3. Adult Idiopathic Scoliosis
• Pre-existing adolescent idiopathic scoliosis
• Slow increase in curvature
• Curves increase 0.5-2o per year
• Adolescent curves <30o unlikely to
progress significantly into adulthood
• Curves >50o likely to worsen
• Requires monitoring
4. ASA 1
• smaller flexible curves
• 18-30 years old
• Posture and cosmetic concerns
• Pain can be an issue in
unbalanced curves
• reducibility in abnormal posture
and Cobb angle
5. ASA 2
• larger more rigid curves
• adults 30-40 years old
• Pain and posture equally
issues
• Pain an issue even in balanced
curves
• early degenerative changes
• Intervention could stop
progression to ASA 3
6. ASA 3
• large, rigid curves
• older adults 40+
• Pain is the primary concern
• Moderate to severe
degenerative changes
• Most commonly lumbar curves
• No previous history of scoliosis
could indicate degenerative de
novo scoliosis
7. Adult Degenerative (de novo) Scoliosis
• Large, rigid curves
• >50 years old
• Due to degenerative instability
• Loss of lumbar lordosis
• Settling of discs lead to positive
sagittal balance
• Pain is primary concern
8. Prevalence of Adult Scoliosis in Back Pain
Perennou et al
• 671 LBP patients:
• 7.5% with scoliosis
• Prevalence increased with
age:
• 2% before 45 years (ASA)
• 15% after 60 years (DDS)
Robin et al
• 554 LBP patients
• Aged 50 to 84
• 30% scoliosis >10°
• At 5 year follow up
• 40% scoliosis >10°
• Additional 10%
9. Progression of Adult Curves
Spinal
Degeneration
Soft tissue
integrity lost
Functional
unit instability
increased
Scoliosis
Progression
Boney
adaptation
11. Presentation
• AIS – rarely have pain
• Low back pain & stiffness most
common – 85%
• Radicular pain
• Neurogenic claudication
• May lean forward
– open narrowed spinal canal
– secondary to loss of lumbar
lordosis
• Compensatory maneuvers for upright
posture
– Bend at hips & knees
• Strain on muscles causing early fatigue
& pain
• Dubousset - Cone of Balance
15. Differences in Treatment in AIS and
Fixed Adult Scoliosis
• Curves are generally stiff
• Higher risk with a higher complications rate in
adults (high as 80%)
• More invasive surgical procedure is needed
(VCR, osteotomies, Anterior release, etc.)
• Goals
• Correction of 3D deformity
• Restoration of balance
• Fusing minimal number of levels necessary
• Stop curvature progression
• Allowing residual spinal mobility
17. Pelvic Incidence
• Morphological parameter
• Anatomical char of pelvis
• Defines lumbar alignment
• No variation over time in
adults
• Mimics vector of load
transmitted to sacral
plateau
• Avg PI = 55o +/- 10o
Pelvic Incidence
Morphological parameter
Not Affected by patient position
No Variation over time in adult population
18. Pelvic Tilt
• Positional parameter
• Spatial orientation of pelvis
• Compensatory mechanisms
• Normal ~13o +/- 6o
• goal <20o
• As PT inc the center of
gravity moves more
posterior to femoral heads
19. Sacral Slope
• Determines position of
lumbar spine
• Maximal retroversion at 00Pelvic Tilt (PT)
Positional parameter
Compensatory Mechanisms
Affected by patient position
Normal ~ 13 degrees
Alignment tip #1
Want PT<20 degrees
Pelvic Incidence
Morphological parameter
Not Affected by patient position
No Variation over time in adult population
23. Sacral Morphology & Lordosis
• Low PI
– Low sacral slope
– Low pelvic tilt
– Vertical sacrum
– Flat lumbar lordosis
– Low shear stress at LS jxn
– Low risk of
spondylolisthesis
Sacral morpholog
W
A
24. Sacral Morphology & Lordosis
• Larger PI
– High SS
– High PT
– Increased lumbar lordosis
– High risk of spondylolisthesis
– High shear stress at JS jxn
– Horizontal sacrum
– High possibility of
retroversion
Goal: LL = PI (+/- 9o)
Sacral morpholog
W
A
25. Compensatory Pelvic Tilt
Hip Retroversion can allow C7PL to be in balanceSame structural deformity … different compensation
Large SVA, No PT Moderate SVA / PT No SVA, Lar
Same structural deformity … different compensation
Large SVA, No PT Moderate SVA / PT No SVA, Large PT
me structural deformity … different compensation
ge SVA, No PT Moderate SVA / PT No SVA, Large PT
Large SVA,
No PT
Mod SVA,
Mod PT
No SVA,
Large PT
26. Pelvic & Knee Compensation
• Retroversion (inc PT) can
compensate for kyphosis
• Severe kyphosis causes hip
extension – limiting PT
• Compensate with knee flexion
27. • 298 patients
• correlate radiographic
measures with patient-
based quality of life
Positive sagittal balance
• Greater pain
• Lower physical function
• Poor self image
• Poor social function
“Correlation of Radiographic Parameters and Clinical
Symptoms in Adult Scoliosis”
- Glassman, et al. Spine 2003
28. • Coronal shift > 4 cm
• Poorer function
• Greater pain
• + SB predicts clinical
symptoms
• Thoracolumbar and lumbar
curves have worse outcomes
than thoracic curves.
