Referred Pain

Referred pain is a phenomenon wherein the pain that occurs in one part of the body is perceived in some other part of the body.

When my father had his heart attack, there was no pain anywhere at or near his heart; instead, he experienced a diffuse pain in his left shoulder and arm. What we did not know at that time was that this was a classic case of referred pain.

This is the case where there is pain in a body part, distinct from that receiving the pain stimulus. The pain is said to be referred to a body part from a stimulus in some other body part! So, even though it was my father's heart that was actually affected, he felt the pain in his arm instead.

Some people may feel the pain of a heart attack, or angina pectoris, in the neck or even the back.

• Shoulder Pain: This can be caused by a disorder in the liver, gastric ulcer, gallstone, pericarditis, pneumonia, or rupture of the spleen.

• Ice Cream Headache: Also known as 'brain freeze', this is caused by the vagus nerve being cooled when the throat is cooled by eating something cold, such as ice cream.

• Appendicitis Pain: Sometimes people with acute appendicitis feel the pain in the right shoulder, and not in the abdomen.
• Pain in a Phantom Limb: A pain sensation felt from a limb that is no longer there or from which no physical signals are sent. This type is very common in people with amputated limbs and quadriplegics.

Referred pain should not be confused with another seemingly similar phenomenon known as radiated pain. For example, if a person suffers a herniated disc, there will be pain in the back as well as in the leg.

This happens because the affected nerve happens to travel from the pine to that part of the leg, hence the pain radiates through that pathway. However, pain travels through unusual nerve pathways.

It is still not known precisely what connections in the human body cause referred pain, but there are a few theories that explain quite plausibly what may cause this kind of bizarre phenomenon. 

Basically, pain occurs due to the nerve fibers in areas that have high levels of sensory input, like the skin, and the nerve fibers from areas that usually have low levels of sensory input, like internal organs, happen to come together in the same area of the spinal cord.

Therefore, during my father's heart attack, the nerves from the damaged tissue of his heart were conveying signals to T1-T4 levels of his spinal cord, on the left side, which also are the levels which perceive sensation from a portion of the left arm as well as the left side of the chest.

Since the brain is unused to getting such strong pain signals from the heart, it deciphers that the pain is coming from the left arm, or in the chest.

One of the best ways of dealing with referred pain is to keep track of the characteristics of your pain and provide this information to your doctor. In case the area you feel pain is found to be normal, then an X-ray ought to be taken of other parts of the body that could be the real source of the pain.

Then, discuss with your physician about the treatment options available to you according to the diagnosis made, which could include physical therapy, drug therapy, or surgical intervention.