Define Scoliosis. Describe its classification, management and complications.

Definition

Scoliosis is a lateral curvature of the spine with vertebral rotation (a three-dimensional deformity), defined by a Cobb angle > 10°. A structural scoliosis is a fixed curve with vertebral rotation that does not correct on bending, whereas a non-structural (postural) scoliosis is a flexible curve secondary to another cause (leg-length discrepancy, pain/spasm) that corrects on removing the cause.

Classification / Causes

The commonest form is idiopathic scoliosis (adolescent idiopathic scoliosis being the most frequent, typically in adolescent girls). Other causes: congenital (vertebral anomalies — hemivertebra, failure of segmentation), neuromuscular (cerebral palsy, poliomyelitis, muscular dystrophy — a long C-shaped collapsing curve), and syndromic/other (neurofibromatosis, Marfan’s).

The Cobb angle is measured between the end-plates of the most-tilted (‘end’) vertebrae of the curve, using perpendiculars — the standard measure of curve severity.

Clinical Features & Assessment

Often a painless deformity noticed as asymmetry — uneven shoulders or waist, a prominent scapula, or a rib hump on the forward-bending (Adam’s) test (the rotation makes the ribs prominent on the convex side). Assess for leg-length discrepancy (to exclude postural curves) and for neurological signs (which suggest an underlying cord/neuromuscular cause). Curve magnitude is measured as the Cobb angle on a standing radiograph.

Management

• Treatment depends on the cause, curve magnitude and skeletal maturity (remaining growth).
• Small curves (< ~20–25°) are observed with serial radiographs.
• Moderate curves (~25–40–45°) in a still-growing child are treated with a brace to prevent progression.
• Large or progressive curves (> ~45–50°) are treated by surgical correction and instrumented spinal fusion. Congenital and neuromuscular curves are managed according to their cause. Untreated large curves can impair cardiorespiratory function.

Complications of Untreated Curves

A large, progressive scoliosis is not merely cosmetic: severe thoracic curves reduce the volume of the chest and can cause restrictive lung disease and, ultimately, cardiorespiratory compromise, while the deformity itself causes back pain, a poor body image and difficulty with seating (particularly in neuromuscular curves). Neuromuscular and congenital curves tend to progress even after skeletal maturity, which is why they are monitored and treated on their own criteria rather than those used for idiopathic curves.

• Lateral curvature + rotation of the spine; Cobb angle > 10°; structural vs postural.
• Commonest = adolescent idiopathic; also congenital, neuromuscular, syndromic.
• Rib hump on Adam’s forward-bend test; Cobb angle measures severity.
• Observe small curves; brace moderate curves in growing child; fuse large/progressive curves.
• Progression greatest during the growth spurt — monitor immature spines closely.