When you crack your neck and back, it often feels good afterwards, especially if there was a great deal of tension or pain prior. The reason it feels good is because pressure is being relieved. Just as when any of your joints crack, gases are being released from within the synovial membranes. This release can cause a temporary relief of pressure or pain. In most cases though, the pressure or pain will return.
Many people can forcibly crack their joints, even their neck and back. In some cases, such as when performing stretching or yoga exercises, natural movement may also cause cracking. You might also visit a chiropractor who will crack your neck and back through a series of manipulations. While these manipulations can relieve pain and pressure in these areas, there are some studies that indicate cracking the neck may be linked to an increased risk of stroke.
If you forcibly crack your neck or back frequently, especially as a means to relieve pressure and pain, you might consider visiting a chiropractor or other medical professional. In some cases, chronic neck cracking can lead to loss of elasticity in the ligaments, which forces the muscles to work harder and tire easier. This happens when the joints are forced beyond their normal range of motion and the ligaments stretch out over time. When they do not return to normal, this causes a condition known as hypermobility.
When you crack any body part, you should avoid forcibly stretching your joints beyond the normal range of motion. If you experience frequent neck and back pain, which may or may not be relieved when you crack them, you should visit a healthcare professional. There could be underlying causes for the pain, including injury or a degenerative condition.