Chronic phantom sensations, phantom pain, residual limb pain, and other regional pain after lower limb amputation

OBJECTIVES: To determine the characteristics of phantom limb sensation, phantom limb pain, and residual limb pain, and to evaluate pain-related disability associated with phantom limb pain. DESIGN: Retrospective, cross-sectional survey. Six or more months after lower limb amputation, participants (n = 255) completed an amputation pain questionnaire that included several standardized pain measures. SETTING: Community-based survey from clinical databases. PARTICIPANTS: A community-based sample of persons with lower limb amputations. MAIN OUTCOME MEASURES: Frequency, duration, intensity, and quality of phantom limb and residual limb pain, and pain-related disability as measured by the Chronic Pain Grade. RESULTS: Of the respondents, 79% reported phantom limb sensations, 72% reported phantom limb pain, and 74% reported residual limb pain. Many described their phantom limb and residual limb pain as episodic and not particularly bothersome. Most participants with phantom limb pain were classified into the two low pain-related disability categories: grade I, low disability/low pain intensity (47%) or grade II, low disability/high pain intensity (28%). Many participants reported having pain in other anatomic locations, including the back (52%). CONCLUSIONS: Phantom limb and residual limb pain are common after a lower limb amputation. For most, the pain is episodic and not particularly disabling. However, for a notable subset, the pain may be quite disabling. Pain after amputation should be viewed from a broad perspective that considers other anatomic sites as well as the impact of pain on functioning.     

Methadone for phantom limb pain

OBJECTIVE: The objective of this case series was to determine if severe phantom limb pain could be reduced with oral methadone. DESIGN: Four cases of phantom limb pain refractory to multiple treatment modalities were treated with oral methadone. SETTING: Pain clinic at a major university medical center. PATIENTS: Four patients with severe, intractable phantom limb pain. INTERVENTION: Oral methadone was administered, starting with a low dose of 2 to 5 mg twice a day or three times a day and slowly titrated upward to achieve pain relief. OUTCOME MEASURES: Repeated administration of a visual analog scale for pain. RESULTS AND CONCLUSIONS: Administration of oral methadone may be of value in the treatment of phantom limb pain; controlled clinical trials would be appropriate to verify this observation.     

Phantom limb, phantom pain and stump pain in amputees during the first 6 months following limb amputation

The incidence and clinical picture of non-painful and painful phantom limb sensations as well as stump pain was studied in 58 patients 8 days and 6 months after limb amputation. The incidence of non-painful phantom limb, phantom pain and stump pain 8 days after surgery was 84, 72 and 57%, respectively. Six months after amputation the corresponding figures were 90, 67 and 22%, respectively. Kinaesthetic sensations (feeling of length, volume or other spatial sensation of the affected limb) were present in 85% of the patients with phantom limb both immediately after surgery and 6 months later. However, 30% noticed a clear shortening of the phantom during the follow-up period; this was usually among patients with no phantom pain. Phantom pain was significantly more frequent in patients with pain in the limb the day before amputation than in those without preoperative limb pain. Of the 67% having some phantom pain at the latest interview 50% reported that pains were decreasing. Four patients (8%), however, reported that phantom pains were worse 6 months after amputation than originally. During the follow-up period the localization of phantom pains shifted from a proximal and distal distribution to a more distal localization. While knifelike, sticking phantom pains were most common immediately after surgery, squeezing or burning types of phantom pain were usually reported later in the course. Possible mechanisms for the present findings either in periphery, spinal cord or in the brain are discussed.     

The causes and treatments of phantom limb pain

Almost all patients who undergo amputation suffer 'phantom sensations', a sensory perception of the missing limb, possibly caused by a neural imprint or memory of the limb within the brain. The patient may experience abnormal kinaesthetic sensation, such as the feeling that the limb is in an abnormal position. Perceived changes in length, size or temperature of the limb are also common. Some of these people will go on to develop phantom limb pain (PLP). Appropriate aggressive pain management is required immediately postamputation in an attempt to avoid chronic PLP.     

Phantom pain in bilateral upper limb amputation

Purpose.?To alert health professionals on presence and extent of phantom pain and sensation following bilateral upper limb amputation.

Methods.?Of a total of 140 war-related bilateral upper limb amputees in Iran, 103 subjects were thoroughly examined in this cross-sectional study by a physical medicine specialist. The patients were questioned for the presence of phantom pain and sensations, and frequency and intensity of the feeling were recorded.

