Skeletal system - OCRFour important synovial joints
The skeleton is the central structure of the body and is made up of bones, joints and cartilage. The skeleton provides the framework for muscles and gives the body its defined human shape.
Four important synovial joints used in most sporting actions are the elbow and shoulder joints in the arm, and the knee and hip joints in the leg.
The elbow and knee joints are both hinge joints. A hinge joint is a type of synovial joint that works like the hinge on a door, allowing bending and straightening only.
The shoulder and hip joints are both ball and socket joints. A ball and socket joint is a type of synovial joint that allows movement in almost every direction. A ball and socket joint is made up of a round end of one bone that fits into a small cup-like area of another bone.
Elbow joint
Hinge joint.
Articulating bones are humerus, radius and ulna.
Allows bending (flexion) and straightening (extension).
Muscles which move the elbow are biceps and triceps.
Knee joint
Hinge joint.
Articulating bones are femur and tibia (the patella is not classed as part of the joint, nor is the fibula).
Allows bending (flexion) and straightening (extension).
Muscles which move the knee are quadriceps and hamstrings.
Hip joint
Ball and socket joint
Articulating bones are pelvis and femur (head of femur is 'ball' and cup in pelvis is 'socket')
Allows a large range of movement in all directions
Many muscles are used to move the hip joint, including the gluteals
Shoulder joint
Ball and socket joint.
Articulating bones are humerus and scapula (the clavicle is not part of the shoulder joint).
Allows a great range of movement in all directions.
Many muscles are used to move the shoulder joint, including the deltoid, trapezius and latissimus dorsi.