Cartilage damage is a relatively common type of injury. The majority of cases involve the knee joint. Symptoms of cartilage damage include:
- swelling
- joint pain
- stiffness
Cartilage
Cartilage is a tough, flexible tissue that is found throughout the body. Cartilage serves two main functions:
- it acts as a shock absorber
- it acts as a mould
Cartilage covers the surface of joints, enabling bones to slide over one another while reducing friction and preventing any damage. It helps to support your weight when you move, bend, stretch and run.
The tough, flexible cartilage tissue is ideal for creating specially shaped and curved body parts that would otherwise have no support from the bones. For example, most of the nose and the outside of the ears are made up of cartilage tissue.
Unlike other types of tissue, cartilage does not have its own blood supply. Blood cells help to repair damaged tissue, therefore damaged cartilage does not heal as quickly as damaged skin or muscles.
Types of cartilage
There are three types of cartilage. They are:
- elastic cartilage
- fibrocartilage
- hyaline cartilage
These are described in more detail below.
Elastic cartilage
Elastic cartilage is the most springy and supple type of cartilage. This type of cartilage makes up the outside of the ears, some of the nose, and the epiglottis (the flap of tissue at the back of the throat, which prevents food going down into your airways).
Fibrocartilage
Fibrocartilage is the toughest type of cartilage and it can withstand a great deal of weight. It is found between the discs (vertebrae) of the spine and between the bones of the hips and pelvis.
Hyaline cartilage
Hyaline cartilage, also known as articular cartilage, is both springy and tough. It is found between the ribs, around the windpipe (trachea) and between the joints.
Types of cartilage damage
All three types of cartilage can be damaged. For example, a blow to your ear can damage the elastic cartilage, making your ear look deformed. This condition is often seen in rugby players and is known as ‘cauliflower ear’.
The fibrocartilage between the discs in your back can also become damaged, resulting in a slipped disc. See the Health A-Z topic about Slipped disc for more information.
One of the most common and potentially serious types of cartilage damage is damage to the articular cartilage between a joint (usually the knee joint). The damage can result in pain, swelling and some loss of mobility.
There are two main ways that the articular cartilage can be damaged:
- as a result of a sudden accidental injury to the cartilage – for example, falling badly and landing on your knees
- long-term damage that occurs due to a process of ‘wear and tear’ – this type of long-term cartilage damage to the joints is known as osteoarthritis.
The rest of this article focuses on articular cartilage damage.
How common is cartilage damage?
It is hard to estimate exactly how common cartilage damage is because many people with mild cartilage damage do not seek medical help. However, cartilage damage is thought to be quite common.
Every year in the UK, around 10,000 people have cartilage damage that is serious enough to require treatment.
Cases of accidental cartilage damage are most common in people under 35 years old. This is because this age group are more likely to take part in sporting activities where there is a higher risk of injury than older people.
Cartilage damage that is associated with osteoarthritis is more common in adults who are 50 years old or over. It is also more common in women than in men.
Outlook
The outlook for most cases of accidental cartilage damage is moderate to good, although it can take a considerable amount of time for the cartilage to regain its normal function. This is because, unlike other types of tissue, cartilage does not have its own blood supply, which means that any damage takes longer to heal.
Treatment options for accidental cartilage damage include supportive devices, such as a leg brace, and a range of different surgical techniques.
The outlook for cartilage damage that is associated with osteoarthritis is less favourable. This is because there is currently no cure for osteoarthritis. In the most serious cases, the entire joint may need to be replaced with an artificial joint, such as a knee replacement or hip replacement.
