Phantom limb pain and related disorders

Prevalence and factors associated with psychological morbidity, phantom limb Pain in lower limb amputees

BACKGROUND

Lower limb amputation can lead to psychological problems.There is a lack of data to evaluate the psychological problems and associated factors in lower limb amputees.

AIM

Prevalence and factors associated with psychological disorder and phantom limb pain in lower limb amputees METHODS: It was a cross-sectional study with a consecutive sampling technique. Patients were assessed on the Hospital Anxiety and Depression Scale (HADS) for the presence of depression and anxiety disorder. DSM-5 diagnostic criteria for substance use disorder were used, andphantom limb pain was diagnosed as defined by Pare.

RESULTS

103 patients were included in the present study with a mean age of37.7 ± 14.5 yrs. The majorityof patients were males (87.4 %), married (69.9 %), on paid employment (95.1 %), and were of middle socioeconomic status (83.5 %). Most of the patients presented with roadside accident injuries (83.5 %)and had below-knee amputation (58.3 %). As per DSM-5, 38.8 % had a substance use disorder, out of which 35.9 % and 24.3 % had alcohol and tobacco use disorders, respectively. On HADS, 48.5 % had a presence of depressive disorder, and 30.1 % had anxiety disorder. The majority of patients (97.1 %) had phantom limb pain. Those from rural areas reported significantly more frequency of anxiety (x2-5.501; p-0.019) and depressive disorder (x2-7.009; p-0.008). Lower incomehad a significant positive association with depression (r-0.228; p-0.021) and phantom limb pain (U-22.500; p-0.008).

CONCLUSION

The prevalence of psychiatric morbidity in lower-limb amputeeswas very high. The most common psychological morbidity was depression,followed by anxiety disorder and substance use disorders.Our findings reflect that we would benefit by including mental health professionals asintegral members of the multidisciplinary team to do an early psychological assessment and intervention, which would help prevent psychological illnesses and improve quality of life.

Comparative Effects of Interventions on Phantom Limb Pain: A Network Meta-Analysis

BACKGROUND

Phantom limb pain (PLP) is a common type of chronic pain that occurs after limb amputation. Many treatment approaches are available; however, the treatment of PLP is still a challenge. This study aimed to quantify and rank the efficacy of interventions for phantom limb pain.

METHODS

A comprehensive literature search was performed using the databases of PubMed, MEDLINE, Embase, Web of Science, and Cochrane. A network meta-analysis was applied to formulate direct and indirect comparisons among interventions for PLP.

RESULTS

Twenty-two studies comprising 662 patients and 13 different interventions were included in this study. The mirror therapy (MT) (-1.00; 95% confidence interval, -1.94 to -0.07) and MT + phantom exercise (PE) (-6.05; 95% confidence interval, -8.29 to -3.81) group presented significantly lower pain intensity compared with placebo. In SUCRA (surface under the cumulative ranking curve) analysis, the MT+PE and neuromodulation techniques groups had the highest SUCRA value (81.2).

CONCLUSIONS

Our results suggest that MT is the most optimal treatment for PLP, and a combination of therapies would enhance the therapeutic effect.

Transcranial direct current stimulation in the management of phantom limb pain: a systematic review of randomized controlled trials

INTRODUCTION

Phantom limb pain (PLP) after amputation is a frequent entity that conditions the life of those who suffer it. Current treatment methods are not sufficiently effective for PLP management. We aim to analyze the clinical application of transcranial direct current (tDCS) in people with amputation suffering from PLP.

EVIDENCE ACQUISITION

The following databases were consulted in September 2021: MEDLINE, EMBASE, The Web of Science, PEDro, SCOPUS and SciELO. Randomized controlled trials investigating the use of tDCS in people with amputation undergoing PLP were selected. Demographic data, type and cause of amputation, time since amputation, stimulation parameters, and outcomes were extracted.

EVIDENCE SYNTHESIS

Six articles were included in this review (seven studies were considered because one study performed two individual protocols). All included studies evaluated PLP; six evaluated the phantom limb sensations (PLS) and two evaluated the psychiatric disorders. In all included studies the intensity and frequency of PLP was reduced, in three PLS were reduced, and in none study psychiatric symptoms were modified.

CONCLUSIONS

Anodic tDCS over the contralateral M1 to the affected limb, with an intensity of 1-2 mA, for 15-20 minutes seems to significantly reduce PLP in people with amputation. Single-session treatment could modify PLP intensity for hours, and multi-session treatment could modify PLP for months. Limited evidence suggests that PLS and psychiatric disorders should be treated with different PLP electrode placements. Further studies with larger sample size and longer follow-up times are needed to establish the priority of tDCS application in the PLP management.

