Thoracic vertebrae
Antero-posterior (Basic)
Position of patient and image receptor
● The patient is positioned supine on the X-ray table, with the median sagittal plane
perpendicular to the tabletop and coincident with the midline of the Bucky.
● The upper edge of the image detector should be at a level just below the prominence of
the thyroid cartilage to ensure that the upper thoracic vertebrae are included.
Direction and location of the X-ray beam
● The vertical collimated beam is centred at right-angles to the image receptor and
towards a point 2.5 cm below the sternal angle
Essential image characteristics
● The image should include the vertebrae from C7 to L1.
● The image density should be sufficient to demonstrate bony detail for the upper as well
as the thoracic lower vertebrae.
Lateral (Basic)
Position of patient and image receptor
● The examination is usually undertaken with the patient in the lateral decubitus position
on the X-ray table, although this projection can also be performed erect
● The median sagittal plane should be parallel to the image receptor The arms should be
raised well above the head.
● The head can be supported with a pillow, and pads may be placed between the knees
for the patient’s comfort.
● The upper edge of the image detector or cassette should be at least 40 cm in length
and should be positioned 3–4 cm above the spinous process of C7.
Direction and location of the X-ray beam
The collimated vertical beam should be at right-angles to the long axis of the thoracic
vertebrae. This may require a caudal angulation. Centre 5 cm anterior to the spinous process
of T6/7.
Essential image characteristics
● The upper two or three vertebrae may not be demonstrated due to the superimposition
of the shoulders.
● ensure that T12 has been included within the field.
● The posterior ribs should be superimposed, thus indicating that the patient was not
rotated too far forwards or backwards.
● The trabeculae of the vertebrae should be clearly visible
● The image density should be adequate for diagnosis for both the upper and lower
thoracic vertebrae
Lumbo-sacral junction
Lateral
Position of patient and image receptor
● The patient lies on either side on the Bucky table, with the arms raised and the hands
resting on the pillow.
● The knees and hips are flexed slightly for stability.
● The image receptor is centred at the level of the 5th lumbar spinous process.
Direction and location of the X-ray beam The collimated vertical beam is centred at right-angles
to the lumbo-sacral region and towards a point 7.5 cm anterior to the 5th lumbar spinous
process
If the patient has particularly large hips and the spine is not parallel with the tabletop, then a 5°
caudal angulation may be required to clear the joint space. Essential image characteristics
The area of interest should include the 5th lumbar vertebra and the first sacral segment. A
clear joint space should be demonstrated.
Antero-posterior
Position of patient and image receptor
● The patient lies supine on the Bucky table, with the median sagittal plane coincident
with, and perpendicular to, the midline of the Bucky
● The knees can be flexed over a foam pad for comfort and to reduce the lumbar lordosis
The image receptor is displaced cranially so that its centre coincides with the central ray
Direction and location of the X-ray beam
● The collimated central beam is directed 10–20° cranially from the vertical and towards
the midline at the level of the anterior superior iliac spines
● The degree of angulation of the central ray is normally greater for females than for
males and will be less for a greater degree of flexion at the hips and knees
Essential image characteristics
The image should be collimated to include the 5th lumbar and first sacral segment.
Right or left posterior oblique
Position of patient and image receptor
● The patient is positioned supine on the Bucky table and is then rotated to the right and
left sides
● The hips and knees are flexed and the patient is supported with 45° foam pads placed
under the trunk on the raised side.
● The image receptor is displaced cranially at a level to coin�cide with the central ray .
Essential image characteristics
● The posterior elements of L5 should appear in the ‘Scottie dog’ configuration.
