• A scoliosis is an apparent lateral curvature of the spine
• It is a triplanar deformity with lateral, anteroposterior and rotational components
• Postural scoliosis is secondary to pathology away from the spine (e.g. short leg or pelvic tilt)
• Curvature disappears when patient sits down
• Structural scoliosis is a non-correctable deformity
• Vertebral rotation results in spinal processes swinging to concavity of curve
• Secondary changes occur to counterbalance primary deformity
• Most cases of structural scoliosis are idiopathic
• Can also result from bone, neurological or muscular disease

Clinical features

• A scoliosis shows a typical deformity with a skew back and rib hump
• The hip normally protrudes on the concave side
• The scapula normally protrudes on the convex side
• The level and direction of the major curve convexity should be noted
• Convexity of curvatures determines the nomenclature of the lesion
• e.g.  A right thoracic scoliosis has the thoracic spine convex to the right
• A balanced deformity keeps occiput in midline
• A fixed scoliosis become more obvious on flexion
• The younger the child and greater the curvature the worse the prognosis

Radiology

• Full length PA and lateral films of the spine are required
• Upper and lower ends of spinal curve can be identified
• Angle of curvature (Cobb's angle) can be measured
• Lateral bending view can assess degree of correctability
• Skeletal maturity important as scoliosis can progress during skeletal growth

Idiopathic scoliosis

• 80% of scoliosies are idiopathic
• Patients often have a family history
• Many patients have a trivial curvature
• About 0.2% of population have greater than 30° of curvature
• Age of onset defines three groups as adolescent, juvenile and infantile

Adolescent idiopathic scoliosis

• Occurs with an onset older than 10 years
• 90% patients are female
• Progression is not inevitable
• With curvature of less than 20° spontaneous resolution can occur
• Predictors of progression include young age, marked curvature and skeletal immaturity
• Main aim of treatment is to prevent mild deformity becoming severe
• If mild scoliosis with progression consider brace
• If greater than 30° and progressing operative intervention may be required
• Harrington rods used to reduce rotational deformity and lateral curvature

Juvenile idiopathic scoliosis

• Occurs with an onset between 4 and 9 years
• Relatively uncommon condition
• Prognosis is worse than adolescent group
• Spinal fusion may be necessary before puberty

Infantile idiopathic scoliosis

• Occurs with an onset less than 3 years
• Is a rare condition
• 60% patients are boys
• In 90% the deformity resolves spontaneously
• In those in whom progression occurs the curvature can be severe
• Associated with a high incidence of cardiopulmonary dysfunction

Osteopathic scoliosis

• Associated with hemivertebrae, wedged vertebrae and fused vertebrae
• Overlying tissue often shows angiomas, naevi  and skin dimples
• Scoliosis usually mild
• Before considering surgery need to exclude and meningomyelocele

Neuropathic / myopathic scoliosis

• Associated with polio, cerebral palsy and muscular dystrophy
• Scoliosis is typically long and convex towards side of muscle weakness
• X-rays with traction with assess the degree of correctability

Bibliography

Weinstein S L,  Dolan L A,  Cheng J C et al.  Adolescent idiopathic scoliosis.  Lancet 2008;  371:  1727-1537.