Catterall Classification (Legg-Calvé-Perthes)
Catterall classification (Catterall 1971) of Legg-Calve-Perthes disease — grades the childhood osteonecrosis of the femoral head by how much of the capital femoral epiphysis is involved at fragmentation.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Catterall group
- III — most of the epiphysis ("head within a head")
Result: Catterall group III: most of the epiphysis involved (the head within a head appearance); more extensive involvement.
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What the result means
- Group I / II
- Anterior epiphysis only, best prognosis (I); anterior and central with a sequestrum, pillars preserved (II).
- Group III
- Most of the epiphysis involved (the head within a head appearance). More extensive involvement.
- Group IV
- The entire capital femoral epiphysis involved. The most extensive involvement.
What you enter
- Catterall group
How this is calculated
Catterall A. The natural history of Perthes' disease. J Bone Joint Surg Br. 1971;53(1):37-53. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.