Scoliosis (Paediatric)
Summary
Scoliosis is a three-dimensional deformity of the spine characterised by lateral curvature >10 degrees (measured by Cobb Angle on X-ray) with associated vertebral rotation. The most common type in children is Adolescent Idiopathic Scoliosis (AIS), which typically presents in girls aged 10-15 years, is usually painless, and has no underlying cause. Scoliosis can also be congenital, neuromuscular, or syndromic. Clinical detection uses the Adam's Forward Bend Test (reveals rib hump). Management depends on curve size, skeletal maturity, and risk of progression: observation, bracing (Cobb 25-45°), or surgical posterior spinal fusion (Cobb >45-50°). [1,2]
Clinical Pearls
Adam's Forward Bend Test: The key clinical screening test. Patient bends forward; a rib hump on one side (due to vertebral rotation) indicates scoliosis. Positive test = refer for X-ray.
Cobb Angle: The radiographic measurement of curve severity. Measured on standing AP X-ray.
- less than 25°: Observation.
- 25-45° (Skeletally Immature): Bracing.
- >45-50°: Consider Surgery.
"Left Thoracic = Atypical": The typical AIS curve is RIGHT thoracic. A LEFT thoracic curve should prompt MRI to rule out intraspinal pathology (Syrinx, Cord Tumour).
Risser Sign: Grades iliac crest ossification (0-5). Indicates skeletal maturity. Lower Risser = more growth remaining = higher progression risk.
Demographics
- Prevalence: ~2-3% of adolescents have curves >10°. ~0.3% have curves >20°.
- Sex: Females > Males (7:1 for curves >20° requiring treatment).
- Age at Onset (Idiopathic):
- Infantile: 0-3 years.
- Juvenile: 3-10 years.
- Adolescent: 10-18 years (Most Common).
Risk Factors for Progression
| Factor | Higher Risk |
|---|---|
| Skeletal Immaturity | Risser 0-2 (more growth remaining). Pre-menarche. |
| Larger Initial Curve | Curves >25° more likely to progress. |
| Female Sex | 10x more likely to require treatment. |
| Curve Location | Thoracic curves more likely to progress than lumbar. |
By Aetiology
| Type | Notes |
|---|---|
| Idiopathic (80%) | No known cause. Subdivided by age of onset. Adolescent Idiopathic Scoliosis (AIS) is most common. |
| Congenital (~10%) | Failure of vertebral formation or segmentation (Hemivertebrae, Block Vertebrae, Bar). Present from birth. Associated cardiac/renal anomalies. |
| Neuromuscular (~5%) | Cerebral Palsy, Muscular Dystrophy, Spina Bifida. Long C-curve. Sitting posture problems. |
| Syndromic | Neurofibromatosis (NF1), Marfan Syndrome, Ehlers-Danlos. |
| Secondary | Limb length discrepancy (postural). Muscle spasm (antalgic). Tumour/infection. |
Lenke Classification (For AIS)
- Complex system describing curve type, lumbar modifier, and sagittal modifier.
- Used by surgeons to plan fusion levels.
| Condition | Key Features |
|---|---|
| Adolescent Idiopathic Scoliosis (AIS) | Painless. Right thoracic curve. Female. Teen. No neurology. |
| Congenital Scoliosis | Present from birth. Vertebral anomaly on X-ray. Screen for cardiac/renal anomalies. |
| Neuromuscular Scoliosis | Underlying neurological condition (CP, DMD). Long C-curve. Poor trunk control. |
| Syringomyelia (Syrinx) | Spinal cord cyst. Left thoracic curve. Neurological signs (hand wasting, sensory change). |
| Spinal Cord Tumour | Pain. Neurological signs. Atypical curve. Night pain. |
| Leg Length Discrepancy | Postural (not structural). Curve corrects when sitting. |
| Scheuermann's Kyphosis | Increased thoracic kyphosis (forward hunch). Wedging of vertebrae. |
| Postural (Functional) Scoliosis | Corrects on forward bending or lying down. No rotation. |
History
Examination
| Sign | Finding |
|---|---|
| Adam's Forward Bend Test | Rib hump on convex side (thoracic). Lumbar prominence (lumbar curve). |
| Shoulder Asymmetry | One shoulder higher than the other. |
| Waist Asymmetry | Unequal waist creases. |
| Scapula Prominence | One scapula more prominent. |
| Skin | Check for Café-au-lait spots (NF1), Midline hair/dimple (Spinal Dysraphism). |
| Neurology | Reflexes, Power, Sensation. Abnormality = MRI spine. |
| Lower Limbs | Leg length discrepancy. Check feet (Cavus foot in Charcot-Marie-Tooth). |
Radiology
| Test | Purpose |
|---|---|
| Standing Full Spine PA X-ray (EOS/Low Dose) | Measure Cobb Angle. Assess curve pattern. |
| Risser Sign (on AP X-ray) | Assess skeletal maturity (iliac apophysis ossification). |
| Supine Bending X-rays | Assess curve flexibility (pre-operative planning). |
| MRI Spine | ONLY if atypical features (Left thoracic, pain, neurological signs, young age, rapid progression, skin stigmata). Rule out Syrinx/Tumour. |
Cobb Angle Measurement
- Draw lines along superior endplate of upper end vertebra and inferior endplate of lower end vertebra.
- Measure the angle between perpendiculars from these lines.
Management Algorithm
SUSPECTED SCOLIOSIS
(Adam's Test Positive / Asymmetry)
↓
STANDING FULL SPINE X-RAY
Measure Cobb Angle + Risser Sign
↓
ANY RED FLAGS?
