This is Barry Bellosis, one of the musculoskeletal radiology fellows at Stanford University. 24 year old female presented to the ED with acute onset right knee pain. Concerned for lateral meniscus boccatile tear. This is on a different patient who underwent MRI knee without contrast. Here we can see the normal lateral meniscus. A normal meniscus appear as a low signal intensity structure on all sequences. On our sagittal images specifically, they appear as a bow-tie structure peripherally or opposing triangle as we can see here. A tear is defined as an abnormal signal reaching the articular surface. We also evaluate for any contour abnormalities to suggest the presence of a tear. Here on our right hand images, we can see this is the medial meniscus posterior horn. We can see this bright signal or hyper intensity in the posterior horn reaching the undersurface consistent with the tear. Just a slice medial to this, we can see that there is a truncated triangle also consistent with the tear. A specific type of meniscal tear is called a boccet handle, which is a longitudinal tear. It is called boccet handle because it resembles a handle of a boccet. It separates the central aspect of the meniscus from the periphery. This would be a longitudinal tear. A boccet handle would be the tear that's flipped medially just resembling a boccet handle. Here on our coronal T2 fat set imaging, we can see a tear of the medial meniscus right here with a displaced fragment here in the intercondylar notch. On our sagittal PD imaging, we can see this dark band just anterior to the posterior cruciate ligament. This is a double PCL sign which could be seen in the setting of boccet handle tear. This is also demonstrated in our sagittal T2 fat set imaging as here.

2nd Edition, CASE 27

2nd Edition

Knee

musculoskeletal radiology

lateral meniscus tear

MRI

bucket handle tear

double PCL sign