scoliosis seminar

Scoliosis

Presenter: Dr. Kaushik Kr. DuttaPGT, Dept. of Orthopaedics

Moderator: Dr.A Dutta Associate Prof., Dept. of Orthopaedics

SMCH, Silchar

Introduction• “scoliosis” - Greek word meaning “crooked.”• Scoliosis is defined as a lateral deviation of the normal vertical line

of the spine. • Associated with rotation of the vertebrae. • Three-dimensional deformity of the spine - sagittal, frontal, and

coronal planes

• Non-structural of Postural• Structural

Classification

Classification

• Based on aetiology1.Idiopathic2.Congenital3.Neuromuscular4.Syndromic or generalised disease

Idiopathic

• Infantile• Juvenile• Adolescent

• The end vertebrae (E) are those most tilted,

• the apex (A) is vertebra deviated farthest from the center of the vertebral column.

• A neutral vertebra (N) is one that is not rotated,

• a stable vertebra (S) is one that is bisected or nearly bisected by the CSVL (dotted line), which is exactly perpendicular to a tangent drawn across the iliac crests (solid line).

• spinous processes deviate more and more to the concave side

• rib hump in convex side

Postural Scoliosis

•  Characteristics of Nonstructural (functional) scoliosis:• A reversible lateral curve of the spine that tends to be

positional or dynamic in nature.

• No structural or rotational changes in the alignment of the vertebrae.

• Disappears when the patient is supine or prone or sitting

• Correction of the lateral curve is possible by:• Forward or side bending. This test is done to determine whether

the curve straightens out as the child bends forward and to identify a visible, rotational deformity of the rib cage

• Positional changes and alignment of the pelvis or spine.• Muscle contraction• By correction of a leg-length discrepancy

• Etiology of Nonstructural scoliosis

Leg length discrepancy: (structural or functional) Measurable difference because of a dislocated hip, asymmetric leg or foot postures.

Habitual asymmetric posture: Sitting with weight shifted onto one hip or standing with weight primarily supported on one leg results in asymmetric flexibility and tightness in soft tissue of the trunk and hips.

Muscle guarding or spasm from a painful stimuli in the back or neck,

Potential Muscle Impairments Mobility impairment in structures on the concave side of the

curves. Impaired muscle performance due to stretch and weakness

in the musculature on the convex side of the curves. If one hip is adducted, the adductor muscles on that side

have decreased flexibility and the abductor muscles are stretched and weak. The opposite occurs on the contralateral extremity.

With advanced structural scoliosis, cardiopulmonary impairment may restrict function.

• Potential Sources of Symptoms Muscle fatigue and ligamentous strain on the side of the

convexity Nerve root irritation on the side on the concavity

Structural scoliosis

INFANTILE IDIOPATHIC SCOLIOSIS

• Younger than age 3 years• Boys > girls, • Primarily thoracic and convex to

the left. • Asso with Mental deficiency, CDH,

plagiocephaly, congenital heart defects

• Self-limiting and spontaneously resolve (70% to 90%)

INFANTILE IDIOPATHIC SCOLIOSIS

• Curve Progression • Resolving –

• Age < 1 year, smaller curves, • No compensatory curves • Asso with plagiocephaly or other

moulding abnormalities• Progressive -

• Compensatory or secondary curves develop,

• > 37 degrees by Cobb Method

INFANTILE IDIOPATHIC SCOLIOSIS

• Mehta – 1. Rib Vertebral Angle Difference

(<20° - resolving)

2. Two phase radiographic appearance

Phase 1: rib head on convex side does not overlap vertebral body. Phase 2: rib head on convex side overlaps vertebral body.

JUVENILE IDIOPATHIC SCOLIOSIS

• Between the ages of 4 and 10 years

• Right Thoracic curves• 12% - 21% of idiopathic• Female-to-male ratio is 1 : 1

btwn 3 to 6 yrs of age,4 : 1 from 6 to 10 yrs of

age, 8 : 1 at 10 years of age.

ADOLESCENT IDIOPATHIC SCOLIOSIS

• Child > 10 years of age but before skeletal maturity

• Proposed etiological factors, (1)genetic factors, (2)neurological disorders, (3) hormonal and metabolic dysfunction, (4) skeletal growth, (5) biomechanical factors, and (6) environmental and lifestyle factors.

