Historically, the most commonly performed operation for back pain has been spinal fusion. There are a variety of ways this is done but the basic idea is to take the painful segment of the spine and get it to become a solid piece of bone. This will eliminate motion and, in theory at least, if it doesn't move, it shouldn't hurt. This can be done through the back (posterior) or through the front (anterior), or sometimes both ways. Spinal fixation of some sort is often combined with some form of bone graft or bone substitute. Bone graft can either be obtained from another part of the skeleton such as the pelvis or be donated bone that is processed and used in a spine fusion. The results of spine fusion for low back pain vary. A good result is a decrease in pain. It is very rare for someone to be completely out of pain after a spine fusion. Full recovery can take more than a year.