Referred pain is something that appears confusing as to why it happens so, but is clinically important as a sign to major underlying diseases. There are a number of theories of referred pain, but only some are relevant to medical world. Coming to point, the clinician might catch the disease of deep structures if he is able to use his awareness to catch out the referred pain. Apart from theories of referred pain, we will also see examples of referred pain. We shall discuss this topic more in detail to understand it better.
Referred pain is the experience of pain on a somatic structure that is not actually the cause of pain, while the actual deep structure is referring the pain to this somatic structure. In other words, the actual site of pain is transmitting it to another site. Let’s try to understand this in a more detailed fashion.
Theories and Mechanisms
Why does a patient of Myocardial infarction say he is having pain in arm, or why will a patient suffering from disease of gall bladder say he is having pain on tip of right shoulder? Yeah, that is indeed referred pain. Our brain is a complex and finest organ, but even the finest sometimes get confused. Why so? The following theory might just clear out some basics to figure it out. Let’s see the theories of referred pain in detail.
Accordingly, it is believed that the afferent nerve carrying sensation of pain (Nociceptor) from visceral and deep musculoskeletal structures end up in neuron in spinal cord (Spinal neuron). This spinal neuron also receives pain sensation from skin (somatic structures), and this is where it gets mixed up. Therefore, the pain sensation from a deep structure might be seen as pain coming from specific skin area and interpreted as pain in that region, and not a visceral pain. Overall, this results in referred pain from a deep visceral structure to a somatic structure as a mistake of brain to interpret two sensations.
Therefore, your patient is never going to tell you he is having pain of gall bladder, but on the tip of right shoulder.
Following are most important examples of referred pain which are worth remembering :-
|Visceral structure||Somatic structure|
|Diaphragm/Pleura||Right upper quadrant|
|Liver/Gall bladder||Left upper quadrant|
|Spleen||Tip of right shoulder|
|Heart (Myocardial infarction/MI)||Chest region radiating to right arm|
Sometimes, the Referred pain from different organ structures might coexist, and is always difficult to differentiate by the clinician. Nevertheless, practice makes a doctor perfect!
So, we discussed theories of referred pain and examples of referred pain. Hope you understood them for your future assessment.
It is the duty of a doctor to consider the patient and provide him the best treatment regimen, and that requires reaching the very root cause of disturbance. Sometimes, we actually miss out the most important signs in our clinical practice. This not only happens with novices, but experts who ignore the vulnerability of this profession. We hope you liked reading here, let us know anything in the comments box, we will be glad to reply upon.