ADOLESCENT IDIOPATHIC SCOLIOSIS –

Natural History1. Prevalence2. Progression of curve3. Problems in adult life

Progression of curve

Problems in adult life

(1)back pain, (2)pulmonary function, (3)psychosocial effects, (4)mortality, and (5)curve progression.

PATIENT EVALUATION

• History, • Complete physical and

neurological examinations, and • Radiographs of the spine

History

• Backache • Menarchal status• Parental height• Family history

Physical examination

• Serial measurement of height• Inspection of the spine - hair

patches, or hemangiomas or café au lait spots

• Asymmetry of the shoulder, scapula, ribs, and waistline

• Spinal balance, hypokyphotic in sagittal plane

• Adams forward bending test• Limb lengths

Adams forward bending test

Adams forward bending test

Scoliometer

• < 7 degrees is normal

RADIOGRAPHIC EVALUATION

• Posteroanterior and lateral radiographs• Right and left bending films, traction films,

fulcrum bending films, or push prone radiographs – flexibility

• Stagnara - eliminate rotational component of the curve.

• Radiographic parameters - to assess maturity.Hand and wrist and development of the iliac apophysis (Risser sign), triradiate cartilage, olecra- non apophysis ossification, and digital ossification• Peak height velocity (PHV) - better

Stagnara derotation views



MEASUREMENT OF CURVES

• Cobb method

VERTEBRAL ROTATION

• Nash and Moe• Perdriolle and Vidal

Nash and Moe

Perdriolle torsion meter For measuring vertebral rotation

SAGITTAL BALANCE

• Plumb line or sagittal vertibral axis

Assessment of VertebralAlignment and Balance

• The plumb: line is a vertical line drawn downward from the center of the C7 vertebral body, parallel to the lateral edges of the radiograph

• CSVL :is a roughly vertical line that is drawn perpendicular to an imaginary tangential line drawn across the top of the iliac crests on radiographs. It bisects the sacrum.

• CORONAL BALANCE is evaluated by measuring the distance between the CSVL and the plumb line

• greater than 2 cm is abnormal

• SAGITTAL BALANCE is evaluated by measuring the distance between the posterosuperior aspect of the S1 vertebral body and the plumb line

Sagittal vertical axis (SVA)

CURVE PATTERNS

• PONSETI AND FRIEDMAN CLASSIFICATION

1. Single major lumbar curve2. Single major thoracolumbar curve3. Combined thoracic and lumbar

curves (double major curves)4. Single major thoracic curve5. Single major high thoracic curve6. Double major thoracic curve*

KING CLASSIFICATIONType Characteristics

Type I Lumbar curve is larger than the thoracic curve or nearly equal, but the lumbar curve is less flexible on side bending

Type II

A combined thoracic and lumbar curve and thoracic curve is larger than or equal to the lumbar. On supine side-bending radiographs, the lumbar curve is more flexible than the thoracic curve

Type III

Thoracic scoliosis with the lumbar curve not crossing the midline

Type IV

Single long thoracic curve, with L4 tilted into the curve and L5 balanced over the pelvis

Type V

A double structural thoracic curve. The first thoracic vertebra is tilted into the concavity of the upper curve, which is structural. An elevation of the left shoulder is a frequent finding. There is an upper left thoracic rib hump and a lower right thoracic rib prominence

LENKE CLASSIFICATION

(1)Identification of the primary curve,

(2)Assignment of the lumbar modifier, and

(3)Assignment of the thoracic sagittal modifier

LENKE CLASSIFICATION

LENKE CLASSIFICATION

Classification of neuromuscular disorders causes

of scoliosis

Cerebral palsy

A and B, Group I double curves with thoracic and lumbar component and little pelvic obliquity. C and D, Group II large lumbar or thoracolumbar curves with marked pelvic obliquity

Congenital scoliosis

• Classification 1. Failure of formation

1. Partial failure of formation (wedge vertebra)2. Complete failure of formation (hemivertebra)

2. Failure of segmentation1. Unilateral failure of segmentation (unilateral

unsegmented bar; 2. Bilateral failure of segmentation (block

vertebra;

3. Miscellaneous

Congenital scoliosis

Defects of formation. A, Anterior central defect. B, Incarcerated hemivertebra. C, Free hemivertebra. D, Wedge vertebra. E, Multiple hemivertebrae.