Results.?At 17.1 ± 6.1 years after injury, 82.0% of the 103 amputees suffered from phantom sensation, including varying degrees of phantom limb pain in 53.9% of stumps. Phantom phenomena had a higher frequency in the right extremities, but this was not statistically significant (p > 0.01). Of those amputees who had phantom pain or sensation, 51.2% reported that they ‘always’ had phantom limb sensation; and approximately one-fourth of the subjects (24.6%) ‘always’ had phantom pain. Among the stumps who reported phantom pain (N = 112), the pain was excruciating (38.5%), distressing (34.9%) or discomforting (25.6%). A significant statistical relation between phantom limb sensation and level of amputation was observed (p < 0.01).

Conclusion.?At this time there is no healing for phantom pain; medical and surgical modalities only bring temporary relief, and less than 1% of the respondents achieve permanent relief through different treatment methods.     

Psychological distress in amputees with phantom limb pain.

Research suggesting that psychological factors play a role in phantom limb pain abounds in the literature. Despite recent research suggesting that these factors exacerbate rather than cause phantom limb pain, clinicians still frequently use personality as a rationale to explain amputees' phantom limb pain. The present study aimed to examine psychological distress in a working-age population of amputees not specifically seeking help for their pain. The study was conducted in two phases. Phase 1 included 315 amputees who completed the General Health Questionnaire (GHQ). Phase 2 included a subset of the original sample who completed the Beck Depression Inventory (BDI). In Phase 1, although over 50% of the sample reported GHQ scores over the threshold used to detect "caseness," this was not related to phantom limb pain. In Phase 2 of the study, only 15% of the sample reported moderate to severe symptoms of depression. Only 4% of the variance in phantom limb pain was accounted for using the overall BDI score. When BDI items were examined individually within regression models, a number significantly predicted phantom limb pain. However, the items most related to phantom limb pain were those involved in "performance difficulties" rather than "negative affect." The present study suggests that negative affect in amputees may be related to disability rather than pain.     

Phantom limb pain during peridural anaesthesia

We report the occurrence of severe phantom leg pain during peridural anaesthesia. The patient had no preoperative pain complaints or neurological deficits and was scheduled for surgical removal of an osteosynthesis plate from his otherwise intact femur.The pain developed parallel with the appearance of phantom sensation during peridural anaesthesia. It was independent of surgical stimulation and vanished towards the end of the operation. Phantom limb pain disappeared completely with dissipation of regional blockade.Some of the possible mechanisms of painless and painful phantoms are discussed.We suggest that investigation of similar cases may help in elucidating phantom limb pain following irreversible pathological deafferentation.     

Disappearance of phantom pain after focal brain infarction

A patient with hemiplegia and hemihypoesthesia is presented in whom preexisting phantom limb pain disappeared with the appearance of a stroke localized by CT scan to the posterior internal capsule. Differentiation between the cutaneous sensation and the sensation of phantom limb pain that appeared later seems to support the assumed existence of a polysynaptic sensory pathway that conveys the sensations of deafferentation.     

Electroconvulsive therapy for phantom limb pain

Phantom limb pain is common in amputees. Although several treatments are available, a significant number of patients are refractory. Electroconvulsive therapy (ECT), which is usually given to patients with psychiatric disorders such as major depression, has shown efficacy in patients with a variety of pain syndromes occurring along with depression. Two patients are described herein with severe phantom limb pain refractory to multiple therapies, without concurrent psychiatric disorder, who received ECT. Both patients enjoyed substantial pain relief. In one case, phantom pain was still in remission 3.5 years after ECT. It is concluded that phantom limb patients who are refractory to multiple therapies may respond to ECT.     

Carbamazepine in the treatment of phantom limb pain

The successful use of carbamazepine in treating a case of severe phantom limb pain prompted me to review this condition and its experiential treatment with carbamazepine, as well as the drug's possible mechanism of action on phantom limb pain. Experience to date indicates the need for controlled double-blind crossover studies to test the therapeutic validity of carbamazepine.     

Phantom pain and phantom sensations in upper limb amputees: an epidemiological study

