A neutral position for any part of the body is usually one in which the part is in the middle of two extremes of motion. For the back or spine, "neutral" means a place with the least rotational stiffness.

In the normal back without deformities or injuries, neutral consists of three natural curves. The neck is slightly extended, the upper back is flexed, and the low back is slightly extended. The "neutral" position can be assumed whether standing, sitting, kneeling, or on hands and knees.

Neutral position differs slightly for each person. There are two ways to teach neutral spine positioning. The therapist may use his or her own visual judgment. It’s also possible to use a machine that measures positions and angles of the spine. Most clinics don’t have this device and rely on tester judgment.