Magnetic Resonance Evaluation of the Meniscal Roots in the Knee

Purpose or Learning Objective: To provide an in-depth understanding of the anatomy and function of meniscal roots and their role in maintaining knee stability. We also demonstrate the magnetic resonance imaging (MRI) findings of root-related pathology, such as degeneration, tears, meniscal extrusion, cysts, ossicles, and osseous cystic lesions.

Methods or Background: The menisci are crucial for knee joint function. They are wedge-shaped, semilunar structures of fibrocartilage located between the femur and tibia, acting as shock absorbers and load distributors. The roots of the menisci arise from the anterior and posterior horns, attaching them to the central tibial plateau. These roots prevent radial stress displacement and can be subject to degenerative or traumatic disruption.

Results or Findings: Injuries to meniscal roots can lead to pain, meniscal extrusion, and osteoarthritis. MRI is an essential tool to diagnose meniscal root pathology, providing detailed images of the soft tissues. Radiologists should be familiar with the appearances of the posterior and anterior roots of both medial and lateral menisci and the differences between normal variants and pathology.

This review includes a comprehensive description of the MRI changes typical of degeneration and findings of tears, such as meniscal extrusion, meniscal root cysts, meniscal ossicles, and osseous cystic lesions, all of which suggest meniscal root pathology.

Conclusion: An accurate description of meniscal tears, articular cartilage evaluation, and associated injuries should be included in the MRI report. A thorough understanding of meniscal anatomy and variants is necessary for radiologists to diagnose meniscal root pathology accurately and provide the best treatment recommendations for patients. This knowledge can improve patient outcomes and aid in the decision-making process regarding surgical intervention.

Publication History

Article published online:
26 May 2023