Phantom pain is a pain that feels like it is coming from a body part that no longer exists. Scientists once believed this post-amputation phenomenon was a psychological issue. But experts later recognized that these are real sensations, originating from the spinal cord and the brain.
Phantom pain is a type of perception that a person experiences related to a limb or an organ of the body that is no longer a physical part of the body. Phantom pain can also arise following nerve avulsion or due to an injury to the spinal cord. These sensations are recorded most commonly following the amputation of a leg or an arm. However, they can also arise following the removal of a breast, teeth, or an internal body part.
The characteristics of phantom pain typically include:
- Onset within the first week after amputation, although it could be delayed by months or even longer than that
- Pain, which comes and goes or is constant
- Symptoms affecting a limb’s part farthest from the body, such as the foot of a leg after amputation.
- Pain that may be defined as shooting, cramping, stabbing, pins or needles, throbbing, burning, etc.
When to See a Doctor
The pain of a phantom limb often occurs shortly following amputation. It can also start months or years later. If you have undergone amputation and you are suffering phantom limb sensations, consult your doctor as soon as possible.
What are the Causes of Phantom Pain?
Though the exact cause is uncertain, it seems to emanate from the spinal cord and brain. During scans like PET or MRI, the parts in the brain that had been connected neurologically to the nerves of amputated limb show some activity when the person feels phantom pain.
After amputation, areas of the brain and spinal cord also lose signals from the amputated limb and adjust to this detachment in irregular ways like pain.
Research also show that after amputation, the brain may remap that part of your body’s sensory circuitry to another part of your body. So when that part is touches, it feels as if the removed limb is being touched.
What are the Types of Phantom Pain?
There are numerous types of sensations a patient can feel. These are:
- Sensations that relate to the phantom limb’s posture, volume, and length: This refers to feeling that the phantom limb’s behavior is similar to a normal limb. For example, feeling the phantom limb when sitting with a bent knee or feeling that the phantom limb is heavy like the other limb. Many times, an amputee will suffer a sensation known as telescoping, the feeling that the phantom limb is slowly becoming smaller with time.
- Sensations of movement: For example, feeling that the phantom foot is moving.
- Sensations while touching or the sensations of temperature, pressure, and itching: Many amputees complain of feeling hot/cold, an itch, or a tingling sensation, and sometimes, pain.
In less critical cases where minor digits are amputated, the sensation can be described as a tingling feeling as opposed to a sensation of pain. Not everyone who has an amputation develops phantom pain.
How Can You Prevent Phantom Pain?
Some doctors recommend regional anesthesia to patients as the risk of developing phantom pain is higher for those who have experienced pain in the limb before amputation. This method increases the chance of pain reduction immediately following surgery and decreases the risk of lasting phantom limb pain in the long term.
What are the Treatment Options for Phantom Pain?
There are numerous methods through which the treatment of phantom limb pain is possible. Doctors may give prescription medication to reduce limb pain. Some antidepressants or antiepileptics have been proven to have a useful effect in reducing phantom limb pain. Some physical methods such as light massage, hot and cold therapy, and electrical stimulation have often been used with variable outcomes.
There are several different treatment options for phantom limb pain presently being studied by researchers. Many treatments do not address the problem well and are therefore unsuccessful. However, some treatment options have been proven to lessen the pain in some patients.
Some examples of medications used are:
- Over-the-counter (OTC) pain relievers
- Narcotics: Opioid medicines like morphine and codeine, may be an option for some people
- N-methyl-d-aspartate (NMDA) receptor antagonists like dextromethorphan and ketamine helped relieve phantom pain
- Mirror box: This device has mirrors that make it look like an amputated limb exists. The person can then perform symmetrical exercises while looking at the intact limb move and imagining that he/she is actually observing the missing limb moving.
- Repetitive transcranial magnetic stimulation (rTMS)
- Spinal cord stimulation
- Brain stimulation: Motor cortex stimulation and deep brain stimulation are like spinal cord stimulation except that the current is delivered within your brain.
Phantom limb pain arises more commonly in patients who also suffer longer periods of stump pain and is more likely to decrease as the stump pain decreases.
Frequently Asked Questions (FAQs)
Does phantom pain ever vanish?
Phantom pain eventually goes away with time. Several patients find that their pain has reduced by about 75% or more within a period of 2 years after amputation.
Why do amputated patients feel phantom pain?
Several experts believe that phantom pain may be explained partly as a response to mixed signals from the brain.
Do dogs feel phantom pain too?
They too experience discomfort and pain after a limb is lost.