Adolescent Idiopathic Management



Curves < 20o observation only at 3-6 month intervals depending on growth rate 


Non Operative Management / Bracing 


Never brace curves if patient Risser 4 or 5 




1.  Risser 0-2 (growth potential)


2.  Curve >30o adolescent


3.  Curve >25o with progression (5o in six months)


4.  < 10 years old

- very young with high progression potential

- high risk crankshaft if operate


5.  Willingness to comply




Angle                      High Growth Potential                Lowth Growth Potential

<20°                                   observe                               observe or DC

20°-30°                               observe/brace                     observe

30°-45°                               brace                                  observe

>45°                                   surgical                               surgical / observe




Will control curve only

- end result is initial curve + 5o


Brace should be customised to patients curve 

- designed to prevent progression NOT to achieve correction 

- generally see a moderate amount of correction when using the brace

- then slow steady progression of curve back to original magnitude during weaning 

- best curves to brace are those < 40o


Bracing complications


Failure to prevent progression

Skin irritation

Pressure areas

Abdominal discomfort, eating habit disruption

Cast syndrome - SMA / duodenal obstruction



Milwaukee Brace  / CTLSO


Best for curves with apex above T8 

- three point fixation technique 

- less efficacious for curves > 40o


Consists of 

- well moulded pelvic piece above the iliac crests (most important)

- two posterior uprights and one anterior upright 

- neck piece with plastic throat mould anteriorly and two occipital pads posteriorly         

- thoracic pad placed over the apex of convexity of curve 

- lumbar pad over TP between lowest rib and iliac crest on concave side 

- active correction by muscle contraction pulling body away from pads




23 out of 24 hours a day

- result dependant on time in brace


Need to check regularly and readjust after 1-2 weeks 

- Xray on 6 month basis 

- if progresses > 45o then surgery


Aim for 30-50% correction in first 6 months 

- if not achieved consider surgery 




Once skeletal maturity / Risser 4 / full height 



- 20 hours for 4 months 

- 16 hours for 4 months 

- 12 hours for 4 months 

- night time only for 4 months 


TLSO (Under arm or Boston Brace)


If apex < T8 


Higher compliance 

May not be as efficacious in holding correction 

Made from cast


Operative Management




1.  Immature / Risser 1 /2

- Cobb > 40o with documented progression

- peak height velocity

- will progress 1o per month

- need to stabilise early


2.  Mature

- T > 45 - 50o

- TL or L > 30o with marked rotation

- double major > 50o

- significant coronal imbalance

- cosmetic deformity

- failure bracing


This curve will progress slowly

- patient has time to make up mind




Solid arthrodesis that prevents progression

Balanced spine

Correction of deformity

Prevent respiratory compromise




1.  Most curves 

- posterior instrumented fusion


2.  Lumbar curves

- anterior instrumented fusion


3.  Large curves > 70o / young patients

- anterior and posterior surgery




Fuse the structural curve with minimum segments

- to stable vertebra

- minimise the levels (preserve motion segments)

- avoid to L5 and above T1 (may increase pain)

- if fuse to L5, only 1 motion segment left, risk LBP


Correct curve in sagittal and coronal planes


Best to wait til 10 - 12 years to avoid crankshaft


Structural Curve


1.  Largest curve

2.  One to which trunk shifted

3.  Least correction on AP lateral bending Xray

4.  Pedicles rotated


Posterior Instrumented fusion


Multisegmental Hook and Pedicle screw systems

- allows for correction via Compression / Rotation / Distraction


Crankshaft phenomenon



- seen in young child with high growth potential

- pre PHV surgery or with open triradiates

- pivot on posterior fusion

- vertebral bodies and discs bulge towards convexity



- get loss of correction, increase in rotation, recurrence of rib hump


At risk

- Risser 0

- girls < 10

- boys < 13


Specific Surgery


Lenke Type 1

- main thoracic

- posterior stabilisation

- usually limit to T4 as shoulders equal


Scoliosis Fusion Long Thoracic


Lenke Type 2

- double thoracic / MT and PT

- need to instrument to T2

- equalise shoulders


Scoliosis Fusion Double Thoracic


Lenke Type 3

- double major / MT and TL/L

- long posterior instrumented fusion


Lenke Type 4

- triple major

- very long posterior instrumented fusion


Lenke Type 5

- thoracolumbar / lumbar curve

- can fuse short curve this through bed of T9 / T10 rib

- otherwise posterior instrumented fusion


Scoliosis Lumbar Curve Fusion


Lenke Type 6

- TL > MT structural

- long posterior instrumented fusion


Technique Posterior Instrumented Fusion





Cell saver

- accumulate large blood loss

- often large exposure

Xmatch blood

2 x milled femoral head allograft 

Spinal monitoring / SSEP's

- needles scalp / hands / feet

- begin pre-op once asleep as baseline


Pedicle screws / TP hooks / rods available

Post op ICU bed especially neuromuscular




4 Poster Bed

Protect eyes, knees, elbows

No pressure on abdomen / reduce venous bleeding




Posterior approach

- betadine pack buttocks

- midline incision

- divide thoracolumbar fascia midline

- split apophysis with knife (if present)

