Spinal decompression accomplishes two things. It increases the height between the vertebrae to create a negative pressure within a disc, which will then draw back the disc material. It also increases blood flow to the disc which will then allow the outer layer or the annular bands to start laying down new cartilage fibers, so that disc lesion can actually be without surgery.
The beauty behind spinal decompression is that it allows the blood to return back to the disc. The disc will begin healing once again. Blood is very essential to this whole process, increasing blood flow to the disc allows the natural healing process to occur.