Scoliosis

Definition

• an apparent lateral curvature of the spine
• actually a triplanar deformity with lateral, anteroposterior and rotational components (Dickson et al., 1984)

Evaluation of the patient with scoliosis

History taking

• deformity
• when did it first appear
• is it progressive?
• Is there pain
• family history of spine deformity or neurologic disease?
• determine the status of growth
• menses begun
• pubic hair
• ask about other observations or treatment
• seen another doctor
• treatment given

Physical examination

Examination of Other Areas

• Skin
  • abN defects in the spine area (lipomas, hairy patches, hemangiomas or nevi)
  • cafe-au-lait spots (a sign of neurofibromatosis)
  • hyperelasticity - Ehlers-Danlos syndrome
• Heart
  • murmurs – sonar
• Uro-genital tract
  • horse-shoe kidney
  • sonar, IVP
• Ears
  • congenital abN
  • preauricular skin tags - Goldenhar’s syndrome
• Palate
  • high-arched palate - Marfan’s syndrome
  • cleft palate - congenital deformity
• Hands
  • congenital anomalies, joint hyperelasticity (Ehlers-Danlos & Marfan’s sy)
  • muscle weakness (e.g. clawing of fingers in syringomyelia)
• Hips
  • range of motion, especially for contractures
  • paralytic disorders - look for tightness of the extensors, flexors, adD, abD & ITB
• Feet
  • diagnosis of neuromuscular problems
  • high arches suggest Friedreich’s ataxia or Charcot-Marie-Tooth sy
  • clubfeet, vertical tali or heel varus - spinal dysraphism
  • presence of both foot deformity & spine deformity in the same patient -> either a NM disorder or spinal dysraphism (e.g., diastematomyelia, intraspinal lipoma, filum terminale)
• Pulmonary function testing
  • major reason for treating scoliosis preservation of lung capacity (especially thoracic scoliosis)
  • pulmonary function affected by the curve
  • serious error to use actual height for calculation
    • scoliosis causes loss of height & a falsely high value will be obtained
• FVC & FEV1 & ABG

Neurologic examination

• reflexes
• deep tendon (biceps, triceps, patellar and Achilles-tendon reflexes)
• superficial (abdominal)
• pathological (Babinsky)
• motor & sensory examination
• straight-leg raising
• Romberg test & finger-to-nose for any neuromuscular problem

Examination of the spine

• curve
  • area of the curve (e.g., right thoracic, or double right thoracic & left lumbar)
  • magnitude of the curve
• balance
  • deviation of a plumb line dropped from occiput or from 7th cervical vertebra to the gluteal cleft
  • measured in cm
• shoulder elevation (also measured in cm)
• prominence of one hip
• are the iliac crests level?

On forward bending toward the observer

• measured in cm or in degrees of deviation from the horizontal

Bending away from the examiner

• deviation to one side
  • suggests cord or cauda equina irritation
  • bone scan & myelography indicated to rule out tumours
• note whether there is pure scoliosis, pure kyphosis, pure lordosis or a combination of the above
  • rib hump due solely to rotation should never be called kyphoscoliosis
  • adolescent idiopathic scoliosis - lordosis of the thoracic spine, not kyphosis

Stage of development

• Tanner system
  • breasts & pubic hair development
  • Tanner 2 & 3 - rapid phase of growth spurt

Radiologic evaluation

Positioning

• standing views if can
• sitting or supine if can’t stand

Curve pattern

• reflexes
• deep tendon (biceps, triceps, patellar and Achilles-tendon reflexes)
• superficial (abdominal)
• pathological (Babinsky)
• motor & sensory examination
• straight-leg raising
• Romberg test & finger-to-nose for any neuromuscular problem

Measurement of Curve

Cobb technique

• first select end vertebrae of the curve
  • the most tilted from the horizontal
• double curvature
  • both curves measured
• transitional vertebra
  • upper end vertebra for the lower curve and the lower end vertebra for the upper curve
  • place only one line on this vertebra (upper and lower end-plates are parallel)

