Although most spine surgery has a component of decompression, spinal decompression surgery is usually meant to mean surgery done to get pressure off of the spinal cord or several nerve roots.  In the neck, spinal decompression surgery is done to remove disc and/or boney tissues off of the spinal cord.  In the low back, spinal decompression surgery is usually done to remove disc, boney, cartilage and/or ligamentous tissues off of the nerve roots.  If the spinal compression is not too severe, then spinal decompression can be accomplished non-surgically, instead of surgically.