(Left thoracic, pain, neurology, skin)
┌────────────┴────────────┐
YES NO
↓ ↓
MRI SPINE IDIOPATHIC SCOLIOSIS
(Exclude Syrinx/Tumour) MANAGEMENT BY COBB ANGLE + MATURITY
↓
┌─────────────────────────────────────────────────────┐
COBB less than 25° COBB 25-45° COBB >45-50°
↓ ↓ ↓
OBSERVATION BRACING SURGERY
- X-ray every (if Risser 0-2, (Posterior Spinal
4-6 months skeletally immature) Fusion)
- Until skeletal - TLSO Brace (Boston)
maturity - Full-time wear
- Does NOT correct curve,
PREVENTS progression
↓
NO TREATMENT
(if mature and stable)
Treatment by Cobb Angle
| Cobb Angle | Skeletal Maturity | Management |
|---|---|---|
| less than 25° | Any | Observation. X-ray 4-6 monthly if growing. |
| 25-45° | Risser 0-2 (Immature) | Bracing (TLSO/Boston Brace). Full-time (16-23 hrs/day). |
| 25-45° | Risser 4-5 (Mature) | Observation (curve unlikely to progress once mature). |
| >45-50° | Any | Surgical Correction (Posterior Spinal Fusion with Instrumentation). |
Bracing
- Efficacy: BrAIST Trial showed bracing significantly reduces progression to surgical threshold in skeletally immature patients.
- Type: TLSO (Boston Brace) for main thoracolumbar curves. Charleston Night Brace (bedtime only, less evidence).
- Goal: Hold curve until skeletal maturity. Does NOT correct the curve.
- Compliance: Patient compliance is key. Often difficult for teenagers.
Surgical Treatment
- Indication: Cobb >45-50°, progressive despite bracing, significant cosmetic concern, risk of cardiopulmonary compromise (severe curves >70-80°).
- Procedure: Posterior Spinal Fusion (PSF) with pedicle screw instrumentation. Corrects curve, stops growth in fused segments.
- Newer: Anterior Vertebral Body Tethering (VBT) for select patients – growth-sparing (experimental).
Of Untreated Severe Scoliosis
- Cardiopulmonary Compromise: Severe thoracic curves (>70-80°) restrict lung expansion. Cor pulmonale. Rarely seen with modern treatment.
- Chronic Back Pain: More common in adults with significant untreated curves.
- Cosmetic Deformity: Psychological impact.
Of Treatment
| Bracing | Surgery |
|---|---|
| Skin irritation | Infection |
| Psychological (body image, compliance) | Implant failure / Pseudoarthrosis |
| Neurological injury (rare with IONM) | |
| Proximal Junctional Kyphosis (PJK) | |
| Loss of spinal flexibility |
- Mild Curves (less than 25°): Rarely progress after skeletal maturity. No treatment needed.
- Moderate Curves (25-45°): Bracing effective in ~70% if compliant. May progress if untreated.
- Severe Curves (>50° at maturity): Progress ~1°/year in adulthood. Surgery halts progression.
- Post-Surgery: Good functional outcomes. Most return to normal activities. Long-term fusion-related stiffness.
Key Guidelines
| Guideline | Organisation | Key Recommendations |
|---|---|---|
| Scoliosis Management | Scoliosis Research Society (SRS) | Observation less than 25°. Brace 25-45° if immature. Surgery >45-50°. |
| School Screening | USPSTF | Insufficient evidence for/against routine adolescent screening. |
Landmark Trials
- BrAIST Trial (2013): Bracing significantly reduces progression to surgical threshold (70% success vs 48% observation).
What is Scoliosis?
Scoliosis is when the spine develops a sideways curve instead of being straight. In most teenagers (called "idiopathic" scoliosis), we don't know exactly why this happens. It is more common in girls during the growth spurt.
How do you check for it?
We use the "Adam's Forward Bend Test" – when you bend forward, we look for a hump on one side of your back. We then take an X-ray to measure the curve.
Does it need treatment?
It depends on the size of the curve, your age, and how much growing you have left.
- Small curves: We just watch and repeat X-rays.
- Medium curves (and still growing): A brace worn daily can stop the curve getting worse.
- Large curves: Surgery (spinal fusion) may be needed to straighten the spine and stop progression.
Will it cause pain or problems?
Most teenagers with scoliosis have no pain. Very severe curves (rarely seen now) can affect breathing. With good treatment, most people live completely normal lives.
Primary Sources
- Scoliosis Research Society. Scoliosis Guidelines. srs.org.
- Weinstein SL, et al. Effects of Bracing in Adolescents with Idiopathic Scoliosis (BrAIST). N Engl J Med. 2013;369:1512-1521. PMID: 24047455.
Common Exam Questions
- Screening Test: "Clinical test for scoliosis?"
- Answer: Adam's Forward Bend Test (reveals rib hump).
- Measurement: "How is curve severity measured?"
- Answer: Cobb Angle on standing X-ray.
- Red Flag: "Atypical curve pattern suggesting underlying pathology?"
- Answer: Left Thoracic curve (MRI to rule out Syrinx/Tumour).
- Treatment Threshold: "When is surgery indicated?"
- Answer: Cobb Angle >45-50°.
Viva Points
- Risser Sign: Be able to describe (0-5 grading of iliac apophysis ossification) and its significance for progression risk.
- Bracing Mechanism: Explain that bracing prevents progression but does NOT correct the curve.
Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. Always consult appropriate specialists.