Cobb method / Risser-Ferguson method

Rib-vertebral angle (RVA)

• line perpendicular to the apical vertebral end plate & another line thru’ middle of the corresponding rib
• angle formed by the inter-section -> RVA

• RVA difference (RVAD)
  • difference between the values of the angles on the concave and convex sides of the curve
  • if initial RVAD > 20° -> progressive curve until proven otherwise

Measurement of Kyphosis & Lordosis

• on lateral view
• as important as AP x-ray
• Cobb technique applied

Evaluation of Rotation

• small curve without rotation -> postural
• length of the arthrodesis partly determined by the rotation

Nash & Moe method

• evaluation of pedicles on the convex side of curve
• grade I – grade IV

Pedriolle method

• more complicated
• in studies

Side bending films

• only preoperatively to determine which segment to fuse

Bone age determination

• in conjunction with clinical assessment (Tanner staging)

Risser grading

• ossification of the iliac crest apophyses on AP pelvis view
• starts anteriorly from ASIS & proceeds posteriorly towards PSIS
• divided into quarters & graded as Risser 1 to 4
• Risser 5 complete fusion of apophysis
• Grade 0 (no ossification) & 1 coincide with rapid growth

Vertebral ring apophysis

• at upper & lower margins of vertebral body
• fusion of the ring -> cessation of spinal growth

Pyle - Gruelich atlas

• L hand & wrist AP to compare with atlases
• to determine bone age

Special studies

Tomography

• better definition of congenital anomalies
• detection of osteoid osteomas - may produce scoliosis

Myelography

• suspicion of spinal cord tumour, spinal dysraphism, or any neurologic problems 2° to curvature
• always examine the entire spinal canal
• water-soluble myelographic techniques

CT Scan

• seldom useful in ordinary curvature problems
• highly useful for bone tumours, infections, spinal stenosis, and some fractures
• can be combined with water-soluble myelography(dysraphic problems, tumours, and cystic lesions)

MRI

• evaluation of spinal canal & its contents
• in all congenital scoliosis & infantile or juvenile idiopathic scoliosis
  • high incidence of dysraphism or intraspinal problems

Natural history

• 2x mortality rate then normal population
• << vital capacity if curve > 60°
• if curve > 60° - progression after growth stops

Nonstructural scoliosis

Postural Scoliosis

• children who do not voluntarily stand perfectly straight
• usually thoracic kyphosis and lumbar lordosis, but also scoliosis of mild degree

X-ray

• long curve, extending from one end of the spine to the other
• no rotation
• supine x-ray usually perfectly straight & bending films show no areas of contracture
• such curves do not progress nor become structural

Leg Length Discrepancy

• results in a curvature of the spine in the standing position
• functional or non-structural - no intrinsic stiffness of the curve in the spine
• disappears in sitting, lying down or if leg length is corrected
• does not become structural if presents for long period of time
• spend little time standing on our two feet with even weight

Hysterical Scoliosis

• emotionally disturbed teenagers develop a curvature of the spine

Physical examination

• constant in the upright & sitting position
• may or may not be present in the prone or supine position
• always absent while sleeping & under anaesthetic

X-ray

• long, sweeping, bizarre pattern curvature
• not associated with rotation on the x-ray or true rib hump on forward bending
• exclude spinal cord tumour or other neurologic pathology
• not to treat by orthopaedic methods (e.g., exercises, braces, or casts) & never by surgery
• psychiatric problem

Structural scoliosis
Idiopathic scoliosis

Definition

• scoliosis of unknown cause
• most common form of scoliosis
• all possible causes must be excluded (congenital, neuromuscular etc.)
• if painful -> further investigation (osteoid osteoma)
• three types depending on the age of onset

