Meniscus Injuries

There are two menisci in the knee joint sitting atop the tibia, the medial meniscus and the lateral meniscus. They are made of fibrocartilage that act as cushion and shock absorbers. The medial meniscus is C-shaped with the anterior portion being more narrow and less prone to injury than the posterior portion. In comparison, the lateral meniscus is larger covering more of the tibia, is circular shaped, and is more mobile.

The menisci have a poor blood supply and is avascular with only the outer 10-25% being vascularized. The remaining portion of the meniscus gets its nourishment through synovial fluid.

The anterior fibers of the anterior cruciate ligament (ACL) have attachments to both the medial and lateral menisci. The medial meniscus is attached to the medial collateral ligament (MCL), but the lateral meniscus has no attachments to the lateral collateral ligament (LCL). As a result of these attachments and direction of force on the knee during the injury, meniscus injuries often occur in combination with ligament injuries. Medial meniscus injuries are five times more common than lateral meniscus injuries.

Meniscal injuries commonly occur from a twisting mechanism when the foot is planted in the ground usually with the knee bent. They are usually seen in athletes and represent about 15% of all sports injuries and are more common in males. The meniscus can be torn or completely ruptured. There are six different types of meniscal tears: longitudinal, radial, bucket handle, flap, horizontal cleavage, and degenerative. The degenerative tears are becoming more common in the fourth and fifth decades of life and can occur with little to no trauma and in conjunction with osteoarthritis.

Meniscus injuries will commonly present with knee pain, swelling, the knee locking up and being unable to fully straighten the knee, and sometimes clicking. Medial meniscus injuries are highly likely if the patient has three or more of the following:

·      Pain or tenderness over the medial knee joint line

·      Pain in medial joint line with hyperextension of knee

·      Pain in medial joint line with hyperflexion of knee

·      Pain with external rotation of lower leg when knee is bent 70-90 degrees

·      Weak or decreased muscle mass of quadriceps

Meniscal tears are diagnosed by MRI and conservative care including physical therapy are done initially; some are able to see improvement with PT, but depending on size and location of the tear, surgery may be required. Depending on the location of the meniscal tear, due to the poor blood supply, only tears on the outer portion can be repaired, otherwise, more central tears are cleaned up.

If you are interested in learning more or about treatment options, don’t hesitate to call/text 701-318-4731 or email connectptnd@gmail.com to learn how we can help. Don’t forget to follow on Facebook and Instagram to stay up to date on the happenings at Connect Physical Therapy.

- Alison Fuhrman, PT, DPT, CMPT, OCS