lines of alignment Flashcards
what does the acronym AllABCS stand for?
All: all details, films, anatomy, artefacts and adequacy
A: alignment
B: bone quality; trabecular pattern, density, medullary cavities, cortical continuity/thickness/integrity
C:cartilage-joint space and symmetry
S: soft tissues; densities (inflammation, bleeding, necrosis), viscera
what are 5 cervical x-ray views? what is this set of series called?
- APOM
- AP lower cervical
- lateral
- rt and lt oblique post
- flex and extension lateral
Davis Series
list 10 lines of cervical alignment
- ALL
- PLL
- SLL
- Spinal Canal Width
- Cervical angle
- Physiological line of stress (Ruth Jackson)
- Vertical line of stress (COG)
- ADI
- Retropharyngeal line
- Retrotracheal line
2 methods of pedicle rotation
2 methods of scoliosis
- spinous method
- pedicle method (most accepted method)
- Cobb Lippman Method
- Risser-Ferguson Method
what are the 3 views of thoracic x-rays
- AP
- Lateral
- Specific Rib views
list 7 thoracic lines of alignment
- pedicle rotation
- interpedicular distance
- ALL
- PLL
- SLL
- angle of thoracic spine
- scoliosis
What level does the trachea bifurcate in an adult?
T6
what 4 x-ray views can be ordered in the LS region?
AP
Lateral
oblique rt and lt
L5/S1 spot view (AP and Lat)
list 10 lines of alignment relevant to the LS region
- ALL
- PLL
- SLL
- lumbar curve angle
- Fergusons Line (lumbar gravitational line)
- Meyerding (lx spondylolisthesis)
- Ulman’s (lx spondylolisthesis)
scoliosis, rotation and interpedicular distance
list 8 lines of alignment for the pelvis
- acetabular depth
- symphysis pubis width
- femoral angle
- ilio-femoral line
- Shenton’s line
- Skinner’s line
- Klein’s line
- Hip joint width (teardrop distance); sup, medial, axial
list 5 x-ray views of the knee
- AP
- Lateral
- Intercondylar
- skyline
- medial oblique
what is the normal cervical spinal canal width?
C4-7 12-22mm
<12mm is stenosis
how is cervical angle measured and what is the normal lordosis?
midpoints of ant and post tubercles of atlas and a line through inferior endplate of C7. perpendiculars are constructed if required.
normal=35-45deg normal lordosis
how is the cervical physiological line of stress (Ruth Jackson) measured and what should the point pass through in neutral, flexion and extension?
line passing through posterior aspect of dens and line through posterior aspect of C7.
neutral-through C4/5 IVD
flexion-C5/6
extension-C4/5 posterior
how is the vertical line of stress (COG) measured in the cervical spine?
line pass through apical aspect of C2 and a line passing through anterior/superior aspect of C7
how is ADI measured?
what is the normal distance for adults and for children?
what conditions can affect this?
- anterior aspect of dens and post aspect of ant tubercle of C1.
- adults 1-3mm; children 1-5mm
- inflammatory arthridities (PARRS), Downs Syndrome; can lead to rupture of transverse ligament
what is the vertebral level and what is the normal measurement of the retropharyngeal and retrotracheal lines?
retropharyngeal=C2; <5mm
retrotracheal=C6; <20mm
what are the 4 basic parameters investigated in scoliosis?
- curvature
- rotation
- flexibility
- skeletal maturation
what is the normal lumbar curve angle?
35-45 deg
method 1: horizontal line to sup endplate L1, and horizontal line to inferior endplate L5.
method 2. same as above but second line is horizontal at superior sacral base.
how is Ferguson’s line measured?
AKA lumbar gravitational line
perpendicular line dropped from the centre of L3
should strike anterior margin of the normal ant 1/3 of the sacral base
what are the normal measurements in M and F for acetabular depth, symphysis pubis width and femoral angle?
acetabular depth: M=13mm, F=18mm
symphysis pubis width: M=6mm, F=5mm
femoral angle=120-130 deg
what are the 4 x-ray views for the pelvis and hip?
AP widely collimated
Spot AP hip
Frogleg
Lateral (uncommon due to superimposition)
how is angle of thoracic spine measured?
line drawn parallel to superior endplate of T1 (or T4) and inferior endplate of T12 (T9). drop perpendicular lines if necessary; 20-50 degrees normal kyphosis
