Que. Slipped Disc is one of the frequent causes of Backache. What are the function / purpose of Disc? What is Sciatica? What is PID? Answer : Between two adjacent vertebras is fibro cartilage (rubber washer like) structure. This is called as Inter vertebral Disc. The Function of this disc is to prevent friction of vertebra on each other, reduce the shocks on the vertebral column, prevent the degeneration of vertebra; it also gives the Flexibility to the vertebral column.