Incidence/prevalence

• 1.5 - 3%
• infantile 1%
• juvenile 10%
• adolescent 89%

Aetiology

• unknown
• multifactorial
• many theories

Infantile

• genetic tendency – multifactorial
• postural cause
  • plagiocephaly – flattened occiput after birth
• associated factors
  • CDH
  • heart defect

Adolescent

• familial pattern
  • autosomal or gender linked with incomplete penetrance
  • examine siblings
• too rapid growth
• paraspinal muscle weakness/abN

Presentation

• asymmetry of the back
  • noticed by parents
  • school screenings
    • Adams forward bending test
    • waist & feet together, knees straight, palms opposed
    • any positive sent for X-rays
    • expensive, but worthwhile as early bracing alters the natural Hx of ~

Infantile idiopathic scoliosis

Definition

• onset before 3 yrs of age
• 1 % of all idiopathic ~
• boys > girls
• curves – left thoracic or thoracolumbar

Progression

• 85 % non progressive
• 15 % progressive
  • if RVAD > 20° -> progressive
  • benign & malignant type

Treatment

Observation

• non progressive -> no treatment
• follow up with X-rays every 6/12

Bracing

• any curve > 35°
• any progressive curve
• serial cast first
• Milwaukee brace full time
• weaning according to correction
• child observed until maturity

Surgery

• if can’t control with brace
• usually malignant progressive type
• instrumentation without fusion
• rod under fascia
• protected in Milwaukee brace
• spinal growth can occur
• spinal fusion
• at adolescent growth spurt
• anterior & posterior fusion to avoid crankshaft effect

Juvenile idiopathic scoliosis

Definition

• onset between 3 yrs & puberty
• boys = girls
• 10 % of all idiopathic ~
• left thoracic curve in younger children
• double or R thoracic in older child
• intraspinal pathology common - MRI

Progression

• 1/3 non progressive
• 2/3 progressive
  • 50% managed with bracing
  • 50% needs surgery/li>

Treatment

Observation

• curve < 25°
• follow up every 4-6/12 with repeat standing x-rays

Bracing

• curve > 25°
• progressive curve
• Milwaukee brace
  • 24 hours a day
  • if curve maintained 20° or << -> weaning
    • out of brace 4 hrs -> x-ray
    • 3/12 later out for 6 hrs
    • continued until just night bracing
    • if still stable – out of brace
• continue observing until maturity

Surgery

• if progression in brace
• depending on age - instrumentation without fusion or fusion

Adolescent idiopathic scoliosis

Definition

• first detected at time of adolescent growth spurt
• girls > boys
• 89% of all idiopathic ~
• right thoracic or double R thoracic L lumbar curve usually

Progression

• > 5° (10°) increase from time of presentation
• risk factors
  • larger the curve (>20-29°)
  • double curve
  • growth potential available (Risser 0 or 1)
  • girls
  • family hx. of scoliosis, rotational prominence, decompensation

Treatment

• full Hx & clinical examination
• complete neurologic assessment
  • any sign of intraspinal pathology -> MRI
• exclude other possible causes
• standing AP & lateral X-rays of whole spine
  • 36 inch cassette
  • balance seen better
  • measure curves (Cobb’s)
  • unusual curve pattern (L thoracic) -> MRI
• evaluate growth potential
  • Tanner grading (menarche in girls, axillary hair in boys)
  • Tanner stage 2 indicates onset of adolescent growth spurt
  • Risser grading (iliac crest)

Observation

Growing child

• age, pre-menarche, no axillary hair, Risser sign < 3
• < 25° curve
  • follow up x-ray every 6-8/12 (< 20°)
  • x-ray 3-4/12 for larger curves
  • if progression > 5° from presentation -> non-operative rx
• > 30° curve -> non-operative rx

Near end of growth

• Risser sign > 3, post menarche, axillary hair
• up to 45° observe
  • follow up every 4-6/12
  • until cessation of growth

Non-operative Rx

• control curve & prevent progression
• cosmesis should improve

Electric stimulation

• muscles on convexity of curve
• used in past
• no effect on natural Hx.

