Lines Flashcards
(30 cards)
Sella Turcica
AKA pitutiary fossa size
greatest AP 16mm
greatest vertical 12mm
may indicate pituitary neoplasm, extra pituitary neoplasm, aneurysm or normal
basilar angle
Welcker's/ Martin's/sphenobasilar angle bone softening pathology nasion to center of sella and basion Normal= 123-152 avg 137 measure greater than 152*= platybasia congenital or acquired
McGregors line
AKA basilar line
hard palate to inferior surface of occiput-relationship to odontoid apex
chamerlains line
AKA palatooccipital line
hard palate to opisthion- odontoid apex
MaCrae’s line
AKA foramen Magnum line
basion to opisthion and relationship of occiput and odontoid
inferior margin of occiput should lie at or below line
perpendicular through odontoid apex should intersect ant 1/4
indication for platybasia
ADI
AKA predental interspace, atlas-dens interval
posterior margin of anterior tubercle and anterior cortical surface of odontoid
1-3mm adults; 1-5mm kids up to puberty
may have “V” configuration in flexion and inverted “V” in extention
Trauma
occipitalization
trisomy 21
pharyngeal infections (Grisel’s disease)
seronegative arthopathies
acromegaly
contour lines
4 bony; 1 soft
anterior body
posterior body (george’s line)
spinolaminal (most reliable)
posterior spinous (least reliable esp cervical)
Must all break in the same direction unless loss of intrasegmental structural osseous integrity
canal size cervical
min 16 and 14 at C1 and C2
C3-C7 >13
Pavlovs (canal body) ratio
Stress line
AKA Ruth Jackson lines
posterior surface of C2 body, posterior surface at C7 body
flex intersection C5-6 disc/factes
ext C4-5disc/facets
clinical significance has not been established
prevertebral space
retro-pharyngeal, laryngeal, tracheal interspace
C2-4= max 7mm
C5-7 max= 22mm
Cobb-Lippman
most reliable method of scoliosis evaluation
measure determine therapeutic consideration of observation, bracing, surgery
Risser-Ferguson
scoliosis eval not often used
gen 25% lower than Cobb’s method
Lumbosacral angle
AKA sacral base, Fergusons angle
line through sacral base and second line parallel to film bottom
posterior angle is measured range of 26-57* avg= 41* in upright position
clinical significance questionable
better when combined other measurements
disc angles
measured on lateral lumbar film
L1-5; 8, 10, 12, 14, 14
may assist in distinguishing origins of LBP
increased angles in facet syndrome particularly L5
Gravity Line
AKA Fergusons weight-bearing/gravitational line
Center L3 body and vertical line centered through and relationship to upper sacrum
upright or recumbent seems irrelevant
line should pass through sacral base but can be up to 10mm anterior to sacral promontory
may indicate increased weight-bearing forces on apophyseal joints
Macnab’s Line
inferior endplate line and relationship to tip of superior articular process of vertebra below
line should lie above the tip of adjacent superior articular process
if + indicates facet imbrication/subluxation and may be associated with facet syndrome but requires clinical correlation and significance is questionable
Hadley’s S curve
on oblique and AP lumbar
curvilinear line constructed along inferior margin of TP and down along inferior articular process to apophyseal joint space continuing across the articulation to connect with outer edge of opposing superior articular process
interruption of line indicates facet subluxation
Meyerdings
spondylolisthesis grading
sacral base divided 1-4
spondyloptosis when slips completely off sacral base
percentage method of Taillard slippage in % millimetric mensuration is absolute slippage in mm
Ulmann’s line
AKA Garland-Thomas Line, Right angle test line
lateral lumbar line parallel to and through sacral base and second line perpendicular through sacral promontory
anterior margin of L5 body should be posterior or just contact the perpendicular line
can be used at any lumbar level
Canal Size in lumbars
Eisensteins method of sagittal canal measurement
articular process line constructed connecting the tips of the superior and inferior articular processes at each lumbar level
measurement is at the midportion of the posterior vertebral body
provides sagittal canal measurement= >15mm
intercrestal line
AP lumbar transverse line connecting the iliac crest and the relationship of the L4 and 5 bodies and disc spaces to this line
useful for predicting the level at which the biomechanical stresses occurring in the lumbar spine in the level at which disc degeneration is most likely to occur
most stable position is intersection through the bottom half of the L4 disc/body
Length of TP
AP lumbar vertical line through tip of L3 TP laterally
relationship of L5 TP to this line
short L5 TP may indicate structural instability at the lumbosacral junction use with intercrestal line
Kohlers line
acetabular protrusion
line constructed tangential to cortical margin of pelvic inlet and lateral border of obturator foramen- acetabular floor should not cross this line and should lie lateral
Shenton line
AKA Menard/Makka’s line
curvilinear line from superior obturator continuing to medial femoral neck–> should be unborken
indicated hip dislocation, femoral neck fracture and SCFE