• Significant coronal imbalance
was associated with pain and
dysfunction.
“Correlation of Radiographic Parameters and Clinical
Symptoms in Adult Scoliosis”
- Glassman, et al. Spine 2003
30. Alignment Objectives
• Quality of life driven goals:
• SVA <5cm
• T1 Tilt <0o
• PT <25o
• Proportional SB: LL = PI +/- 9o
31. Case: BM
• 56y/o M p/w more than 2 year of low
back pain rad to LEs. 2012 L2
hemilaminectomy for LBP to LE. Failed
trial of spinal cord stimulator 1/2013.
Early fatiguing and leaning forward
• PMH: HTN, HLD, IBS, OSA
• Meds: Dilaudid, Valium, Lexapro
• Neuro: Intact; strength 5/5 throughout
ASA1 are usually smaller more flexible curves in younger adults 18-30 years old. Posture and Cosmetic issues tend to be the main problem. Pain can be an issue particularly in unbalanced curves i.e. RT1. There is a potential reducibility in both the abnormal posture and cobb magnitude.
The picture shows a relatively well balanced thoraco-lumbar curve. Pain and Aesthetics were both considerations for this 21 year old female.
ASA 2 are usually larger more rigid curves in middle aged adults 30 to 40 years of age. Pain and posture equally issues. Pain can be an issue even in balanced curves, usually because the spine is less flexible and an early degenerative process is starting. Intervention in ASA 2 could potentially to stop progression to ASA 3 - (This idea of early intervention at “middle age” is also suggest by Schwab Spine 2002)
ASA 3 are usually larger, very rigid curves in older adults 40+. Pain is the primary issue. Moderate to severe degenerative changes are present.
ASA 3 are commonly present as lumbar curves. Or other curves with lumbar pain. The only way to distinguish ASA 3 lumbar curves and DDS Lumbar curve is via history of scoliosis. If there is no previous history of scoliosis this could indicate a Degenerative De Novo Scoliosis DDS.
In studies by Perennou and Robin et al the prevalence of degenerative adult scoliosis, ASA and DDS in patients with back pain has been studied.
Perennou found that out of 671 LBP sufferers, 7.5% had evidence of scoliosis on x-ray. The prevalence of scoliosis increased with age; 2% before 45 years (most likely ASA) up to 15% after 60 years (probably DDS).
Robin et al. found that out of 554 LBP patients aged 50 to 84, 30% had a spinal curvature greater than 10 degrees. At 5 year follow up an additional 10% had this magnitude of scoliosis
These studies suggest that a significant number of older people have an adult scoliosis and its prevalence and progression is directly related to advancing age and that is strongly associated with lower back pain in this population.
As adults do not grow, one of the main progressive factors in Adolescents is not present in Adult cases. In progressive adult curves a different theory of progression is suggested.
Either due to pre-existing biomechanical issues such as pre-existing scoliosis or due to segmental injuries the functional unit of the spine begins to degenerate.
As a result of this degeneration soft tissue integrity is lost (due to Davis’s law).
This loss of soft tissue integrity leads to functional unit instability.
This instability allows further scoliotic progression.
Over a period of time the bone tries to adapt and further degeneration occurs ( due to Wolff’s law)
This is another vicious cycle of progression, however it revolves around degenerative instability as apposed to growth modulation.
Patients with positive sagittal balance measured from C7 to the posterior margin of the sacrum had the most significant compromise in health status when compared to patients who were in neutral balance or negative global sagittal balance. Patients with positive sagittal balance reported greater pain, diminished physical function poorer self image and social function
The most significant findings for patients with no prior surgery were noted in the assessment of coronal and sagittal balance.
Patients with coronal shift greater than 4 cm reported poorer function based on the SRS-22 and greater pain on the SF-12 and ODI compared to patients with a coronal shift less than 4 cm.