Scoliosis Flashcards
What is Scoliosis?
A complicated deformity, characterised by both lateral curvature and vertebral rotation.
As the disease progresses:
- the vertebrae and spinous processes of the major curve rotate toward the concavity of the curve
- ribs follow the rotation of the vertebrae
Concave side of the curve:
- ribs close together
- the anterior ribs pushed anteriorly.
Convex side:
- ribs widely separated
- the posterior ribs pushed posteriorly, causing the characteristic rib hump seen in thoracic scoliosis.
A significant lateral deviation (more than 10° ) of the spine with vertebral rotation within the curve
Remember: True scoliosis is not only a deformity in the coronal plane, but it is also a rotational deformity.
Scoliosis curves most common in thoracic spine
Diagnosed in childhood or early adolescence with the primary age of onset being 10-15 years old
A Cobb angle of <10°:
- asymptomatic
- does not progress
Treatment:
- smaller curves do not require treatment
- larger curves require a brace or surgery to restore normal posture
What is Dextroscoliosis?
Curve convex to right
What is Levoscoliosis?
Curve convex to left
What is Kyphoscoliosis?
Scoliosiswith component of kyphosis
What is S-Curve Scoliosis?
3 adjacent curves (1 to right, 1 to left and 1 at lumbosacral junction)
What is Primary curve (Aka major curve or structural curve) ?
The most pronounced curve where the main structural abnormality is present
What is Secondary curve (Aka minor curve or non-structural curve)?
Less pronounced compensatory curves that develop above and/or below the primary curve to maintain balance
What is the Apex?
The vertebral body or disc space demonstrating the greatest rotation and/or furthest deviation from the expected centre of the vertebral column. The endplates of the apical vertebra are often horizontal or near horizontal.
What is the end vertebrae?
The vertebrae most tilted towards each other and present on either side of the apex. They form the basis of the Cobb angle.
What is neutral vertebrae?
Present on either side of the apex with no rotation (axial plane). In some cases, they are like end vertebrae but never closer to the apex than the end vertebrae.
What is stable vertebra?
The first vertebra below the lowest curve, roughly bisected by the central sacral vertical line
What type of curve is a primary curve?
first to develop
At the time of diagnosis, it is not always possible to differentiate primary curves from secondary curves.
structural
largest curve
not correctable with ipsilateral bending
vertebral morphologic changes (E.G wedging)
May progress
Usually > 25 degrees
What type of curve is a secondary curve?
develop to balance the head and trunk over the pelvis, in the frontal and the sagittal plane.
At the time of diagnosis, it is not always possible to differentiate primary curves from secondary curves.
compensatory curve
smaller curve
non structural
correctable with ipsilateral bending
doesn’t usually progress
usually <25 degrees
What type of curve is a structural curve?
Do Not correct with side-be
What type of curve is a non-structural curve?
can be secondary curves - postural, secondary to short leg or muscle spasm.
What is cobb angle?
measured between the superior endplate of the proximal end vertebra and the inferior endplate of the distal end vertebra
most consistent despite inter-examiner variability
Two lines are drawn on a PA spinal radiograph
one extending from the top of the most tilted upper vertebra and the other from the bottom of the most tilted lower vertebra.
The angle formed by these lines is the Cobb angle.
What is risser-ferguson method?
First line originating at the centre of the upper end-vertebra
Second line from the centre of the lower end-vertebra
Angle formed by the intersection of two lines at the centre of the apical vertebra gives the DEGREE OF CURVATURE
tell me about cobbs vs risser-ferguson
Risser’s method - only used on congenital curves
Cobb’s method - preferred method
Cobb’s is more consistent inter- and intra-examiner reliability of measurement.
Cobb’s gives higher measurement (5-10° or 25%)
Regardless of which method is used it is essential that the same vertebral levels are used on subsequent examinations for follow-up
Radiograph must be produced with patient in same position as initial study
(So need standardized positioning protocol)
What is pedicle rotation?
After measuring the angle of curvature, estimate the degree of rotation of the vertebra at the apex of the curve by looking at the relation of the pedicles to midline.
GRADE 0: No pedicle rotation.
GRADE 1: Pedicle visible between the lat. edge of the VB & midline.
GRADE 2: Pedicle of the convexity visible just lateral to the center line.
GRADE 3: Pedicle of the convexity overlaps the center line.
GRADE 4: Pedicle is rotated past center line.
What is the Skeletal Maturity: Iliac Apophysis (Risser’s sign)?
Determine the physiological or skeletal maturity of the patient to treat patients effectively as Skeletal maturity and chronological age do not necessarily match.
The iliac crests provide a convenient index of skeletal maturity.
Appears 16 M, 14 F
Grows progressively toward PSS - Lat-med
Grades 1-4 within 1yr (capping)
Grade 5 or fusion takes 2-3yrs after capping
When the iliac crest apophyses meet the sacroiliac junction and firmly seal to the ilium, maturation is nearly complete.
once skeletal maturity has been reached, curvature below 30 degrees do not progress
What is the skeletal maturity - Left Hand & Wrist – Greulisch &Pyle ?
A single AP view of the left hand and wrist to estimate skeletal maturity
Patients under 20 yoa
Important in planning treatment regime
What is the vertebral maturity: Vertebral Ring Apophysis?
Look for evidence of maturation in the VBs at the endplates.
When the plates blend in with the VB to form a solid union, maturation is complete.
What are the different types of scoliosis?
Structural (Non-functional):
- Idiopathic
- Congenital
- Degenerative
- Neuromuscular
- Post-traumatic
2. Non-structural (Functional)
- postural scoliosis
- compensatory scoliosis
- due to muscle spasm (secondary to lumbar or thoracic injuries) or leg length discrepancy(causing a lateral shift in the spine)
3. Transient structural scoliosis
- sciatic scoliosis
- hysterical scoliosis
- inflammatory scoliosis
tell me about Structural Scoliosis : Idiopathic Scoliosis
Unknown cause
most common type of scoliosis
usually diagnosed during puberty
Equal prevalence in boys and girls though curves greater than 30° that require treatment is more prevalent in girls than boys (ratio 1:8)
Does not require surgical intervention
Further divided into:
infantile idiopathic scoliosis – 0 – 3 years of age
juvenile idiopathic scoliosis – 4 – 10 years of age
Adolescent idiopathic scoliosis – >10 years of age
Tell me more about infantile idiopathic scoliosis?
Presents as a left thoracic curve in 90% of cases
The male/female ratio is 3:2
Tell me more about juvenile idiopathic scoliosis?
The male/female ratio is 1:2 to 1:4
Boys are more affected between 3 and 6 years of age (1:1)
Girls are more affected between 6 and 10 years of age (1:8)
The number of right and left curves is equal in the younger group (<6 years at presentation)
Right curves predominate in the older group (80%).