Phantom Limb Pain
What is Phantom Limb Pain?
Phantom limb pain is a painful or unpleasant sensation in a body part that has been amputated. The sensation may occur immediately following surgery, or years later. Phantom pain is different from stump pain (or residual limb pain), which is localized in the remaining body part, or stump.
At one time, phantom pain was thought to be a psychiatric illness. Now we understand that it occurs through complex biological mechanisms. These involve changes in your brain’s sense of the affected part, changes in how sensation is processed in your nerve pathways, and changes due to damage of the nerve at the amputation site. Phantom limb pain can be influenced by psychiatric stress and depression, but it does not result from these conditions.
Factors associated with a higher risk of acquiring phantom limb pain include:
Pain prior to amputation
Pain prior to amputation of higher intensity and longer duration
Residual pain in the nonamputated part of the limb
Research is incomplete regarding who will or will not experience phantom limb pain. To date, there are no clear predictors of the condition.
How Does it Feel?
Phantom limb sensation, stump pain, and phantom limb pain are common experiences following an amputation. Up to 95% of amputees will experience at least 1 of these conditions.
Phantom limb sensation is a nonpainful feeling or sensation in the body part that was amputated. Phantom sensations are more commonly reported than stump pain or phantom limb pain. The sensations feel like the limb felt before the amputation, and are related to the same sense of awareness that helps people distinguish “myself” from others. The sensations occur from the interaction of current sensory inputs from your limb, and the internal “models” of the body in the brain.
Early on, the phantom limb resembles the limb shape prior to amputation. It may be perceived in a certain position, have feelings of warmth or cold, itching, or tingling.
Following amputation, it is common to “forget” your limb is absent and to attempt using it—a sensation that can result in a fall for a lower-limb amputee.
It is also common for amputees to feel as though the upper portion of the limb is missing, or has shrunk. This phenomenon, called telescoping, is caused by a change in the internal model of the body in the brain. It can also cause the sensation that the amputated part of the limb is floating, or has even moved up inside the stump.
Stump Pain is common in the postoperative period. It is felt only in the remaining body part, or stump. Stump pain may be felt at the incision or deeper into the residual limb. This pain is often described as sharp, burning, stabbing, or “electric.” Stump pain, which normally fades as the surgical scar heals, can coexist with phantom limb pain.
Phantom Limb Pain is a painful or unpleasant sensation in the lost body part. Sensations can include:
Tingling, burning, and cramping (the most common pain felt by amputees)
Shooting, stabbing, boring, squeezing, or throbbing pain
Pain just like that experienced at the time of the accident or serious injury
A feeling like the phantom limb is in a forced and uncomfortable position
Since phantom pain is related to the brain and nervous system, it can also be experienced in the nonamputated part of the limb, in the opposite nonamputated limb, or even in the neck or back.
Phantom limb pain usually affects the part of the limb farthest from the body. For example, lower-limb phantom pain will usually be experienced in the toes, heel, instep, or top of the foot. The pain may be continuous, or it may come and go during the day. In many cases it occurs randomly.
Phantom pain may be triggered by:
Pressure on the remaining part of the limb from objects such as clothing
Forgetting the limb’s absence and attempting to use it
A poorly fitting artificial limb
How Is It Diagnosed?
There are no medical tests to diagnose phantom limb pain. Diagnosis is made based on your symptoms and the history of what occurred before the pain started. For example, was there illness, trauma, or surgery before the amputation? Reporting clearly and precisely what seems to trigger the phantom pain will help your physical therapist diagnose the problem. The therapist may have you complete questionnaires about your symptoms and functional difficulties to help clarify details of your problem and how it is affecting your daily life and activities. All other possible sources of your pain symptoms must be ruled out.
Your physical therapist will:
Perform a careful examination of the bone and soft tissues of your stump to identify possible skin breakdown, infection, or abnormal pressure on weight-bearing contact points.
Gently tap on the stump to identify possible nerve injury or a neuroma (an overgrowth of nerves in the stump).
