-
Neurologia Medico-chirurgica Mar 2024Phantom limb pain is attributed to abnormal sensorimotor cortical representations. Various feedback treatments have been applied to induce the reorganization of the... (Review)
Review
Phantom limb pain is attributed to abnormal sensorimotor cortical representations. Various feedback treatments have been applied to induce the reorganization of the sensorimotor cortical representations to reduce pain. We developed a training protocol using a brain-computer interface (BCI) to induce plastic changes in the sensorimotor cortical representation of phantom hand movements and demonstrated that BCI training effectively reduces phantom limb pain. By comparing the induced cortical representation and pain, the mechanisms worsening the pain have been attributed to the residual phantom hand representation. Based on our data obtained using neurofeedback training without explicit phantom hand movements and hand-like visual feedback, we suggest a direct relationship between cortical representation and pain. In this review, we summarize the results of our BCI training protocol and discuss the relationship between cortical representation and phantom limb pain. We propose a treatment for phantom limb pain based on real-time neuroimaging to induce appropriate cortical reorganization by monitoring cortical activities.
Topics: Humans; Phantom Limb; Motor Cortex; Sensorimotor Cortex; Hand; Neuroimaging
PubMed: 38267056
DOI: 10.2176/jns-nmc.2023-0206 -
Clinical Rehabilitation Mar 2024Three-phase graded motor imagery (limb laterality, explicit motor imagery, and mirror therapy) has been successful in chronic pain populations. However, when applied to...
OBJECTIVE
Three-phase graded motor imagery (limb laterality, explicit motor imagery, and mirror therapy) has been successful in chronic pain populations. However, when applied to phantom limb pain, an amputation-related pain, investigations often use mirror therapy alone. We aimed to explore evidence for graded motor imagery and its phases to treat phantom limb pain.
DATA SOURCES
A scoping review was conducted following the JBI Manual of Synthesis and Preferred Reporting Items for Systematic Review and Meta-Analyses extension for Scoping Reviews. Thirteen databases, registers, and websites were searched.
REVIEW METHODS
Published works on any date prior to the search (August 2023) were included that involved one or more graded motor imagery phases for participants ages 18+ with amputation and phantom limb pain. Extracted data included study characteristics, participant demographics, treatment characteristics, and outcomes.
RESULTS
Sixty-one works were included representing 19 countries. Most were uncontrolled studies (31%). Many participants were male (75%) and had unilateral amputations (90%) of varying levels, causes, and duration. Most works examined one treatment phase (92%), most often mirror therapy (84%). Few works (3%) reported three-phase intervention. Dosing was inconsistent across studies. The most measured outcome was pain intensity (95%).
CONCLUSION
Despite the success of three-phase graded motor imagery in other pain populations, phantom limb pain research focuses on mirror therapy, largely ignoring other phases. Participant demographics varied, making comparisons difficult. Future work should evaluate graded motor imagery effects and indicators of patient success. The represented countries indicate that graded motor imagery phases are implemented internationally, so future work could have a widespread impact.
Topics: Female; Humans; Male; Amputation, Surgical; Amputees; Imagery, Psychotherapy; Pain Management; Phantom Limb
PubMed: 37849299
DOI: 10.1177/02692155231204185 -
British Journal of Anaesthesia Jul 2001
Review
Topics: Humans; Pain, Postoperative; Phantom Limb; Risk Factors
PubMed: 11460799
DOI: 10.1093/bja/87.1.107 -
Danish Medical Journal Oct 2012Amputation is followed by both painful and non-painful phantom phenomena in a large number of amputees. Non-painful phantom sensations rarely pose any clinical problem,... (Review)
Review
Amputation is followed by both painful and non-painful phantom phenomena in a large number of amputees. Non-painful phantom sensations rarely pose any clinical problem, but 60-80% of all amputees also experience painful sensations (i.e. phantom pain) located to the missing limb. The severity of phantom pain usually decreases with time, but severe pain persists in 5-10% of patients. Pain in the residual limb (i.e. stump pain) is another consequence of amputation. Both stump and phantom pain can be very difficult to treat. Treatment guidelines used for other neuropathic pain conditions are probably the best approximation, especially for the treatment of stump pain. The aim of the present doctoral thesis was to explore some of the mechanisms underlying pain after amputation. Ten studies were carried out (I-X). My PhD thesis from 1998 dealt with pain before the amputation and showed that preamputation pain increases the risk of phantom pain after amputation (I). A perioperative epidural blockade, however, did not reduce the incidence of pain or abnormal sensory phenomena after amputation (II, III). The importance of sensitization before amputation for the subsequent development of pain is supported by study IV, in which pressure pain thresholds obtained at the limb before amputation were inversely related to stump and phantom pain after 1 week. Afferent input from the periphery is likely to contribute to postamputation pain as sodium channels were upregulated in human neuromas (VI), although neuroma removal did not always alleviate phantom pain (V). Sensitization of neurons in the spinal cord also seems to be involved in pain after amputation as phantom pain was reduced by ketamine, an NMDA-receptor antagonist. Another NMDA-receptor antagonist, memantine, and gabapentin, a drug working by binding to the δ2α-subunit of voltage-gated calcium channels, had no effect on phantom pain (VII-IX). Supraspinal factors are also important for pain after amputation as catastrophizing was associated with phantom pain (X). In conclusion, the present doctoral thesis confirmed and expanded the findings by others that several mechanisms are involved in the development and maintenance of phantom pain. A better understanding of the underlying mechanisms will hopefully lead to improved treatment of pain after amputation in the future.
