There are big differences between traction and decompression.
One can experience traction without decompression, but not decompression without traction. Traction can be a machine, or just weights attached to your feet hanging over a bed as done in the past at hospitals. Decompression is a progressive event that is obtained by utilizing negative pressure, by vertebrae, on a specific angle, to achieve the "Vacuum Effect" or the event known as decompression.
Traction has been around for hundreds of years. Traction has been in use for many years as a physical-therapy modality. Forms of traction have been around for centuries.