Phantom pain in subjects with an amputated limb is a well-known problem. However, estimates of the prevalence of phantom pain differ considerably in the literature. Various factors associated with phantom pain have been described including pain before the amputation, gender, dominance, and time elapsed since the amputation. The purposes of this study were to determine prevalence and factors associated with phantom pain and phantom sensations in upper limb amputees in The Netherlands. Additionally, the relationship between phantom pain, phantom sensations and prosthesis use in upper limb amputees was investigated. One hundred twenty-four upper limb amputees participated in this study. Subjects were asked to fill out a self-developed questionnaire scoring the following items: date, side, level, and reason of amputation, duration of experienced pain before amputation, frequencies with which phantom sensations, phantom pain, and stump pain are experienced, amount of trouble and suffering experienced, respectively, related to these sensations, type of phantom sensations, medical treatment received for phantom pain and/or stump pain, and the effects of the treatment, self medication, and prosthesis use. The response rate was 80%. The prevalence of phantom pain was 51%, of phantom sensations 76% and of stump pain 49%; 48% of the subjects experienced phantom pain a few times per day or more; 64% experienced moderate to very much suffering from the phantom pain. A significant association was found between phantom pain and phantom sensations (relative risk 11.3) and between phantom pain and stump pain (relative risk 1.9). No other factors associated with phantom pain or phantom sensations could be determined. Only four patients received medical treatment for their phantom pain. Phantom pain is a common problem in upper limb amputees that causes considerable suffering for the subjects involved. Only a minority of subjects are treated for phantom pain. Further research is needed to determine factors associated with phantom pain.     

Immediate response of phantom limb pain to calcitonin

We applied calcitonin in a single-shot treatment to 10 patients with persistent or acute phantom limb pain. Nine patients responded immediately and noted a clear analgesic effect. In contrast a group of non-phantom pain patients of heterogeneous composition did not respond at all, except 1 patient with chronic stump pain. We believe that this could be an exciting new approach to the treatment of phantom limb pain.     

Variation in phantom limb pain: results of a diary study.

Amputees experience multiple, complex problems in addition to phantom limb pain. Although studies have yielded useful data on the relationship between phantom limb pain and other variables, this research generally has evaluated only one aspect of phantom limb pain and measured it at only one time point. The present study examined ongoing phantom limb pain and associated factors prospectively through the use of hourly pain diaries that are completed over a 7-day period. The sample comprised a subset of 89 lower limb amputees taking part in a longitudinal research study. Subjects had a mean age of 46.1 years. Forty-seven per cent were female, 53% male. Subjects completed a Pain/Coping Diary that measured phantom limb pain intensity, activity levels, medication use, and alcohol use on an hourly basis over a 7-day period. It also asked subjects to list the coping strategies used on the same hourly basis over a 7-day period. The diaries highlighted the following: Phantom limb pain appears to be episodic in nature and there is great variation in its intensity. Amputees use a limited repertoire of coping strategies to deal with episodes of phantom limb pain, and of those strategies that are used, few reduce the level of pain. This variability in phantom limb pain has important implications for those involved in the care of amputees as a report of phantom limb pain at a given point in time may not reflect the amputee's overall pain experience.     

Cognitive-emotional sensitization contributes to wind-up-like pain in phantom limb pain patients

Peripheral mechanisms are known to play a role in phantom pain following limb amputation, and more recently it has been suggested that central mechanisms may also be of importance. Some patients seem to have a psychological sensitivity that predisposes them to react with pain catastrophizing after amputation of a limb, and this coping style may contribute to increased facilitation, impaired modulation of nociceptive signals, or both. To investigate how pain catastrophizing, independently of anxiety and depression, may contribute to phantom limb pain and to alterations in pain processing twenty-four upper-limb amputees with various levels of phantom limb pain were included in the study. Patients’ level of pain catastrophizing, anxiety and depression was assessed and they went through quantitative sensory testing (QST) of thresholds (mechanical and thermal) and wind-up-like pain (brush and pinprick). Catastrophizing accounted for 35% of the variance in phantom limb pain (p = 0.001) independently of anxiety and depression. Catastrophizing was also positively associated with wind-up-like pain in non-medicated patients (p = 0.015), but not to pain thresholds. These findings suggest that cognitive-emotional sensitization contributes to the altered nociceptive processing seen in phantom limb pain patients. The possible interactions between pain catastrophizing, wind-up-like pain, and peripheral input in generating and maintaining phantom limb pain are discussed.     

Peripheral nervous system origin of phantom limb pain

Nearly all amputees continue to feel their missing limb as if it still existed, and many experience chronic phantom limb pain (PLP). What is the origin of these sensations? There is currently a broad consensus among investigators that PLP is a top-down phenomenon, triggered by loss of sensory input and caused by maladaptive cortical plasticity. We tested the alternative hypothesis that PLP is primarily a bottom-up process, due not to the loss of input but rather to exaggerated input, generated ectopically in axotomized primary afferent neurons in the dorsal root ganglia (DRGs) that used to innervate the limb. In 31 amputees, the local anesthetic lidocaine was applied intrathecally and/or to the DRG surface (intraforaminal epidural block). This rapidly and reversibly extinguished PLP and also nonpainful phantom limb sensation (npPLS). Control injections were ineffective. For intraforaminal block, the effect was topographically appropriate. The suppression of PLP and npPLS could also be demonstrated using dilute lidocaine concentrations that are sufficient to suppress DRG ectopia but not to block the propagation of impulses generated further distally in the nerve. PLP is driven primarily by activity generated within the DRG. We recommend the DRG as a target for treatment of PLP and perhaps also other types of regional neuropathic pain.     