Topics: Amputation Stumps; Humans; Lower Extremity; Pain Measurement; Phantom Limb; Severity of Illness Index; Upper Extremity
PubMed: 23158899
DOI: No ID Found -
Medical Acupuncture Aug 2017Phantom limb pain (PLP) is a common and poorly understood pathology of difficult medical control that progressively takes place after amputation occurs. This article... (Review)
Review
Phantom limb pain (PLP) is a common and poorly understood pathology of difficult medical control that progressively takes place after amputation occurs. This article discusses the multifactorial bases of PLP. These bases involve local changes at the stump level, spinal modifications of excitability, deafferentation, and central sensitization, leading to the development of maladaptive plasticity, and consequentially, defective processing of sensory information by associative neural networks. These changes can be traced by neurophysiology and imaging topographical studies, indicating a degree of cortical reorganization that perpetuates pain and discomfort. Noninvasive brain stimulation can be an alternative way to manage PLP. This article discusses two techniques-transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS)-that have shown promising results for controlling PLP. The modulation that both techniques rely on is based on synaptic mechanisms linked to long-term potentiation and long-term depression phenomena. By applying tDCS or rTMS, clinicians can target processes associated with central sensitization and maladaptive plasticity, while promoting adequate sensory information processing by integrative cognitive behavioral techniques in a comprehensive rehabilitation program. Understanding PLP from a dynamic neurocomputational perspective will help to develop better treatments. Furthermore, Bayesian analysis of sensory information can help guide and monitor therapeutic interventions directed toward PLP resolution.
PubMed: 28874923
DOI: 10.1089/acu.2017.1240 -
Frontiers in Rehabilitation Sciences 2022Currently, there is neither a standardized mode for the documentation of phantom sensations and phantom limb pain, nor for their visualization as perceived by patients....
Currently, there is neither a standardized mode for the documentation of phantom sensations and phantom limb pain, nor for their visualization as perceived by patients. We have therefore created a tool that allows for both, as well as for the quantification of the patient's visible and invisible body image. A first version provides the principal functions: (1) Adapting a 3D avatar for self-identification of the patient; (2) modeling the shape of the phantom limb; (3) adjusting the position of the phantom limb; (4) drawing pain and cramps directly onto the avatar; and (5) quantifying their respective intensities. Our tool (C.A.L.A.) was evaluated with 33 occupational therapists, physiotherapists, and other medical staff. Participants were presented with two cases in which the appearance and the position of the phantom had to be modeled and pain and cramps had to be drawn. The usability of the software was evaluated using the System Usability Scale and its functional range was evaluated using a self-developed questionnaire and semi-structured interview. In addition, our tool was evaluated on 22 patients with limb amputations. For each patient, body image as well as phantom sensation and pain were modeled to evaluate the software's functional scope. The accuracy of the created body image was evaluated using a self-developed questionnaire and semi-structured interview. Additionally, pain sensation was assessed using the SF-McGill Pain Questionnaire. The System Usability Scale reached a level of 81%, indicating high usability. Observing the participants, though, identified several operational difficulties. While the provided functions were considered useful by most participants, the semi-structured interviews revealed the need for an improved pain documentation component. In conclusion, our tool allows for an accurate visualization of phantom limbs and phantom limb sensations. It can be used as both a descriptive and quantitative documentation tool for analyzing and monitoring phantom limbs. Thus, it can help to bridge the gap between the therapist's conception and the patient's perception. Based on the collected requirements, an improved version with extended functionality will be developed.
PubMed: 36189032
DOI: 10.3389/fresc.2022.806114 -
Pain Physician Jul 2004Since the first medical description of post-amputation phenomena reported by Ambrose Paré, persistent phantom pain syndromes have been well recognized. However, they...
