For more information, go to www.arthritisresearchuk.org

What is a joint and how does it work?

Back to Looking after your joints

A joint is where two or more bones meet and is made up of a number of different parts that all work together so that we can bend, stretch, twist and turn easily – but within certain limits. Most of our joints are designed to allow bones to move only in certain directions.

The ends of your bones are covered in a thin layer of cartilage. This cushions the joint and helps to spread the load evenly when you put pressure on it. Its smooth, slippery surface allows your bones to move freely, without friction.

Surrounding the joint is a tough, fibrous sleeve called the capsule, which stops your bones from moving too much. The inner surface of the joint capsule (the synovium) produces a thick fluid that nourishes the cartilage and lubricates the joint.

Within or just outside the joint capsule are ligaments that help to hold the joint together and prevent it dislocating. The bursa helps to reduce friction in the joint.

At either side of the joint, your muscles are attached to the bones by tendons. As your muscles contract, they pull on the bones to make the joint bend, straighten or rotate.

How a joint works

Previous Next
Back to Looking after your joints

Search arthritis information

Exercise and arthritis

Keep moving

Exercise is important for people with arthritis because keeping the joints supple will help to reduce your pain and help you to stay independent. We look at exercises that are particularly useful for people with arthritis.

Arthritis Today magazine

Arthritis Today

Read our online magazine for news on the latest research breakthroughs, treatments and education.

Support Us

Arthritis Research UK softball team cheering

Find out how you can support Arthritis Research UK.

For more information, go to www.arthritisresearchuk.org/arthritis-information or call 0300 790 0400 to order the complete printed booklet.
Arthritis Research UK fund research into the cause, treatment and cure of arthritis. You can support Arthritis Research UK by volunteering, donating or visiting our shops.