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The most widely used scoring method is the SQ grading system introduced by
Genant et al. [
27
]. Osteoporotic vertebral fractures are graded on visual inspection
and without direct vertebral measurement: grade 0: normal, grade 1: mildly
deformed (approximately 20
25 % reduction in anterior, middle, and/or posterior
height and a reduction of area 10
-
20 %), grade 2: moderately deformed (approx-
-
imately 25
40 %), and
grade 3: severely deformed (approximately 40 % reduction in any height and area).
Furthermore, the spinal fracture index (SFI) can be calculated by summing the
individual vertebral body grades. The advantage of SQ methods is the relatively
little time needed for performing the grading. The disadvantage of the SQ methods
is the lower reproducibility and worse objectivity compared to the QM grading
systems. In contrast to the ABQ method, the Genant scoring system does not
account for several other important characteristics of vertebral fracture including
endplate deformity or buckling of cortices.
The ABQ method uses a scheme to systematically rule out non-fracture defor-
mities [
28
]. Osteoporotic vertebral fractures are diagnosed based on the assumption
that these fractures always involve the fracture of the endplate. Thus, the evidence
of endplate fracture and not the variation in vertebral shape is the primary indicator
of osteoporotic fracture. The advantage of the ABQ method is the better differen-
tiation of true fractures from non-fracture deformities, in contrast to the QM and SQ
scoring systems where no allowance is made for variation in vertebral dimensions
at different vertebral levels or short vertebral heights associated with Scheuer-
mann
40 % reduction in any height and a reduction in area 20
-
-
is disease, scoliosis etc. A skilled reader is needed for the ABQ method to
differentiate accurately between vertebral fractures and non-fracture deformities,
which is a disadvantage compared to the QM and SQ scoring systems.
Radiography of the thoracic and lumbar spine is the standard imaging modality
used for the initial assessment of osteoporotic vertebral fractures (Fig.
2
). The dose
from a lateral radiograph of the thoracic and lumbar spine is about 0.6 mSv [
29
].
Vertebral Fracture Assessment (VFA) by using newer generations of DXA
scanners allows for imaging of the thoracic and lumbar spine to assess prevalent
osteoporotic vertebral fractures [
30
,
31
]. It can be combined with the DXA-based
BMD measurements which is advantageous. VFA has lower radiation exposures
than radiographs with reported doses in the range from 0.002 to 0.05 mSv [
29
].
Moderate and severe osteoporotic fractures can be accurately identi
'
ed by VFA,
but caution is necessary when vertebrae are evaluated in the presence of degener-
ative changes of the spine [
32
]. In these cases, radiographs with their superior
spatial resolution allow the detection of more subtle abnormalities. Furthermore,
Buehring et al. reported that VFA is dependent on instrument and reader [
33
].
Multi-detector computed tomography (MDCT) and magnetic resonance imaging
(MRI) allow for a 3D visualization of the spine and are used as advanced diagnostic
tools for osteoporotic fractures [
34
]. Both imaging techniques are substantially
more expensive than radiography. Compared to MDCT, MRI has the advantage
that it lacks ionizing radiation. Bone marrow edema can be detected by using MRI.
Its presence can differentiate a recent from an old osteoporotic vertebral fracture
(Fig.
3
). In contrast to MRI, the integrity and shape of the vertebrae, particularly the