Exercises, Manipulation

• no benefit – no role

Orthotic Rx. (bracing)

• in growing child
• > 30-40° curve or curve < 29° , but progressive
• alters natural hx. of scoliosis
• failure – if patient progress > 5° in brace or needs surgery

Contraindication

• completed growth
• curve > 45° or < 25° without progression

Milwaukee brace

• cervico-thoraco-lumbo-sacral orthosis
• moulded pelvic section
• 2 posterior & 1 anterior uprights connected to neck ring
• pads attached to uprights according to curve pattern

TLSO

• thoraco-lumbo-sacral orthosis
• underarm or lower type
• not used if apex above T8

Method

Full time wear (20 –22 hrs)

• out for bathing or athletic activity
• follow up every 4/12
• standing x-ray in brace
• measure for progression
• adjust for growth

Weaning from brace

• started at end of growth (no increase in height, Risser 4 or >, 12-18/12 post-menarche)
• standing x-ray at 4 hrs out of brace -> if no loss -> 4 hrs out of brace daily
• repeated every 4 months adding 4 hrs until night bracing
• night bracing for 6-12 month, then out of brace for 1 week & x-ray

Operative Rx

Indications

• child in a rapid growing phase with 40-45° curve
• progression to a curve of 40-45° under bracing
• mature adolescent with curve > 50-60°
• other factors
  • cosmetic appearance
  • decompensation
  • thoracic lordosis

Pre-operative evaluation

• full Hx. & clinical evaluation
• complete neurologic examination
• additional x-rays
  • lateral for saggital balance
  • bending views

Selection of fusion area

• identify curve pattern
  • analyse clinical appearance
  • standing & supine bending views
• single or double major pattern
  • all major curves need to be fused
  • compensatory curves not
• King’s classification
  • classification of thoracic curves into 5 types (type I – V)
  • based on location, apex, magnitude & flexibility
  • attempt to determine fusion levels
  • King type II & III most common
  • fusion must extend from a non-rotated vertebra cranially to a non-rotated vertebra caudally
  • the lower end vertebra must be the stable vertebra (bisected by the central sacral line)

Type I deformity

• S-shaped curve in which both the thoracic and the lumbar curves cross the midline
• lumbar curve usually larger and less flexible than the thoracic component
• double major or double primary pattern ---> both curves need to be included in the fusion area
• almost always T4 to L4

Type II curve

• S-shaped combined thoracic & lumbar double curve pattern
• thoracic curve greater in magnitude and less flexible than the compensatory lumbar curve
• lumbar curve must cross the centre sacral line
• only the thoracic curve needs to be fused

Type III

• pure thoracic curve
• compensatory lumbar curve never crosses the midline and much more flexible
• fusion of only the thoracic curve
• inferior level --> stable vertebra

Type IV curve

• long thoracic curve with the apex in thoracic spine, but its lower end vertebra in lumbar spine
• lower end vertebra typically L2, but rotation persists to L3 or even L4
• decompensation of the thorax to the right occurs
• important to distinguish type III pattern from type IV pattem because the latter needs a longer fusion and a different
• inferior level of fusion --> stable vertebra
• King et al did not describe or discuss primary thoracolumbar curves (apex at T12 or L2) or primary lumbar curves

“King V” pattern

• double major thoracic pattern
• identifying features
• a high left curve
• apex usually at T3, the upper end vertebra T1 or T2 the lower end vertebra T5 or T6
• a second right thoracic curve
• upper end vertebra T5 or T6; the apex at T8, T9, or T10 and the lower end vertebra at T11, T12, or L1, or even L2
• both curves “structural”
• full curves (not fractional) and lack complete flexibility on side-bending
• a “positive T1 tilt”
• a line drawn along the upper end plate of T1 higher on the left than on the right
• apical vertebra of the upper curve to the left of midline

