Radiographic Lines Skull 4 Sella turcica Basilar Angle

Radiographic Lines • • Skull – 4 Sella turcica Basilar Angle Mc. Gregors line Chamberlains line • • Mc. Gregor 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 Lines • • Thoracic – 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 Lines • • • • Lower 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

Skull Sella turcica size – 5 mm to 16 mm – Avg is 11 mm – Pituitary masses can cause enlargement

Skull Basilar 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

Skull Mc. Gregors line – Males: 8 mm – Females: 10 mm – 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

Skull Chamberlains 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

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

Cervical Stress Lines of Cervical Spine – Flexion C 5 -C 6 joint – Extension C 4 -C 5 joint – Go through C 2 and C 7 vertebral bodies and note intersection – Muscle spasm, joint fixation, and/or disc degeneration may decrease

Cervical Gravity Lines – Vertical line from odontoid apex – Passes through C 7 body

Cervical Georges Line – Alignment of posterior body margins – A to P vertebral malpositions when line not smooth – Such as fractures, dislocation, anterolisthesis or retrolisthesis

Cervical Atlanto. Dental Interspace (ADI) – C 1 anterior tubercle – odontoid – Adult 1 mm-3 mm – Child 1 mm-5 mm – Transverse ligament rupture or instability. Trauma, Down’s, and inflammatory arthritis may increase the measurement

Cervical Posterior Cervical Line – Spinolaminar junction lines – AP vertebral malposition when line is not smooth, especially at C 1 and C 2

Cervical Sagittal Dimension of the cervical spine – Posterior bodyspinolaminar junction. – 12 mm minimum – Spinal stenosis when less than 12 mm. Intraspinal tumor when enlarged.

Cervical Atlanto Axial Alignment – C 1 lateral mass-C 2 articular pillar margin alignment – Jefferson’s or odontoid fractures or alar ligament instability when margins overlap

Cervical Prevertebral Soft tissue – Anterior bodiesposterior air shadow margins – Retropharyngeal 7 mm • C 2, 3, 4 – Retrolaryngeal 7 -20 mm • C 4, 5 – Retrotracheal 20 mm • C 5, 6, 7 • Soft tissue masses (tumor, infection, hematoma) increase the measurements

Thoracic • Riser-ferguson – Centers of end apical segments joined and the angle measured – Used for Scoliosis Evaluation

Thoracic Cage – Posterior sternumanterior T 8 body – Male: 14 cm – Female: 12 cm • Straight back syndrome when the distance is less than 13 cm in males and 11 cm in females

Thoracic Cobb’s Angle – End vertebral endplate lines then intersecting perpendiculars and the angle measured. – Used for scoliosis evaluation

Thoracic Kyphosis – T 1 superior endplate. T 12 inferior endplate, then intersecting perpendiculars and the angle measured – Used for Kyphosis evaluation (Scheuermann’s fractures)

Lumbar Intervertebral 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 Inter-vertbral disc angles – At each disc endplate lines are drawn and the angles measured • Altered in various pathologies

Lumbar lordosis – L 1 endplate–S 1 endplate; perpendiculars and angle formed – 50 -60 degrees • Altered in various pathologies

Lumbar Lumbosacral angle – Endplate of S 1 to horizontal line angle – 41 degrees is average – 26 -57 degree range • Altered in various pathologies

Lumbar Lumbosacral Disc Angle – Angle between opposing endplates of L 5 and S 1 – 10 -15 degree range • Altered in various pathologies

Lumbar Hadley’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

Lumbar Van 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

Lumbar Gravity Line – A perpendicular line is drawn from the center point of the L 3 body – Intersects sacral base • Altered in various pathologies

Lumbar Static Vertebral malposition / Houston conference listings / medicare listings – Numerous terms are applied to describe static vertebral malpositions • Altered in various pathologies

Lumbar Lateral Bending Sign – Spinous position – Intersegmental wedging – Usually toward concavity – Gradually increase away from sacrum • Disc herniation at level failing to laterally flex

Lumbar Ullman’s Line – Endplate line through S 1, perpendicular from sacral promontory – L 5 should be behind the line • Detection of subtle spondylolisthesis when L 5 body crosses perpendicular line

Lumbar Meyerding Rating System – Sacral base divided into quarters. Relative position of the posterior body of L 5 is made. • Grading severity of spondylolisthesis

Percentage Method/Anterolisthesis • The displacement between the posterior sacral base and the posterior aspect of L 5 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 Extremity Klein’s Line – Tangential line to outer femoral neck. Head just overlaps laterally • Slipped epiphysis suspected if head does not intersect line.

Lower Extremity Boehler’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 Extremity Skinner’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 Extremity Center 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 headacetabulum distance – Superior = 3 -6 mm – Axial = 3 -7 mm – Medial = 4 -13 mm • Various joint diseases increase the space – DJD, RA, Degenerative RA

Lower Extremity Acetabular 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: 3 mm (1 -5) – Adult: 7 mm (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: 6 mm (4. 8 -7. 2) – Female: 5 mm (3. 8 -6. 0) • Diastasis and inflammatory joint disease may widen the joint.

Lower Extremity Heel Pad Measurement – Shortest distance between the calcaneus and plantar skin surface – Male: 19 mm – 25 mm – Female: 19 mm – 23 mm • Acromegaly produces skin overgrowth exceeding the max measurement

Lower Extremity Patellar mal-alignment – Patella length-patella tendon ratio – 1: 1 • Chondromalacia patellae factor if the ratio is exceeded more than 20%

Lower Extremity Iliac 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

Lower Extremity / HIP Protrusio 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 Extremity Shenton’s line – Smooth curvilinear line along ilium and onto femoral neck and superior obturator border • Femur dislocation or fracture if line is interrupted

Lower Extremity Iliofemoral line – Smooth curvilinear line along ilium and onto femoral neck – Should be bilaterally symmetrical • Asymmetry may denote hip joint abnormality

Lower Extremity Femoral 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 Extremity Glenohumeral joint space – Average humeral headglenoid distance (superior, middle, inferior) – 4 -5 mm • Degenerative and crystal arthritis diminish the space. Posterior dislocation may widen it.

Upper Extremity Metacarpal sign – Tangential line through the fourth and fifth metacarpal heads. Third head should be proximal to this line • Turners Syndrome, post fracture deformity

Upper Extremity Acromiohumeral joint space – Acromion-humeral head – Avg. 9 mm – 7 mm-11 mm is the range • Rotator cuff tear decreases distance. • Subluxation and dislocation increase the distance

Upper Extremity Acromioclavicular joint space – Avg. acromion-clavicular distance (superior, inferior) – Male: 3. 3 mm (2. 5 -4. 1 mm) – Female: 2. 9 mm (2. 13. 7 mm) • Degenerative arthritis will decrease distance • Separation and resorption will widen distance

Upper Extremity Radio-capitellar line – Radius axis line through the elbow joint – Passes through capitellar center • Radius subluxation/dislocati on if line misses the capitellar head