Lateral meniscus

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Lateral meniscus
Blausen 0597 KneeAnatomy Side.png
Knee from the side, with lateral meniscus simply labeled as "meniscus".
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Head of right tibia seen from above, showing menisci and attachments of ligaments.
Details
Identifiers
Latin meniscus lateralis
TA98 A03.6.08.002
TA2 1885
FMA 44631
Anatomical terminology

The lateral meniscus (external semilunar fibrocartilage) is a fibrocartilaginous band that spans the lateral side of the interior of the knee joint. It is one of two menisci of the knee, the other being the medial meniscus. It is nearly circular and covers a larger portion of the articular surface than the medial. It can occasionally be injured or torn by twisting the knee or applying direct force, as seen in contact sports.

Contents

Structure

The lateral meniscus is grooved laterally for the tendon of the popliteus, which separates it from the fibular collateral ligament.

Its anterior end is attached in front of the intercondyloid eminence of the tibia, lateral to, and behind, the anterior cruciate ligament, with which it blends; the posterior end is attached behind the intercondyloid eminence of the tibia and in front of the posterior end of the medial meniscus.

The anterior attachment of the lateral meniscus is twisted on itself so that its free margin looks backward and upward, its anterior end resting on a sloping shelf of bone on the front of the lateral process of the intercondyloid eminence.

Close to its posterior attachment it sends off a strong fasciculus, the ligament of Wrisberg, which passes upward and medialward, to be inserted into the medial condyle of the femur, immediately behind the attachment of the posterior cruciate ligament.

The lateral meniscus gives off from its anterior convex margin a fasciculus which forms the transverse ligament.

Variation

Occasionally a small fasciculus passes forward to be inserted into the lateral part of the anterior cruciate ligament.

Clinical significance

The lateral meniscus is less likely to be injured or torn than the medial meniscus. Diagnosis of lateral meniscus tear is done with McMurray's test. If a tear is detected, treatment depends on the type and size of the tear. Small tears can be treated conservatively, with rest, ice, and pain medications until the pain is under control, then exercise may be started with gradually increasing intensity, to improve range of motion and decrease swelling. More severe tears of the lateral meniscus require surgical repair or removal, which can often be done arthroscopically. Swelling and stiffness of the knee can occur when you have a torn lateral meniscus.

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See also

Related Research Articles

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<span class="mw-page-title-main">Posterior cruciate ligament</span> One of four major ligaments of the knee

The posterior cruciate ligament (PCL) is a ligament in each knee of humans and various other animals. It works as a counterpart to the anterior cruciate ligament (ACL). It connects the posterior intercondylar area of the tibia to the medial condyle of the femur. This configuration allows the PCL to resist forces pushing the tibia posteriorly relative to the femur.

<span class="mw-page-title-main">Anterior cruciate ligament</span> Type of cruciate ligament in the human knee

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<span class="mw-page-title-main">Medial meniscus</span> Cartilage formation in the human knee

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<span class="mw-page-title-main">Articular capsule of the knee joint</span>

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<span class="mw-page-title-main">Coronary ligament of the knee</span>

The coronary ligaments of the knee are portions of the joint capsule which connect the inferior edges of the fibrocartilaginous menisci to the periphery of the tibial plateaus.

<span class="mw-page-title-main">Transverse ligament of knee</span>

The transverse or [anterior] meniscomeniscal ligament is a ligament in the knee joint that connects the anterior convex margin of the lateral meniscus to the anterior end of the medial meniscus.

Posterolateral corner injuries of the knee are injuries to a complex area formed by the interaction of multiple structures. Injuries to the posterolateral corner can be debilitating to the person and require recognition and treatment to avoid long term consequences. Injuries to the PLC often occur in combination with other ligamentous injuries to the knee; most commonly the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). As with any injury, an understanding of the anatomy and functional interactions of the posterolateral corner is important to diagnosing and treating the injury.

<span class="mw-page-title-main">Medial knee injuries</span> Medical condition

Medial knee injuries are the most common type of knee injury. The medial ligament complex of the knee consists of:

<span class="mw-page-title-main">Intercondylar area</span>

The intercondylar area is the separation between the medial and lateral condyle on the upper extremity of the tibia. The anterior and posterior cruciate ligaments and the menisci attach to the intercondylar area.

References

PD-icon.svgThis article incorporates text in the public domain from page 343 of the 20th edition of Gray's Anatomy (1918)