Normal Anatomy of Medial meniscus in MRI

Both horns are triangular in shape and have very sharp points.
The posterior horn is always larger than the anterior horn (figure).
If this is not the case than the shape is abnormal, which can be a sign of a meniscal tear or a partial meniscectomy.

Medial meniscus: The posterior horn is always larger than the anterior horn.

The posterior root is immediately anterior to the posterior cruciate ligament.
If it is missing on the sagittal images, then there is a meniscal root tear (figure).
The anterior horn has an insertion on the tibia and a second portion that travels from medial to lateral to connect to the anterior horn of the lateral meniscus ( intermeniscal or transverse ligament).

LEFT: normal medial meniscal root immediately anterior to the posterior cruciate ligament.
RIGHT: missing posterior root due to meniscal root tear.