Management of Phantom Limb Pain through Thalamotomy of the Centro-Median Nucleus

Background: Phantom limb syndrome is defined as the perception of intense pain or other sensations that are secondary to a neural lesion in a limb that does not exist. It can be treated using pharmacological and surgical interventions. Most medications are prescribed to improve patients’ lives; however, the response rate is low. In this case report, we present a case of phantom limb syndrome in a 42-year-old female with a history of transradial amputation of the left thoracic limb due to an accidental compression one year before. The patient underwent placement of a deep brain stimulator at the ventral posteromedial nucleus (VPM) on the right side and removal secondary to loss of battery. The patient continued to have a burning pain throughout the limb with a sensation of still having the limb, which was subsequently diagnosed as phantom limb syndrome. After a thorough discussion with the patient, a right stereotactic centro-median thalamotomy was offered. An immediate response was reported with a reduction in pain severity on the visual analogue scale (VAS) from a value of 9–10 preoperative to a value of 2 postoperative, with no postoperative complications. Although phantom limb pain is one of the most difficult to treat conditions, centro-median thalamotomy may provide an effective stereotactic treatment procedure with adequate outcomes.

Mirror therapy for phantom limb pain in moderate intellectual disability. A case report

BACKGROUND

Phantom limb pain (PLP) is a common problem after limb amputation. There is mounting evidence supporting the use of mirror therapy (MT) in the treatment of individuals with PLP. However, there is no research studying the effects of MT on PLP in individuals with intellectual developmental disorders (IDD). The aim of this study was to increase our understanding of MT when used with adults with IDD and PLP through a case study approach.

METHODS

Here, we describe the use of MT with a 53-year-old female with moderate IDD and PLP, related to her left leg being amputated after ulcer complications. The study followed an A-B-A-B design (baseline-treatment-withdrawal of treatment-re-introduction of treatment), lasting 2 years, which included a long-term follow-up.

RESULTS

The data showed that the PLP sensation decreased after the MT treatment, with a raw change of 3.92 points and a 48% decrease in mean pain intensity ratings from pre- to post-treatment.

CONCLUSIONS

This is a unique case-report on the use of MT with an individual with IDD suffering from PLP. The findings show that MT helped to significantly reduce the intensity of the PLP in this patient.

SIGNIFICANCE

This is a case-report that illustrates how mirror therapy can be applied to people with intellectual developmental disorders and phantom limb pain. The results showed that phantom limb pain decreased after the mirror therapy, with a raw change of 3,92 points and a percent change of 48%.

Neurophysiological models of phantom limb pain: what can be learnt

Phantom Limb Pain (PLP) is a dysesthesic painful sensations perceived in the lost limb, resulting from complex interactions between structural and functional nervous systems changes. We analyze its main pathogenetic models and speculate on candidate therapeutic targets. The neuroma model considers PLP to arise from spontaneous activity of residual limb injured axons. Other peripheral-origin models attribute PLP to damage of somatosensory receptors or vascular changes. According to the cortical remapping model, the loss of bidirectional nervous flow and the need to enhance alternative functions trigger reorganization and arm and face skin afferents "invade" the hand territory. On the contrary, the persistent representation model suggests that continued inputs preserve the lost limb representation and that, instead to a shrinkage, PLP is associated with larger representation and stronger cortical activity. In the neuromatrix model, the mismatch between body representation, which remains intact despite limb amputation, and real body appearance generates pain. Another hypothesis is that proprioceptive memories associate specific limb positions with pre-amputation pain and may be recalled by those positions. Finally, the stochastic entanglement model offers a direct relationship between sensorimotor neural reorganization and pain. Amputation disrupts motor and somatosensory circuits, allowing for maladaptive wiring with pain circuits and causing pain without nociception. Relief of PLP depends solely on motor and somatosensory circuitry engagement, making anthropomorphic visual feedback dispensable. Existing and apparently contradicting theories might not be mutually exclusive. All of them involve several intertwined potential mechanisms by which replacing the amputated limb by an artificial one could counteract PLP.

Neuromodulation Techniques in Phantom Limb Pain: A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the effects of neuromodulation techniques in adults with phantom limb pain (PLP).

METHODS

A systematic search was performed, comprising randomized controlled trials (RCTs) and quasi-experimental (QE) studies that were published from database inception to February 2019 and that measured the effects of neuromodulation in adults with PLP. Hedge's g effect size (ES) and 95% confidence intervals were calculated, and random-effects meta-analyses were performed.