Clinical evaluation

View of the patient from the front

• the hair is tied up, and the gown is pulled down or off --> neckline, trapezius area, and the shoulder balance seen clearly
• higher L shoulder
• trapezius area prominence or fullness more readily seen from the front than the back

Viewed from the side

• areas of abnormal lordosis and kyphosis
• kyphosis in the T1 to T5 area of particular concern --> extending the fusion up to T2 or T1

Viewing from the back

• overall balance
• Is the head centered over the pelvis? Are the shoulders level? Are the trapezius prominence areas symmetric?
• Is the thorax vertical or tilted? Is the thorax as a unit centered over the sacrum?
• L scapula prominence, trapezius fullness

Forward bending examination (best done with the examiner seated and the patient bending toward the examiner)

• rotational prominences and the amount of such prominence
  • look specifically at the high thoracic level (L), the low thoracic level (R), and the lumbar level (nil)
  • presence of high left thoracic prominence diagnostic of a structural left thoracic curve

Instrumentation

• corrects deformity
• adds stability & early mobilisation
• << pseudo-arthrosis

1^st generation

• • Harrington hook-rod system

2^nd generation

• • sublaminar wiring (Luque)

3^rd generation

• • allows 3 dimensional correction
  • no need for bracing
  • CD – pedicle screws, hooks & rod
  • TSRH, Moss Miami etc.

Safety

• monitoring possible – SSEP
• Stagnara wake-up test
• any change in neurology – reduce distraction or remove distraction rod
• cord problems with correction
  • Harrington technique – 0.23%
  • CDI – 0.60%
  • sublaminar wiring – 0.86%

Preservation of spinal mobility

• back pain after spinal fusion
• minimum number of segments must be fused

Congenital scoliosis

Definition

• curve d/t anomalous development of the vertebra
• anomalies present at birth - curvature at birth or developing much earlier in life
• receive less than optimum care - frequently progress to a serious degree
• rigid & resistant to correction - must not be allowed to progress - early fusion necessary

Classification

Failure of Formation

• partial (wedge)
• complete (hemivertebra)

Failure of Segmentation

• unilateral failure of segmentation (unilateral unsegmented bar)
• bilateral failure of segmentation (bloc vertebrae)

Miscellaneous

Mixed

Progression

• 25% - no progression
• 50% progresses significantly -> treatment required
• follow up at 6-month intervals until end of growth
  • high-quality X-rays
  • photographs
• malicious anomaly - unilateral unsegmented bar -> early fusion
  • total lack of growth on concave side

Associated congenital anomaly

• most frequently genitourinary tract -> IVP
• congenital heart defects -> listen for murmurs
• high frequency of spinal dysraphism
• check x-rays for interpedicular widening or midline bony spicules
  • any evidence of hidden neurologic disorder
  • hair patches, dimples, hemangiomata
  • abN of the lower extremities
    • flat feet, cavus feet, vertical tali, clubfeet
    • atrophy of one calf, smaller foot & asymmetric reflex

X-ray evaluation

• standing, sitting or supine AP & lateral
• tomograms to see deformity better
• MRI
  • always to exclude dysraphism

Orthotic Treatment

• no role
  • primary deformity in the bones - rigid
  • more difficult to treat than idiopathic or paralytic curves

Indications

• flexible curves in whom the curvature was primarily in non congenital vertebrae
  • three or four patterns

Goal

• must control the curve in an acceptable alignment
• main indication for bracing -> delay of surgery until a more optimal age
• if curve progresses despite orthosis -> fusion must be done
• Milwaukee brace

Surgical Treatment

• most important
• two questions:
  • what is the best procedure?
  • what is the best time for the procedure?

