Phantom Pain is a form of nerve pain appearing to arise from an area of the body that has been removed or amputated. This pain can affect mastectomy patients as well as patients with simple tooth extractions. Phantom sensations of some kind are almost universal in patients that have undergone limb amputations. Significant pain occurs in as much as 80% of these patients, but seems to improve over time in at least half of these patients.
The cause of phantom pain is not fully understood. It is important to emphasize that the pain is not imagined, and is not the result of a psychological or emotional disturbance.
Phantom pain is the prime example of neuropathic pain; i.e., pain that is caused by a damaged or malfunctioning nervous system. Therefore, all the medications that are used for neuropathic pain can be useful for phantom pain. This includes anti-convulsant and antidepressant medications. Transcutaneous electrical nerve stimulation (TENS) of the stump can occasionally provide relief. Interestingly, stimulation of the intact, opposite limb is often more effective. In some patients, rehabilitation with active exercise and use of the stump and a prosthesis can be the most beneficial treatment. Placement of spinal electrical stimulators has had mixed results, but if the pain has been refractory to all prior treatments then this should be considered.
It may be most appropriate to target the initial injury that precipitates the enduring neuropathic pain. In fact, this is already done by the use of pre-emptive anesthesia during surgery. The surgeon uses a local anesthetic to deaden the nerves as well as a general anesthetic to immobilize the patent for surgery. Another possibility may be to suppress the immune system for the initial five days after injury. This may curtail the inflammation associated with peripheral nerves that appears to trigger many aspects of neuropathic pain.
A recent article in Psychiatric Times by Steven A. King reported that while the “apparent neuropathic nature of phantom limb pain (PLP) would suggest that antidepressants, anticonvulsants and similar medications would be most efficacious. Most (PLP) patients are treated with acetaminophen, nonsteroidal antiinflammatories and opioids.” A survey article by M.A. Hanley and associates found that just over half of PLP patients, and over one-third of severe PLSP patients, “had never been treated” at all for their pain.