Lines of alignment we need to know Flashcards
What is this line of alignment?
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Angle of the Cervical Spine
Normal:
35-45 degrees normal lordosis
Longitudinal arch of the foot
- measured
Measured:
Compare the height from the curvilinear line extending
along the horizontal arch to the base line between the
calcaneus and the base of the 1st MTP.
Normal:
150-170 degrees.
**Significance**: Pes Planus (\>170 degrees)
Pes Cavus (<150 degrees)
What is this line of alignment?
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Physiological Line of Stress (Ruth Jackson)
Normal:
Neutral: Should pass through C4/5 IVD
Flexion: Should Pass through C5/6
Extension: Should Pass through C4/5 posterior
Q Angle
- measured
- normal
- significance
- *Measured:**
- Line taking origin from ASIS through patella midpoint.
- Line through tibial plateau and midpoint of the patella.
Normal:
Men = 14 degrees
Women = 17 degrees
Significance: Altered in a variety of biomechanical issues and pathologies.
Ilio-Femoral Line
- measured
- normal
- significance
Measured:
A line along lateral margins of the ilium should continue as an unbroken curve along the superior margins of the femoral neck.
Normal:
Even appearance bilaterally
Significance:
Congenital dysplasia, SFCE, Dislocation, #
What is angle A?
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Tibial Angle (TA):
Angle between tibial shaft and tibial plateau lines.
Normal:
85-100 degrees
Ulman’s Line
- measured
- normal
Measured:
Line extended upwards at a 90 degree angle to the superior surface of the sacral base at its anterior
margin.
Normal:
It should clear the anterior inferior margin of the L5 body.
At what level is the tracheal bifurcation usually in adults?
T6
What line of alignment is this (number 3)? What method is it? What other lines of alignment are depicted in this image?
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Lumbar curve angle method 2:
Normal: 50-60
We can also see depicted (in angle 1) the sacral base angle
Normal: 41 degrees
What is the angle depicted in figure 1? What is normal?
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Q angle
Normal:
Men = 14 degrees
Women = 17 degrees
What is the angle signified by A?
- normal
What is the angle signified by B?
- normal
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A = Tibial angle
Normal:
45-61 (average 53 degrees)
B = Fibular angle
Normal:
43-62 (average 52 degrees)
Cervical line of Gravity
- measured
- normal
Measured:
The Cervical Gravity Line is created by first locating the center of the tip of the Odontoid Process, then dropping a line downward, perpendicular to the bottom of the film.
Normal:
This line should just touch the anterior body of C7
What is this line of alignment?
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Fergusons line of alignment
Normal:
Should strike anterior margin or anterior 1⁄4 of sacral base
Carpal alignment
- measured (3 lines)
- significance
1: Line curving along scaphoid, lunate, triquetrum and pisiform
2: 2nd line running along superior articulations of pisiform, lunate, scaphoid.
3: 3rd line at inferior articulation of hamate Capitate.
Significance: Altered from a variety of fractures
and pathologies.
What are these lines of alignment?
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Georges line:
ALL (anterior longitudinal line)
PLL (posterior longitudinal line)
SLL (Spino laminar line)
Lumbar Curve Angle
- 2 types:
- measured
- normal
- significance
Lumbar Curve Angle (method 1)
- *Measured**:
1: Horizontal line to superior endplate L1.
2: Horizontal line to inferior endplate L5.
Normal:
Upright: 35 – 45
Significance:
Muscular imbalance, Postural considerations, Nucleus pressure
- *Lumbar Curve Angle (method 2)**
- *Measured**:
1: Horizontal line to superior endplate L1.
2: Horizontal line to superior sacral base
Normal:
Upright: 50 - 60
Can vary from recumbent to upright positions.
Significance:
Muscular imbalance, Postural considerations. Nucleus pressure
Retropharyngeal Space
- measured
- normal
Measured:
Anterior Inferior border of C2 and posterior pharyngeal airspace.
Normal:
<5mm
What do these lines of alignment measure? Which method is indicated in each of the diagrams?
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These are methods for measuring the degree of scoliosis.
