Apart from being either acute or chronic, pain is also described according to its source in the body and the nociceptors, pain-detecting neurons, which can cause 'sympathetic' or referred pain in other areas of the body, or even give a feeling of pain in limbs which have been amputated.
This pain is related to injuries to the skin or tissues. It is usually defined and localized pain of relatively short duration, and may be caused by cuts, grazes, burns, lacerations and other injuries to the skin surface.
This pain is related to the ligaments, tendons, bones, blood vessels and nerves. It is usually a dull pain and poorly localized, so that it can be difficult for the sufferer to exactly locate where the pain is coming from. Common causes include sprains, sports injuries, broken bones and arthritis.
This pain originates from the body's viscera, or organs. This pain is characterised by a dull ache, and one that can be longer lasting than somatic or cutaneous pain. This pain is probably the hardest of all to properly locate, and injury to an organ can even be a referred pain that seems to occur elsewhere in the body. The best example of this is myocardial ischaemia, which is a sudden loss of the blood supply to the heart, usually from a blocked artery. Instead of being felt in the heart itself, the problem can manifest as pain in the upper chest as a restricted feeling, or as an ache in the left arm, shoulder or hand.
Phantom limb pain
This is the strange phenomenon of feeling pain in a limb that has been amputated. Most people who have lost a limb say they continue to feel sensations and pain in the lost limb.
This relates to pain in the nerves themselves, and is more commonly known as neuralgia. It is commonly caused by injury or disease to the nerve tissue. This pain can be the hardest to treat because the brain is, in fact, receiving wrong signals.