Helping Phantom Limb Pain

Helping Phantom Limb Pain
by Toni Ray

Over the years scientists have noted many complaints of a strange form of pain called phantom limb pain. This pain is strange because it is located in an appendage that no longer exists. By many of the amputees the pain is described as totally unbearable. Phantom limb pain has even driven some victims crazy. For the amputee population this is a very real problem that definitely needs to be solved.

After James Peacock had his right arm amputated last December, he expected some difficulties. With those difficulties came pain so unbearable it could not be controlled with all the medicine in his cabinet. Derek Steen, otherwise known as “The one-armed pool player,” lost a limb in a motorcycle accident at the age of 18. Although he lost the limb, he still plays a great game of pool. Nine years after the accident Steen continues to have pain in the missing arm. Deborah Finnegan-Ling, a graduate student in neuroscience, is writing her dissertation on phantom limb pain. Finnegan-Ling should know a lot about this phenomenon because three years ago, after a farming accident, her left leg was amputated. She has experienced much pain from this phantom limb especially in her personal life. The area of the brain for the foot is adjacent to the area for genitalia. Because of this connection Finnegan-Lingís missing limb aches when she makes love.”I consider myself tough,” she says.”But the pain is so acute that Iíll cry.”

Some amputees experience the opposite of phantom pain – phantom pleasure. One man tells about feeling an orgasmic sensation in his lost foot during sex. Finnegan-Ling sighs.”I wish,” she says.

Many scientists have studied amputees to determine the cause of this mysterious pain. Sussman (1995) concluded that the trouble starts in a part of the brain known as the sensory cortex. The sensory cortex carries a rough map of the body, called a homunculus or”little man.” Each body part in the homunculus is wired to its corresponding portion of the real anatomy. When a body part is lost the corresponding part of the brain is not able to handle the loss and rewires its circuitry to make up for the signals it was no longer receiving from the missing digit. The rewiring might occur in one of two ways. Perhaps nerve impulses in the sensory cortex begin to course down previously untraveled pathways. The second theory is that neighboring neurons in the cortex may actually invade the territory left fallow because sensations are no longer received from the missing limb.

Birbaumer, Lutzenberger, Montoya, and Wolfgang (1997) examined the functional relationship between cortical reorganization and phantom limb pain. Neuroelectric source imaging was used to determine changes in cortical reorganization in the somatosensory cortex after anesthesia of an amputation stump produced by brachial plexus blockage in six phantom limb pain patients and four pain-free amputees. This cortical reorganization was studied to examine whether the neurons rewired after the loss of an appendage.

Three of the phantom limb subjects experienced a virtual elimination of current phantom pain. The Biraumber et al., (1997) result of the anesthesia was a very rapid elimination of cortical reorganization in the somatosensory cortex. In three phantom-limb-pain amputees pain was not reduced by brachial plexus blockade. In the phantom pain-free amputation cortical reorganization remained unchanged. These findings suggest that cortical reorganization and phantom limb pain might have a causal relationship.

Flor, Elbert, Knecht, and Wienbruch (1995) also examined whether cortical reorganization (CRO) and phantom limb pain were positively related. Noninvasive neuromagnetic techniques were used to determine CRO in 13 amputees. A strong direct relationship was found between the amount of CRO and the magnitude of phantom limb pain experienced after an arm amputation. Data indicate that phantom limb pain is related to, and may be a consequence of, plastic changes in primary somatosensory cortex.

In addition to the physical contributions affecting phantom limb pain are the psychosocial factors. Dawson and Arnold (1981) investigated the role of psychological factors in ten patients (43-73 yrs old) with painful phantom limbs by means of a questionnaire and interviews. The hypotheses were that the severity of pain could be positively correlated with the subjectsí present personal problems and attitudes, or it could be correlated with their experience of pain in the limb before amputation. The results indicated that only the severity of pain positively correlated with the subjectsí present problems. Morris (1992) looked at the concepts of phantom limb pain in amputees. As psychogenic pain the pain is created or sustained by the mind. The clinical psychicians view pain not as a sensation, but as a perception. A review of the literature dating back to the Roman Emperor Marcus Aurelius suggests that pain is not always in oneís own head and that pain does not belong strictly to the mechanism of the body but rather to that of the mind and body, which are inextricably bound together.

