1. Unit 1: Types of Joints

2. Learning Objectives
All students will be able to describe what joints are
All students will be able to classify joints into one of three categories
All students will be able to identify the six different types of synovial joints
Some students will be able to explain why different classifications of joints allow different ranges of movement

3. 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.
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4. Different types of joint
There are 3 different types of joint:
1. Immovable (or fixed) joints
2. Slightly movable joints
Reference to skeletal structures could be enhanced by using a skeleton or skeletal models if available. Use this presentation to remind students of the names of a range of bones. Students must be confident in naming the bones of the skeleton and their position/ location in the body. Without this understanding they will struggle to identify the bones that form joints.
3. Movable (or synovial) joints

5. 1. Fixed or immovable joints
There are fewer than 10 immovable joints in the body.
They are sometimes called fibrous joints because the bones are held together by tough fibres.
Where can these be found in the body?
Immovable joints can be found in the skull and pelvis, where several bones have fused together to form a rigid structure.
Fixed or immoveable joints such as those of the flat bones of the skull allow very slight movement – ask students why they should allow a little movement. Movement is necessary for expansion of the soft tissues of the brain and to absorb some of the force of impacts – if joints were completely fixed they might crack with an impact such as a blow on the head.

6. 2. Slightly movable joints
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.
bone
cartilage
Discuss with students the structure of the spinal column and why slightly moveable joints are the most suitable type of joint for the cervical, thoracic and lumbar spine areas. Ask them why the sacrum and coccyx areas of the spine are fixed joints? Answer: for attachment of lower back muscles (Sacrum) and balance (coccyx).
bone
ligaments

7. 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.
All the moving parts are held together by ligaments.
These are highly mobile joints, like the shoulder and knee.
Synovial fluid
Synovial joints offer a wide range of sporting movement.
Synovial membrane

8. Different types of joint

9. Freely movable (synovial) joints
The joint capsule is an outer sleeve that protects and holds the knee together.
The synovial membrane lines the capsule and secretes synovial fluid – a liquid which lubricates the joint, allowing it to move freely.
Synovial fluid
Femur
Synovial membrane
Tibia
Cartilage
Students should be able to recognise the key structures of the knee and their function.
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.

10. Synovial Joints There are six different types of synovial joints:
Please use this website very informative
Hinge Joint
Ball and socket joint
Ellipsoid (condyloid joint)
Gliding Joint
Pivot Joint
Saddle joint

11. Activity 1
Working in pairs. Provide a description of the six different joint of the skeleton, providing examples.

12. Ball and Socket Joints
In ball and socket joints, the rounded end of one bone fits inside a cup-shaped ending on another bone.
Hip
Describe ball and socket joints at the hip and shoulder. Discuss the movements possible at these joints. How do they help during sport?
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.

13. Pivot 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

14. Saddle Joints
In saddle joints, the ends of the two bones fit together in a special way, allowing movement forwards and backwards and left to right, but not rotation.
Examples: The thumb is the only one.

15. Ellipsoid (Condyloid) 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.

16. Gliding Joints
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.

17. Hinge Joints
Elbow
Hinge joints – as their name suggests – only allow forwards and backwards movement.
Examples: The knee and elbow.

18. Types of synovial joints

19. Activity 2
In the same pairs you were in earlier: You need to provide a sporting example for the use of each joint. For example: During the butterfly stroke, the ball and socket joint of the shoulder allows the swimmer’s arm to rotate. What would happen to the performance if there was another type of synovial joint present? (You might have to present back to the rest of the class)

20. Why do some joints allow for different ranges of movement?
Class Discussion
Why do some joints allow for different ranges of movement?

21. Joint movement – how do we move?

22. What other movements are we missing?

23. Working with a partner:
Take it in turns to demonstrate a simple sporting movement, for example performing a biceps curl or taking a step forward.
Together, analyze the movement and decide what types of movement are occurring at each joint.
Now take it in turns to name a joint. Ask your partner to demonstrate and name all of the movements possible at that joint.
For example, the hinge joint at the elbow shows flexion, extension and slight rotation.