RESULTS

Fourteen studies (nine RCTs and five QE noncontrolled studies) were included. The meta-analysis of RCTs showed significant effects for i) excitatory primary motor cortex (M1) stimulation in reducing pain after stimulation (ES = -1.36, 95% confidence interval [CI] = -2.26 to -0.45); ii) anodal M1 transcranial direct current stimulation (tDCS) in lowering pain after stimulation (ES = -1.50, 95% CI = -2.05 to 0.95), and one-week follow-up (ES = -1.04, 95% CI = -1.64 to 0.45). The meta-analysis of noncontrolled QE studies demonstrated a high rate of pain reduction after stimulation with transcutaneous electrical nerve stimulation (rate = 67%, 95% CI = 60% to 73%) and at one-year follow-up with deep brain stimulation (rate = 73%, 95% CI = 63% to 82%).

CONCLUSIONS

The evidence from RCTs suggests that excitatory M1 stimulation-specifically, anodal M1 tDCS-has a significant short-term effect in reducing pain scale scores in PLP. Various neuromodulation techniques appear to have a significant and positive impact on PLP, but due to the limited amount of data, it is not possible to draw more definite conclusions.

Role of Potassium Ions Quantum Tunneling in the Pathophysiology of Phantom Limb Pain

(1) Background: multiple theories were proposed to explain the phenomenon of phantom limb pain (PLP). Nevertheless, the phenomenon is still shrouded in mystery. The aim of this study is to explore the phenomenon from a new perspective, where quantum tunneling of ions, a promising field in medical practice, might play a major role. (2) Methods: investigators designed a quantum mathematical model based on the Schrödinger equation to examine the probability of potassium ions quantum tunneling through closed membrane potassium channels to the inside of phantom axons, leading to the generation of action potential. (3) Results: the model suggests that the probability of action potential induction at a certain region of the membrane of phantom neurons, when a neuron of the stump area is stimulated over 1 mm² surface area of the membrane available for tunneling is 1.04 × 10⁻². Furthermore, upon considering two probabilities of potassium channelopathies, one that decreased the energy of the barrier by 25% and another one by 50%, the tunneling probability became 1.22 × 10⁻⁸ and 3.86 × 10⁻⁴, respectively. (4) Conclusion: quantum models of potassium ions can provide a reliable theoretical hypothesis to unveil part of the ambiguity behind PLP.

A Pre-clinical Study of the Response Threshold of Intact and Transected Nerves to Stimulation by Transcutaneous Intense Focused Ultrasound

We used diagnostic ultrasound imaging to guide individual bursts (0.1 s) of 2 MHz intense focused ultrasound (iFU) to determine the sensitivity of intact and transected nerves. We found that all nerves had greater sensitivity to iFU stimulation than surrounding muscle. Intact nerves from healthy volunteers had less sensitivity to iFU stimulation (272 ± 35 W/cm² [median ± standard error]) than transected nerves (19 ± 37 W/cm²). Intact, contralateral nerves of amputees dichotomized naturally into two groups-one very sensitive to iFU stimulation (6 ± 2 W/cm²) and one relatively insensitive (539 ± 19 W/cm²), compared with the intact nerves of healthy volunteers. Our study demonstrates the ability of iFU under ultrasound image guidance to stimulate deep, intact and transected peripheral nerves. It also highlights differences in the receptivity to ultrasound stimulation of the peripheral nerves of amputees versus healthy volunteers.

Real-time Video Projection in an MRI for Characterization of Neural Correlates Associated with Mirror Therapy for Phantom Limb Pain

Mirror therapy (MT) has been proposed as an effective rehabilitative strategy to alleviate pain symptoms in amputees with phantom limb pain (PLP). However, establishing the neural correlates associated with MT therapy have been challenging given that it is difficult to administer the therapy effectively within a magnetic resonance imaging (MRI) scanner environment. To characterize the functional organization of cortical regions associated with this rehabilitative strategy, we have developed a combined behavioral and functional neuroimaging protocol that can be applied in participants with a leg amputation. This novel approach allows participants to undergo MT within the MRI scanner environment by viewing real-time video images captured by a camera. The images are viewed by the participant through a system of mirrors and a monitor that the participant views while lying on the scanner bed. In this manner, functional changes in cortical areas of interest (e.g., sensorimotor cortex) can be characterized in response to the direct application of MT.

Intense Focused Ultrasound Preferentially Stimulates Transected Nerves Within Residual Limbs: Pilot Study

Objective

Identifying pain generators in tissue deep in the skin can require uncomfortable, complicated, and invasive tests. We describe pilot studies testing the hypothesis that ultrasound image-guided, intense focused ultrasound (ig-iFU) can noninvasively and differentially stimulate the end of transected nerves in the residual limbs of amputee patients.

