Transcript Document
P 2
Joint movement – what are joints?
• A joint is a place where two or more bones meet.
• Without joints, our bodies would not be able to move. • Joints, along with the skeleton and muscular system, are responsible for the huge range of movement that the human body can produce.
• There are several different types of joint , each producing different types and amounts of movement.
Different types of joint
There are 3 different types of joint: 1.
Immovable (or fixed) joints 2.
Slightly movable joints 3.
Movable (or synovial) joints
1. Fixed or immovable joints
There are fewer than 10 immovable joints in the body.
They are sometimes called fibrous joints together by tough fibres.
because the bones are held Immovable joints can be found in the skull and pelvis, where several bones have fused together to form a rigid structure.
2. Slightly movable joints
bone cartilage bone
Slightly movable joints are sometimes called cartilaginous joints .
The bones are separated by a cushion of cartilage. The joints between the vertebrae in the spine are cartilaginous joints.
The bones can move a little bit, but ligaments stop them moving too far. This is why we can bend, straighten and rotate through the back, but not too far.
ligaments
3. Freely movable or synovial joints
90% of the joints in the body are synovial joints . They are freely movable .
Synovial joints contain synovial fluid which is retained inside a pocket called the synovial membrane. This lubricates or ‘oils’ the joint.
Synovial fluid
All the moving parts are held together by ligaments .
These are highly mobile joints, like the shoulder and knee.
Synovial membrane Knee
Connective tissues
Connective tissues There are 3 types are vital to the functioning of joints. of connective tissue: Tendons connect muscles to bones.
Ligaments are tough, elastic fibres that link bones to bones.
Cartilage prevents the ends of bones rubbing together at joints. Its slippery surface also helps to lubricate the joint.
Tendons and ligaments
Ligaments are responsible for holding joints together. They prevent bones moving out of position during the stresses of physical activity.
If they are pulled or twisted too far by extreme physical movements, ligaments can tear and the joint may dislocate .
Tendons anchor muscles to bones, allowing the muscles to move the skeleton. Tendons are not very elastic – if they were, then the force produced by muscles would be absorbed instead of creating movement.
Tendons can also be torn if subjected to too much force. Ligaments and tendons are strengthened by training.
Freely movable (synovial) joints
The joint capsule protects and is an outer sleeve that holds the knee together. The synovial membrane lines the capsule and secretes synovial fluid – an oil like liquid which lubricates the joint, allowing it to move freely.
Synovial fluid Cartilage Femur Tibia Synovial membrane Joint capsule
Smooth coverings of cartilage at the ends of the bones stops them rubbing together and provide some shock absorption.
Ligaments hold the bones together and keep them in place.
Task…
Types of joints 1) Give a brief description (Up to 50 words each/also picture examples) of each of the following types of joints, and the movement available at each one - Fixed or fibrous - Slightly moveable or cartilaginous - Synovial or freely moveable 2) Label a Synovial Joint: Copy the picture of the synovial joint from the internet and label/describe it
Types of synovial joints
In
ball and socket joints
, the rounded end of one bone fits inside a cup-shaped ending on another bone.
Ball and socket joints allow movement in all directions and also rotation . The most mobile joints in the body are ball and socket joints.
Examples: Shoulders and hips.
Hip
Types of synovial joints Pivot joints
have a ring of bone that fits over a bone protrusion, around which it can rotate.
These joints only allow rotation .
Atlas
Examples: The joint between the atlas and axis in the neck which allows you to shake your head.
Axis
Types of synovial joints
In
saddle joints
, the ends of the two bones fit together in a special way, allowing movement forwards and backwards right , but not rotation.
and left to Examples: The thumb is the only one.
Hinge joints
– as their name suggests – only allow forwards and backwards movement.
Examples: The knee and elbow.
Elbow
Types of synovial joints Condyloid joints
have an oval shaped bone end which fits into a correspondingly shaped bone end.
They allow forwards , backwards , left and right movement, but not rotation.
Examples: between the metacarpals and phalanges in the hand.
Gliding joints
have two flat faces of bone that slide over one another.
They allow a tiny bit of movement in all directions .
Examples: between the tarsals in the ankle.
Synovial joints –
sporting examples
During the butterfly stroke, the ball and socket joint of the shoulder allows the swimmer’s arm to rotate.
You might head a football using the pivot joint in your neck, which allows your head to rotate.
What type of joint allows a handball player’s fingers to spread apart so that they can control the ball with one hand?
Answer: The condyloid joints between the metacarpals and phalanges.
Movement Patterns…
In order for us to understand sporting movements, we have to be able to label the possible movements available at a joint, using specific terms.
Flexion
When the angle of the joint decreases
Adduction
Movement towards the midline of the body When the angle of the joint increases
Extension Abduction
Movement away from the midline of the body (e.g. A star jump
Circumduction
The limb moves in a Circle. For example this occurs at the shoulder joint during an
‘Overarm bowl in Cricket’
Rotation
The limb moves in a circular motion towards the midline of the body. For example this occurs in a
‘golf swing when driving the ball’
Task…
3/ 4) Find a picture of a player and label all of the 6 major
synovial
joints: - 2 Hinge Joints - 2 Ball and Socket Joints - Gliding Joint - Pivot Joint - Saddle Joint - Condyloid Joints The same picture, use arrows to label the various types of movement pattern occurring at each joint, E.G: Flexion, rotation, plantarflexion, circumduction etc…
.
E.G
Some suggested answers: Left elbow – involves the humerus, radius and ulna. It is a hinge joint. It is extended.
Left wrist – involves the carpals. This is a gliding joint. There is rotation.
Left hand – joint between metacarpals and phalanges. This is a condyloid joint. There is abduction and flexion on the phalanges.
Right hip – involves the pelvis and femur. This is a ball and socket joint. There is abduction.
Knees – involve the femurs, tibias and fibulas. These are hinge joints. There is flexion.
1) Learners need to be able to describe all
three
classifications of
joint
and the amount of movement available at each. 2) Provide a picture and label a
synovial joint
.
3) Provide an example of each
type of Synovial joint
.
3)
Movement
patterns available at each joint.
Movement Patterns:
Flexion/ Extension Adduction/ Abduction Rotation/ Circumduction Supination/ Pronation Plantarflexion/ Dorsiflexion Inversion/ Eversion
Classification of 3 joints:
1. Fixed 2. Slightly Moveable 3. Synovial/Freely Moveable
Types of Joint: