radiographic lines

Radiographic LinesSkull – 4

• Sella turcica• Basilar Angle• McGregors line• Chamberlains line

McGregor sells chamberlains bass 4 skulls.

Cervical – 9• Cervical Lordosis• Stress lines of cerv. Spine• Cervical gravity Line• Georges line• ADI• Posterior cervical line• Sagital dimension of cerv. Spinal canal• Atlanto Axial Alignment• Pre-vertebral soft tissue

9 cervical Lords stress gravity GAPS AAAnd pre-vertebral soft tissue

Radiographic LinesThoracic – 4

• Riser-Ferguson (SC)• Thoracic cage dimension• Cobb’s Angle (SC)• Thoracic Kyphosis

Riser-Ferguson Caged Cobb’s Kyphosis

Lumbar – 12• Inter-vertebral Disc Height• Lumbar inter-vertebral disc angles• Lumbar lordosis• Lumbo-sacral angle• Lumbo-sacral disc angle• Hadley’s S curve• Vanakkerveekens measurement of lumbar

instability• Lumbar gravity line • Static vertebral malposition• Lateral Bending sign• Ullman’s Line• Meyerding Rating System

ILLLL HVL SLUM

Radiographic LinesLower Ext – 15

• Boehler’s angle• Klein’s Line• Skinners line• Center edge angle/ Wiberg’s• Hip joint space• Acetabular angle• Pre-sacral space• Symphysis pubis width• Heel Pad Measurement• Patellar malalignment• Iliac angle and index• Protrusio acetabuli / Kohler’s line• Shenton’s line• Ilio femoral line• Femoral Angle

Boehlers use CKlein on their Skin, not their CHAPS, heel, or patella, IPSIlateral for Females

Upper Ext – 5• Glenohumeral joint space• Metacarpal sign• Acromiohumeral joint space• Acromiclavicular joint space• Radio-capitellar line

Glen Met Acromio Humer & Acromio Clavi over the Radio

SkullSella turcica size

– 5mm to 16mm– Avg is 11mm– Pituitary masses

can cause enlargement

SkullBasilar Angle

– Avg. 137 degrees– 123 to 152 degrees– Basilar impression and

platybasia widen angle• Nasion to sella turcica

to basion• Beyond 152 degrees

platybasia, could be congenital or caused by paget’s

SkullMcGregors line

– Males: 8mm– Females: 10mm– Basilar impression when

odontoid more than maximum distance above

– Caused by atlas occipitalization, platybasia, and bone softening such as paget’s or osteomalacia

• Hard palate to occiput– Note relative odontoid apex

SkullChamberlains line

– Basilar impression when odontoid more than maximum distance above

– Hard Palate to opisthion– Caused by atlas

occipitalization, platybasia, and bone softening such as paget’s or osteomalacia

CervicalCervical Lordosis

– Role is unclear. Decreased following trauma, muscle spasm, spondylosis, and patient tucking the chin at time of exposure.

CervicalStress Lines of

Cervical Spine– Flexion C5-C6 joint– Extension C4-C5 joint– Go through C2 and C7

vertebral bodies and note intersection

– Muscle spasm, joint fixation, and/or disc degeneration may decrease

CervicalCervical Gravity Lines

– Vertical line from odontoid apex

– Passes through C7 body

CervicalGeorges Line

– Alignment of posterior body margins

– A to P vertebral mal-positions when line not smooth

– Such as fractures, dislocation, anterolisthesis or retrolisthesis

CervicalAtlantoDentalInterspace (ADI)

– C1 anterior tubercle – odontoid

– Adult 1mm-3mm– Child 1mm-5mm– Transverse ligament

rupture or instability. Trauma, Down’s, and inflammatory arthritis may increase the measurement

CervicalPosterior Cervical Line

– Spinolaminar junction lines

– AP vertebral malposition when line is not smooth, especially at C1 and C2

CervicalSagittal Dimension of

the cervical spine– Posterior body-

spinolaminar junction.– 12mm minimum– Spinal stenosis when less

than 12mm. Intraspinal tumor when enlarged.

CervicalAtlanto Axial Alignment

– C1 lateral mass-C2 articular pillar margin alignment

– Jefferson’s or odontoid fractures or alar ligament instability when margins overlap

CervicalPrevertebral Soft tissue

– Anterior bodies-posterior air shadow margins

– Retropharyngeal 7mm• C2,3,4

– Retrolaryngeal 7-20mm• C4,5

– Retrotracheal 20mm• C5,6,7

• Soft tissue masses (tumor, infection, hematoma) increase the measurements

Thoracic• Riser-ferguson

– Centers of end and apical segments joined and the angle measured

– Used for Scoliosis Evaluation

ThoracicThoracic Cage

– Posterior sternum-anterior T8 body

– Male: 14cm– Female: 12cm

• Straight back syndrome when the distance is less than 13cm in males and 11cm in females

ThoracicCobb’s Angle

– End vertebral endplate lines then intersecting perpendiculars and the angle measured.

– Used for scoliosis evaluation

ThoracicThoracic Kyphosis

– T1 superior endplate-T12 inferior endplate, then intersecting perpendiculars and the angle measured

– Used for Kyphosis evaluation (Scheuermann’s fractures)

LumbarIntervertebral Disc

Height– Hurxthal method (A) –

endplate to endplate– Farfan Method (B) – Ant

Height divided by disc diameter, posterior height divided by disc diameter, then as ratio to each other

• If decreased, then DJD, surgery, infection

Lumbar

Lumbar Inter-vertbral disc angles– At each disc endplate

lines are drawn and the angles measured

• Altered in various pathologies

LumbarLumbar lordosis

– L1 endplate–S1 endplate; perpendiculars and angle formed

– 50-60 degrees• Altered in various

pathologies

LumbarLumbosacral angle

– Endplate of S1 to horizontal line angle

– 41 degrees is average– 26-57 degree range

• Altered in various pathologies

LumbarLumbosacral Disc Angle

– Angle between opposing endplates of L5 and S1

– 10-15 degree range• Altered in various

pathologies

LumbarHadley’s “S” curve

– A line along the inferior surface of the TVP, AP and across the joint

– Should be smooth• Facet subluxation

could be present if “S” is Broken

LumbarVan akkerveekens

measurement of lumbar instability– Endplate lines are opposing

segments. Measure from the posterior body to the point of intersection

– Should be equal measurements– Max is 1.5 mm difference

• Nuclear, annular and posterior ligament damage if more than 1.5 mm difference

LumbarLumbar Gravity Line

– A perpendicular line is drawn from the center point of the L3 body

– Intersects sacral base• Altered in various

pathologies

LumbarStatic Vertebral

malposition / Houston conference listings / medicare listings– Numerous terms are

applied to describe static vertebral malpositions

• Altered in various pathologies

LumbarLateral Bending Sign

– Spinous position– Intersegmental

wedging– Usually toward

concavity– Gradually increase

away from sacrum• Disc herniation at

level failing to laterally flex

LumbarUllman’s Line

– Endplate line through S1, perpendicular from sacral promontory

– L5 should be behind the line

• Detection of subtle spondylolisthesis when L5 body crosses perpendicular line

LumbarMeyerding Rating

System– Sacral base divided

into quarters. Relative position of the posterior body of L5 is made.

• Grading severity of spondylolisthesis

Percentage Method/Anterolisthesis

• The displacement between the posterior sacral base and the posterior aspect of L5 vertebrais measured along a plane paralleling the disc in millimeters

• The measured displacement is then divided by the length of the sacral promontory and multiplied by 100

• The main advantage is the removal of any geometrical magnification

Lower ExtremityKlein’s Line

– Tangential line to outer femoral neck. Head just overlaps laterally

• Slipped epiphysis suspected if head does not intersect line.

Lower ExtremityBoehler’s angle

– Three superior points joined on the calcaneus, posterior angle is measured

– Avg. 30-35 degrees– 28-40 degrees is the

range• Calcaneal fractures

may reduce the angle to less than 28 degrees

Tear Drop Distance

• Distance between the most medial margin of the femoral head and the outer cortex of the pelvic tear drop is measured

• Average: 9, Minimum: 6, Maximum: 11• Probably early Legg-Calve-Perthes,Septic

arthritis

Tear Drop Distance

Lower ExtremitySkinner’s line

– Femoral shaft line. Perpendicular second line tangential to the tip of the greater trochanter

– Passes through or below fovea capitus

• Hip joint abnormality if line passes above fovea capitus

Lower ExtremityCenter edge Angle /

Wiberg’s– From the center of the

femoral head, vertically and acetabular edge, lines are drawn.

