This illustration provides a view of the tibial plateau (top of the shin bone) with the attached soft tissue structures. The menisci are two C-shaped fibrocartilage structures that sit atop the tibia in the knee joint and function as cushions or shock-absorbers during weight-bearing activity.
What is the meniscus?
The meniscus is a C-shaped shock absorbing cartilage cushion that sits between the femur and tibia in the knee (see figure). Each knee is equipped with two menisci – a medial meniscus on the inside of the knee and a lateral meniscus on the outside of the knee.
What causes a meniscus tear?
Meniscus tears can occur as an isolated injury or in combination with other injuries such as an ACL tear. When the meniscus tears in isolation, this is often the result of a twisting injury with the knee flexed. When the meniscus tears in an unstable or ACL-deficient knee, it is more likely the result of abnormal stress placed on the meniscus as the joint translates in the absence of the ACL.
What are the symptoms of a meniscus tear?
Meniscus tears cause pain on either the medial or lateral side of the knee, depending on whether the medial meniscus or lateral meniscus is torn. A torn meniscus often causes a clicking or catching sensation in the knee. In some cases, the knee may even become “locked” or stuck in a certain position when a portion of the torn meniscus flips into the joint.
How is a meniscus tear diagnosed?
Dr. Driscoll will discuss your symptoms with you and perform a thorough physical examination of your knee. X-Rays are usually obtained to rule out bone problems. If Dr. Driscoll suspects that you may have a meniscus tear or other soft tissue injury, an MRI is usually recommended. The MRI generates excellent images of the soft tissue structures around the knee, including the meniscus, and is usually sufficient to confirm the diagnosis (see figure).
A normal medial meniscus (left) and torn medial meniscus (right) are shown in two MRI examples above. The normal meniscus on these sagittal images (as if viewing from the side) appears as dark black triangles (left). The torn meniscus (right) appears irregular and is traversed by a light line representing the tear.
What is the treatment for a meniscus tear?
Treatment options include non-surgical and surgical alternatives. Non-surgical treatments include physical therapy, anti-inflammatory medications, and, in some cases, injections. When surgery is required, arthroscopic meniscus repair or partial meniscectomy is the preferred treatment. Some meniscus tears are not repairable due to the limited blood supply of the meniscal tissue. Other meniscus tears, particularly those close to the joint capsule, have better blood supply and are more likely to heal following repair. Dr. Driscoll will discuss your individual condition with you and create a treatment plan tailored for you.