In addition to physical and psychosocial factors, stress is also hypothesized to be a factor in phantom limb pain. Arena, Sherman, Bruno, and Smith (1990) examined the relationship between situational stress and phantom limb pain in 27 male, 71-yr-old amputees. The following possible relationships between the etiology and maintenance of phantom limb pain were examined: an isomorphic relationship (same-time increases in pain lead to same-time increases in stress and vice versa), a consequence relationship (increases in pain precede increases in stress), and a precursor relationship (increases in stress precede increases in pain). Although support was found for all three hypotheses, the most frequently observed relationship was the isomorphic one. Thirty-seven percent of subjects demonstrated some significant precursor relationship. Seventy-four percent of subjects demonstrated some significant stress-pain relationship. Their findings are discussed in terms of using psychophysiological interventions such as biofeedback in amputees with phantom limb pain.

Several relief approaches for phantom limb pain have been investigated including biofeedback, hypnosis, and relaxation. All three of these reliefs were found helpful. Arena et al., (1990) examined uses of biofeedback as a relief tactic. Tsushima (1982) used EMG and temperature biofeedback to treat phantom limb pain in a 51yr old man.

Nine EMG biofeedback sessions were effective in eliminating headache and reducing neck and chest pain excluding phantom limb pain. Four subsequent sessions involving temperature biofeedback and autogenic training were successful in eliminating phantom limb pain, which remained absent at a two month follow-up.

Wain (1986) tested how efficiently hypnosis treats phantom limb pain. Wain suggests that hypnosis bridges the gap between physiological and psychological conceptualizations of pain. The treatment of the pain sufferer is considered in terms of the therapeutic relationship and hypnotic trance, diagnosis, assessment of hypnotizability, induction procedures, and the development of a hypnotic strategy. It is emphasized that hypnosis promotes a milieu in which effective strategies can be integrated and the hypnotic techniques can give patients the needed impetus to recognize their ability to regain control.

McKechnie(1975) experimented with relaxation as a treatment for phantom limb pain. McKechnie reports observing relief from phantom limb pain in a young male adult patient with a nine-year history of such pain. Relief occurred during and after relaxation exercises focused on the phantom limb and was facilitated by practice. Six-month follow-up revealed continued relief. The relaxation technique is related to the hypnosis treatment by use the use of mind and body to control the pain in both techniques.

Although many studies point to cortical reorganization of the neurons as the result of this phantom limb pain, we have still not found a major way to extinguish this pain. In addition to cortical reorganization, scientists have studied psychosocial factors and stress as related to phantom limb pain. In the future, methods designed to alter cortical reorganization should be examined along with stress releasers, relaxation techniques, and pharmaceutical agents for their efficacy in the treatment of phantom limb pain.

References
Arena, J., Sherman, R., Bruno, G. & Smith J. (1990). The relationship between situation stress and phantom limb pain: Cross-lagged correlation data from six month pain logs. Journal of Psychosomatic Research, 34(1), 71-77.
Birbaumer, N., Lutzenberger, W., Montoya, P. & Larbig, W. (1997). Effects of regional anesthesia on phantom limb pain are mirrored in changes in cortical reorganization. Journal of Neuroscience, 17(14), 5503-5508.
Dawson, L. & Arnold, P. (1981). Persistent phantom limb pain. Journal of Perceptual and Motor Skills, 53(1), 135-138.
Flor, H., Elbert, T., Knecht, S. & Wienbruch, C. (1995). Phantom limb pain as a perceptual correlate of cortical reorganization following arm amputation. Journal of Nature, 375(6531), 482-484.
McKechnie, R. (1975). Relief from phantom limb pain by relaxation exercises. Journal of Behavior Therapy and Experimental Psychiatry, 6(3), 262-263.
Morris, D. (1992). The place of pain. Journal of Advances, 8(2), 3-24.
Tsushima, W. (1982). Treatment of phantom limb pain with EMG and temperature biofeedback. American Journal of Clinical Biofeedback, 5(2), 150-153.
Wain, H. (1986). Pain control with hypnosis in consultation and liaison psychiatry. Psychiatric Annuals, 16(2), 106-109.
Sussman, V. (October 1995). The route of phantom pain. U.S. News & World Report, 76-78.