Phantom Limb Pain
What is Phantom Limb Pain?
Phantom limb pain is pain experienced by a person who has had a limb removed (amputated), through trauma or medical necessity, but still feels pain in the region of the removed limb. It feels like the limb is still there and that it is a painful limb. It's called 'phantom' because the limb is not real.... but the pain is very real! As well as pain, the limb might feel larger or smaller, tingly, burning, tight or fuzzy, or various other 'sensations'.
How is a limb painful when it isn't really there?
The brain receives sensory information from each part of your body so that it can 'know' what's happening in your body at any time and control it, move it, park it etc.. When you touch your arm, the sensation reaches the spinal cord and goes to the brain's sensory cortex. The part of the sensory cortex which represents the arm 'lights up', informing you that the sensation comes from your arm. However, when the arm is amputated, and the sensory cortex still lights up when stimulated, the brain interprets that 'lighting up' as a stimulus coming from the arm. therefore, the fault is in the brain's sensory cortex, not the arm.... which isn't there.
When a sensory stimulus a painful one?
When the brain cannot interpret the stimulus logically, an illogical stimulus is threatening to the brain as it could be dangerous.
So the brain may generate the pain and/or amplify the stimulus into pain to alert you to the threat.
What can be done for phantom limb pain?
The brain can be retrained so that it no longer interprets the information in the sensory cortex as coming from the 'limb'. Sensory processing can be altered using tactility training strategies and mirror therapy. If there is also pain amplification through central sensitisation then effective pain science education and lifestyle alterations can be very useful in reducing the pain experience and reducing pain-related disability.