Congenital scoliosis

Block vertebra. Unilateral and unsegmented bar with contralat- eral hemivertebra

Treatment of infantile idiopathic scoliosis

• 70-90% natural favourable histroy- no active treatment required

• initial curve <250, RVAD<200 –observation with radiographic followup every 6 months

• Most resolving curves corect by 3 yrs age• Follow up even after resolution till adolescent

Treatment options for progressive curves

• Serial casting + bracing+ later fusion• Preoperative traction + later fusion• Growing rod or vertical expandable prosthetic

titanium rib( VEPTR) instrumentation without fusion

Casting and bracing

• Best results if casting started < 20 months of age and <600 curves

• Cast change every 2-4 months• Once corrected to < 100 use custom moulded

brace

Operative treatment

• Indicated if curve is severe or increases despite use of an orthosis/casting

• Principle of surgery- surgery should not only stop progression of the curve but also allow continued growth of the thorax and development of the pulmonary tree

• Fusionless instrumentation techniques are preferred(VEPTR)

• If surgical fusion is necessary- short ant and post artrodesis including only the primary curve

• Combined fusion necessary- to prevent crankshaft phenomenon

Treatment of juvenile idiopathic scoliosis

• Curves <200 – observation+ examination and standing PA radiograph every 4-6 months

• Evidence of progression on radiograph- change in curve 5-70- brace treatment

• Curve not progressing- observation till skeletal maturity

SURGEON VS ORTHOTISRestlessness with Over-enthusiastic Tubular vision syndrome ! Proponent of Brace

Breathless expectancy on Braces

Inborn Nihilism in Conservatism ?

Balance

EVIDENCE BASED MEDICINE

UNREALISTIC UNREALISTIC

PRAGMATISM

Principle: Three point fixation

To prevent curve progression during high risk period of skeletal growth.

MILWAUKEE BRACE

Brace teatment (TLSO)

Boston brace Charleston bending brace

Evaluation of Brace Treatment of Juvenile Idiopathic Scoliosis by the Rib-Vertebral

Angle Difference (RVAD)

• If the RVAD values progress above 10 degrees during brace wear, progression can be expected.

• If the RVAD values decline as treatment continues, part-time brace wear should be adequate.

• Those patients with curves with RVAD values near or below 0 degrees at the time of diagnosis generally will require only a short period of full-time brace wear before part-time brace wear is begun.

Operative treatment

Important consideration- • Expected loss of spinal height,

Limited chest wall growth and lung development

• Crankshaft phenomenon

FIGURE Crankshaft phenomenon.

A, Spine with scoliosis. B, Despite solid posterior fusion, continued anterior growth causes increase in deformity.

Surgical options Child <8yrs and small- growing rod instrumentation- • principle of surgery – posterior instrumentation

that is sequencially lengthened to allow longitudinal growth while still attempting to control progressive spinal deformity.

• surgery is required every 6 months to lengthen the construct

• A TLSO is used for first 6 months• Dual growing rod- effective in controlling

severe spinal deformities and allowing spinal growth, apical fusion doesn’t become necessary in course of Rx

Guided growth and physeal stapling

Principle of surgery- interertebral stapling is used to produce a tethering effect on the convex side of the spine. This tether theoritically will allow for continued growth on the concave side of the spine deformity and gradual correction of the deformity with growth Indications –1. Age <13 yrs in boys and 15 yrs in girls2. Skeletal maturity of Risser grade 0 or 1, with

1yr of growth remaining by wrist bone age3. Minimal rotation of both thoracic and lumbar

curves of 450 and flexibility to < 200 and a sagittal thoracic curve of 400 or less

• Child age >9/10yrs or unable to coperate with demand of growth rod-

Instrumentation and spinal fusion

Treatment of adolescent idiopathic scoliosis

• Nonoperative treatment1. observation- young patient with mild curve

<200

2. orthotic treatment- progression of curve beyond 250

Curve of 30-400 in skeletally immature SRS optimal inclusion criteria for bracing:• Age 10yrs or older• Risser grade 0-2• Primary curve angle 25-400