On the left = Cobb method.
On the right = Risser method.
Meyerdings’s Classifications:
- what is it used for
- measured by
To classify a spondylolisthesis
Measured:
Sacral base is divided into 4 equal parts. The
relative slip of the vertebrae above is classified.
Angle of Cx. Spine
- measured
- normal
Measured:
Midpoints of anterior and posterior tubercles of the atlas and a line through inferior endplate of C7. Perpendiculars are constructed if required.
Normal:
35-45 degrees normal lordosis
What is this line of alignment?
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The cervical line of gravity
Normal:
This line should just touch the anterior body of C7
General alignment of the wrist
- normal
- significance
1: Radioulnar articular line
2: Radial Shaft Line:
3: Radio-ulnar angle
Normal:
PA radioulnar Angles: average 83 (72-95)
Significance: Altered from a variety of fractures and pathologies.
What is this line of alignment?
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Meyerdings Classification for grading of spondylolisthesis
Symphysis Pubis Width
- measured
- normal
- significance
Measured:
Distance between opposing articular surfaces.
Normal:
Male: 6mm average
Female: 5mm average
Significance: Widening due to dysplasia, trauma, HPT, inflammatory (AS, Reiter’s). Decrease DJD.
What is this line?
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- significance
Kleins Line
Significance: if there is a failure of the femoral head to cut the line, then a slipped capital femoral epiphysis is suspected
Fergusons line
Measured:
Perpendicular line dropped from centre of L3.
Normal:
Should strike anterior margin or anterior 1⁄4 of sacral base.
Significance:
Variety of interruptions due to many pathologies. Spondylolisthesis.
Postural Compensation
McNabs Line
- measured
- normal
- significance
Measured:
Line drawn through inferior endplate at level to be evaluated. Relationships to superior articular process of vertebrae below is then assessed.
Normal:
Line should lie above tip of adjacent sup. Articular facet.
Significance: Facet Imbrication: Mechanical influence (on IVF) Postural considerations.
Increased shearing
What is the angle depicted by the number 3?
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Carrying angle
Normal:
Normally it is 5-15 degrees away from the body or 165-175 degrees towards the body
Pedicular method of rotation
- what are the 2 methods
- how is it measured
Spinous method:
Spinous process are prone to malformations and displacement and so not optimally used.
Pedicle method:
Most accepted method.
Georges (PLL, ALL and SLL) for all of spine
- measured by
- normal
- significance
Measured:
Line tracing the anterior longitudinal line, Posterior longitudinal line and spino lamina line.
Normal Measurement:
Line should be smooth, regular and uninterrupted.
Significance:
Variety of interruptions due to many pathologies. Spondylolisthesis.
What does this line help to measure?
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- what is normal?
Acetabular depth
Normal:
Females = 12mm average
Males = 13mm average
How would you describe the position of this patella? How did you measure this?
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Patella Baja
Measured the difference between patella length and patellar tendon length. A difference of more that 20% between the 2 where the tendon length is shorter than the patellar length indicates patella baja.
What is this line of alignment? What is it used for?
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Ulman’s Line
Used to check for spondylolisthesis
Normal:
Line should clear the anterior inferior margin of the L5 body.
Tracheal bifurcation level in pediatric to geriatric
- what is the level of tracheal bifurcation in:
- newborns
- 10 year old children
- adults
Newborns = T3
10 year old children = T5
Adults = T6
What is this line of alignment?
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McNabs Line
Normal: Line should lie above tip of adjacent sup. Articular facet.
Physiological line of stress (Ruth Jackson)
- measured
- normal
- significance
Measured:
Posterior aspect of Dens and Posterior Aspect of C7
Normal:
Neutral: Should pass through C4/5 IVD
Flexion: Should Pass through C5/6
Extension: Should Pass through C4/5 posterior
Significance:
Biomechanical compensation
What is this line? What is normal?
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Skinner’s Line
Normal: Relationships to the fovea is assessed and fovea should lie above or at the level of the level of the trochanteric line.
What are the black arrows pointing to? What should this space be in cm?
What are the white arrows pointing to? What should this space be in cm?
