Meniscus vs. Cartilage Tear of the Knee

It is common to hear the terms "meniscus tear" and "cartilage tear" used interchangeably. This has created some confusion about the difference between the two terms.

Cartilage is a type of connective tissue. Our bodies make different types of cartilage for different purposes.

A meniscus is a cushion in the knee joint. It is made up of one of the two types of cartilage found in the knee. The other is called articular cartilage. Tears can occur in both types.

This article looks at the difference between a meniscus tear and a cartilage tear. It also discusses the types of cartilage injury and some possible treatments.

Knee Cartilage Types

The knee joint contains two types of cartilage: articular and meniscus.

Articular cartilage forms the smooth layer of the joint that covers the ends of bones. A layer of this cartilage covers the end of the thigh bone, the top of the shin bone, and the back of the kneecap.

The meniscus is a different type of cartilage. This type acts as a shock absorber between bones. The meniscus is not attached to the bone like articular cartilage. Instead, it sits between the bone ends to cushion the joint.

The purpose of both types of cartilage is to protect the knee joint by keeping the bones from rubbing together. They also help the knee move smoothly.

Types of Cartilage Injury

Knee cartilage can be damaged in a few different ways, including:

• Traumatic injury
• Degenerative arthritis
• Chronic overuse

Depending on the type of injury, different types of cartilage may be damaged. When cartilage is damaged, it is often described as a tear of the cartilage.

Meniscus tears are common knee injuries, but tears can also happen in the articular cartilage.

Words that describe an injury to the articular cartilage include:

• Fissuring: A fissure is a crack in a layer of cartilage. This causes a separation in the layer. Sometimes this causes no symptoms. In other cases it can cause a "catching" sensation if it blocks movement of the knee joint.
• Thinning: Cartilage thinning can occur after an injury. It may also be an early sign of arthritis in the knee. Thin cartilage may not appear as smooth as normal cartilage. It also may not glide as easily.
• Flaps: Flaps in the articular cartilage occur when part of the cartilage separates from the bone and can be lifted from its normal position. This can also lead to catching sensations with knee movement.
• Defects: Cartilage defects can lead to exposed bone within the joint. This can occur after traumatic injuries. It can also occur as a result of knee arthritis.

Treatment of Cartilage Injury

Meniscus tears usually require treatment. The good news is that not all meniscus tears need surgery. Some meniscus tears, though, do respond best to surgical intervention.

Damage to both types of cartilage is often the result of long-term degeneration and arthritis. This type of damage may cause serious symptoms such as pain and disability. Still, in many cases, surgery is no better than nonsurgical treatment.

Nonsurgical treatment of meniscus tears may include:

• Rest
• Icing the knee and keeping it elevated
• Anti-inflammatory medications
• Physical therapy
  

Always see a doctor if you have a knee injury. A doctor can help determine if surgery is necessary.

Summary

There are two types of cartilage in the knee. Tears can happen in both articular cartilage and a meniscus. 

Meniscus tears are common. When you hear someone refer to a cartilage tear, they are usually talking about the meniscus.

Tears can be caused by injury, arthritis, or chronic overuse. Not all tears require surgery, but many do.