Lec 2 Joints of the human body and articulation.pptx

Anatomy

1. Joints

2. Key points 01 Joints: Structural and functional classification 03 Types of synovial joints 02 Structure of a typical synovial joint

3. JOINTS Defined: any place where two bones come together General Function of Joints: Hold the skeleton together Allow for increased mobility and flexibility of skeleton

4. Classification of joints Joints can be classified based on: Function (what kind of movement they allow) Structure (what material is found in the joint and if is there a joint cavity present ).

5. Functional Classification Synarthroses – joints that have NO movement. Examples: sutures of the skull, gomphoses- teeth Amphiarthroses – partially movable joints. Examples: intervertebral disc and pubic symphysis Diarthroses – freely movable joints. The most common type of functional joint in the body. Examples: knee joint, shoulder joint, finger joints, ankle and wrist joints, etc .

6. Structural Classification Fibrous joints (synarthroses): adjacent bones are joined by collagen fibers. 3 kinds: sutures , gomphoses and syndesmoses. Cartilaginous joints (amphiarthroses): two bones are joined by cartilage . 2 kinds: synchondroses , and symphyses. Synovial joints (Diarthroses): freely movable and most common joint in the body .

7. Joint mobility comparison Mobility decreases, stability increases and vice versa.

8. Fibrous joints (synarthroses):

9. Cartilaginous joints (amphiarthroses)

10. Synovial Joints (diarthroses ) This type of joint is defined by the presence of a joint cavity filled with fluid. Most joints of the body fall into this class. Examples : knee joint, elbow joint, shoulder and hip joints and the phalanges of hands and feet, etc .

11. Structures in a Synovial Joint Articular capsule – external and internal Joint/synovial cavity – filled with synovial fluid Articular cartilage – Hyaline cartilage Synovial fluid – viscous/ clear colorless fluid Ligaments – give the joint reinforcement and strength Nerves – provide feelings of pain and stretch Vessels - provide nutrients to joint

12. Typical Synovial Joint

13. Additional joint structures Ligaments- join bones to bones Consists of dense regular connective tissue. Tendons- join muscles to bone Consists of dense regular connective tissue. Bursae- fibrous sac lined with synovial membrane and containing synovial fluid Occurs between bones and tendons or muscles Acts to decrease friction during movement

14. Accessory joint structures Fatty pads - cushioning Menisci – tough fibrocartilage Bursae -flattened fibrous sac lined by synovial membrane. Tendon sheaths -fibrous tissue connecting a muscle to a bone

15. Types of Synovial Joints Plane (gliding) Joints Hinge Joints Pivot Joints Condyloid Joints Saddle Joints Ball and Socket Joints

16. Types of Synovial Joints