When is Pain Being Referred?

I recently wrote a blog on Pain and if its simply more than an experience.  To take this blog a step further, I wanted to get into differentially diagnosing referred pain vs. nonreferred pain.  As clinicians that typically treat patients who are in pain, it is vital that we recognize when pain is from musculoskeletal origin and when its being referred from somewhere else. 

To understand referred pain, we must understand how pain is referred and why it presents similar to musculoskeletal pain.  When we are little, we experience pain by falling, bumping into, or doing some sort of activity that causes a traumatic stimulus to our body.  This stimulus reaches cells within a sensory cortex and we have a memory of what that pain felt like.  As we age, we experience this pain numerous times through similar traumas/injuries—we even can sense or experience this stimuli through memory and almost “feel” that pain again.  Well on occasion, when the same cells in the sensory cortex get information from deeper structures, our brain interprets the information the same way it did from past experience.  The brain misinterprets the origin and we believe it is more superficial in nature when its actually deep.  Our body makes a perceptial error from the experience of pain.

Patients who experience true referred pain often compain of the following symptoms:

1. Deep burning or aching along a limb
2. Pain that radiates from the posterior aspect of the body anteriorly
3. Large, undefined boundaries of deep pain
4. The pain has no physical signs of disorder

A pain diagram is a great way of making a clinical mental note prior to even examining the patient.  Often if I see a patient draw big circles, put xxxxx’s to indicate burning along a limb or draw arrows showing the radiation of pain, I will ask more systemic questions in my history.  Because pain may be nothing more than experience, it is vital that we probe for its origin vs. always believing its musculoskeletal in nature. . .