| A | B |
|---|
| Basilar Angle (martin's basilar angle) | line is drawn from the nasion to the center of the sella turcica. aline is drawn from the basion (ant. foramen magnum) to the center of the sella turcica. |
| Basilar angle positive | if angle is >152 degrees it is indicative of platybasia which may be associated with basilar impression |
| McGregor's line | the hard palate to the base of the occiput |
| McGregor's line Positive | if the odontoid is >8mm above this line in males or >10mm above this line in females, this indicates basilar impression, it is the most accurate evaluation for basilar impression |
| Chamberlain's line | line from hard palate to the opisthion (posterior foramen magnum) |
| Chamberlain's line positive | if the odontoid is >7mm above this line, this indicates basilar impression |
| Macrae's line (foramen Magnum line) | line drawn from ant. foramen magnum to post. foramen magnum |
| Macrae's line positive | if the occipital bone is above the line, indicates basilar impression |
| Atlantodental Interspace (ADI) | line drawn from C1 ant. tubercle to odontoid |
| ADI positive | if this space is >3mm in adults or >5mm in children this indicates transverse ligament rupture or instability due to trauma, down's syndrome or inflammatory arthritis |
| George's Line | line form posterior body margins are checked for alignment with what should be smooth continuous line |
| George's line positive | discontinuous line may indicate A-P vertebral malposition such as anterolisthesis or retrolisthesis |
| Posterior Cervical line | lines drawn at each spinolaminar junction should form a smooth arc-like curve |
| Posterior cervical line positive | discontinuous line may indicate a A-P vertebral malposition such as anterolisthesis or retrolisthesis |
| Stress lines of cervical spine (Jackson's) | lines drawn at C2 and C7 posterior bodies, |
| Stress lines of cervical spine (jackson's) POSITIVE | flexion should intersect at C5-C6. extension should intersect at C4-C5. may be altered by muscle spasm, joint fixation , or disc degeneration |
| Prevertebral soft tissues | lines drawn from anterior vertebral bodies to posterior margin of air shadow of the Pharynx (C2), larynx (C4), and trachea (C7) |
| Prevertebral soft tissue POSITIVE | retropharyngeal >7mm, retrolaryngeal >14mm, Retrotracheal >22mm, this is indicative of a soft tissue mass (tumor, infection, hematoma) |
| Cobb's method of scoliosis and evaluation | less then 20 degrees-monitor, 20-40 degree angle- brace, > 40 degrees- surgery, BEST METHOD FOR SCOLIOSIS MEASUREMENT |
| Risser-Ferguson method of scoliosis evaluation | locate superior and inferiro extremes of scoliosis and apical segment, diagonal lines drawn to locate center of the vertebral bodies. two lines drawn connecting center of apical segment with each end vertebra and resultant angle measured. Values are 25% below Cobb method of evaluation, for scoliosis evaluation |
| LumboSacral Inclination (sacral bas angle, ferguson's angle) | oblique line drawn through and parallel to sacral base, horizontal line parallel to bottom edge of film |
| LumboSacral Inclination Positive | normal angle is 26-57 degrees, average angle is 41 degrees |
| Meyerding's grading method of spondylolisthesis | sacral base is divided into quarters and the relative position of the post. inferior aspect of L5 is made |
| Meyerding's grading positive | determines degree of anterolisthesis, if vertebral body completely slipped anterior=spondyloptosis |
| Ullmann's line | line drawn parallel and through sacral base, perpendicular line drawn from the sacral promontory |
| Ullmann's line Positive | L5 beyond the perpendicular line = spondylolisthesis |
| Eisenstein's Method for Sagittal Canal Measurement | line drawn to connect tips of superior and inferior articular processes. distance to posterior body margin at the midpoint is measured |
| Eisentein's method positive | measurement <15mm= spinal canal stenosis |
| Canla to Body ratio | 1.interpediculate distance, 2. sagittal canal dimension, 3. transverse body dimension, 4. sagittal body dimension, significance- 1x2/3x4 = the higher the ratio, the smaller the canal if >1:6 at L3,L4 or 1:6.5 at L5 this denotes canal stenosis |
| Lumbosacral disc angle | lines drawn parallel and through the inferior end plate of L5 and the superior end plate of S1, normal is 10-15 degrees |
| Lumbar Gravity Line (ferguson's line) | vertical line drawn through the center of L3 vertebral body |
| Lumbar Gravity Line Positive | line should intersect sacral base, if the line is anterior to the sacrum, it may indicate hyperlordosis, if the line is posterior to the sacrum, it may indicate hypolordosis |
| Macnab's Line | line drawn parallel and through the inferior end plate |
| Macnab's line positive | if the line intersects the superior articular process of the vertebra below, extension malposition or facet imbrication is suspected |
| Hadley's S Curve | curvilinear line drawn along the inferior aspect of the TP, the inferior articular process and through the joint space to the superior articular process of the vertebra below |
| Hadley's S Curve Positive | should be a smooth shaped S curve, an interuption in the S curve indicates subluxation or facet imbrication |
| Kohler's Line (measurements of protrusio acetabuli) | line drawn along the pelvic inlet to the outer aspect of the obturator foramen |
| Kohler's line Positive | if the acetabular floor crosses the line, this indicates protrusio acetabuli |
| Shenton's Line | a smooth curvilinear line is drawn along the inferior femoral neck to the superior aspect of the obturator foramen |
| Shenton's line Positive | an interupted, discontinuous line indicates a dislocation, neck fracture, or slipped capital epiphysis |
| Iliofemoral Line | a smooth curvilinear line is drawn along the outer ilium, across the joint and onto the femoral neck |
| Iliofemoral Line Positive | bilateral asymmetry indicates a slipped femoral capital epiphysis, dislocation, fracture, or dysplasia |
| Femoral Angle (Mickulics's angle) | two lines are drawn through and parallel to mid-axis of the femoral shaft and femoral neck |
| Femoral Angle Positive | normal angle is 120-130 degrees, <120degrees coxa vera is indicated, if angle is >130 degrees coxa valga is indicated |
| Skinner's line | a line is drawn through and parallel to the femoral shaft. a perpendicular line is drawn tangential to the tip of the greater trochanter |
| Skinner's line positive | the fovea capitus should lie above or at the level of the trochanger line, if the fovea capitus fall below this line, it indicates fracture or coxa vera |
| Klein's Line | line is drawn along the outer margin of the femoral neck |
| Klein's line Positive | femoral head should intersect the line. Failure to intersect the line indicates a slipped femoral capital epiphysis |
| Patellar position | a line is drawn between the superior and inferior patellar pole. a line is drawn between the inf. patellar pole and tibial tubercle. |
| Patellar position Positive | Patellar length and patella tendon length should be approximately equal. if the tendon length is 20% greater ten the patellar length, this indicates patella alta. |
| Heel Pad measurement | the shortest distance is measured between the plantar surface of the calcaneous and the external skin contour |
| Heel Pad measurement Positive | if this distance is >25mm in a male or >23mm in a female, this indicates increased thickness often associated with acromegaly |
| Boehler's angle | the three highest points on the superior aspect of the calcaneous are connected with two lines |
| Boehler's angle positive | if the resultant angle is <28 degrees, this is indicative of a calcaneal fracture or dysplastic calaneus |
