For many people, they use a flat pillow at night and they have no issues. However, for some patients, namely those who suffer with neck pain, stiff neck, radiculopathy, numbness and tingling, degeneration (cervical spondylosis) or a disc herniation, using the right neck pillow can be the difference between sleeping at night or being in agony.
We can define a neck support pillow as a contoured neck pillow. One with neck rolls on it. Here is an example of such a pillow. Its called the arc4life linear gravity neck pillow.
To understand why a neck support pillow would be more beneficial, we have to first look at an x-ray of patient. First of notice that there are 7 bones that make up the cervical spine. C1- C7. Next notice that the spine is not a straight line, but rather you can make out a C curve. They call this a cervical lordosis. Simply by having this c curve naturally in our neck means that we should be using a curved pillow. The curve on the pillow should not be so big that pushes your head forward or is so low that you do not get adequate neck support.This particular c curve is also important for the nervous system and can relate to pain or discomfort if you don't have the natural c curve. In between each bone is a disc that acts as a shock absorber. Next to each disc on both sides are nerves that exit out. These nerves innervate the sensory, muscle and reflex of our upper extremity. If there is disc bulge or the spine is straight with no curve (called a hypolordosis or a military neck) then the nerves can be affected. When you put pressure on the nerves, interference can result: Neck pain, stiffness, numbness and tingling, less sensation, absent or diminished reflexes etc.
At the end of the day, this goes back to having the proper neck support when you sleep so that you maintain the proper alignment and integrity of the cervical spine and related structures. Keep in mind that these nerves in the neck affect your muscles and you feel directly. A proper neck support pillow with contoures allows you to have the c curve in your neck.