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Black arrows: retro-pharyngeal space/line
= <5mm
White arrows: retro-tracheal space/line
= <20mm
Atlanto-dental Interspace
- measured
- normal
- significance
Measured:
Anterior aspect of dens and posterior aspect of anterior tubercle.
Normal:
1-3mm adults
1-5mm children
Significance:
PARRS, Down Syndrome
What is this line of alignment?
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The atlanto-dental interspace
Normal:
1-3mm adults
1-5mm children
Knee Tibial angle
Measure:
Angle between tibial shaft and tibial plateau lines.
Normal:
85-100 degrees
Significance:
Altered in a variety of biomechanical issues and pathologies
Bohlers Angle
- measured
- normal
- signifiance
Measured:
line tangent to upper contour calcaneus tuberosity with line at posterior aspect superior surfaces of calcaneus
Normal:
28-40 degrees
Significance:
Fracture, Congenital
What is this angle?
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- normal
The femoral angle
Normal:
120-130 degrees
Patellar position
Measure:
Often taken in semi flexed position as greatest distance recorded of PT (patella tendon length)
Normal: Patella length and patella tendon usually equal (20% variance accepted)
Significance:
More than 20% = patella alta, may be seen in CMP. Less that 20% = patella baja, may indicate polio, Achondroplasia, JRA.
Skinner’s Line
- measured
- normal
- significance
Measured:
Line drawn through and parallel to axis of
femoral shaft. 2nd line at right angle to the shaft line
is constructed tangential to the tip of the greater trochanter.
Normal: Relationships to the fovea is assessed and fovea should lie above or at the level of the level of the trochanteric line.
Significance:
Conditions causing Coxa Vara #
Glenohumeral joint width space
- measured
- normal
- significance
Measure:
Superior, middle and inferior aspect of glenoid. Combined and averaged.
Normal:
4-5mm
Significance:
DJD, CPPD, arthritis, acromegaly, trauma
What is this line of alignment?
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The sacral base angle
Normal:
41 deg. (26 - 57)
Can vary by 8-12 degrees from recumbent to upright positions.
Shenton’s Line
- measured
- normal
- significance
Measured:
Curvilinear line traced along undersurface of femoral neck and continued across the joint to the inferior margin of the superior pubic ramus..
Normal:
Line should be smooth and uninterrupted. (occasionally a portion of the femoral head may slightly cross the line)
Significance:
Interrupted or discontinuous line is useful in detecting hip dislocations, fem neck #, SFCE.
Klein’s Line
- measured
- normal
- significance
Measured:
Line drawn tangential to the superior margins of the femoral neck. Bilateral examinations should be made.
Normal:
If there is a failure of the femoral head to cut the line drawn, then SFCE suspected.
Significance:
Dysplasia
SFCE
Perthes
Destructive conditions
What is this line of alignment?
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The thoracic curve angle
Normal:
Varied angles approx. 20-50degrees common
Femoral angle
- measured
- normal
- significance
Measured:
Angle formed by the axis of the neck and the long axis of the shaft of femur.
Normal:
120-130 degree’s
Significance:
< 120 Coxa Vara
> 130 Coxa Valga
Axial relationship of the elbow:
- lines
- angles
- normal
- signifiance
Lines:
Humeral Shaft line
Ulnar Shaft Line
Humeral Articular Line
(trochlea and capitulum)
Angles
Carrying angle: CA
Humeral angle: HA
Ulnar angle: UA
Normal:
Humeral avg. 85
Ulna avg. 84
Carrying avg. 169
Significance:
Altered from a variety of fractures and pathologies.
Sacro-vertebral and Lumbar Body Angles
Measured:
Lines drawn through and parallel to each lumbar bony endplate, lines being extended posteriorly until they intersect.
Normal:
L1 8 degrees
L2 10
L3 12
L4 14
L5/S1 14 (10-25)
Significance:
Muscular imbalance Postural considerations.
Facet syndromes show increase Herniations show decrease
What is this line of alignment? Which method is it?
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Lumbar curve angle method 1
Normal: 35 – 45
What is this line?
