spinal decompression NOT surgery in most cases

The most common spinal condition treated with decompression treatment is a herniated disc. Spinal compression can cause disc herniations to expand, putting pressure on surrounding spinal nerve roots. Decompression treatment takes the pressure off these damaged discs so that the disc bulge will shrink back closer to its original size.

Degenerative disc disease is also a common condition treated with decompression therapy. Loss of disc height can be exacerbated by spinal compression, causing the vertebral bodies to move closer together. This can cause nerve compression and other forms of common back pain. Decompression eliminates the overwhelming pressure on degenerated discs reducing or eliminating painful symptoms.

Facet joint syndrome is yet another condition treated with spinal decompression. Of all the conditions, this one shows the least promising results for permanent pain relief. Conceptually, facet syndrome causes pain due to arthritic changes in the vertebral bones. Decompression helps to create more space between the vertebrae, hopefully reducing painful symptoms.
Spinal Decompression Modalities
Forget about old fashioned attempts at decompression therapy. Pulley and weight spinal traction systems have never been proven to do anything, except injure patients in rare circumstances. Inversion therapy might create decompression of the spinal column, but is best left for fitness usage.
Cox Technic is a time tested form of decompression used primarily by chiropractors.

The modern versions of decompression therapy are Vax-D and the wonderful DRX9000. Another addition to the decompression industry is the Accu-Spina system. Check out these state of the art machines if you think that decompression therapy might be right for your form of back pain.
Recommendation on Spinal Decompression
I like decompression therapy as an excellent treatment option to avoid back surgery. Spinal surgery often has poor results for pain relief and has many risks and complications. It is always better to avoid surgery if at all possible...
I have studied the technology used by the DRX9000 and VAX-D systems and I must say that I am impressed. If you have tried several unsuccessful treatments for your back pain, consider decompression therapy as a final option. If your pain does not respond, it most likely indicates a misdiagnosis of the actual pain causing condition...