Design

We applied iFU to the transected nerve ending as individual pulses with a length of 0.1 seconds using a carrier frequency of 2.0 MHz. After targeting, we gradually increased the iFU intensity to reach consistent patient-reported stimulation of the transected nerve ending. We also stimulated the proximal nerve, tissue near the nerve ending, and the intact contralateral nerve. We described the resulting sensations and correlated the results of the study participant's pre-iFU study responses to phantom and residual limb pain questionnaires.

Results

iFU spatial and temporal average intensity values between 16 W/cm2 and 433 W/cm2 that were applied to the transected nerve ending and proximal nerve elicited sensations, including phantom limb sensations, while the same intensity applied to control tissue centimeters away from the nerve ending, or to the intact nerve on the contralateral limb, did not. Two out of 11 study participants reported only mild and transient pain created by iFU stimulation. Successful iFU intensity values correlated with neither phantom nor residual limb pain scores.

Conclusions

Transected nerves had greater sensitivity to iFU stimulation than ipsilateral and contralateral control tissue, including intact nerve. These results support the view that ig-iFU may one day help physicians identify deep, tender tissue in patients who report experiencing pain.

A comparison of the effects of mirror therapy and phantom exercises on phantom limb pain

Background/aim

Although mirror therapy (MT) and phantom exercises (PE) have been shown to reduce pain, the efficacy of these methods in terms of pain, quality of life (QoL), and psychological status (PS) has not been investigated and compared to date. The aim of this study was to determine whether there is any difference between MT and PE in the treatment of phantom limb pain (PLP).

Materials and methods

Forty unilateral transtibial amputees (aged 18–45 years) participated in this study. The subjects were randomly divided into ‘MT group’ and ‘PE group’. QoL was assessed using Short-Form 36 (SF-36), psychological status using the Beck depression inventory (BDI), and pain intensity using a visual analog scale (VAS), before and at the end of the program, and on the 3rd and 6th months thereafter.

Results

All assessments for all parameters improved significantly in both groups (P < 0.05). Comparison of the two groups revealed a significant difference in changes for VAS and BDI in all measurements, and in pre- and posttreatment scores for all SF-36 parameters (except for Role-Emotional) in favor of the MT group (P < 0.05).

Conclusion

While pain intensity decreased and QoL and PS improved in both the MT and PE groups, these improvements were greater in the MT group.

The Stochastic Entanglement and Phantom Motor Execution Hypotheses: A Theoretical Framework for the Origin and Treatment of Phantom Limb Pain

Phantom limb pain (PLP) is a debilitating condition common after amputation that can considerably hinder patients' quality of life. Several treatments have reported promising results in alleviating PLP. However, clinical evaluations are usually performed in small cohorts and rigorous clinical trials are scarce. In addition, the underlying mechanisms by which novel interventions alleviate PLP are often unclear, potentially because the condition itself is poorly understood. This article presents a theoretical framework of PLP that can be used as groundwork for hypotheses of novel treatments. Current hypotheses on the origins of PLP are discussed in relation to available clinical findings. Stochastic entanglement of the pain neurosignature, or connectome, with impaired sensorimotor circuitry is proposed as an alternative hypothesis for the genesis of PLP, and the implications and predictions this hypothesis entails are examined. In addition, I present a hypothesis for the working mechanism of Phantom Motor Execution (PME) as a treatment of PLP, along with its relation to the aforementioned stochastic entanglement hypothesis, which deals with PLP's incipience. PME aims to reactivate the original central and peripheral circuitry involved in motor control of the missing limb, along with increasing dexterity of stump muscles. The PME hypothesis entails that training of phantom movements induces gradual neural changes similar to those of perfecting a motor skill, and these purposefully induced neural changes disentangle pain processing circuitry by competitive plasticity. This is a testable hypothesis that can be examined by brain imaging and behavioral studies on subjects undergoing PME treatment. The proposed stochastic entanglement hypothesis of PLP can be generalized to neuropathic pain due to sensorimotor impairment, and can be used to design suitable therapeutic treatments.

A review of current theories and treatments for phantom limb pain

Following amputation, most amputees still report feeling the missing limb and often describe these feelings as excruciatingly painful. Phantom limb sensations (PLS) are useful while controlling a prosthesis; however, phantom limb pain (PLP) is a debilitating condition that drastically hinders quality of life. Although such experiences have been reported since the early 16th century, the etiology remains unknown. Debate continues regarding the roles of the central and peripheral nervous systems. Currently, the most posited mechanistic theories rely on neuronal network reorganization; however, greater consideration should be given to the role of the dorsal root ganglion within the peripheral nervous system. This Review provides an overview of the proposed mechanistic theories as well as an overview of various treatments for PLP.