• No prior treatment• If female either premenarchal or less than 1 yr

post menarchal 3.Underarm cast- seldom is used now a days

Indications for operative treatment for adolescent

idiopathic scoliosis• Increasing curve in growing child • Severe deformity (>50 degrees)

with asymmetry of trunk in adolescent

• Pain uncontrolled by nonoperative treatment

• Thoracic lordosis • Significant cosmetic deformity

Surgical options

• Posterior surgeries1. Facet fusion- Moe/Hall technique2. Posterior spinal instrumentation- multiple hook segmental

instrumentation pedicle hook implantation transverse process hook implantation lamina hook implantation sublaminar wires sublaminar cables

Pedicle fixation- lumbar pedicle screw

thoracic pedicle screwFor rigid curves- Halo-gravity traction temporary distraction rod Anterior release of thoracic and lumbar

spine Osteotomy in complex spinal deformity Posterior thoracic vertebral column

resectionFor posterior rib prominence(cosmetic purpose)Posterior thoracoplastyConcave rib osteotomies

• Anterior surgeries Disc excision Anterior instrumentation of a

thoracolumbar curve with CD horizon legacy dual rod instrumentation

Anterior thoracoplasty• Other surgeries- Video assisted thoracoscopy- anterior release discectomy CD horizon eclipse spinal insrumentation

FIGURE41-32 A, Skin incisions for posterior fusion and autogenous bone graft. B, Incisions over spinous processes and interspinous ligaments. C, Weitlaner retractors used to maintain tension and exposure of spine during dissection.

FIGURE

41-33 A and B, Cobb curets used to clean facets of ligament attachments.

Moe technique of thoracic facet fusion.

FIGURE41-35 A and B, Moe technique of

lumbar facet fusion.

FIGURE41-36 A-C, Hall technique of facet

fusion

Posterior spinal instrumentation

• Goal is to correct the deformity as much as possible and to stabilized the spine in the corrected position while the fusion mass become solid

• In 1962 Harrington first introduced the effective instrumentation system for scoliosis

• For more than 30 yrs harrington distraction rod combined with posterior arthrodesis and immobilization in cast or brace for 6-9 months remained standard tretment

• Later it is replaced by multiple hook, sublaminar wire and pedicle screw

Disadvantage of advantage of newer harrington system instrumentation• Correction is achieved

with distraction so efficiency of correction is decreased

• Traction forces are applied at the end of the construct where the hooks are seated. If loads exceeds the strength of lamina fracture and loss of correction can result

• With distraction spine is elongated and loss of sagittal contour occurs

• Distraction does not deal with rotational component

• Provide multiple point of fixation to the spine and apply compression , distractionand rotation forces through same rod

• Donot require any post operative immobilization

• Better coronal plane correction and better control in sagittal plane

• Better transverse plane correction with pedicle screw

• Hypokphosis in thoracic spine reduced and lumbar lordosis preserved

Effects of distraction rod in lumbar spine. If contouring for lordosis is inadequate, lumbar spine can be flattened by distracting force. Also note kyphotic deformity just superior to distraction rod.

Correction maneuvres of spinal deformity

• Distraction on the concave side of a thoracic curve will decrease scoliosis and thoracic kyphosis

• Compression applied on the covex side of a lumbar curve will correct scoliosis and maintain lumbar lordosis

• Translating the apex of the curve in to a more normal position- rod derotation maneuver

• Pure translation using sublaminer wires or screw on cocave side

• Cantilever maneuver• Direct vertebral rotation with pedicle screw

Basic principles of fusion level and hook site placement

• AP, lateral and bending films are necessary• In the saggital plane all pathological curves must be

included. Instrumentation should not be stopped in the middle of a pathological saggital curve such as thoracolumbar junctionl kyphosis. The upper hook should not stopped at the apex of thekyphosis proximally

• in the transverse plane the instrumentation should extend to a rotational neutral vertebra

• Instrumentation should be stopped at the level above disc space neutralization, as determined on bending films as long as this level does not conflict with the saggital and transverse plane requirement

• The distal level should fall within the stable zone of harrington

Basic principle of the force generated by hook and its action on sagittal

plane1. Distraction forces ( forces directed away from

the apex of the curve ) decrease lordosis or contribute to kyphosis

2. Compression forces (towards the apex of the curve) decrease kyphosis or creat lordosis

3. To create kyphosis the concave side must be approached first

4. To create lordosis the convex side must be approached first and forces must be directed towards the apex of the curve

5. At the thoracolumbar junction , distractive forces should not be applied

a. Facectomy b. french bender c.forcep rocker used to seat the rod in implant

Set screw insertion in to the hook using Beale rod reducer

Deformity correction by CD HorizonLegacy spinal deformity system. a,.rod derotation b. rod bending

Rod compression and distraction, stabilization, and final tightening for CD Horizon Legacy spinal deformity system (see text). Decortication, rod contouring, and reduction.

