Modified Noyes grading of the chondral injury
Chondromalacia can be divided into 4 grades by MRI, typically using fat saturated proton density sequences. The original Noyes grading system was based on arthroscopic findings. The modified Noyes system was published in 2009.
- Grade 0: normal cartilage
- Grade 1: increased T2 signal intensity of morphologically normal cartilage not oriented at 55° to the external magnetic field
- Grade 2A: superficial partial-thickness cartilage defect <50% of total articular surface thickness
- Grade 2B: deep partial-thickness cartilage defect >50% of total articular surface thickness
- Grade 3: full-thickness cartilage defect