A review of the management of phantom limb pain: challenges and solutions

BACKGROUND

Phantom limb pain (PLP) occurs in 50% and 80% of amputees. Although it is often classified as a neuropathic pain, few of the large-scale trials of treatments for neuropathic pain included sufficient numbers of PLP sufferers to have confidence that they are effective in this condition. Many therapies have been administered to amputees with PLP over the years; however, as of yet, there appears to be no first-line treatment.

OBJECTIVES

To comprehensively review the literature on treatment modalities for PLP and to identify the challenges currently faced by clinicians dealing with this pain.

METHOD

MEDLINE, EMBASE, CINAHL, British Nursing Index, Cochrane and psycINFO databases were searched using "Phantom limb" initially as a MeSH term to identify treatments that had been tried. Then, a secondary search combining phantom limb with each treatment was performed to find papers specific to each therapy. Each paper was assessed for its research strength using the GRADE system.

RESULTS

Thirty-eight therapies were identified. Overall, the quality of evidence was low. There was one high-quality study which used repetitive transcutaneous magnetic stimulation and found a statistical reduction in pain at day 15 but no difference at day 30. Significant results from single studies of moderate level quality were available for gabapentin, ketamine and morphine; however, there was a risk of bias in these papers. Mirror therapy and associated techniques were assessed through two systematic reviews, which conclude that there is insufficient evidence to support their use.

CONCLUSION

No decisions can be made for the first-line management of PLP, as the level of evidence is too low. Robust studies on homogeneous populations, an understanding of what amputees consider a meaningful reduction in PLP and agreement of whether pain intensity is the legitimate therapeutic target are urgently required.

[Psychotherapies for the Treatment of Phantom Limb Pain]

INTRODUCTION

The phantom limb pain has been described as a condition in which patients experience a feeling of itching, spasm or pain in a limb or body part that has been previously amputated. Such pain can be induced by a conflict between the representation of the visual and proprioceptive feedback of the previously healthy limb. The phantom limb pain occurs in at least 42 to 90% of amputees. Regular drug treatment of phantom limb pain is almost never effective.

METHODS

A systematic review of the literature was conducted in Medline and Cochrane using the MESH terms "phantom limb pain" and "psychotherapy", published in the last 10 years, in English and Spanish, finding 49 items. After reviewing the abstracts, 25 articles were excluded for not being related to the objective of the research. Additionally cross references of included articles and literature were reviewed.

OBJECTIVES

To describe the psychotherapies used in the management of phantom limb pain, their effectiveness and clinical application reported in the literature.

AIMS

The mechanisms underlying phantom limb pain were initially explained, as were the published studies on the usefulness of some psychotherapies such as mirror visual feedback and immersive virtual reality, visual imagery, desensitization and reprocessing eye movements and hypnosis.

CONCLUSIONS

The phantom limb pain is a complex syndrome that requires pharmacological and psychotherapeutic intervention. The psychotherapies that have been used the most as adjuvants in the treatment of phantom limb pain are mirror visual feedback, desensitization and reprocessing eye movements, imagery and hypnosis. Studies with more representative samples, specifically randomized trials are required.

Hand-to-Face Remapping But No Differences in Temporal Discrimination Observed on the Intact Hand Following Unilateral Upper Limb Amputation

Unilateral major limb amputation causes changes in sensory perception. Changes may occur within not only the residual limb but also the intact limb as well as the brain. We tested the hypothesis that limb amputation may result in the detection of hand sensation during stimulation of a non-limb-related body region. We further investigated the responses of unilateral upper limb amputees and individuals with all limbs intact to temporally based sensory tactile testing of the fingertips to test the hypothesis that changes in sensory perception also have an effect on the intact limb. Upper extremity amputees were assessed for the presence of referred sensations (RSs)—experiencing feelings in the missing limb when a different body region is stimulated, to determine changes within the brain that occur due to an amputation. Eight of 19 amputees (42.1%) experienced RS in the phantom limb with manual tactile mapping on various regions of the face. There was no correlation between whether someone had phantom sensations or phantom limb pain and where RS was found. Six of the amputees had either phantom sensation or pain in addition to RS induced by facial stimulation. Results from the tactile testing showed that there were no significant differences in the accuracy of participants in the temporal order judgment tasks (p = 0.702), whereby participants selected the digit that was tapped first by a tracking paradigm that resulted in correct answers leading to shorter interstimulus intervals (ISIs) and incorrect answers increasing the ISI. There were also no significant differences in timing perception, i.e., the threshold accuracy of the duration discrimination task (p = 0.727), in which participants tracked which of the two digits received a longer stimulus. We conclude that many, but not all, unilateral upper limb amputees experience phantom hand sensation and/or pain with stimulation of the face, suggesting that there could be postamputation changes in neuronal circuitry in somatosensory cortex. However, major unilateral limb amputation does not lead to changes in temporal order judgment or timing perception tasks administered via the tactile modality of the intact hand in upper limb amputees.

