinations (comparable to the 2nd violin, viola and cello in a string quintet ) but have always been just as necessary components of a thorough diagnosis. After all, the focus is always on the person as a whole and we do not want to treat a measured value, but rather a person with an illness that needs treatment. As a rule, this one-sided restriction of osteoporosis diagnostics to bone density measurement is still common practice today, but this will certainly change fundamentally in the next few years.
Bone density, which used to be the main instrument of osteoporosis diagnostics, has had its day, even if many doctors who deal with osteoporosis diagnostics and osteoporosis therapy have not yet noticed it. The new definition of osteoporosis accordingly focuses on bone strength! In this new definition, bone density measurement only plays a very subordinate role. Other factors such as 3D microarchitecture, quantitative structural parameters, bone geometry, mineralization, material properties and bone metabolism (bone turnover) are much more decisive for assessing bone strength or for assessing the risk of fractures (risk of bone fractures) than the bone density, which is determined with the common DXA method. Method cannot even be measured correctly! With the virtual bone biopsy with the Xtreme-CT, we are now able to measure a large part of these more important factors in vivo, ie directly on the patient without any intervention in a short time, completely painlessly and with only a low level of radiation exposure, and thus make much more accurate statements about to determine the individual condition of the bone or the individual risk of bone fracture and thus also the necessity of a possibly necessary drug treatment than was only possible with the simple “bone density measurement” until recently!
Also, the “bone density measurement” with the still widespread DXA method (which cannot measure real bone density) is, contrary to the earlier opinion, only very limited due to new, fundamentally different findings, the actual bone fracture risk (and nothing else is involved in the diagnosis of osteoporosis) judge! Simple bone density measurements are also hardly useful for evaluating therapy or progress.
A thorough diagnosis of osteoporosis today should therefore include at least the following 5 points:
- Anamnesis (personal medical history, complaints, pain symptoms, etc.)
- Physical examination
- Laboratory examination (basic laboratory, if necessary extended laboratory)
- X-ray examination (if necessary)
- Bone structure analysis (formerly bone density measurement)
Because this new method (virtual bone biopsy in vivo) is currently still very little widespread, in Germany there are currently only 2 devices available for routine patient examinations (in Munich and Hamburg, as of May 2006), most patients unfortunately still have to be rely on the DXA measurement. Due to the significantly higher cost of this new examination, it will certainly be a few more years before this method becomes accessible to more patients. But Rome was not built in a day either, and there is justified hope that more such devices will be installed in the next few years.