Check the fit of your prosthetic limb. (It is common for the shape of your stump to change over time, affecting the prosthetic’s fit and comfort.)
Check to make sure you are using the correct stump socks, and that you are putting your prosthetic on properly.
Explain how any of the above changes can cause skin breakdown and provoke pain problems.
Your physical therapist will work with your physician to determine the need for additional tests to rule out other conditions such as poor circulation, and may take x-rays to identify bone spurs or other abnormal bone formations.
How Can a Physical Therapist Help?
Phantom limb pain needs to be managed to prevent symptom flare-ups, or to resolve the problem. Pain management includes treating the biological and complex mechanisms of the problem with different strategies. A symptom-specific approach includes the use of medication prescribed by the physician, psychological and behavioral therapies, and at times surgical intervention.
Your physical therapist may provide hands-on treatment and other interventions and exercises.
Physical treatments may include:
TENS (transcutaneous nerve stimulation)
Stump sock/shrinker use
Prosthetic fittings, and proper use training
Treatment that focuses on improving how the nervous system is processing sensations from the amputated limb can help change the brain’s representation or body image of the affected part and improve conduction of the sensory nerve pathways. Your physical therapist may prescribe the following interventions/exercises:
Desensitization. This treatment helps modify how sensitive an area is to factors like clothing pressure or touch.
Graded motor imagery-movement imagery training. These imagery exercises help your brain process information about your amputated limb more accurately. It helps you form a clearer image of the affected limb to improve or resolve phantom pain.
Mirror visual feedback/Mirror box therapy. This treatment uses a mirror or mirror box to “trick” your brain into believing the reflection of your nonamputated limb is actually your opposite limb. The brain also perceives the limb it is seeing is the involved side, and sees it as the complete limb. The brain changes and adapts how it processes perception and sensation of the amputated limb like the normal side. This improved processing helps you to reduce phantom sensations.
The above exercises should only be performed under the guidance of a trained physical therapist. For more detailed information on what these treatments involve, see the references below.
Can this Injury or Condition be Prevented?
There is no clear evidence that phantom limb pain can be prevented. Pain management that eliminates symptoms before and after amputation may help limit the onset of pain and even prevent it. However, some people will still get phantom limb pain even with excellent pain management.
Real Life Experiences
Bill underwent an amputation of his right lower leg due to severe circulatory problems and infection. He experienced a lot of pain and discomfort with this illness and was unable to walk because of it. He was treated for his pain prior to his amputation and felt some improvement. Bill complained of pain and burning in his stump after the surgery. His physical therapist, Joan, performed a careful examination of the bone and soft tissues in his stump to identify possible skin breakdown, infection, or abnormal pressure points. Joan helped Bill with the stump pain by applying appropriate stump shrinkers for compression, massage of the stump, electrical stimulation and exercise to improve his symptoms.
Since the amputation, Bill is also noticing that it feels like his amputated leg is still there. He feels his foot itching at times. He even forgot his leg was amputated and tried to stand up on it, almost falling.
Bill’s physical therapist explains that what he is experiencing is phantom-limb sensation. She assures him that this sensation is very common after amputation and can improve over time. She helps him learn how to move and walk safely with his amputation.
A few weeks later, Bill tells his physical therapist that he is experiencing intermittent burning and tingling sensations in his amputated limb. He thinks the pressure of his pants leg could be causing the pain. His physical therapist teaches him about phantom limb pain. She prescribes exercises to help improve his perception of his right leg and the brain’s representation or body image of the affected part.
Bill learns and practices desensitization of the stump, mirror visual feedback/mirror box exercises, and movement imagery training over the next several weeks.
Bill begins to notice his symptoms are not as easily triggered and do not occur as much. He has also started using his prosthetic leg more. His physical therapist works with his prosthetist to ensure the prosthesis continues to fit well. She continues to train Bill on the proper use of the prosthetic leg, and is helping him increase the amount of time he wears it daily. Bill continues his program daily with less phantom pain as well as improved strength, walking, and well-being.