by Toni Ray
Over the years scientists have noted many complaints of a strangeform of pain called phantom limb pain. This pain is strange becauseit is located in an appendage that no longer exists. By many of theamputees the pain is described as totally unbearable. Phantom limbpain has even driven some victims crazy. For the amputee populationthis is a very real problem that definitely needs to be solved.
After James Peacock had his right arm amputated last December, heexpected some difficulties. With those difficulties came pain sounbearable it could not be controlled with all the medicine in hiscabinet. Derek Steen, otherwise known as "The one-armed pool player,"lost a limb in a motorcycle accident at the age of 18. Although helost the limb, he still plays a great game of pool. Nine years afterthe accident Steen continues to have pain in the missing arm. DeborahFinnegan-Ling, a graduate student in neuroscience, is writing herdissertation on phantom limb pain. Finnegan-Ling should know a lotabout this phenomenon because three years ago, after a farmingaccident, her left leg was amputated. She has experienced much painfrom this phantom limb especially in her personal life. The area ofthe brain for the foot is adjacent to the area for genitalia. Becauseof this connection Finnegan-Lingís missing limb aches when shemakes love."I consider myself tough," she says."But the pain is soacute that Iíll cry."
Some amputees experience the opposite of phantom pain - phantompleasure. One man tells about feeling an orgasmic sensation in hislost foot during sex. Finnegan-Ling sighs."I wish," she says.
Many scientists have studied amputees to determine the cause ofthis mysterious pain. Sussman (1995) concluded that the troublestarts in a part of the brain known as the sensory cortex. Thesensory cortex carries a rough map of the body, called a homunculusor"little man." Each body part in the homunculus is wired to itscorresponding portion of the real anatomy. When a body part is lostthe corresponding part of the brain is not able to handle the lossand rewires its circuitry to make up for the signals it was no longerreceiving from the missing digit. The rewiring might occur in one oftwo ways. Perhaps nerve impulses in the sensory cortex begin tocourse down previously untraveled pathways. The second theory is thatneighboring neurons in the cortex may actually invade the territoryleft fallow because sensations are no longer received from themissing limb.
Birbaumer, Lutzenberger, Montoya, and Wolfgang (1997) examined thefunctional relationship between cortical reorganization and phantomlimb pain. Neuroelectric source imaging was used to determine changesin cortical reorganization in the somatosensory cortex afteranesthesia of an amputation stump produced by brachial plexusblockage in six phantom limb pain patients and four pain-freeamputees. This cortical reorganization was studied to examine whetherthe neurons rewired after the loss of an appendage. Three of thephantom limb subjects experienced a virtual elimination of currentphantom pain. The Biraumber et al., (1997) result of the anesthesiawas a very rapid elimination of cortical reorganization in thesomatosensory cortex. In three phantom-limb-pain amputees pain wasnot reduced by brachial plexus blockade. In the phantom pain-freeamputation cortical reorganization remained unchanged. These findingssuggest that cortical reorganization and phantom limb pain might havea causal relationship.
Flor, Elbert, Knecht, and Wienbruch (1995) also examined whethercortical reorganization (CRO) and phantom limb pain were positivelyrelated. Noninvasive neuromagnetic techniques were used to determineCRO in 13 amputees. A strong direct relationship was found betweenthe amount of CRO and the magnitude of phantom limb pain experiencedafter an arm amputation. Data indicate that phantom limb pain isrelated to, and may be a consequence of, plastic changes in primarysomatosensory cortex.
In addition to the physical contributions affecting phantom limbpain are the psychosocial factors. Dawson and Arnold (1981)investigated the role of psychological factors in ten patients (43-73yrs old) with painful phantom limbs by means of a questionnaire andinterviews. The hypotheses were that the severity of pain could bepositively correlated with the subjectsí present personalproblems and attitudes, or it could be correlated with theirexperience of pain in the limb before amputation. The resultsindicated that only the severity of pain positively correlated withthe subjectsí present problems. Morris (1992) looked at theconcepts of phantom limb pain in amputees. As psychogenic pain thepain is created or sustained by the mind. The clinical psychiciansview pain not as a sensation, but as a perception. A review of theliterature dating back to the Roman Emperor Marcus Aurelius suggeststhat pain is not always in oneís own head and that pain doesnot belong strictly to the mechanism of the body but rather to thatof the mind and body, which are inextricably bound together.
