Risser Sign (Skeletal Maturity)
Risser sign (US grading, 0-5; Risser 1958) - skeletal-maturity staging by the ossification and fusion of the iliac crest apophysis, used in scoliosis to gauge the remaining growth potential (and the likelihood of curve progression).
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Risser grade
- Grade 5 - ossified and fused (mature)
Result: Risser grade 5: complete ossification and fusion of the apophysis to the iliac crest; full skeletal maturity.
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Grade 0
- No ossification of the iliac apophysis; skeletally immature, maximum growth potential remaining.
- Grades 1-3
- About 25% / 50% / 75% ossification of the iliac apophysis; growth potential decreasing.
- Grade 4
- 100% ossification of the apophysis, but not yet fused; little growth remains.
- Grade 5
- Complete ossification and fusion to the iliac crest; full skeletal maturity.
What you enter
- Risser grade
How this is calculated
Risser JC. The iliac apophysis: an invaluable sign in the management of scoliosis. Clin Orthop. 1958;11:111-119. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.