Grading of meniscal injury

Lesions of the menisci on MRI are divided into four grades. Normal meniscus has uniformly low signal intensity on T2-weighted images (T2W). Grade I and II lesions can be a normal appearance of ageing in older patients.

Grade Description
Grade I small focus of increased signal intensity on T2W, that does not extend to the articular surface
Grade II linear area of increased signal intensity without extension to the articular surface
Grade III area of increased signal intensity that extends to the articular surface
Grade IV fragmentation of the meniscus


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