Question

what is the significance of the formation of four curves ,one each in the neck ,thorax ,abdomen and pelvis region of the vertebral column of human beings?

Answer 1

Curves are a normal part of the spine's structure. Looking at the spine from the side (lateral), several curves can be seen he spine almost resembles a soft 'S' shape. When viewing the spinal column from the rear (posterior), the spine appears vertically straight -- from the neck to the tailbone.