Scoliosis

Lateral curvature of the spine in an otherwise healthy person

Early onset scoliosis

 Infantile

0–3 years

 Juvenile

3–10 years

 Adolescent

> 10 years

Apical vertebra

At the apex of the curve, which is usually horizontal on an anteroposterior erect radiograph

Curve direction

Described by direction of convexity (note that spine surgeons frequently use radiographs as if seen from behind—the opposite of convention)

End vertebrae

Most tilted with respect to horizontal plane of erect radiograph above and below apical vertebra

Cobb angle

Angle between the apical vertebrae (an analogous system may be used for the measurement of kyphosis)

Risser sign

Classification of five stages of the development of the iliac apophysis on an anteroposterior film of the iliac crests (as seen on an anteroposterior radiograph of the spine). The apophysis develops from lateral to medial before fusing: 0, no apophysis; 1, 25%; 2, 50%; 3, 75%; 4, 100%; 5, closure

Lordosis

Reverse curve of spine (opposite of kyphosis)

Structural curve

A curve which does not correct on side-bending

Compensatory curve

A curve which does correct on side-bending