What is Scoliosis?
Scoliosis is a condition characterized by an abnormal sideways curvature of the spine. Rather than running straight down the center of the body, the vertebral column curves in an S-shape or C-shape. The condition can affect the thoracic spine (mid-back), lumbar spine (lower back), or both regions. When present in the thoracic spine, scoliosis may also cause rotation of the vertebrae, which can create a rib prominence or "rib hump" visible from behind.
Scoliosis is classified by severity using the Cobb angle, measured on X-ray. A curve exceeding 10 degrees is considered scoliosis; curves between 10 and 25 degrees are mild; 25 to 40 degrees are moderate; and greater than 40 degrees are severe. The severity influences symptom development and treatment decisions.
In Singapore, scoliosis detection often occurs during school screening programs or routine medical examinations. Some people remain completely asymptomatic throughout life, while others develop pain or functional limitations depending on curve severity, location, and progression. Understanding scoliosis type is crucial for appropriate management.
How Does Scoliosis Develop?
Scoliosis develops through various mechanisms depending on its type. In idiopathic scoliosis (most common), the exact cause remains unknown, though genetic factors appear to play a role. The condition often becomes apparent during the adolescent growth spurt, when rapid bone lengthening can cause or worsen curvature.
Degenerative scoliosis develops in adults when discs degenerate, facet joints develop arthritis, and vertebrae slip or tilt relative to one another. Spinal imbalance develops gradually over years. Other forms develop differently—congenital scoliosis results from vertebral malformations present at birth; neuromuscular scoliosis develops in people with conditions affecting muscle control; and syndromic scoliosis occurs alongside genetic disorders.
Progression varies considerably. Some adolescent curves remain stable throughout life, while others progress significantly during the growth period. Adult-onset scoliosis typically progresses more slowly than adolescent forms. Early detection allows monitoring and intervention to prevent severe deformity.
Symptoms and Physical Signs of Scoliosis
Many people with scoliosis have no symptoms, particularly if the curve is mild. Detection often occurs incidentally during routine examinations. When symptoms occur, they vary depending on curve severity and age of onset:
Physical Signs (visible):
- Uneven shoulders, with one shoulder higher than the other
- Prominent shoulder blade on one side
- Uneven waist, with asymmetrical waist creases
- One hip higher than the other
- Rib hump (visible prominence when bending forward) caused by vertebral rotation
- Body leaning to one side
Symptoms (when present):
- Back pain (more common in adults and degenerative scoliosis than in adolescents)
- Fatigue in the back muscles after prolonged activity or standing
- Breathing difficulty (rare, only in severe thoracic curves that compress the lungs)
- Reduced exercise tolerance
The Adam's forward bend test is a screening tool: when a child bends forward with arms hanging, an abnormal rib prominence becomes visible if scoliosis is present.
Types of Scoliosis
Idiopathic Scoliosis (Most Common):
No identified cause; accounts for approximately 80–90% of all scoliosis cases. Often appears during adolescence (ages 10–18), particularly during rapid growth spurts. More common in females. Genetic predisposition appears to play a role, as family history increases risk.
Degenerative (Adult-Onset) Scoliosis:
Develops in adults, usually after age 50, from age-related degeneration of discs and facet joints. Often associated with spinal stenosis and vertebral imbalance. Spinal stenosis can occur alongside degenerative scoliosis, causing leg pain in addition to back pain.
Congenital Scoliosis:
Results from abnormal vertebral formation during fetal development. Present at birth. Curves may progress during growth if vertebral malformations are unbalanced. Early detection and monitoring are critical.
Neuromuscular Scoliosis:
Develops in people with conditions affecting neuromuscular control, such as cerebral palsy, muscular dystrophy, spinal cord injuries, or myopathies. Often progresses rapidly and can be severe. Medical management of the underlying condition is essential.
Syndromic Scoliosis:
Associated with genetic disorders such as Marfan syndrome, Ehlers-Danlos syndrome, neurofibromatosis, or osteogenesis imperfecta. Often requires specialized management given associated spinal and connective tissue abnormalities.
Causes and Risk Factors
Idiopathic scoliosis (most common form) has no identified single cause, though research suggests:
Genetic factors:
Family history of scoliosis increases risk
Neuromuscular imbalance:
Possible asymmetry in spinal muscle development
Growth-related factors:
Rapid growth during adolescence may unmask latent curvature
Hormonal factors:
Estrogen may influence ligament laxity and curve progression
Risk factors for progression include young age at diagnosis, female gender, significant initial curve, and pre-menarchal status in girls.
For degenerative scoliosis, risk factors include age, prior spinal surgery, smoking, sedentary lifestyle, and osteoporosis. Other types have specific risk factors related to their underlying causes.