The meaning and consequences of amputation and mastectomy from the perspective of pain and suffering

BACKGROUND

The concepts 'pain' and 'suffering' are frequently treated as synonymous. However, they are clearly distinct phenomena. Phantom phenomena including pain and sensory disturbances are still recognized as long-lasting problems after limb amputation and after mastectomy. The complex nature of phantom phenomena makes the interpretation of its results ambiguous, regarding the prevalence of pain, sensory disturbances and the accompanying suffering. There is clinical experience that suffering is a great burden for the individual but there is a lack of systematic studies of patients' own evaluations of the suffering caused by their phantom phenomena.

OBJECTIVES

The overall aim of this study was to identify and describe patients' suffering related to, and as a part, of their post-amputation situation.

METHODS

The present study constitutes a part of a prospective, two-year follow up project investigating interviews of 28 men and women in different ages and who have undergone a limb amputation or mastectomy. The reason for amputation or mastectomy varied among the patients and included vascular diseases, cancer (sarcoma and breast-cancer) and trauma. Our ambition was to extract as much variations as possible in different, individualized aspects of the actual pain and suffering producing situation. The participants were, here, invited to open-ended, narrative-oriented interviews one month after the surgery. The interviews were transcribed verbatim and analyzed within qualitative methodology: thematic content analysis.

RESULTS

Twenty-two of 28 interviewees experienced phantom pain and phantom sensations. The two surgical processes amputation and mastectomy meant for a majority of the interviewees a critical event with threatening consequences for everyday life such as loss of function and personal integrity. Nine interviewees felt even stigmatized as a result of their lost body part. Numerous inter-related factors following the amputation/mastectomy, which can inflict severe suffering on the amputee, were uncovered. The context in which the interviewees were informed about the decision to amputate proved to be one such critical and important factor.

CONCLUSION

To understand potential suffering in relation to phantom phenomena, it will never be enough merely to have knowledge of the underlying physiological or neurological mechanisms and/or the intensity of phantom pain and phantom sensations. Rather, it is necessary to find out how the loss of the body part and its everyday consequences are experienced by patients.

IMPLICATIONS

It is important to create time for real dialogue with the patients both during pre-operative preparation and post-operative rehabilitation in order to clarify and verbalize elements that constitute the patients individual suffering. Hopefully this strategy can alleviate future chronic pain problems, severe psycho-social distress and suffering. Such an approach ought to have impact also for perceived suffering after other types of surgery or different invasive treatments.

Mirror therapy for phantom limb pain

Phantom limb pain is a painful sensation that is perceived in a body part that no longer exists. To control this pain, many methods have been used such as medication, physical treatment, nerve block, neuromodulation, surgical treatment and mirror therapy. However, until now, there effects have been uncertain. We report the successful reduction of phantom limb pain using mirror therapy when other treatments initially failed to control the pain.

Phantom limb pain: mechanisms and treatment approaches

The vast amount of research over the past decades has significantly added to our knowledge of phantom limb pain. Multiple factors including site of amputation or presence of preamputation pain have been found to have a positive correlation with the development of phantom limb pain. The paradigms of proposed mechanisms have shifted over the past years from the psychogenic theory to peripheral and central neural changes involving cortical reorganization. More recently, the role of mirror neurons in the brain has been proposed in the generation of phantom pain. A wide variety of treatment approaches have been employed, but mechanism-based specific treatment guidelines are yet to evolve. Phantom limb pain is considered a neuropathic pain, and most treatment recommendations are based on recommendations for neuropathic pain syndromes. Mirror therapy, a relatively recently proposed therapy for phantom limb pain, has mixed results in randomized controlled trials. Most successful treatment outcomes include multidisciplinary measures. This paper attempts to review and summarize recent research relative to the proposed mechanisms of and treatments for phantom limb pain.

