What is the Difference Between Medial and Lateral Meniscus Tear

The key difference between medial and lateral meniscus tear is that medial meniscus tear occurs on the inner side of the knee joint, while lateral meniscus tear occurs on the outside of the knee joint.

A meniscus tear is an injury to a part of the knee called a meniscus. It is a common injury. The two crescent-shaped, thick, rubbery menisci are shock-absorbing cartilage in the knee joint. Therefore, medial and lateral meniscus tears are two different types of meniscus tears.

CONTENTS

1. Overview and Key Difference
2. What is Medial Meniscus Tear
3. What is Lateral Meniscus Tear
4. Similarities – Medial and Lateral Meniscus Tear
5. Medial vs Lateral Meniscus Tear in Tabular Form
6. Summary – Medial vs Lateral Meniscus Tear

What is Medial Meniscus Tear?

A medial meniscus tear occurs on the inner side of the knee joint and is more common than a lateral meniscus tear. It is an important shock absorber on the inside or medial part of the knee joint. It usually absorbs approximately 50% of the shock of the medial compartment of the knee joint. Therefore, when there is a medial meniscus tear, it is very important to try to repair the tear. If it is not repaired and is trimmed out, there will be an increased load on the medial compartment of the joint, ultimately leading to osteoarthritis. This condition is caused by a sudden motion in which the knee twists while the foot stays planted on the ground. This can frequently occur while playing sports. The symptoms of a medial meniscus tear include pain, swelling, and stiffness that increase gradually over 2 to 3 days, catching or locking, and instability.

A medial meniscus tear can be diagnosed through physical symptoms evaluation and imaging scans such as MRI. Furthermore, medial meniscus tears can be treated through physical therapy, bone marrow elements, platelet-rich plasma (PRP), a large number of inside-out meniscal repair sutures, surgery, and meniscal transplantation. Medial meniscus tears will take a minimum of 6 weeks to heal after the appropriate treatment.

What is Lateral Meniscus Tear?

A lateral meniscus tear occurs on the outside of the knee joint. This type of meniscus tear is less common than medial meniscus tear. The symptoms of this condition may include sudden pain at the time of injury, tender outside surface of the knee when pressing in, knee swelling up, swelling, pain and tenderness along the joint line on the outside of the knee, pain when bending knee or squatting, snapping sound when bending the knee and locking the knee. This type of meniscus tear occurs suddenly from twisting or a traumatic injury. Lateral meniscus tears occur during twisting movements, which causes a direct impact on the knee joint, such as deep squats, or due to degeneration of the cartilage, particularly in older athletes. It can also develop gradually through wear and tear.

Moreover, lateral meniscus tears can be diagnosed through McMurray’s test, Apley’s test, and imaging scans such as MRI. Furthermore, treatment options for lateral meniscus tears may include cold therapy, knee supports/braces, rehabilitation exercises, and lateral meniscus tear surgery. The recovery takes 6 to 8 weeks or up to three months if surgery is needed.

What are the Similarities Between Medial and Lateral Meniscus Tear?

• Medial and lateral meniscus tears are two different types of meniscus tears.
• Both types may have similar symptoms, such as knee swelling, pain, snapping sound when bending, knee locking, etc.
• Both types may lead to osteoarthritis if not managed properly.
• Both types can be diagnosed through physical examination and imaging tests like MRI.
• They can be treated through physical therapy, rehabilitation, and surgery.

What is the Difference Between Medial and Lateral Meniscus Tear?

A medial meniscus tear occurs on the inner side of the knee joint, while a lateral meniscus tear occurs on the outside of the knee joint. Thus, this is the key difference between medial and lateral meniscus. Furthermore, a medial meniscus tear is more common, while a lateral meniscus tear is less common.

The below infographic presents the differences between medial and lateral meniscus in tabular form for side-by-side comparison.

Summary – Medial vs Lateral Meniscus Tear

A meniscus tear occurs when there is an injury to a part of the knee called meniscus. Medial and lateral meniscus tears are two different types of meniscus tears. Both these conditions may cause similar symptoms, such as knee swelling, pain, and locking. However, medial meniscus tear occurs on the inner side of the knee joint, while lateral meniscus tear occurs on the outside of the knee joint. So, this summarizes the difference between medial and lateral meniscus tear.

Reference:

1. “Lateral Meniscus Tear – Symptoms, Causes, Treatment & Rehabilitation.” Sportsinjuryclinic.net.
2. Stanek, Sue, et al. “Medial Meniscus Tear: Knee Specialist: Minnesota.” Robert LaPrade, MD | Minnesota Knee Specialist | Twin Cities, Minneapolis-St.Paul, Edina, Eagan.

Image Courtesy:

1. “Tear of medial meniscus” By Arthroscopist – Own work (CC BY-SA 4.0) via Commons Wikimedia
2. “Lateral meniscus tear anterior horn” By User:Arthroscopist – Own work (CC BY-SA 4.0) via Commons Wikimedia