how how many joints are there in our body with explanation and example
Answers
Types of Joints
- Ball and socket joints ⟹ These are found in hip area.
- Hinge Joints ⟹ These are found in elbows and knees.
- Pivot Joints ⟹ These are only found in the skull.
- Gliding Joints ⟹ These are found in the wrist areas.
Types of Synovial Joints
Synovial joints are further classified into six different categories on the basis of the shape and structure of the joint.
Planar Joints
Planar joints have bones with articulating surfaces that are flat or slightly curved faces. These joints allow for gliding movements, and so the joints are sometimes referred to as gliding joints.
Planar joints are found in the carpal bones in the hand and the tarsal bones of the foot, as well as between vertebrae.
Hinge Joints
In hinge joints, the slightly rounded end of one bone fits into the slightly hollow end of the other bone. In this way, one bone moves while the other remains stationary, like the hinge of a door. The elbow is an example of a hinge joint.
Pivot Joints
Pivot joints consist of the rounded end of one bone fitting into a ring formed by the other bone. This structure allows rotational movement, as the rounded bone moves around its own axis. An example of a pivot joint is the joint of the first and second vertebrae of the neck that allows the head to move back and forth.
Condyloid Joints
Condyloid joints consist of an oval-shaped end of one bone fitting into a similarly oval-shaped hollow of another bone (Figure 5). This is also sometimes called an ellipsoidal joint. This type of joint allows angular movement along two axes, as seen in the joints of the wrist and fingers, which can move both side to side and up and down.
Saddle Joints
Saddle joints are so named because the ends of each bone resemble a saddle, with concave and convex portions that fit together. Saddle joints allow angular movements similar to condyloid joints but with a greater range of motion. An example of a saddle joint is the thumb joint.
Ball-and-Socket Joints
Ball-and-socket joints possess a rounded, ball-like end of one bone fitting into a cuplike socket of another bone. This organization allows the greatest range of motion, as all movement types are possible in all directions. Examples of ball-and-socket joints are the shoulder and hip joints.