1. Cartilage is an important structural component of the body. It is a firm tissue but is softer and much more flexible than bone.

Cartilage is a connective tissue found in many areas of the body including:

• Joints between bones e.g. the elbows, knees and ankles

• Ends of the ribs

• Between the vertebrae in the spine

• Ears and nose

• Bronchial tubes (支气管) or airways

Due to the lack of blood vessels, cartilage grows and repairs more slowly than other tissues.

2. Cartilage is categorized into three types which include:

Hyaline cartilage

This is a low-friction, wear-resistant tissue present within joints that is designed to bear and distribute weight. It is a strong, rubbery, flexible tissue but has a poor regenerative capacity.

Elastic cartilage

Elastic cartilage is more flexible that hyaline cartilage and is present in the ear, larynx and epiglottis.

Fibrocartilage

Fibrocartilage is a tough and inflexible form of cartilage found in the knee and between vertebrae.

Articular cartilage

Articular cartilage is the hyaline cartilage that lies on the surface of bones. This cartilage is often described in terms of four zones between the articular surface and the subchondral bone which include:

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