The normal cervical curve or cervical lordosis is approximately 43 degrees. I say approximately because it can be anywhere from 40-60 degrees to function at its best. Any loss of the curve will increase the pressure gravity puts downward on the head. This will lead to breakdown and cervical degeneration which in turn often creates neck pain and loss of neck motion.

A study from Practical Pain Management showed the effects of the posture pump neck traction to be superior to linear traction. What this means is that tractioning with the posture pump is more successful at restoring the neck curve than straight axial traction. This is analogous to someone pulling your head straight up, where as the posture pump traction you have a stretch but also a lobe that pumps up under the neck to restore the curve.