Any patient who undergoes an amputation, whether it be traumatic from an unexpected injury or from planned surgery, can develop phantom pain, stump pain, or both. Some studies suggest if a patient has pain in the area about to be amputated before the amputation, there is a greater likelihood of developing phantom pain.
Following an amputation, abnormal sensations can be felt from the amputated body part; that is, a patient may feel sensations in a limb (or any other amputated body part), which is no longer part of his/her body. In fact, these unusual phantom sensations occur in most people following amputation. The sensations can be changes in size or position, or actual feelings of heat, cold, or touch. In some patients, these abnormal sensations include pain. Because the pain is experienced in a part of the body that is no longer present, it is called phantom pain. Luckily, for most patients, both the phantom sensations and pain gradually resolve with time.
The actual cause of phantom pain is not known. Most authorities currently believe that both phantom pain and other phantom sensations are generated from the spinal cord and brain. It is believed that when a body part is amputated, the brain region responsible for perceiving sensation from that area begins to function abnormally, leading to the perception that the body part still exists.
Treatment of Phantom Pain
The treatment of phantom pain is difficult. No one treatment has shown to be effective in a majority of sufferers. Fortunately, there are treatment approaches that may be helpful in some patients.
- Antiseizure drugs (such as gabapentin, carbamazepine, topiramate)
- Antidepressants (such as amitriptyline, nortriptyline)
- Local anesthetics (such as mexiletine)
- Alpha-2 adrenergic agonists (such as clonidine or tizanidine)
- Others, including calcitonin, baclofen, dextromethorphan
- Opioids (such as morphine, oxycodone, methadone)
- Nerve blocks
- Spinal Cord Stimulation
- Implantable Drug Administration System (Intrathecal Pump)
- Hypnosis, biofeedback, and other cognitive techniques (such as relaxation training and distraction)
Stump pain is located at the end of an amputated limb’s stump. Unlike phantom pain, it occurs in the body part that actually exists, in the stump that remains. It typically is described as a “sharp,” “burning,” “electric-like,” or “skin-sensitive” pain.
Stump pain is due to a damaged nerve in the stump region. Nerves damaged in the amputation surgery try to heal and may form abnormally sensitive regions, called neuromas. A neuroma can cause pain and skin sensitivity.
Treatment of Stump Pain
No one treatment has been shown to be effective for stump pain. Because it is a pain due to an injured peripheral nerve, drugs used for nerve pain may be. If the stump pain affects a limb, revision of the prosthesis is sometimes beneficial. Other approaches also are tried in selected cases, including:
- Nerve blocks
- Transcutaneous electrical nerve stimulation (TENS)
- Surgical revision of the stump or removal of the neuroma (This procedure may fail because the neuroma can grow back; some patients actually get worse after surgery.)
- Cognitive therapies