Evidence Base for Mirror Therapy
There is a growing literature both on the theoretical basis of how mirror therapy works, the neuroscience underpinning this theory and the areas of medicine that mirror therapy is useful in. We have split the current literature into clinical areas.
Review Papers
The best review paper on the subject is the following one by Ramachandran & Altschuler.
If you are a non medic or just want to read one paper on the subject read this one.These guys write very well and are at the very top of their field.
The use of visual feedback, in particular mirror visual feedback, in restoring brain function. - Ramachandran and Altschuler, in Brain volume 132, in July 2009.
Abstract:
“This article reviews the potential use of visual feedback, focusing on mirror visual feedback, introduced over 15 years ago, for the treatment of many chronic neurological disorders that have long been regarded as intractable such as phantom pain, hemiparesis from stroke and complex regional pain syndrome. Apart from its clinical importance, mirror visual feedback paves the way for a paradigm shift in the way we approach neurological disorders. Instead of resulting entirely from irreversible damage to specialized brain modules, some of them may arise from short-term functional shifts that are potentially reversible. If so, relatively simple therapies can be devised--of which mirror visual feedback is an example--to restore function.”
http://www.ncbi.nlm.nih.gov/pubmed/19506071?dopt=Citation
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Mirror therapy in the treatment of Stroke
The neuronal correlates of mirror therapy: an fMRI study on mirror induced visual illusions in patients with stroke. - Michielsen, ME 2010
Abstract:
“Aim To investigate the neuronal basis for the effects of mirror therapy in patients with stroke. Methods 22 patients with stroke participated in this study. The authors used functional MRI to investigate neuronal activation patterns in two experiments. In the unimanual experiment, patients moved their unaffected hand, either while observing it directly (no-mirror condition) or while observing its mirror reflection (mirror condition). In the bimanual experiment, patients moved both hands, either while observing the affected hand directly (no-mirror condition) or while observing the mirror reflection of the unaffected hand in place of the affected hand (mirror condition). A two-factorial analysis with movement (activity vs rest) and mirror (mirror vs no mirror) as main factors was performed to assess neuronal activity resultant of the mirror illusion. Results Data on 18 participants were suitable for analysis. Results showed a significant interaction effect of movement×mirror during the bimanual experiment. Activated regions were the precuneus and the posterior cingulate cortex (p<0.05 false discovery rate). Conclusion In this first study on the neuronal correlates of the mirror illusion in patients with stroke, the authors showed that during bimanual movement, the mirror illusion increases activity in the precuneus and the posterior cingulate cortex, areas associated with awareness of the self and spatial attention. By increasing awareness of the affected limb, the mirror illusion might reduce learnt non-use. The fact that the authors did not observe mirror-related activity in areas of the motor or mirror neuron system questions popular theories that attribute the clinical effects of mirror therapy to these systems.”
http://www.ncbi.nlm.nih.gov/pubmed/20861065?dopt=Citation
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Motor Recovery and Cortical Reorganization After Mirror Therapy in Chronic Stroke Patients: A Phase II Randomized Controlled Trial. - Michielsen, ME 2010
Abstract:
“OBJECTIVE: To evaluate for any clinical effects of home-based mirror therapy and subsequent cortical reorganization in patients with chronic stroke with moderate upper extremity paresis. METHODS: A total of 40 chronic stroke patients (mean time post .onset, 3.9 years) were randomly assigned to the mirror group (n = 20) or the control group (n = 20) and then joined a 6-week training program. Both groups trained once a week under supervision of a physiotherapist at the rehabilitation center and practiced at home 1 hour daily, 5 times a week. The primary outcome measure was the Fugl-Meyer motor assessment (FMA). The grip force, spasticity, pain, dexterity, hand-use in daily life, and quality of life at baseline-posttreatment and at 6 months-were all measured by a blinded assessor. Changes in neural activation patterns were assessed with functional magnetic resonance imaging (fMRI) at baseline and posttreatment in an available subgroup (mirror, 12; control, 9). RESULTS: Posttreatment, the FMA improved more in the mirror than in the control group (3.6 +/- 1.5, P < .05), but this improvement did not persist at follow-up. No changes were found on the other outcome measures (all Ps > .05). fMRI results showed a shift in activation balance within the primary motor cortex toward the affected hemisphere in the mirror group only (weighted laterality index difference 0.40 +/- 0.39, P < .05). CONCLUSION: This phase II trial showed some effectiveness for mirror therapy in chronic stroke patients and is the first to associate mirror therapy with cortical reorganization. Future research has to determine the optimum practice intensity and duration for improvements to persist and generalize to other functional domains.”
