Pain can be referred to the neck in various ways, such as from the heart (during a heart attack) or jaw (temporomandibular joint). Conversely, a pathology in the neck can cause referred pain in other parts of the body, most commonly a headache, shoulder pain, or upper back pain.
When pain is experienced in a location other than its source and is not caused by nerve root irritation, it is called referred pain. It is usually experienced as a deep, achy, cramping and/or throbbing sensation. The area of distribution is likely to be more diffuse, or spread out, than radiating pain, but these two types of pain can feel similar. Referred pain is typically felt on only one side of the body, but it can be on both.
The mechanisms of how referred pain develops and spreads are still being studied. For example, when a trigger point (tender or hypersensitive part of a muscle) is compressed, the pain symptoms can be referred to other parts of the body. However, there is no firm agreement in the medical community about how trigger points develop and whether their pain patterns are predictable.