Noyes classification

Noyes Classification

• 0: Normal articular cartilage
• 1a: Mild softening or discoloration of articular cartilage
• 1b: Severe softening or discoloration of articular cartilage
• 2a: Partial-thickness defect of <50% of the total thickness of articular cartilage
• 2b: Partial-thickness defect of >50% of the total thickness of articular cartilage
• 3a: Full-thickness articular cartilage defect with normal subchondral bone
• 3b: Full-thickness articular cartilage defect with erosion of subchondral bone

A classification like this is really a 'shorthand' for the doctor's notes, so that just a glance at past notes brings to mind an image of how far the arthritis had progressed when the note was made.

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Other relevant links on KNEEguru

A-Z Keywords -

• Outerbridge classification, Womac score, Crabmeat cartilage, Cartilage, Cartilage repair

Courses -

Dr Kevin Robert Stone - 2010 - Articular cartilage repair or regrowth

Dr Karen Hambly - 2008 - Articular cartilage damage

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