The contribution of sympathetic mechanisms to postamputation phantom and residual limb pain: a pilot study

Postamputation pain (PAP) affects over 60% of major limb amputees. One of the main challenges in treating PAP is the difficulty involved in identifying pain mechanism(s), which pertains to both residual limb pain (RLP) and phantom limb pain (PLP). In this study, sympathetic blocks were performed on 17 major limb amputees refractory to treatment, including 2 placebo-controlled blocks done for bilateral amputations. One hour postinjection, mean RLP scores at rest declined from 5.2 (SD 2.8) to 2.8 (SD 2.6) (P = .0002), and PLP decreased from 5.3 (SD 3.1) to 2.3 (SD 2.1) (P = .0009). By 1 week, mean pain scores for RLP and PLP were 4.3 (SD 2.9) and 4.2 (SD 3.0), respectively. Overall, 8 of 16 (50%) patients experienced ≥50% reduction in RLP 1-hour postinjection, with the beneficial effects being maintained at 1 and 8 weeks in 4 and 1 patient(s), respectively. For PLP, 8 of 15 (53%) patients obtained ≥50% decrease in pain 1-hour postblock, with these numbers decreasing to 2 patients at both 1 and 8 weeks. In the 2 bilateral amputees who received controlled injections, mean PLP and RLP at rest scores went from 4.0 and 3.3 to 4.0 and 2.5 1-hour postblock, respectively, on the placebo side. On the treatment side, mean PLP and RLP scores decreased from 7.5 and 6.5, respectively, to 0.

PERSPECTIVE

The results of this study suggest that sympathetic mechanisms play a role in PLP and to a lesser extent, RLP, but that blocks confer long-term benefits in only a small percentage of patients.

The menacing phantom: what pulls the trigger?

Phantom phenomena are frequent following amputation, but how this often painful experience is modified or triggered by spontaneous events or sensations often puzzles amputees and clinicians alike. We explored triggers of phantom phenomena in a heterogeneous sample of 264 upper and lower limb adult amputees with phantom sensations. Participants completed a structured questionnaire to determine the prevalence and nature of the triggers of phantom phenomena. The four categories of triggers identified include: (a) a quarter of participants experiencing psychological, emotional or autonomic triggers; (b) half experiencing behavioral triggers, "forgetting" the limb's absence and attempting to use the phantom; (c) one-fifth experiencing weather-induced triggers; and (d) one-third experiencing sensations referred from parts of the body. Upper limb amputees; and were more likely to experience weather-induced phantom phenomena than lower limb amputees; and upper and lower limb amputees were equally likely to experience referred sensations from the genitals, contradicting the homuncular remapping hypothesis. Traumatic amputees were more likely to report emotional triggers. Further, while those with emotional triggers exhibited poorer acceptance of the limitations of amputation, they were more likely to employ adaptive coping mechanisms. Finally, habitual "forgetting" behaviors were most common soon after amputation, whereas other more adaptive schemata (e.g., self-defense) were equally likely to be performed at any time following amputation. Various likely inter-related mechanisms are discussed in relation to phantom triggers. Ultimately, optimizing stump and neuroma management, as well as restoring function of central networks for pain, limb movement, and amputation-related memories, should help manage spontaneously triggered phantom phenomena.

Adult limb and breast amputees’ experience and descriptions of phantom phenomena—A qualitative study

Background

Phantom phenomena – pain or other sensations appearing to come from amputated body parts – are frequent consequences of amputation and can cause considerable suffering. Also, stump pain, located in the residual limb, is in the literature often related to the phantom phenomena. The condition is not specific to amputated limbs and has, to a lesser extent, been reported to be present after radical surgery in other body parts such as breast, rectum and teeth.

Multi-causal theories are used when trying to understand these phenomena, which are recognized as the result of complex interaction among various parts of the central nervous system confirmed in studies using functional brain imaging techniques.

Functional brain imaging has yielded important results, but without certainty being related to phantom pain as a subjective clinical experience.

There is a wide range of treatment methods for the condition but no documented treatment of choice.

Aims

In this study a qualitative, explorative and prospective design was selected, in the aim to understand the patients’ personal experience of phantom phenomena.

The research questions focused at how patients affected by phantom pain and or phantom sensations describe, understand, and live with these phenomena in their daily life.

This study expanded ‘phantom phenomena’ to also encompass phantom breast phenomenon. Since the latter phenomenon is not as well investigated as the phantom limb, there is clinical concern that this is an underestimated problem for women who have had breasts removed.

Methods

The present study forms the first part of a larger, longitudinal study. Only results associated with data from the first interviews with patients, one month after an amputation, are presented here. At this occasion, 28 patients who had undergone limb amputation (20) or mastectomy (8) were interviewed. The focused, semi-structured interviews were recorded, transcribed, and then analyzed using discourse-narrative analysis.