– The angle is then measured

– Avg. 36 degrees– 20-40 degrees is range

• A shallow acetabulum may precipitate DJD

Lower Extremity

Hip Joint Space– Femoral head-

acetabulum distance– Superior = 3-6mm– Axial = 3-7mm– Medial = 4-13mm

• Various joint diseases increase the space– DJD, RA,

Degenerative RA

Lower ExtremityAcetabular Angle

– Y-Y line drawn. Second line from medial to lateral acetabular surfaces. Angle measured

– Avg. 20 degrees– 12-29 degrees is the range

• Congenital hip dislocation widens the angle.

• Down’s syndrome decreases the angle

Lower Extremity• Pre-sacral space

– Soft tissue density between the rectum and anterior sacral surface

– Child: 3mm (1-5)– Adult: 7mm (2-20)

• Diastasis and inflammatory joint disease may widen the joint.

Lower Extremity• Symphysis Pubis

Width– The distance between

opposing articular surfaces, Halfway between the superior and inferior margins

– Male:6mm (4.8-7.2)– Female: 5mm (3.8-6.0)

• Diastasis and inflammatory joint disease may widen the joint.

Lower ExtremityHeel Pad Measurement

– Shortest distance between the calcaneus and plantar skin surface

– Male: 19mm – 25mm– Female: 19mm – 23mm

• Acromegaly produces skin overgrowth exceeding the max measurement

Lower ExtremityPatellar mal-alignment

– Patella length-patella tendon ratio

– 1:1• Chondromalacia

patellae factor if the ratio is exceeded more than 20%

Lower ExtremityIliac Angle and index

– Y-Y line drawn. Second line along lateral iliac wing and iliac body

– Sum of right and left iliac and acetabular angles divided by 2

– Avg. 68 degrees • 60 to 80 degrees is possible

sign of Down’s syndrome• Probable Down’s if below 60

degrees

Lower Extremity / HIPProtrusio Acetabuli /

Kohler’s Line– Pelvic inlet-outer

obturator. Acetabulum should be lateral to the line

• Could be Paget’s disease when acetabulum is medial to the line

Lower ExtremityShenton’s line

– Smooth curvilinear line along ilium and onto femoral neck and superior obturator border

• Femur dislocation or fracture if line is interrupted

Lower ExtremityIliofemoral line

– Smooth curvilinear line along ilium and onto femoral neck

– Should be bilaterally symmetrical

• Asymmetry may denote hip joint abnormality

Lower ExtremityFemoral Angle

– Lines through the femoral shaft and neck

– 120-130 degrees is the range

• Coxa vara: less than 120 degrees

• Coxa Valga: Greater than 130 degrees

Upper ExtremityGlenohumeral joint space

– Average humeral head-glenoid distance (superior, middle, inferior)

– 4-5 mm• Degenerative and crystal

arthritis diminish the space. Posterior dislocation may widen it.

Upper ExtremityMetacarpal sign

– Tangential line through the fourth and fifth metacarpal heads. Third head should be proximal to this line

• Turners Syndrome, post fracture deformity

Upper ExtremityAcromiohumeral joint

space– Acromion-humeral head– Avg. 9mm – 7mm-11mm is the range

• Rotator cuff tear decreases distance.

• Subluxation and dislocation increase the distance

Upper ExtremityAcromioclavicular joint

space– Avg. acromion-clavicular

distance (superior, inferior)– Male: 3.3mm (2.5-4.1mm)– Female: 2.9mm (2.1-

3.7mm)• Degenerative arthritis will

decrease distance• Separation and resorption

will widen distance

Upper ExtremityRadio-capitellar line

– Radius axis line through the elbow joint

– Passes through capitellar center

• Radius subluxation/dislocation if line misses the capitellar head