1. A PICTORIAL REVIEW EDUCATIONAL EXHIBIT ABSTRACT ID: IRIA – 1177 Authors: Dr Subarekha T B*, Dr Mohan Kumar Y*, Dr Murugesan A*, Dr Anbarasu A**, Dr Sivasubramanian B**, Institution: * Jansons MRI diagnostics Pvt Ltd, Erode. ** SRL diagnostics-Hi tech scans, RS puram, Coimbatore.

2. MENISCAL TEARS A tear is a well defined high signal area reaching up to the articular surface in at least 2 imaging planes or an area of distortion in the absence of prior surgery. Horizontal, Longitudinal, Radial, Root, Complex, Displaced TEAR NOT

3. HORIZONTAL TEAR- PARALLEL TO THE TIBIAL PLATEAU Coronal (a) and Sagittal (b) PDFS images demonstrating high signal area (arrow) in the anterior horn of lateral meniscus reaching the inferior meniscal surface parallel to the tibial plateau consistent with horizontal tear

4. Coronal PDFS (c) and T1(d) images demonstrating horizontal tear (arrow) of the body of medial meniscus HORIZONTAL TEAR

5. LONGITUDINAL TEAR - parallel to long axis of the menisci Coronal PDFS (a) and T1(b) images demonstrating high signal area (arrow) in the posterior horn of medial meniscus reaching the articulating surface perpendicular to the tibial plateau consistent with longitudinal tear

6. LONGITUDINAL TEAR Coronal (c) and sagittal PDFS(d) images demonstrating high signal area (arrow) in the posterior horn of medial meniscus reaching the articulating surface perpendicular to the tibial plateau consistent with longitudinal tear

7. LONGITUDINAL TEAR Coronal PDFS (c) and PD (d) images demonstrating high signal area (arrow) in the posterior horn of medial meniscus reaching the articulating surface perpendicular to the tibial plateau consistent with longitudinal tear

8. RADIAL TEAR perpendicular to the long axis of both tibial plateau and the meniscus. Extends from free edge towards periphery Sequential Coronal PD FSE (d and e )demonstrating cleft and marching cleft signs of radial tear (arrow). Truncated triangle sign is also seen in (e). A radial tear is seen along the free edge of the anterior horn of medial meniscus.

9. ROOT TEAR Sagittal (a) and coronal (b) PDFS images demonstrating high signal area (arrow) in the posterior root of medial meniscus consistent with root tear.

10. complex Coronal PDFS (a) and(b) images demonstrating complex tear with horizontal (straight arrow) and longitudinal (curved arrow)components of the body and posterior horn of medial meniscus. A paramniscal cyst (arrow) is seen adjacent the posterior horn in sagittal PDFS (c)image. COMPLEX TEAR Combination of two or more components

11. Coronal PD (a) and(b) images demonstrating complex tear with horizontal (straight arrow) and longitudinal (curved arrow)components of the body and posterior horn of medial meniscus. A paramniscal cyst (arrow) is seen adjacent the posterior horn in sagittal PD (c)image. COMPLEX TEAR

12. DISPLACED TEARS Displaced longitudinal tear – bucket handle tear Displaced horizontal tear – flap tear Displaced radial tear – parrot beak tear.

13. BUCKET HANDLE TEAR Longitudinal tear with central migration of the inner fragment (handle). Coronal PDFS and PD images demonstrating displaced central fragment of the medial meniscus consistent with bucket handle tear. The displace fragment is in the intercondylar fossa forming ‘fragment in the notch’ sign.

14. BUCKET HANDLE TEAR Sagittal PDFS (c) and PD (d) images demonstrating displaced central fragment (straight arrow) paralleling posterior cruciate ligament (curved arrow) forming double PCL sign.

15. BUCKET HANDLE TEAR Axial PDFS image (e) demonstrating displaced central fragment (arrow) in the intercondylar notch diagnostic of bucket handle tear. Sagittal PDFS (f) image demonstrating absent bow tie sign.

16. FLAP TEAR- Displaced horizontal tear. Sagittal (a) and coronal (b)PDFS images demonstrating displaced horizontal flap tear of the medial meniscus (arrow in a). There is horizontal flap tear of the posterior horn of medial meniscus with flipped meniscus in the intercondylar notch (arrow in b)

17. FLAP TEAR Axial (c) and sagittal (d)PDFS images demonstrating displaced horizontal flap tear of the lateral meniscus. There is horizontal flap tear of the posterior horn of lateral with flipped meniscus anterior to anterior horn.

18. FLAP TEAR Coronal (e) and sagittal (f)PDFS images demonstrating displaced horizontal flap tear of the medial meniscus. There is horizontal flap tear of the body of meniscus (arrow) with displaced fragment superior to posterior horn.

19. References: Jie C. Nguyen, MS Arthur A. De Smet, Ben K. Graf, Humberto G. Rosas. MR Imaging–based Diagnosis and Classification of Meniscal Tears. RadioGraphics 2014; 34:981–999. Arthur A. De Smet. How I Diagnose Meniscal Tears on Knee MRI. AJR 2012; 199:481–499. Shetty D S, Lakhkar B N, Krishna G K. Magnetic resonance imaging in pathologic conditions of knee. Indian J Radiol Imaging 2002;12:375-81. Prasad A, Brar R, Rana S. MRI imaging of displaced meniscal tears: Report of a case highlighting new potential pitfalls of the MRI signs. Indian J Radiol Imaging 2014;24:291-6.