What is the phenomenon known as phantom limb pain, and how do you reduce the pain of something that isn’t there?
For many years, people tried to solve the case of the phantom limb sensation. They believed the Freudian theory that the pain is part of a mourning process for the lost limb. These days, the go-to explanation is that it is confusion in the brain’s relation to its body.
Globally, amputations are performed at the bone-rattling rate of one amputation every 30 seconds. That means that there are more than one-million new amputees each year and almost every single one of them will experience phantom limb pain. These sensations, which are felt where the limb used to be, can be a shooting, burning or stabbing pain, and may also take the form of electric shocks and cold sensations. I know of patients getting up in the middle of the night and falling because they completely forgot that the limb is no longer there.
These sensations might decrease in intensity over time, but they may never go away completely.
For as I long can remember, many experiments have been carried out to try and “trick” the brain into thinking that the amputated limb is still there, or accepting that it is no longer there. These experiments also try to persuade the brain that there’s no need to take revenge on the body by causing blood-curdling pain. These experiments can sometimes be successful, but mostly they’re not.
But now someone has come up with a new answer – it’s not the brain, it’s the body!
In a recent study, Israeli and Albanian researchers have found the primary source of phantom limb syndrome is a bundle of nerves near the spine – and they managed to alleviate the associated pain. Their work shows that phantom limbs are not “imagined” in the brain, but “felt” in the body.
Guided by medical imaging, the researchers injected 31 lower limb amputees with local anaesthetic near the area where the nerves from their amputated legs entered the spinal cord. Within minutes, phantom limb sensation and pain were temporarily reduced or eliminated in all the amputees. The researchers say: “The neurons in the spinal cord probably begin terrorising the brain with abnormal signals when the limb they innervate is amputated, causing the pain and other sensations associated with phantom limb syndrome. The anaesthetic appears to block signals associated with the syndrome from reaching
the brain.”
I have noticed that wearing a prosthetic limb significantly reduces the number of complaints about phantom limb pain. It is a positive thought that amputees have at least one more solution to their discomfort. Doctors may be able to “amputate” phantom limbs for the first time in a thousand years, and the words “mind over matter” can have a whole new meaning for amputees.
Heinrich Grimsehl is a prosthetist in private practice and a member of the South African Orthotic and Prosthetic Association (SAOPA). email: info@hgprosthetics.co.za
