We associate the neck and upper back together, because most of the muscles that are associated with the neck either attach to, or are located in, the upper back. These muscles include the trapezius, the levator scapulae, the cervical paraspinal muscles and the scalenes, as well as others.
Most neck and upper back pain is caused by a combination of factors, including injury, poor posture, chiropractic subluxations, stress, and in some instances, disc problems.