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=21051765
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Mirror therapy promotes recovery from severe hemiparesis: a randomized controlled trial. - Dohle, C 2009
Abstract:
“MT early after stroke is a promising method to improve sensory and attentional deficits and to support motor recovery in a distal plegic limb.”
http://www.ncbi.nlm.nih.gov/pubmed/19074686?dopt=Citation
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The use of visual feedback, in particular mirror visual feedback, in restoring brain function. - Ramachandran, VS 2009
Abstract:
“This article reviews the potential use of visual feedback, focusing on mirror visual feedback, introduced over 15 years ago, for the treatment of many chronic neurological disorders that have long been regarded as intractable such as phantom pain, hemiparesis from stroke and complex regional pain syndrome. Apart from its clinical importance, mirror visual feedback paves the way for a paradigm shift in the way we approach neurological disorders. Instead of resulting entirely from irreversible damage to specialized brain modules, some of them may arise from short-term functional shifts that are potentially reversible. If so, relatively simple therapies can be devised--of which mirror visual feedback is an example--to restore function.”
http://www.ncbi.nlm.nih.gov/pubmed/19506071?dopt=Citation
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Systematic review of the effectiveness of mirror therapy in upper extremity function. - Ezendam, D 2009
Abstract:
“ Most of the evidence for mirror therapy is from studies with weak methodological quality. The present review showed a trend that mirror therapy is effective in upper limb treatment of stroke patients and patients with CRPS, whereas the effectiveness in other patient groups has yet to be determined.”
http://www.ncbi.nlm.nih.gov/pubmed/19903124?dopt=Citation
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Mirror therapy improves hand function in subacute stroke: a randomized controlled trial. - Yavuzer, G 2008
Abstract:
“In our group of subacute stroke patients, hand functioning improved more after mirror therapy in addition to a conventional rehabilitation program compared with a control treatment immediately after 4 weeks of treatment and at the 6-month follow-up, whereas mirror therapy did not affect spasticity.”
http://www.ncbi.nlm.nih.gov/pubmed/18295613?dopt=Citation
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Mirror therapy in a patient with a fractured wrist and no active wrist extension. - Altschuler, EL 2008
Abstract:
“We report a patient in whom mirror therapy, training moving both hands while watching the reflection of the present or good hand in a parasaggital mirror - a method used for phantom limb and stroke patients - was extremely useful after a fractured wrist with good passive, but no active, extension.”
http://www.ncbi.nlm.nih.gov/pubmed/18335358?dopt=Citation
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Interactive visuo-motor therapy system for stroke rehabilitation. - Eng, K 2007
Abstract:
“We present a virtual reality (VR)-based motor neurorehabilitation system for stroke patients with upper limb paresis. It is based on two hypotheses: (1) observed actions correlated with self-generated or intended actions engage cortical motor observation, planning and execution areas ("mirror neurons"); (2) activation in damaged parts of motor cortex can be enhanced by viewing mirrored movements of non-paretic limbs. We postulate that our approach, applied during the acute post-stroke phase, facilitates motor re-learning and improves functional recovery. The patient controls a first-person view of virtual arms in tasks varying from simple (hitting objects) to complex (grasping and moving objects). The therapist adjusts weighting factors in the non-paretic limb to move the paretic virtual limb, thereby stimulating the mirror neuron system and optimizing patient motivation through graded task success. We present the system's neuroscientific background, technical details and preliminary results.”