Illusory movements of the paralyzed limb restore motor cortex activity

In humans, limb amputation or brachial plexus avulsion (BPA) often results in phantom pain sensation. Actively observing movements made by a substitute of the injured limb can reduce phantom pain, Proc. R. Soc. London B Biol. Sci. 263, 377-386). The neural basis of phantom limb sensation and its amelioration remains unclear. Here, we studied the effects of visuomotor training on motor cortex (M1) activity in three patients with BPA. Functional magnetic resonance imaging scans were obtained before and after an 8-week training program during which patients learned to match voluntary "movements" of the phantom limb with prerecorded movements of a virtual hand. Before training, phantom limb movements activated the contralateral premotor cortex. After training, two subjects showed increased activity in the contralateral primary motor area. This change was paralleled by a significant reduction in phantom pain. The third subject showed no increase in motor cortex activity and no improvement in phantom pain. We suggest that successful visuomotor training restores a coherent body image in the M1 region and, as a result, directly affects the experience of phantom pain sensation. Artificial visual feedback on the movements of the phantom limb may thus "fool" the brain and reestablish the original hand/arm cortical representation.     

Amputation and phantom limb pain: a pain-prevention model.

Within the figure of more than 200,000 surgical amputations performed in the United States each year lies another--70% of patients experience phantom limb pain after the procedure, and 50% still experience phantom pain 5 years after surgery. Patients describe burning, stabbing, twisting, cramping, or throbbing pains in the missing part. Adding to the patient's and the anesthesia professional's conundrum has been the lack of a simple model that tissue injury produces pain. The patient with a surgical amputation who experiences phantom limb pain can have several sources for discomfort including problems from the original tissue injury or from pathology, e.g., scarring or continued cellular dysfunction resulting from diabetes, ischemia, or infection. Suboptimal prosthesis fit and tissues and joints connected to the affected part can continue to generate pain long after surgical wound healing. In addition, nonaffected tissues and joints now made to carry extra loads as a result of altered gait and balance can sustain collateral stress and damage and produce nociception. In addition to this series of problems, amputee patients remain susceptible to the pain problems experienced by the general population. There is a positive correlation between a painful limb before amputation and experiencing chronic phantom limb pain. Authors have described patients with preamputation pain who benefited from effective preemptive analgesia and experienced less phantom limb pain. CRNAs can have a significant role in providing anesthesia and analgesia services to these patients and can begin to think in terms of preventing lifelong pain.     

Pain in traumatic upper limb amputees in Sierra Leone

Data on 40 upper limb amputees (11 bilateral) with regard to stump pain, phantom sensation and phantom pain is presented. All the patients lost their limbs as a result of violent injuries intended to terrorise the population and were assessed 10-48 months after the injury. All amputees reported stump pain in the month prior to interview and ten of the 11 bilateral amputees had bilateral pain. Phantom sensation was common (92.5%), but phantom pain was only present in 32.5% of amputees. Problems in translation and explanation may have influenced the low incidence of phantom pain and high incidence of stump pain. In the bilateral amputees phantom sensation, phantom pain and telescoping all showed bilateral concordance, whereas stump pain and neuromas did not show concordance. About half the subjects (56%) had lost their limb at the time of injury (primary) while the remainder had an injury, then a subsequent amputation in hospital (secondary). There was no association between the incidence of phantom pain and amputation irrespective of being primary or secondary.     

Increased phantom limb painas an initial symptom of spinal neoplasia

Phantom limb pain is a common sequela of amputation. Studies suggest that over time,there is a decrease in frequency and intensity of phantom pain. Persistently increased phantom pain has been seen in benign lesions affecting the peripheral and central nervous system. We present a 74-year- old woman who had a left above-knee amputation for leiomyosarcoma of the foot 24 years previously. She had been free of disease and ambulated independently until 1 month before hospitalization, when she noted increasing pain in her phantom foot. At the time of admission, she had developed increasing low back pain and was diagnosed with adenocarcinoma of unknown primary. Work-up confirmed involvement of the L4 vertebral body with epidural and paraspinal disease. We believe this is the first reported case of worsening phantom limb pain resulting from a spinal metastasis. We review the literature on the potential implications of increased phantom pain.