Posterior fusion

Aim

• prevention of progression rather than correction

Usually without instrumentation

• with instrumentation
  • >> risk of neurological damage
  • MRI evaluation for tethered cord
• correction obtained with Risser cast or traction occasionally
• abundant bone graft
  • thick fusion mass necessary to avoid bending of the fusion by the intact anterior growth plates

Anterior and posterior fusion

• to prevent bending of the fusion mass - crankshaft phenomenon
• if concave growth persists - progressive improvement of the curve

Convex hemi-epiphyseodesis

• to arrest convex growth
• must be < 5 yrs old – enough growth remaining
• contraindicated if kyphosis at the deformity
• combined anterior & posterior approach
• postop. cast 4/12 then Milwaukee brace for 18/12

Hemivertebra excision

• difficult & dangerous
• in rigid angulated scoliosis
• wedge osteotomy at the apex of a curve & fusion of the whole curve

Neuromuscular scoliosis
Preoperative Evaluation

Nutrition

• Weight for-height percentile
• Serum tests
  • total protein, albumin, Iymphocyte count

Respiratory system

• History
  • aspiration, pneumonia, number of respiratory illnesses
  • anatomic anomalies including tracheomalacia & tracheostomy tube
• Physical examination:
  • strength of cough, presence of rhonchi, stridor
• Diagnostic tests:
  • CxR, ABG, pulmonary function tests (developmental age > 4)

Hematologic tests

• PT/TT/PTT, CBC, Bleeding time (for patients on valproic acid)

Cardiovascular screening

• Duchenne muscular dystrophy:
  • ECG, CXR, cardiac ECHO
• Friedreich’s ataxia:
  • ECG, chest radiograph, cardiac ECHO if symptomatic or > 18 years old

Classification

• endorsed by the Scoliosis Research Society

Idiopathic

Infantile

• 0-3 years
• Resolving
• Progressive

Juvenile

• 4 years-puberty onset

Adolescent

• puberty onset to epiphyseal closure

Adult

• epiphyses closed

Neuromuscular

Neuropathic

• Upper motor neuron lesion
  • Cerebral palsy
  • Spinocerebellar degeneration
    • Friedreich’s
    • Charcot-Marie-Tooth
    • Roussy-Levy
  • Syringomyelia
  • Spinal cord tumour
  • Spinal cord trauma
  • Other
• Lower motor neuron lesion
  • Poliomyelitis
  • Traumatic
  • Spinal muscular atrophy
  • Myelomeningocoele (paralytic)
  • Dysautonomia (Riley-Day)
  • Other

Myopathic

• Arthrogryposis
• Muscular dystrophy
  • Duchenne (pseudohypertrophic)
  • Limb-girdle
  • Facio-scapulohumeral
• Congenital hypotonia
• Myotonia dystrophica
• Other

Congenital

Congenital scoliosis

Failure of formation

• Wedge vertebra
• Hemivertebra

Failure of segmentation

• Unilateral bar
• Bilateral (“fusion”)

Mixed

Associated with Neural Tissue Defect

• Myelomeningocele
• Meningocele
• Spinal dysraphism
  • Diastematomyelia
  • Other

Neurofibromatosis

Mesenchymal

• Marfan’s
• Homocystinuria
• Ehlers-Danlos
• Other

Traumatic

• Fracture or dislocation (non paralytic)
• Post irradiation
• Other

Soft tissue contractures

• Postempyema
• Burns
• Other

Osteochondrodystrophies

• Achondroplasia
• Spondyloepiphyseal dysplasia
• Diastrophic dwarfism
• Mucopolysaccharidoses
• Other

Tumor

• Benign
• Malignant

Rheumatoid disease

Metabolic

• Rickets
• Juvenile osteoporosis
• Osteogenesis imperfecta

Related to lumbosacral area

• Spondylolysis
• Spondylolisthesis
• Other

Thoracogenic

• Post-thoracoplasty
• Post-thoracotomy
• Other

Hysterical

Functional

• Postural
• Secondary to short leg
• Due to muscle spasm
• Other