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 |
References
1. Stoller DW, Martin C, Crues JV 3rd, Kaplan L, Mink JH. Meniscal tears: pathologic correlation with MR imaging. Radiology. 1987 Jun;163(3):731–5.
2. Mesgarzadeh M, Moyer R, Leder DS, Revesz G, Russoniello A, Bonakdarpour A, et al. MR imaging of the knee: expanded classification and pitfalls to interpretation of meniscal tears. Radiographics. 1993 May;13(3):489–500.
3. Behairy NH, Dorgham MA, Khaled SA. Accuracy of routine magnetic resonance imaging in meniscal and ligamentous injuries of the knee: comparison with arthroscopy. Int Orthop. 2009 Aug;33(4):961–7.
4. Nikolaou VS, Chronopoulos E, Savvidou C, Plessas S, Giannoudis P, Efstathopoulos N, et al. MRI efficacy in diagnosing internal lesions of the knee: a retrospective analysis. J Trauma Manag Outcomes. 2008 Jun 2;2:4.
5. Crues JV 3rd, Mink J, Levy TL, Lotysch M, Stoller DW. Meniscal tears of the knee: accuracy of MR imaging. Radiology. 1987 Aug;164(2):445–8.
6. Rubin DA. MR imaging of the knee menisci. Radiol Clin North Am. 1997 Jan;35(1):21–44.