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Normal Skeleton

The skeleton is important for posture, movement and protection of vital structures.

The hip and shoulder are 'ball and socket' joints that optimise movement. The knee and elbow are hinge joints. The ankle and wrist joints allow movement in several different directions. The spine comprises different sections - cervical, thoracic, lumbar and sacrum.

The normal joint - A joint is where two or more bones meet. Synovial joints are joints that have a synovial membrane. All synovial joints have the same components:

The components of normal joints and their function 
Synovial fluid lubricates the joint
Cartilage reduces friction and is a shock absorber
Synovial lining produces synovial fluid (An effusion occurs with inflammation)
Tendon joins muscle to bone enabling movement and joint stability
Ligament joins bone to bone, stabilising the joint


More information is given - please see Describing Bone, Joint and Muscle - this includes Surface Anatomy, Joint movement and the Skeleton.

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