Synovial joints are the most common type of joint.

They allow a great degree of movement, for example at the knee, shoulder, elbow and wrist. (The illustration shows the knee - use the controls to see more detail.)

A typical synovial joint is enclosed in a fibrous capsule and supported by strong ligaments.

The capsule is lined with a synovial membrane that secretes fluid into the joint space to lubricate the joint.

The surfaces of the bones at the joint are lined with smooth, hard-wearing articular cartilage that minimises wear and tear on the bones.

There are several types of synovial joint which we’ll now look at in more detail.