What is the meniscus?

There are two menisci in your knee; each rests between the thigh bone (femur) and shin bone (tibia). The menisci are made of tough cartilage and conform to the surfaces of the bones upon which they rest. One meniscus is on the inside of your knee; the medial meniscus. The other meniscus rests on the outside of your knee, the lateral meniscus.

The meniscus is often referred to as the “cartilage” in the knee.  Both the meniscus and the covering of the bone within the joint are made of cartilage.  Articular cartilage is the covering that caps the ends of the bone and the wedges of cartilage between the knee are the meniscus.

When people talk about a cartilage tear, they are talking about a meniscus tear. When people talk about arthritis and wear of cartilage they are talking most often about the articular cartilage on the ends of the bone.

 

What is the role of the meniscus?

The role of the meniscus is to evenly distribute your body weight across the knee joint.  If the meniscus is not present your bodyweight would be unevenly distributed through the bones in your legs, the femur (thigh) and tibia (shin).  This causes excessive forces to be applied to specific areas of bone and will lead to early arthritis of the knee joint.

 

How does a meniscus tear?

There are 2 common causes of meniscal tears, degenerative which is generally seen in older patients, where the meniscus becomes more brittle and traumatic, often seen in the athlete who reports twisting on a bent knee with the foot fixed on the ground.  The meniscus may tear in isolation or may also see injury to the ACL and/or MCL at the same time.  This can often be seen in skiing injuries or in soccer players where the player has been hit on the outside of the knee.

 

Symptoms of a Meniscal Tear?

Individuals who experience a meniscus tear usually report pain and swelling as their primary symptoms.  They may also complain of the joint locking or the inability to completely straighten the knee due to a piece of the torn meniscus impinging the knee joint.

 

How is a meniscal tear diagnosed?

The physiotherapist can take a detailed history of the events leading up to the knee pain and perform a physical examination including some specific tests that can determine if damage to the meniscus has occurred.  An MRI scan may be required to confirm  a tear in the meniscus.

 

Do I need surgery if I have a meniscal tear?

Treatment of a meniscal tear can be conservative and involve physiotherapy to manage the symptoms and maintain strength around the knee joint until symptoms settle.  However the type of tear often depends on whether surgery is required.    The meniscus is nourished by small bold vessels that are present around the outer part of the meniscus.  A large area in the centre has no blood supply (avascular).  The avascular area tends not to heal without the essential nutrients supplied by the blood vessels.

The tears to this area often require surgery, which involves an arthroscopy (small camera) being inserted into the knee and the torn area is trimmed.  Physiotherapy post arthroscopy is beneficial to aid return to sport.

If you are experiencing any of the above symptoms, call  the physio at Back2Balance Physiotherapy to make an appointment on 3352 5311 for an assessment and advice.