Pedicle screw fixation

FIGURE 41-80 Pedicle channel classification (see text). (From Watanabe K, et al: A novel pedicle channel classification describing osseousanatomy, Spine 35:1836, 2010.)

Basic steps in identifying and placing a pedicle screw

1. Clearing the soft tissue2. Exposing the cancellous bone of the pedicle

canal by decortication at the intersection of the base of the facet and middle of the transverse process

3. Probing the pedicle4. Verifying the four walls of the pedicle canal by

probing or obtaining radiographic confirmation

5. Tapping the pedicle6. Placing the screw

Zindrick pedicle approach zoneCommon entry point in lumbar spinePosition of pedicle in sacrum

Complications of posterior scoliosis surgery

Early complications late complications1. Neurological injury 1. pseudoarthrosis2. Infection 2. loss of lumbar

lordosis3. Ileus 3.crankshaft

phenomenon4. Atelectasis 4. sup. Mesenteric

artery 5. Pneumothorax syndrome6. Dural tear 5. trunk

decompensation7. Wrong levels 6. late infection8. Urinary complications9. Vision loss

Treatment options for neuromuscular scoliosis

• Nonoperative- observation/orthotic• Operative- Luque rod instrumentation and

sublaminar wiring Sacropelvic fixation- galveston sacropelvic fixationUnit rod instrumentation with pelvic

fixation Iliac fixation with iliac screwsS2 iliac lumbopelvic screw placement

Indications for Correction and Posterior Spine Fusion in Patients with Poliomyelitis• Collapsing spinal deformity because of marked

paralysis• Progressive spinal deformity that does not

respond to nonoperative treatment• Reduction of cardiorespiratory function

associated with progressive restrictive lung disease• Decreasing independence in functional activities

because of spinal instability that necessitates use of the upper extremities for trunk support rather than for table-top activities• Back pain and loss of sitting balance associated

with pelvic obliquity, which frequently causes ischial pain and pressure necrosis on the downside of the gluteal region

Treatment of Congenital Scoliosis• Prevention of future deformity In situ fusion• Correction of deformity— Gradual Hemiepiphysiodesis and hemiarthrodesis Growing rod nonfusion Vertical expandable prosthetic titanium rib• Correction of deformity— acute Instrumentation and fusion Hemivertebra excision Osteotomy

Posterior fusion without instrumentation

• Allows for stabilization of a curve • Idealy done early for small curve to

prevent the curve from becoming unaaceptably large

• One level cephalad and one level cudad to the involved vertebra are included in fusion

Posterior fusion with instrumentation

• Slightly more correction can be obtained• Rate of pseudoarthrosis is low• Post operative cast / bracing least

unpleasant• Disadvantage are paralysis and

infection

Combined anterior and posterior fusion

• To treat saggital plane problems• To increase the flexibility of the scoliosis

by discectomy• To eliminate the anterior physis to

prevent bending or torsion of the fusion mass with further growth

• To treat curves with a significant potential for progression

Combined ant-post convex hemiepiphysiodesis

• Used for curves that are result of failure of fusion

• Correction of deformity relies on the future growth of the spine on the concave side

• Best for treating single hemivertebra that have not resulted in alarge curve at the time of surgery

• Appropriate in children <5 yrs with Progressive curve of < 500, with 6 segments or

less,with concave growth potential and no pathological congenital kyphosis /lordosis

Hemivertebra excision

• It can produce immediate correction of a congenital spine deformity

• It will remove the cause of and prevent further worsening of the deformity

• Is reserved for patients with pelvic obliquity or with fixed lateral translation of the thorax that can not be corrected by other means

Thank You