Phantom Limb Pain
Phantom limb pain refers to mild to extreme pain felt in the area where a limb has been amputated. Phantom limb sensations usually will disappear or decrease over time; when phantom limb pain continues for more than six months, however, the prognosis for improvement is poor
Why it Occurs
Although the limb is no longer there, the nerve endings at the site of the amputation continue to send pain signals to the brain that make the brain think the limb is still there. Sometimes, the brain memory of pain is retained and is interpreted as pain, regardless of signals from injured nerves.
In addition to pain in the phantom limb, some people experience other sensations such as tingling, cramping, heat, and cold in the portion of the limb that was removed. Any sensation that the limb could have experienced prior to the amputation may be experienced in the amputated phantom limb
Successful treatment of phantom limb pain is difficult. Treatment is usually determined based on the person’s level of pain, and multiple treatments may be combined. One approach that has gained a great deal of public attention is the mirror box developed by Vilayanur Ramachandran and colleagues. Through the use of artificial visual feedback it becomes possible for the patient to “move” the phantom limb, and to unclench it from potentially painful positions. Repeated training in some subjects has led to long-term improvement.
Some more standard treatments include:
•Biofeedback to reduce muscle tension
•Massage of the amputation area
•Surgery to remove scar tissue entangling a nerve
•TENS (transcutaneous electrical nerve stimulation) of the stump
•Neurostimulation techniques such as spinal cord stimulation or deep brain stimulation
•Medications such as pain-relievers, neuroleptics, anticonvulsants, antidepressants, beta-blockers, and sodium channel blockers.