Classifications of Synovial Joints
Ball and Socket Joint
The shoulder and hip joints are classified as ball and socket joint. This joint has the greatest range of movement as it can move in all three planes including forwards and backwards (flexion and extension), side to side (abduction and adduction) as well as turning (rotation). This is due to the ball like head of one bone (e.g. humerus) fitting into a cuplike depression of another bone (e.g. scapula).