When are different joints required?

A joint is the meeting point between bones and usually controls the amount of movement. Some joints have to be strong, while others need to be very mobile. As it is not possible for joints to be both strong and mobile we require many different kinds of joints:

Ellipsoid Joint: Allows circular and bending movement but no rotation

Saddle Joint: Allows movement in two directions, but without rotation.

Ball and socket joint: A joint freely moving in all directions.

Hinge Joint: Allows extension and flexion.

Condylar Joint: This is similar to a hinge joint, but with slight rotation to allow the joint to ‘lock’ into an extended position.

Pivot Joint: Allows rotation but no other movement.

Plane Joint: A flat surface allows the bones to slide on each other, but they are restricted by ligaments to a small range.

Fact File:

The knee joint is the largest and most complex joint in the body. As it reaches full extension it rotates slightly and ‘locks’ into a rigid limb from hip to ankle.

 

Picture Credit : Google