The menisci, cartilage discs between the joint surfaces in the knee, play an important role in distributing stress across the curved surfaces of the knee. However, tears of the root of the meniscus have been increasingly recognized in recent years, which is why physicians at Baylor College of Medicine recently published a paper in the journal RadioGraphics that stresses the importance of recognizing and treating these tears.
"Tears at the root of the lateral or medial meniscus can be a cause of knee pain, and while a root tear might be suspected during an exam, an MRI scan is the best diagnostic modality of picking up these injuries," said Dr. Theodore Shybut, assistant professor of orthopedic surgery at Baylor and a co-author of the paper.
The medial meniscus is located on the inner side of the knee joint, and the lateral is located on the outside of the knee.
Lateral meniscal root tears often occur with knee instability associated with anterior cruciate ligament (ACL) tears. Shybut's research has shown that the lateral meniscal root is a secondary stabilizer of the ACL. Medial meniscal root tears can be associated with trauma, but also often occur in the setting of cartilage thinning and degenerative joint disease.
Biomechanical studies have shown a meniscal root tear is similar to not having a functional meniscus at all, which is associated with accelerated development of arthritis.
"The biomechanics research suggests that if you can repair the root and get it to heal, you may help postpone osteoarthritis of the knee on the medial side. On the lateral side, you are usually addressing instability," said Shybut.
In this new paper, Shybut and colleagues emphasize the importance of recognizing these injuries through MRIs, give tools for how to communicate the injury between radiologists and surgeons and also describe surgical technique and post-operative imaging.
"Raising awareness of these injuries is important so radiologists and surgeons are looking for them," said Shybut.
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