Measurements

Question 1

Sella turcica measurements and AKA

Answer 1

• pituitary fossa size

16 mm max S-I
Max 12 mm a-p

Question 2

indications for sella turcica size abnormal

Answer 2

pituitary neoplasm
extra pituitary neoplasm
aneurysm
may be normal

Question 3

Basilar angle AKA

and normal limits

Answer 3

Welcker’s/Martin’s/ sphenobasilar angle

• normal 123-152
  avg 137
  greater than 152 is platybasia

Question 4

McGregor’s line

Answer 4

aka basal line

- measure hard palate to inferior surface of occiput- relationship to odontoid apex

Question 5

Chamberlain’s line

Answer 5

AKA palatoccipital line

- hard palate to opisthion- odontoid apex

Question 6

McCrae’s Line

Answer 6

AKA foramen Mafnum line
- basion to opisthion and relationship of occiput and ondontoid
inferior margin of occiput should lie at or below line
- perpendicular through odontoid apex should intersect 1/4

may indicate atlanto- occipital joint dislocation or odontoid fracture

Question 7

list the lines for the skull

Answer 7

• sella turcica
• basilar angle
• McGregor’s line
• Chamberlain’s line
• Macrae’s line
• diagastric
• high index of klaus
• boogard’s line

Question 8

ADI

Answer 8

aka predental interspace / atlas- dens interval

• posterior margin of anterior tubercle and anterior cortical surface or odntoid at the mid portion of the joint
• 1-3 mm in adults
• 1-5 in children
• trauma, occipitalization
• trisomy 21
• pharyngeal infections (grisel’s disease)
• seronegative arthropathies

Question 9

contour lines

Answer 9

• four bony one soft tissue
• george’s line
  spinolaminal line
• posterior spinous

Question 10

Canal size

Answer 10

min 16 and 14 at C1 and C2 respectively
- from C3 through C7 should be > 13mm
Pavlov’s ration

Question 11

stress lines

Answer 11

aka ruth jackson line

• post surface of the C2 body
• post surface at C7 body
• flexion - should intersect C5-6

Question 12

prevertebral space

Answer 12

• retro- pharyngeal , laryngeal and tracheal interspace
• C2-C4 max , 22mm
• post traumatic hematoma
• retro-pharyngeal abscess and neoplasm

Question 13

list the lines for cervicals

Answer 13

• prevertebral spce
• stress lines
• canal size
• contour lines
• ADi

Question 14

Cobb- Lippmann

Answer 14

most relaible method of scoliosis evaluation

- determines therapeutic considerations of obersvation, bracing, surgery

Question 15

Risser ferguason

Answer 15

scoliosis evaulation method not often used

Question 16

Lumbosacral angle

Answer 16

aka sacral base angle / ferguson’s angle

• line through sacral base and second lilne parallel to film bottom
• posterior angle measured range 26- 57 / avg 41

Question 17

Disc angle

Answer 17

measured on lateral film

• L1- L5 , 8, 10 , 12 , 14
• may assist in distinguishing origins of low back pain, increased angle facet syndrome , particularly L5

Question 18

Gravity Line

Answer 18

AKA ferguson’s weight / gravitational

• center of L3 body and vertical line centered through and relationship to sacrum (upper)
• line should pass through the sacral base but can be up to 10 mm anterior to sacral promontory
• may increase weight bearing forces on apophyseal joints

Question 19

Macnab’s line

Answer 19

• inferior endplate line and relationship to tip of superior articular processes of the vertebra below
• line should lie above the tip of adjacent superior articular process
• if positive indicates facet imbrication/ subluxation and may be associated with facet syndrome but requires clinical correlation

Question 20

Hadley’s S curve

Answer 20

• on oblique and AP lumbar radiographs
• curvilinear line constructed alone inferior margin of TP and down along inferior articular process to apophyseal joint space cont across articulation to superior articular process
• interruption of line indicates facet subluxation

Question 21

Meyerding’s

Answer 21

• method of spondylolisthesis grading
• grades 1-4
• spondyloptosis - when slips completely off sacral base

Question 22

Ulmann’s line

Answer 22

AKA GArland - thomas line/ right angle test line

• first line is parallel to and through sacra; promontory
• the second line is perpendicular through sacral promontory
• • L5 should be posterior
• can use at any lumbar level

Question 23

canal size

Answer 23

• eisenstein’s method go sagital canal

- posterior sagital measurement should be > 15mm

Question 24

intercrestal line

Answer 24

on AP lumbar
- transverse line connecting the iliac crest and the relationship of L4 and L5 bodies and disc space to this line

• may be useful for predicting the level at which the most biomechanics stresses occurring in the lumbar spine in the level at which disc degeneration is most likely to occur