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Physical Education

The skeleton, bones and joints

Joints and their function

A joint is where two or more bones meet. The hip is a typical synovial joint [Synovial joint: A freely moveable joint. Examples include the hip, shoulder, elbow and knee joints. ]. All synovial joints have the same components:

Synovial joints

  • Cartilage reduces friction. Acts as a shock absorber.
  • Synovial fluid lubricates the joint.
  • Synovial membrane produces synovial fluid.
  • Tendon joins muscle to bone enabling movement.
  • Ligament joins bone to bone, stabilising the joint.

Limbs move in different directions using joint actions. Use the following terms to describe the movements:

Limb movements

MovementDescription
AbductionMovement away from the mid-line of the body
AdductionMovement towards the mid-line of the body
Extension Straightening limbs at a joint
FlexionBending the limbs at a joint.
RotationA circular movement around a fixed point

Back to Applied anatomy and physiology index

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