Since the first medical description of post-amputation phenomena reported by Ambrose Paré, persistent phantom pain syndromes have been well recognized. However, they continue to be difficult to manage. The three most commonly utilized terms include phantom sensation, phantom pain, and stump pain. Phantom limb sensation is an almost universal occurrence at some time during the first month following surgery. However, most phantom sensations generally resolve after two to three years without treatment, except in the cases where phantom pain develops. The incidence of phantom limb pain has been reported to vary from 0% to 88%. The incidence of phantom limb pain increases with more proximal amputations. Even though phantom pain may diminish with time and eventually fade away, it has been shown that even two years after amputation, the incidence is almost the same as at onset. Consequently, almost 60% of patients continue to have phantom limb pain after one year. In addition, phantom limb pain may also be associated with multiple pain problems in other areas of the body. The third symptom, stump pain, is located in the stump itself. The etiology and pathophysiological mechanisms of phantom pain are not clearly defined. However, both peripheral and central neural mechanisms have been described, along with superimposed psychological mechanisms. Literature describing the management of phantom limb pain or stump pain is in its infancy. While numerous treatments have been described, there is little clinical evidence supporting drug therapy, psychological therapy, interventional techniques or surgery. This review will describe epidemiology, etiology and pathophysiological mechanisms, risk factors, and treatment modalities. The review also examines the effectiveness of various described modalities for prevention, as well as management of established phantom pain syndromes.
PubMed: 16858476
DOI: No ID Found -
Journal of Neural Engineering Sep 2022Electrical stimulation can induce sensation in the phantom limb of individuals with amputation. It is difficult to generalize existing findings as there are many... (Review)
Review
Electrical stimulation can induce sensation in the phantom limb of individuals with amputation. It is difficult to generalize existing findings as there are many approaches to delivering stimulation and to assessing the characteristics and benefits of sensation. Therefore, the goal of this systematic review was to explore the stimulation parameters that effectively elicited referred sensation, the qualities of elicited sensation, and how the utility of referred sensation was assessed.We searched PubMed, Web of Science, and Engineering Village through January of 2022 to identify relevant papers. We included papers which electrically induced referred sensation in individuals with limb loss and excluded papers that did not contain stimulation parameters or outcome measures pertaining to stimulation. We extracted information on participant demographics, stimulation approaches, and participant outcomes.After applying exclusion criteria, 49 papers were included covering nine stimulation methods. Amplitude was the most commonly adjusted parameter (= 25), followed by frequency (= 22), and pulse width (= 15). Of the 63 reports of sensation quality, most reported feelings of pressure (= 52), paresthesia (= 48), or vibration (= 40) while less than half (= 29) reported a sense of position or movement. Most papers evaluated the functional benefits of sensation (= 33) using force matching or object identification tasks, while fewer papers quantified subjective measures (= 16) such as pain or embodiment. Only 15 studies (36%) observed percept intensity, quality, or location over multiple sessions.Most studies that measured functional performance demonstrated some benefit to providing participants with sensory feedback. However, few studies could experimentally manipulate sensation location or quality. Direct comparisons between studies were limited by variability in methodologies and outcome measures. As such, we offer recommendations to aid in more standardized reporting for future research.
Topics: Amputees; Artificial Limbs; Feedback, Sensory; Humans; Phantom Limb; Sensation
PubMed: 36001115
DOI: 10.1088/1741-2552/ac8c38 -
Minerva Anestesiologica Apr 2021Phantom Limb Pain (PLP) is a dysesthesic painful sensations perceived in the lost limb, resulting from complex interactions between structural and functional nervous...
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.
Topics: Amputation, Surgical; Amputees; Humans; Mental Recall; Phantom Limb
PubMed: 33432796
DOI: 10.23736/S0375-9393.20.15067-3 -
Scientific Reports Oct 2018There is an increasing need to extend the control possibilities of upper limb amputees over their prosthetics, especially given the development of devices with numerous...
There is an increasing need to extend the control possibilities of upper limb amputees over their prosthetics, especially given the development of devices with numerous active joints. One way of feeding pattern recognition myoelectric control is to rely on the myoelectric activities of the residual limb associated with phantom limb movements (PLM). This study aimed to describe the types, characteristics, potential influencing factors and trainability of upper limb PLM. Seventy-six below- and above-elbow amputees with major amputation underwent a semi-directed interview about their phantom limb. Amputation level, elapsed time since amputation, chronic pain and use of prostheses of upper limb PLM were extracted from the interviews. Thirteen different PLM were found involving the hand, wrist and elbow. Seventy-six percent of the patients were able to produce at least one type of PLM; most of them could execute several. Amputation level, elapsed time since amputation, chronic pain and use of myoelectric prostheses were not found to influence PLM. Five above-elbow amputees participated in a PLM training program and consequently increased both endurance and speed of their PLM. These results clearly encourage further research on PLM-associated muscle activation patterns for future PLM-based modes of prostheses control.
Topics: Adult; Artificial Limbs; Female; Humans; Male; Middle Aged; Phantom Limb; Upper Extremity
PubMed: 30337602
DOI: 10.1038/s41598-018-33643-0