- subperiosteal elevation strap muscles

- use diathermy, cobb

- sequentially pack with rolled up packs to control bleeding


Lumbar spine

- expose facet joints and transverse processes

- don't go between transverse processes laterally as nerve roots here

- pedicle screws inserted bilaterally bottom 3 pedicles



- TP hooks above

- pedicle hooks below

- compress


2 x rods prebent in sagittal plane

- correct coronal malignement and rotation as able

- may use sublaminar wires if large long curve

- midsection of curve in concavity

- tie over rod and tighten to correct


Decorticate lamina, add bone graft along each side




Technique Anterior Fusion




Large lumbar curve in young patients 

- skeletally immature patient to achieve growth arrest and prevent crankshaft


Any lumbar curve to decrease fusion length

- this is debatable


Large / rigid curve to achieve mobility 

- severe curves >70o

- supplement posterior fusion




Fewer levels instrumented 

Better correction of rotation

Large surface for fusion

Fusion under compression

Use rib as bone graft




Requires anterior approach

Does not produce lumbar lordosis 

Respiratory problems (need chest drain)

Need to divide segmental vessels




Supine, rolled

- curved right sided approach

- remove 9th rib (save for bone graft)

- through bed of rib

- identify peritoneum, stay outside

- take down diaphragmatic crura

- divide segmental vessels, remove discs

- unilateral screws and rod

- repair diaphragm, close over ICC


Endoscopic Anterior Instrumentation



- reduced blood loss and pain

- better scars and cosmesis



- technically difficult

- respiratory problems / deflate lung


Growing rods




Growing children / open triradiate cartilage

- avoid fusion / crankshaft phenomen

- biannual surgery

- high complication rate 50%

- hook dislocation

- rod breakage


Costoplasty / Thoracoplasty




Partial excision of 5 or 6 ribs from the TP to posterior axillary line 




Corrects the rib hump 

Cosmetic procedure

Good source of graft 

Does not affect the post op morbidity or pulmonary function


Complications G. Coe SRS Report 2006






0.32% in posterior corrections (SRS) in adolescents 

- 2% in adults 

- highest in congenital curves



- SSEP's monitoring in all idiopathic and congenital curves 

- wake - up test in suitable patients (difficult in children)



- stimulate in legs, readings in cortex

- avoid inhalation anaesthetics

- time delay as must average amplitudes and reduce background noise

- issue if lose > 50% amplitudes


If lose SSEP's

- avoid hypotension

- transfuse Hb if low

- check electrodes

- wake up test

- give steroids

- reverse correction

- remove instrumentation


Infection 1.35%


Prophylaxis warranted 

Late chronic infection with Proponiobacterium acnes 


Respiratory 1.6%


- atelectasis


PE 0.02%


Death 0.03%


Ileus - very common


Blood Loss 


Avoided with

- autologous blood 

- cell savers 

- hypotensive anaesthesia

- autotransfusion

- often blood loss that contributes to neurological compromise 


Incorrect fusion levels / wrong level surgery


SIADH secretion 

- decrease UO night of surgery

- steady improvement 2-3/7





- 1% overall

- instrument failure 


Crank shaft Phenomena 


In rapidly growing child after posterior fusion

- spine will rotate as the bodies grow anteriorly

- thus if child with significant growth then add anterior discectomies and fusion


Other solutions

- posterior growing rods

- anterior staples / guided growth


Sagittal malalignment 

- loss of lumbar lordosis

- flat back / loss of thoracic kyphosis


Back Pain 


Related to fusion below L4 and loss of lumbar lordosis 


Levels and back pain

- L5 - 80%, L4 - 60%

- L3 - 40%, L2 - 20%


Late infection - low virulence organism




Gothenburg Sweden 1968

- 23 year follow-up post fusion with instrumentation

- preop Cobb 62°; postop 33°; last followup 37°

- same series had 127 patient braced

- prebrace 33°, best brace position 30°, last followup 38°