The Full form of PIVD is Prolapsed Intervertebral Disc. PIVD means the protrusion or extrusion of the nucleus pulposus through a rent in the annulus fibrosus. It has a four stages- Bulging, Protrusion, Extrusion, and Sequestration. Bulging is the early stage and in this stage, the disc is stretched and doesn’t completely return to its normal shape when pressure is relieved. It retains a slight bulge at one side of the disc. Some of the inner disc fibres could be torn and the soft jelly (nucleus pulposus) is spiling outwards into the disc fibres but not out of the disc. The next is Protrusion, at this stage, the bulge is very prominent and the soft jelly centre has spilled out to the inner edge of the outer fibres, barely held in by the remaining disc fibres. In Extrusion stage (in the case of a herniated spinal disc), the soft jelly has completely spilled out of the disc and now protruding out of the disc fibres and in Sequestration stage, some of the jelly material is breaking off away from the disc into the surrounding area. In Prolapsed Disc (commonly called a ‘slipped disc’), the part of the inner softer part of the disc (the nucleus pulposus) bulges out (herniates) through a weakness in the outer part of the disc.