How is Scoliosis Diagnosed?
Diagnosis combines clinical assessment and imaging:
Physical examination:
Visual inspection for asymmetry; Adam's forward bend test to assess for rib hump; measurement of shoulder and hip height
Medical history:
Age of onset, family history, symptom progression, and associated conditions
X-ray (primary imaging):
Allows measurement of Cobb angle and assessment of curve severity and location
Full-spine X-rays:
Taken standing to assess overall spinal alignment and balance
MRI:
Reserved for suspected neurological involvement, unusual curve patterns, or syndromes associated with intraspinal anomalies
CT scan:
May be used to assess bone anatomy in complex cases
Non-Surgical Treatment Options
Treatment depends on curve severity and skeletal maturity:
Observation:
For curves less than 25 degrees in growing children or mild curves in adults. Regular monitoring (usually every 4–6 months) ensures curves do not progress unexpectedly.
Bracing:
Typically recommended for curves between 25 and 45 degrees in growing children to prevent progression until growth completion. Braces do not correct existing curvature but halt progression in approximately 80% of cases. Full-time (23 hours/day) wear is most effective.
Physiotherapy:
Specialized techniques such as Schroth method (a three-dimensional exercise approach) may improve posture and breathing, reduce pain, and provide psychological benefit. Core strengthening helps support the spine.
Pain Management (primarily for adults):
NSAIDs, heat therapy, and physical therapy help manage pain associated with degenerative scoliosis. Activity modification may reduce symptoms.
When is Surgery Considered for Scoliosis?
Surgery is typically considered when:
- Curves exceed 40–45 degrees in adolescents, regardless of symptoms
- Curves are progressing despite bracing
- Curves cause functional limitation, cosmetic concern unacceptable to the patient, or breathing compromise
- Adult degenerative scoliosis causes pain, neurological symptoms, or instability unresponsive to conservative management
Surgical options include:
Osteotomies or releases:
For very rigid or severe curves; involves cutting bone or releasing ligaments to allow curve correction
Recovery and What to Expect
Non-surgical management is ongoing. Patients undergoing bracing require regular follow-up and monitoring. Once skeletal maturity is achieved (typically after adolescent growth completion), bracing can be discontinued.
Post-surgical recovery from fusion:
- Hospital stay: Typically 2–3 days
- Return to light activity: 3–6 weeks
- Return to normal activity: 3–6 months
- Complete bone healing: 12–18 months
Modern surgical techniques, including robotic spine surgery, improve precision during complex scoliosis corrections, potentially reducing complications and improving outcomes. Robotic guidance helps surgeons achieve better alignment and screw placement.
Rehabilitation is essential post-surgically. Physical therapy focuses on restoring mobility, strength, and endurance. Most patients experience improved cosmetics and reduced pain post-operatively.
Frequently Asked Questions
Q1: Does scoliosis always require treatment?
A. No. Many people with mild scoliosis (less than 25 degrees) remain asymptomatic throughout life and require only periodic monitoring. Treatment depends on curve severity, age, progression rate, and symptoms. Your physician will recommend appropriate management based on your specific situation.
Q2: Can scoliosis improve without surgery?
A. Existing curvature cannot be reversed without surgery, but conservative management (observation, bracing, physiotherapy) is often sufficient to prevent progression and maintain function. Adolescent curves sometimes stabilize naturally. Adult degenerative scoliosis may improve with pain management and exercise.
Q3: Is scoliosis hereditary?
A. Idiopathic scoliosis tends to run in families, suggesting genetic predisposition. Having a family history increases risk, though not all relatives develop scoliosis. If you have scoliosis, your children may benefit from screening, particularly during adolescence.
Q4: Can pregnancy worsen scoliosis?
A. Pregnancy typically does not worsen underlying scoliosis curves, though pregnancy-related back pain may increase due to weight gain and postural changes. Women with scoliosis generally tolerate pregnancy well. Your surgeon will advise if you are considering pregnancy after fusion surgery.
Q5: Will scoliosis affect my breathing?
A. Only severe thoracic scoliosis (curves exceeding 70–80 degrees) typically causes breathing limitation by compressing the lungs. Mild to moderate curves do not affect lung function. Breathing exercises and physiotherapy may help optimize respiratory function in those with larger curves.
This page contains educational information only and is not a substitute for professional medical advice. If you or your child have suspected scoliosis, consult Dr. Huang Yilun or another qualified spine specialist for proper evaluation and management.
Dr. Huang Yilun is an Orthopaedic Consultant and Spine Surgeon at Total Orthopaedic Care and Surgery, Novena Medical Centre, Singapore. Contact Dr. Huang Yilun to schedule a consultation.