Meniscus Tear

Anatomy

The knee joint is the junction between the femur (thigh) bone and the tibia (shin bone). The end of the femur is referred to as the distal femur and the top of the tibia is referred to as the proximal tibia or tibial plateau.  The kneecap is referred to as the patella. The knee is said to have three compartments – medial (inside), lateral (outside), and patellofemoral (directly behind the patella).  Articular cartilage covers the end of the femur, top of the tibia, and behind the patella and allow the bone to glide easily with one another. The menisci are C-shaped structures that function as shock absorbers between the femur and the tibia. There is one on the inside (medial side) of the knee and one on the outside (lateral side).

What is a Meniscus Tear?

Tears can happen suddenly (acute tears) from a twisting, pivoting, or squatting type motions or over time (degenerative tears). There are many types of tear patterns: bucket handle, flap tears, radial tears, root tears, horizontal tears, or complex tears. Depending on where the tear is affects it’s healing potential. If the tear is in the outer perimeter where the meniscus and capsule (the lining of the joint) meet there is good blood (red zone) supply so good healing potential. The middle zone is the red-white zone is the transition area and has intermediate healing potential while tears in the white zone have no blood supply and poor healing ability.

Symptoms of a Torn Meniscus

• Pain in the medial (inside) or lateral (outside) of the knee depending on location of tear.

• Popping sensation.

• Mechanical symptoms including catching, clicking, pinching sensation.

• Locking of the knee when trying to move it.

• Stiffness of the knee.

Diagnosing a Meniscus Tear

A thorough patient history and physical exam can help to identify patients with a suspected meniscus tear. X-ray images and MRI are useful diagnostic tools to help rule out other injuries and to confirm the diagnosis. 

Treatment for Meniscus Tears 

• Activity modifications.
• Anti-inflammatory medications.
• Physical therapy.
• Injections

• Generally done with minimally invasive techniques using knee arthroscopy.
• Meniscectomy – for meniscus tears with poor healing potential. During a meniscectomy, the torn portion of the meniscus is trimmed out.
• Meniscus repair – the torn portion of the meniscus is reattached to encourage it to heal.