21. Different types of joint 1. Immovable (or fixed) joints 3. Movable (or synovial) joints 2. Slightly movable joints
22. 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. Immovable joints can be found in the skull and pelvis, where several bones have fused together to form a rigid structure.
23. 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 ligaments cartilage bone
24. 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 Knee Synovial membrane
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.
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.
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).
Synovial joints offer a wide range of sporting movement.