Tanglin PE Theory

1. Secondary Two
Topic: Bones and Joints
Sub Topic: Joints and
Movements

2. • Students will be able to:
• understand what is a joint;
• name the 3 types of joints;
• name the 2 main causes of joint injuries.

3. • Fixed / Immoveable joints
• Slightly moveable joints
• Freely moveable joints
• Ligaments
• Joint cavity
• Synovial membrane

4. • One conversation
• No sleeping
• Putting of palm on whiteboard
• Class too noisy and need to quieten
down

5. WHAT IS JOINTS?

6. Do you remember…
 How many bones do we have in our body?
◦ 206 bones

7. Between connecting bones…
 The bones connected together by
ligaments (strong fibres)
 The area where two or more bones
meet is called a joint
Ligament
Joint

8. Types of Joints
 There are 3 types of joints
◦ Fixed / Immoveable joints
◦ Slightly moveable joints
◦ Freely moveable joints

9. FIXED / IMMOVEABLE
JOINTS
Types of joints

10. Fixed or Immoveable Joints
 Also known as fibrous joints
 Joints with very tough fibre to prevent
movement between the connecting bones
 Can you think of any immoveable joints?
Fixed joints

11. Fixed or Immoveable Joints
 Why would we want immoveable
joints?
◦ Eg. Skull (cranium)
◦ Babies are borned with the plates in the
cranium not joined together
◦ Facilitates birth / delivery
◦ The plates are joined after birth to provide
protection for the brain

12. SLIGHTLY MOVEABLE
JOINTS
Types of joints

13. Slightly Moveable Joints
 Also known as cartilaginous joints
 Allow very small amount of movement
 Joints are connected by cartilage
 Can you name some slightly
moveable joints?

14. Slightly Moveable Joints
Cartilage pad
Joint between
each vertebrae
Joint between
ribs and
sternum

15. Slightly Moveable Joints
 The connecting cartilage acts as a
cushioning layer (shock absorber)
between the bones
 The bones serves largely as protective
layer for important parts of the body
 But allows slight movement to
facilitate day-to-day actions
◦ Eg. Bending of back, breathing

16. FREELY MOVEABLE
JOINTS
Types of joints

17. Freely Moveable Joints
 More commonly known as synovial
joints
 Allow a large degree of movement
 Exist 4 different types which allow
different kind of movement
◦ Ball and socket
◦ Hinge
◦ Pivot
◦ Gliding
Covering in next lesson

18. Freely Moveable Joints
 A typical freely moveable joint looks
like this:

19. Freely Moveable Joints
 Parts of the typical moveable joint
include:

20. Freely Moveable Joints
 The functions of the various parts of a freely
moveable joint are as follow:

21. Freely Moveable Joints
 Can you name 5 examples?

22. Trivia…
◦ Bones pulled further
apart
◦ Expansion of the
synovial membrane
◦ Results in temporary
expansion of synovial
cavity
◦ Increase volume =
decrease pressure
◦ Cavitation (formation of
air bubbles)
◦ When pressure over-
reduced, the bubbles
burst, thus the “CRACK”
sound
◦ Not medically proven to
 What happens when you crack your knuckles
(joints at the finger)?

23. JOINT INJURIES

24. Joint Injuries
 Joint injuries come in few forms:
◦ Bone injuries
 Wear and tear
 Impact
◦ Ligament injuries
 Most common joint injuries happened
on
◦ Knee
◦ Ankle

25. Our Knee
 Three bone meet at the knee joint
◦ Femur (thigh bone)
◦ Tibia (shin bone)
◦ Patella (knee cap)

26. Our Knee
 Other components of knee joint
◦ Articular cartilage – Protects end part of femur
and tibia.
◦ Meniscus – Additional cartilage material between
femur and tibia for shock absorption
◦ Ligaments – Strong fibres holding femur and tibia
together

27. Knee Injuries
 Articular cartilage wear and tear at the
knee

28. Knee Injuries
 Meniscus tear – Happens when
there’s sudden movement of twisting,
pivoting, or being tackled

29. Knee Injuries
 Wear and tear of cartilage due to
heavy weight

30. Other Joint Injuries
 More joint and bone related injuries
will be covered in the later part of the
term

31. Lets Recap
• Fixed / Immoveable joints
• Slightly moveable joints
• Freely moveable joints
• Ligaments
• Joint cavity
• Synovial membrane