In addition to physical and psychosocial factors, stress is alsohypothesized to be a factor in phantom limb pain. Arena, Sherman,Bruno, and Smith (1990) examined the relationship between situationalstress and phantom limb pain in 27 male, 71-yr-old amputees. Thefollowing possible relationships between the etiology and maintenanceof phantom limb pain were examined: an isomorphic relationship(same-time increases in pain lead to same-time increases in stressand vice versa), a consequence relationship (increases in painprecede increases in stress), and a precursor relationship (increasesin stress precede increases in pain). Although support was found forall three hypotheses, the most frequently observed relationship wasthe isomorphic one. Thirty-seven percent of subjects demonstratedsome significant precursor relationship. Seventy-four percent ofsubjects demonstrated some significant stress-pain relationship.Their findings are discussed in terms of using psychophysiologicalinterventions such as biofeedback in amputees with phantom limb pain.
Several relief approaches for phantom limb pain have beeninvestigated including biofeedback, hypnosis, and relaxation. Allthree of these reliefs were found helpful. Arena et al., (1990)examined uses of biofeedback as a relief tactic. Tsushima (1982) usedEMG and temperature biofeedback to treat phantom limb pain in a 51yrold man. Nine EMG biofeedback sessions were effective in eliminatingheadache and reducing neck and chest pain excluding phantom limbpain. Four subsequent sessions involving temperature biofeedback andautogenic 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 limbpain. Wain suggests that hypnosis bridges the gap betweenphysiological and psychological conceptualizations of pain. Thetreatment of the pain sufferer is considered in terms of thetherapeutic relationship and hypnotic trance, diagnosis, assessmentof hypnotizability, induction procedures, and the development of ahypnotic strategy. It is emphasized that hypnosis promotes a milieuin which effective strategies can be integrated and the hypnotictechniques can give patients the needed impetus to recognize theirability to regain control.
McKechnie(1975) experimented with relaxation as a treatment forphantom limb pain. McKechnie reports observing relief from phantomlimb pain in a young male adult patient with a nine-year history ofsuch pain. Relief occurred during and after relaxation exercisesfocused on the phantom limb and was facilitated by practice.Six-month follow-up revealed continued relief. The relaxationtechnique is related to the hypnosis treatment by use the use of mindand body to control the pain in both techniques.
Although many studies point to cortical reorganization of theneurons as the result of this phantom limb pain, we have still notfound a major way to extinguish this pain. In addition to corticalreorganization, scientists have studied psychosocial factors andstress as related to phantom limb pain. In the future, methodsdesigned to alter cortical reorganization should be examined alongwith stress releasers, relaxation techniques, and pharmaceuticalagents for their efficacy in the treatment of phantom limb pain.
References
Arena, J., Sherman, R., Bruno, G. & Smith J. (1990). Therelationship between situation stress and phantom limb pain:Cross-lagged correlation data from six month pain logs. Journal ofPsychosomatic Research, 34(1), 71-77.
Birbaumer, N., Lutzenberger, W., Montoya, P. & Larbig, W.(1997). Effects of regional anesthesia on phantom limb pain aremirrored in changes in cortical reorganization. Journal ofNeuroscience, 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 corticalreorganization following arm amputation. Journal of Nature,375(6531), 482-484.
McKechnie, R. (1975). Relief from phantom limb pain by relaxationexercises. Journal of Behavior Therapy and ExperimentalPsychiatry, 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 andtemperature biofeedback. American Journal of Clinical Biofeedback,5(2), 150-153.
Wain, H. (1986). Pain control with hypnosis in consultation andliaison psychiatry. Psychiatric Annuals, 16(2), 106-109.
Sussman, V. (October 1995). The route of phantom pain. U.S.News & World Report, 76-78.