Question

Name the kind of joint found in our knee and at the elbow.

Answer 1

Hint: The area where two or more bones are connected or attached with the help of fibrous connective tissue and cartilage to permit body parts to move is known as joint.

Complete answer:
According to the type of motion, Joints are grouped into:
1. Ball-and-socket joint, hinge joint and condyloid joint- These joints permit all forms of angular movement except the axial rotation.
2. Pivot joint, gliding joint, and saddle joint- these joints can move in only four ways. At a gliding joint one bony surface glides on another, without angular or rotatory movement.

The kind of joint found in our knee and at the elbow is a hinged joint (hinge joint). The working of this joint is similar to that of the hinge of a window or a door. This is a type of synovial joint that permits movement in one direction only. Usually, this is achieved by a concave surface articulating with a corresponding convex surface. At the joint, protective cartilage that covers the bones, and a thick gel called synovial fluid is present that lubricates them, this is for allowing them to move without rubbing against one another.

Note:
- Angular movement at joint means a movement that occurs only between long bones, which helps in increasing or decreasing the angle between the bones.
- The circumduction movement of joints is composed of the head of a bone and an articular cavity, with the long bone describing a series of circles and the whole forming a cone.
- In rotation movement, a bone moves about a central axis without moving from this axis. It is also known as articulation and arthrosis.