Phantom pain is an unpleasant sensation that occurs in relation to a body part, particularly a limb or organ that is not physically present. It is often felt most especially by amputees but may also occur on patients with congenital limb deficiencies, spinal cord injuries (SCIs), and to patients who have undergone mastectomy.
It must be made clear that phantom pain is different from phantom sensation. Although they are linked to one another, the difference is very distinct. A phantom limb sensation occurs as any sensation in relation to the absent body part. The phantom sensation occurs more often than pain. Up to 98% of people who have undergone removal of a body part reports some kind of sensation on it.
Amputees may describe their amputated limbs to still be functioning like they normally did. Some amputees report that the absent limb feels as heavy as the normal one. They may also feel “telescoping,” where the amputated part feels like it’s shrinking over time. Others have also reported feeling movement, touch, pressure, tingling, and itchiness. And from there, you also get pain which is medically known as the phantom pain.
Researchers are not sure how this occurs and all the explanations available today are based on theories, some overlapping others. The basic principle in phantom limb pain is that when the brain loses input from the amputated part, it may adjust to it in unpredictable ways, hence the different description of phantom sensation. The point here is that the brain has been so used to getting inputs from the now missing body part that it doesn’t know exactly how to react from the loss of input signals. And sometimes, it decides to take on its most primitive way of telling that something is wrong and sends pain signals to its working nerve network.
Currently, there is no medicine specifically made for phantom limb pain and drug treatment for this condition consists of different types of drugs used predominantly for other health problems. Antidepressants may help by altering the chemical messengers of the body. Anticonvulsants are also used to help calm the damaged nerves and slow or even prevent the transmission of pain signals. If the pain is severe, to the point that it prevents the amputee from functioning, narcotics may be prescribed after exhausting other less powerful analgesics.
Other treatments may be used in conjunction with the drugs. An example is a kind of nerve stimulation called transcutaneous electrical nerve stimulation (TENS). It works by sending weak electrical charges into the skin adjacent to the area of pain. The myoelectric prosthesis possesses a motor that runs by electrical charges sent during a voluntary movement. Phantom pain is relieved in some amputees after applying this device. The mirror box has also been observed to help eliminate the phantom limb pain in a number of patients. This works by positioning both limbs (the good limb and amputated part, what’s left of it that is) in front of a mirror and doing symmetrical exercises. The image on the mirror serves to help the amputee give a clear visualization of the missing limb and pretend that it’s still there. This works in many patients.