Grading (based on iliac crest divided into 4 quadrants)

Risser 1: 25% iliac apophysis ossification Anterior Superior iliac spine (anterolateral) Seen in prepuberty or early puberty

Risser 2: 50% iliac apophysis ossification Ossification extends halfway across iliac wing Seen immediately before or during growth spurt

Risser 3: 75% iliac apophysis ossification. Indicates slowing of growth

Risser 4: 100% ossification, with no fusion to iliac crest . Indicates slowing of growth

Risser 5: Iliac apophysis fuses to iliac crest. Indicates cessation of growth.

A 'Risser 0' (before Risser 1) and Risser 5 are simlar in that both show no ossification centres on X ray. The two can be destinguished by age - an adolescent with Risser 5 grading will show no open growth plates in the long bones, and older be than 16 (female) or 18 (male), while a child with a Risser 0 grading will still have open growth plates in most of the long bones.