MSK MRI

Here is a full-thickness peripheral longitudinal tear of the posterior horn of lateral meniscus. There is an extra vertical line or layer in the periphery of lateral meniscus, indicative of far peripheral longitudinal tear. The tear is parallel and adjacent to the popliteus tendon. It is sometimes difficult to identify peripheral longitudinal tears in the posterior horn of the lateral meniscus b..

Longitudinal tears are diagnosed on MRI by the presence of a vertical line of increased signal intensity contacting the superior, inferior, or both surfaces of the meniscus. The longitudinal tear extends to the inferior meniscal surface and courses parallel to the long axis of the meniscus on corresponding PD FSE axial image. [Tear_04] case demonstrates vertically oriented increased signal inten..

Longitudinal tears almost always involve the posterior horn in both the medial and lateral menisci. They are diagnosed on MRI by the presence of a vertical line of increased signal intensity contacting the superior, inferior, or both surfaces of the meniscus. MR images showing vertically oriented increased signal intensity contacting both articular surfaces of the body and posterior horn of the ..

Left drawing shows a typical longitudinal tear that divides the meniscus into inner and outer halves, and the right drawing shows the expected appearance of the tear. Longitudinal tear with peripheral vertical orientation through the circumferential collagen fibers. Longitudinal tears run perpendicular to the tibial plateau and parallel to the long axis of the meniscus. Unlike horizontal or radi..

Beginning at the lateral aspect of the lateral compartment, the anteroinferior popliteomeniscal fascicle is seen to course from the inferior aspect of the lateral meniscus posteroinferiorly to blend with fibers of the popliteofibular ligament. ​​The posterosuperior popliteomeniscal fascicle is visualized medially to the anteroinferior popliteomeniscal fascicle as the popliteus tendon penetrates ..

The LM has a loose attachment to the joint capsule and to the femur and tibia by means of the meniscal ligaments and is not anchored to the lateral collateral ligament (LCL). Posterior oblique drawing demonstrates posterolateral restraints of the lateral meniscus including the posterosuperior popliteomeniscal fascicle (PSF), anteroinferior popliteomeniscal fascicle (AIF), meniscofemoral ligament..

PRLM has two attachment sites of the intertubercular region and the posterior slope of the lateral tubercle. Contiguous fat-suppressed PD coronal images with a posteroanterior direction demonstrate small, dark signal foci (white arrows) traversing the intertubercular crest and terminating on the medial tubercle, near the tibial attachment of the ACL. These green-yellow arrows show an intercondyl..

PRLM has two attachment sites of intertubercular region and posterior slope of lateral tubercle. This image shows an intercondylar crest insertion component among the two attachment sites. The PRLM inserts mainly in the intertubercular area. It is delineated on MRI as a dark signal line parallel to the tibial plateau on mid-sagittal images with an oblique course and longer length than other root..

The PRLM(lateral meniscus posterior root) provides secondary stability to the anterior cruciate ligament during pivot shift loading. The PRLM has unique features, including its course and configuration. An accurate anatomic understanding of the PRLM is clinically important because this region is difficult to fully visualize arthroscopically. PRLM has two attachment sites of intertubercular regio..

The anterior root of lateral meniscus is normally directed obliquely upward on sagittal images and frequently contains increased internal signal intensity. In this location, the increased signal intensity is sometimes referred to as “speckled.” The anterior root of the lateral meniscus differs from the anterior root of the medial meniscus because it often has a prominent fissured appearance simi..