This document discusses the classification of bones and joints in the human body. It begins by classifying bones into long, short, flat, and irregular bones based on their shape. It then discusses the three main types of joints - fused joints which are immobile, cartilaginous joints which allow slight movement, and synovial joints which allow free movement. The key synovial joints and their structural features are then outlined, including ball and socket, hinge, pivot, saddle, condyloid, and gliding joints. Ligaments are described as connecting bones and preventing unwanted movement.

1. Exercise and Fitness Lvl 2 Lesson 2 – Joints in Action

2. Lesson 1 Re-cap Progress Test Complete Work sheet 3 on your own

3. Classification of Bones There are 206 bones in the body, these can be classified as: Long Short Flat Irregular Sesamoid

4. Long Bone Such as Femur, tibia, fibula, radius ulna, humerous, Blood Production occurs in the red bone marrow of long bones Long bones provide the body with leverage e.g throwing a cricket ball.

5. Short bones Short bones are found in the wrist and ankle. Short bones are useful for delicate movement where precision is paramount e.g. writing or a surgical operations. Small bones also help dissipate large compressive forces generated during walking and running.

6. Flat Bones Flat can be found in the scapulae, rib cage, sternum and cranium Flat bones offer protection and muscle attachment e.g. the rib cage protects the heart and lungs

7. Irregular Bones Irregular bones can be found in the vertebral column Irregular bones provide muscle attachment points and allow varying movement patterns to occur e.g. The vertebral column

8. Sesamoid Bones Sesamoid bones are small bones formed in tendons e.g. patella ( knee cap). Sesamoid bones provide protection for delicate areas.

9. Joints – 3 types Fused – Immovable e.g. skull Cartiliginous – Slightly movable e.g. between vertebral column Synovial – Freely movable e.g hip & knee

10. Key Joint Facts Formed wherever two or more bones meet The skeleton would be ‘ fixed ’ without them Bones that form a joint ‘fit well’, if irregularities exist they are evened out by extra layers of cartilage The above are called ‘ menisci ’ if they only partly divide a joint cavity If they fully divide the joint cavity this cartilage is called a disc Most joints are held together by ligaments

11. Ligaments

12. Fixed or Fibrous Joints Has no movement Tough fibrous tissue lies between the ends of the bones The ends are ‘ dovetailed ’ together There is no joint cavity (space between the bones’ E.g. sutures in the skull

13. Example of fixed Joint - Skull

14. Cartilagenous Joints Allows some slight movement Ends of the bones are covered in articular cartilage Ends are separated by pads of white fibro cartilage Compression of these pads permits slight movement These pads also act as ‘ shock absorbers ’ Eg: intervertebral discs of the spinal column

15. Synovial Joints Distinguishing features; Ends are covered in articular cartilage Inners surface of joint capsules is lined with a thin synovial membrane that produces synovial fluid Freely movable joints Characterised by the presence of a joint capsule and cavity (space between bones) Range of movement can vary due to the shape of the bony surfaces forming the joint The synovial fluid acts as a lubricant for the joint, provides nutrients E.G. knee

16. Synovial Joint Structure

17. Key Synovial Joints Ball & Socket Shoulder, Hip Pivot Neck Condyloid Wrist Saddle Thumb Hinge Elbow Gliding Carpels

18. Ball & Socket Movement in all directions Rotation Adduction / abduction Flexion / extension Articulating bones; Head of femur / pelvis, humerous & scapula E.g. Hips & shoulders Sporting eg; Clearing a hurdle / overhead clear in badminton

19. Pivot & Gliding Pivot Rotation Articulating bones; C1 & C2 vertebrae Neck (C1 vertebrae) Turning head to view situations Gliding Movements across flat surfaces of bones Articulating bones; Clavicle / intercarpal/ intertarsal Bending back, landing; feet absorbing impact- flexion / extension of foot

20. Condyloid Sometimes referred to as Ellipsoid Reduced ball & socket configuration Articulating bones; Radio carpal joint (radius / ulna / carpals) Wrist Flicking of the racket in badmington

21. Saddle & Hinge Saddle All movements but no rotation Articulating bones Carpal & metacarpals Base of thumb Gripping of sporting equipment Hinge Flexion / extension Articulating bones; Humerus / radius & ulna Elbow Hitting a backhand

22. Location of Synovial Joints

23. Ligaments

24. Conclusion Ligaments Connects bone to bone, are strong, inelastic, dense, fibrous tissue that links boney segments. Prevent any unwanted movement & restricts movement in certain directions Joints are formed wherever two or more bones meet, the skeleton would be ‘ fixed ’ without them. Most joints are held together by ligaments Joints can be classified in 2 ways; Functional & Structural The amount of movement available at the joint determines their classification Fixed or fibrous Immovable Cartilagenous Slightly moveable Synovial Freely movable The main synovial joints are; ball & socket, hinge, saddle, pivot, condyloid, gliding

25. Now complete…. Now complete worksheet 4