Joints

PE to 16 p 20-23

3 Types of Joints

These can't move at all - movement would be a severe disadvantage

eg bones of the cranium + the joint between the pelvis and the vertebral column.

Here movement is needed but only to a certain point

eg the vertebral column.

They are held together by strong white cords called ligaments and are separated by cartilage. This stops the bones from knocking together.

These occur in most places in the bodywhere a resonable degree of movement occurs

They are surrounded by a CAPSULE, the internal lining of which secretes SYNOVIAL FLUID to LUBRICATE the joint. (see below)

Allow a full a range of movement eg the hip and shoulder joints

Movement in one plain: flexion and extension eg the elbow and knee joints

Allows rotation eg Atlas and Axis in the neck

Tight fitting surfaces move side to side, forwards and back eg Thumb (the only one)

Tight fitting surfaces move side to side, forwards and back eg Wrist

PE to 16 p 24,25

A joint straightened or EXTENDED in its natural position to its full extent.

eg standing

A movement AWAY from the central line of the body

eg a back-hand in tennis

A movement TOWARDS the central line of the body

eg fore-hand in tennis

A joint bent or FLEXED so that one of the bones of the joints moves towards the other

eg a bicep curl

A TURNING movement around a central point or pivot

eg a golf swing