Results

The interviewees had no conceptual problems in talking about the phenomena or distinguishing between various types of discomfort and discomfort episodes. Their experience originated from a vivid, functioning body that had lost one of its parts. Further, the interviewees reported the importance of rehabilitation and advances in prosthetic technology. Loss of mobility struck older amputees as loss of social functioning, which distressed them more than it did younger amputees. Phantom sensations, kinetic and kinesthetic perceptions, constituted a greater problem than phantom pain experienced from the amputated body parts. The descriptions by patients who had had mastectomies differed from those by patients who had lost limbs in that the phantom breast could be difficult to describe and position spatially.

The clinical implication of this study is that when phantom phenomena are described as everyday experience, they become a psychosocial reality that supplements the definition of phantom phenomena in scientific literature and clinical documentation.

Conclusions

There is a need for clinical dialogues with patients, which besides, providing necessary information about the phenomena to the patients creates possibilities for health professionals to carefully listen to the patients’ own descriptions of which functional losses or life changes patients fear the most. There is a need for more qualitative studies in order to capture the extreme complexity of the pain–control system will be highlighted.

Central mechanisms in phantom limb perception: The past, present and future

Phantom limbs provide valuable insight into the mechanisms underlying bodily awareness and ownership. This paper reviews the complexity of phantom limb phenomena (proprioception, form, position, posture and telescoping), and the various contributions of internal constructs of the body, or body schema, and neuromatrix theory in explaining these phenomena. Specific systems and processes that have received little attention in phantom limb research are also reviewed and highlighted as important future directions, These include prosthesis embodiment and extended physiological proprioception (i.e., the extension of the body's "area of influence" that thereby extends one's innate sense of proprioception, mirror neurons and cross-referencing of the phantom limb with the intact limb (and the related phenomena of perceiving referred sensations and mirrored movements in the phantom form the intact limb). The likely involvements of the body schema and the body-self neuromatrix, mirror neurons, and cross-callosal and ipsilateral mechanisms in phantom limb phenomena all suggest that the perception of a "normal" phantom limb (that is, a non-painful phantom that has the sensory qualities of an intact limb) is more than likely an epiphenomenon of normal functioning, action understanding and empathy, and potentially may even be evolutionarily adaptive and perhaps necessary. Phantom pain, however, may be a maladaptive failure of the neuromatrix to maintain global bodily constructs.

Incidence of Phantom Phenomena Including Phantom Limb Pain 6 Months After Major Lower Limb Amputation in Patients With Peripheral Vascular Disease

OBJECTIVES

Contentions exist regarding the true incidence of phantom limb pain (PLP) and other associated post-amputation phenomena. Recognizing and understanding these phenomena would assist in the rehabilitation of amputees. This study was designed to investigate all post-amputation phenomena in a homogenous group of amputees.

METHODS

Prospective amputees were recruited prior to amputation of a lower limb due to peripheral vascular disease. All survivors were followed 6 months after surgery and interviewed to identify post-amputation phenomena, including phantom sensations, PLP, and stump pain.

RESULTS

Sixty amputees were recruited and 52 survived until the 6-month interview. Phantom sensations were universal, and aspects of the non-painful phenomena, including kinetic, kinesthetic, and exteroceptive components, were identified at varying rates within the sample. PLP was found in 78.8% of the survivors, and 51.2% had stump pain. Super-added phenomena occurred in 15.4%. Links were found between PLP and stump pain (P=0.01) and PLP and the ability to move the phantom (P=0.01). No link was found between PLP and telescoping of the phantom (P=0.47).

CONCLUSIONS

Phantom phenomena are associated with many myths. This study starts to unravel myth from fact, but further study is required before this enigmatic condition and its influence on rehabilitation are fully understood.

Topiramate for Phantom Limb Pain: A Time-Series Analysis

There is growing evidence of topiramate's efficacy in treating neuropathic pain. This article reports a detailed analysis of the response of four amputee subjects with phantom limb pain. Individual time-series analyses revealed that three out of four amputee participants receiving topiramate had statistically significant decreases in pain, with the peak effect noted at 800 mg daily. This analysis supports a hypothesis that topiramate may be effective in reducing phantom limb pain, and suggests a definitive study is indicated.

Phantom Breast Pain as a Source of Functional Loss

Although physicians are aware of phantom limb pain, which can occur in up to 85% of patients who undergo amputation, and its potential effect on functional status, the presence of phantom pain after amputation of other body parts such as the breast and its effect on function may be less appreciated. We report the case of a 63-yr-old woman with multiple sclerosis who underwent a modified radical mastectomy for left intraductal breast carcinoma. After her mastectomy, she required a brief course of inpatient rehabilitation and was discharged from rehabilitation independent, with feeding, dressing, hygiene, and transfers. Two months after her mastectomy, she had difficulty with these tasks because of phantom breast pain. Accurate diagnosis of her pain and successful treatment resulted in a return to premorbid functional status.