Traction
Traction is a one dimensional, unilateral pull of the spine, not specifying any one segment. The downward intradiscal pressure when a person is standing is 100 mmHg of pressure. When generalized traction or inversion therapy is performed, the intradiscal pressure drops down to 40 mmHg of positive downward pressure. This is the point that muscle spasms can be relieved, however not enough to create a transfer of fluid from outside of the disc back into the nucleus pulposus or the center of the disc.
Differences in Inversion Therapy
Inversion therapy is just another form of generalized traction, pulling the ankles, the knees, the hips, the low back, the mid-back, and the neck, never creating enough of a decrease in the intradiscal space to allow for the transfer of the fluid outside of the disc back into the center of the disc.
Non-surgical Spinal Decompression Therapy
With Non-Surgical Spinal Decompression Therapy, the intradiscal pressure goes down to a negative 160 mmHg creating the transfer of fluid from outside of the disc into the center of the disc, vacuuming back in the protrusions or herniations as well.