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Shenton’s Line
Fibular Angle
- normal
The angle is formed laterally between the lateral malleolus line (A line is drawn tangential to the articular surface of the lateral malleolus) and the talus line (A line drawn tangential to the articular surface of the talar dome).
Normal:
43-62 (average 52 degrees)
Sacral Base Angle
- measured
- normal
- significance
- *Measured**:
1: Horizontal line to bottom of film.
2: Line drawn parallel to sacral base.
Normal:
Upright: Avg. 41 deg. 26 - 57
Can vary by 8-12 degrees from recumbent to upright positions.
Significance:
Muscular imbalance
Postural considerations
Increased shearing
What is this line?
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In this image, does the line indicate whether this person’s hip is normal or abnormal?
Ilio-femoral line
This persons hips are normal as the line is relatively continuous and is the same bilaterally.
Carrying Angle
- measured
- normal
- significance
Measured:
Between the humeral shaft line and the ulnar shaft line.
Normal:
Carrying avg. 169
Retrotracheal space
- measured by
- normal
- indications
Measured:
Anterior Inferior border of C6 and posterior tracheal airspace.
Normal:
<20mm
Indications:
Haematoma, Trauma, Suppuration
What is the angle signified by the yellow line?
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Bohlers angle
Normal:
28-40 degrees
Hip joint distance.
- normal
- significance
Normal:
Superior: 3-6mm (average 4mm)
Axial: 3-7 (average 4mm)
Medial: 6-11mm (average 8mm)
Significance:
Medial Teardrop distance: if exceeds 11mm or > 2mm discrepancy from side to side then hip disease is most likely present. (even 1mm difference can indicate disease).
What is this line?
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Kohlers Line
Foot/ankle Tibial Angle
- normal
Angle is formed medially between medial malleolus line (A line drawn tangential to articular surface of the medial malleolus) and talus line (A line drawn tangential to the articular surface of the talar dome)
Normal:
45-61 (average 53 degrees)
Protrusio Acetabuli/ Kohlers Line
- measured
- normal
- significance
Measured:
Line tangential to cortical margin of pelvic inlet and outer border of obturator foramen. Relationships to acetabular floor is assessed.
Normal:
Acetabular floor should not cross this line and usually lies lateral to it.
Significance:
Inflammatory arthritides (RA, PS) Pagets
F Fibrous dysplasia
Thoracic curve angle
- measured
- normal
Measured:
Draw parallel lines to the superior endplate of T1 (T4) and straight line through inferior endplate of T12 (T9). Drop perpendicular lines to measure appropriate angle.
If superior and inferior vertebrae not clear T4 and T9 can be taken for apices.
Normal:
Varied angles approx. 20-50degrees common
What are the 2 systems for measuring scoliosis?
Cobb Lippman Method:
A line is drawn along superior border of cephalad (top) vertebrae. A line is drawn along inferior of caudad (bottom) vertebrae.
If endplates not visible then bottoms and tops of pedicles used.
Perpendicular lines are then drawn from each horizontal line, and the angle of their intersection measured.
Seven groups: 1: 0-20 degrees, 2: 21-30 degrees,3: 31-50 degrees,4: 51-75 degrees,5: 76- 100 degrees, 6: 101-125 degrees, 7: 126 and above,
Cobb method gives larger measurements then Risser technique by average of 25% or about 10 degrees.
Risser-Ferguson Method:
The centres of the end (top and bottom) and apical vertebral bodies are identified. These points are then connected and the angle of intersection measured.
Acetabular Depth
- measured
- normal
- significance
Measured:
A line drawn from the superior margin of the pubis at the symphysis joint to upper outer acetabular margin. The greatest distance from this line to the acetabular floor is measured.
Normal:
Male: 7 - 18mm (average 13mm)
Female: 9 - 18mm (average 12mm)
Significance:
< 9mm considered shallow and dysplastic.
How would you describe the position of this patella? How did you measure this?
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Patella Alta
Measured the difference between patella length and patellar tendon length. A difference of more that 20% between the 2 where the tendon length is longer than the patellar length indicates patella alta