Radiographic Lines of Mensuration Flashcards
Sella Turcica dimensions:
AP, what is the normal and upper limit size?
12mm - 16mm
Sella Turcica dimensions:
Vertical view, what is the average and upper limit of size?
8-12mm
What can cause empty sella syndrome, pituitary tumor, macroadenoma, and craniopharyngioma?
Enlargemnet of sella turcica
What is the McGregor line (basal line)?
Direct line from posterior tip of hard palate to lowest point of occipital bone
McGregor line (basal line): Odontoid process should not pass this line by more than \_\_\_\_\_ in males, \_\_\_\_\_ females.
(M) 7-8mm
(F) 10mm
McGregor line (basal line) is most accurate measure for __________impression in rheumatoid arthritis, other bone softening conditions.
Invagination/basilar
What is the Chamberlain line?
It connects posterior hard palate with posterior margin of foramen magnum
Chamberlain line:
_____ should not pass this line <4mm can be normal.
Odontoid process
What is the Macrae line?
It connects anterior-posterior foramen magnum.
Macrae line:
Should always remain more _____ to lowest-most tip of occiput
superior
What is the Digastric line?
A line connecting bases of the Mastoid processes: C2 Dens should not project above this line
Power’s ratio is for _____ dissociation.
Atlanto-occipital
Power’s ratio:
Distance between the basion and the
posterior spinolaminar line of C1 divided by the distance between the A arch of C1 and the opisthion. Should always be __.
< 1 (Less than 1)
Another useful measurement of the craniocervical junction is the “Rule of 12”. Meaning that the basion-to-dens interval should not measure greater than ___and compared to
basion-to-Axis interval also measuring at less than ___
12-mm
If basio-axial interval is greater than 12mm suggest _____ and _____ injury.
Atlanto-occipital dislocation and ligamentous injury
What conditions can increase the atlantodental interspace (ADI)?
Instability (RA, inflammatory, Down Syndrome, Grisel syndrome-pharyngeal infection spread)
In CHILDREN, the Atlantodental interspace (ADI) should be ___.
<5mm
In ADULTS, the Atlantodental interspace (ADI) should be ___.
<3 mm
Atlantodental interspace (ADI) is considered NORMAL at ___.
2 mm
What is the BALLOONING OF SELLA?
Widened pituitary fossa
PLATYBASIA: Martin’s angle is usually greater than ___ degrees.
> 152 degrees
Basilar scull angle/Martin’s angle aka Welcker basilar angle, sphenobasilar angle should be WITHIN ___ degrees.
125-143 degrees
On APOM view, lateral masses of C1 should be aligned with C2.
If C1 lateral masses overhang C2 by ___ combined then transverse ligament disruption is considered
6-mm
Prevertebral soft tissues in adults in general should remain less than ___ at C2 and less than ___ at C6-C7
7-mm; 22-mm
Cobb Method: utilizes superior_____ of upper most vertebra and inferior _____ of lower most vertebra of the scoliotic curvature
end-plate
_____ method to evaluate abnormal kyphosis or lordosis
Cobb
Line connecting T8 anterior body to posterior sternum should not be <13-cm in males and 11-cm- females. Straight back syndrome diagnosis.
<13-cm; <11-cm- females
Normal angles of spinal discs at L4- L5= __-degree
14
Lumbar lordosis can be measured by _____ method
Cobb
Lumbar gravity line L3-centre should intersect sacral base this line is known as?
Ferguson gravity line
_____ line should intersect the superior articular process of the vertebra below
Macnab
_____measure of lumbar instability may indicate degenerative disc and facet changes and associated instability
Van Akkerveeken (Air; dark spot can be visible in intervertebral joint space)
_____ classification of spondylolisthesis grading: Grade 1-4
Myerding
Interpedicular distance: Normal distance at L4 is ___
27-mm
Widening of interpedicular distance (<24mm) can suggest what syndromes?
Marfan syndrome and Elhers- Danlos syndrome
Eisenstein Method of AP sagittal canal dimensions: Normal spinal canal at lower lumbar region should remain no less than _____
14-mm.
Klein line is important in evaluating for _____
Slipped capital femoral epiphysis (SCFE)
Kohler teardrop can be used as reference point to evaluate abnormal distance_____difference from the contralateral hip (Waldenstrome sign)
> 2-mm
An estimate of acetabular hypoplasia or overcoverage. Consider developmental dysplasia of the hip
Centre-edge angle.
Centre-edge angle:
- Normal=
- Moderate dysplasia=
- Severe dysplasia=
> 15 degrees
-Between 15 and 5 degrees
<5 degrees
Femoral (inclination) angle evaluation to evaluate traumatic or atraumatic causes of _____ or _____
Coxa Vara or Valga
-Femoral shaft line perpendicular to
tip of greater trochanter line
-The fovea should lie above or at the level of “trochanter line”
What is this known as?
Skinner line
Acetabula angle in infant
12-29- degrees; 20-degrees average
Increase and decrease in Acetabula angle would results in?
- Increase = congenital hip dysplasia
- Decreased = down syndrome
_____: a line connecting bony pelvic inlet with the outer aspect of the obturator foramen.
Kohler’s line
If the floor of the acetabulum cross Kohler’s line it may signify ______
Protrusio Acetabuli
Presacral soft tissue space (adults average: _____, children: _____),
5-7-mm; 3-5- mm
Widening of Presacral soft tissue space >___, consider Sacral trauma/fracture and hematoma
20-mm
Symphysis pubis distance: Males-___, females- ___
6-mm; 5-mm
Bohler’s angle: evaluate fractures of the _____ and _____
calcaneus and talus
-Line from posterior articular surface calcaneus to anterior articular process of calcaneus
-Posterior process to superior angle of calcaneus tuberosity
(These forms what angle?)
Bohler’s angle
Soft tissue heel pad (range ______). Thickening of heel pad is often associated with _____
19-23-mm; Acromegaly
Glenohumeral joint space is evaluated on _____ view.
AP external rotation view
What is the average measurement of GHJ space?
4-5 mm
Acromiohumeral articulation space ranges between _____
7-11 mm
Reduced Acromiohumeral articulation space indicate _____ tear or other causes of instability.
rotator cuff
AC joint: ranges_____ normal. If less than consider osteoarthritis
3-8-mm
Terry Thomas Sign indicates?
Scapholunate dislocation
Scapholuante space should remain no more than _____.
3-4-mm