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17687578
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Mirror therapy enhances lower-extremity motor recovery and motor functioning after stroke: a randomized controlled trial. - Sutbeyaz, S 2007
Abstract:
“OBJECTIVE: To evaluate the effects of mirror therapy, using motor imagery training, on lower-extremity motor recovery and motor functioning of patients with subacute stroke. DESIGN: Randomized, controlled, assessor-blinded, 4-week trial, with follow-up at 6 months. SETTING: Rehabilitation education and research hospital. PARTICIPANTS: A total of 40 inpatients with stroke (mean age, 63.5 y), all within 12 months poststroke and without volitional ankle dorsiflexion. INTERVENTIONS: Thirty minutes per day of the mirror therapy program, consisting of nonparetic ankle dorsiflexion movements or sham therapy, in addition to a conventional stroke rehabilitation program, 5 days a week, 2 to 5 hours a day, for 4 weeks. MAIN OUTCOME MEASURES: The Brunnstrom stages of motor recovery, spasticity assessed by the Modified Ashworth Scale (MAS), walking ability (Functional Ambulation Categories [FAC]), and motor functioning (motor items of the FIM instrument). RESULTS: The mean change score and 95% confidence interval (CI) of the Brunnstrom stages (mean, 1.7; 95% CI, 1.2-2.1; vs mean, 0.8; 95% CI, 0.5-1.2; P=.002), as well as the FIM motor score (mean, 21.4; 95% CI, 18.2-24.7; vs mean, 12.5; 95% CI, 9.6-14.8; P=.001) showed significantly more improvement at follow-up in the mirror group compared with the control group. Neither MAS (mean, 0.8; 95% CI, 0.4-1.2; vs mean, 0.3; 95% CI, 0.1-0.7; P=.102) nor FAC (mean, 1.7; 95% CI, 1.2-2.1; vs mean, 1.5; 95% CI, 1.1-1.9; P=.610) showed a significant difference between the groups. CONCLUSIONS: Mirror therapy combined with a conventional stroke rehabilitation program enhances lower-extremity motor recovery and motor functioning in subacute stroke patients.”
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17466722
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Motor imagery and stroke rehabilitation: a critical discussion. - de Vries, S 2007
Abstract:
Motor disorders are a frequent consequence of stroke and much effort is invested in the re-acquisition of motor control. Although patients often regain some of their lost function after therapy, most remain chronically disabled. Functional recovery is achieved largely through reorganization processes in the damaged brain. Neural reorganization depends on the information provided by sensorimotor efferent-afferent feedback loops. It has, however, been shown that the motor system can also be activated "offline" by imagining (motor imagery) or observing movements. The discovery of mirror neurones, which fire not only when an action is executed, but also when one observes another person performing the same action, also show that our action system can be used "online" as well as offline. It is an intriguing question as to whether the information provided by motor imagery or motor observation can lead to functional recovery and plastic changes in patients after stroke. This article reviews the evidence for motor imagery or observation as novel methods in stroke rehabilitation.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17225031
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Training with a mirror in rehabilitation of the hand - Rosen, B 2005
Abstract:
“Treatment with a mirror gives an illusion of function in a missing or non-functioning hand. The method is based on the concept that the central representation of phantoms and body image can change rapidly, and has been described in the treatment of phantom pain and stroke. We show in three pilot cases new applications for the use of the mirror in rehabilitation after hand surgery.”
http://www.hubmed.org/display.cgi?uids=16019738
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Plasticity and functional recovery in neurology - Ramachandran, V S 2005
Abstract:
Experiments on patients with phantom limbs suggest that neural connections in the adult human brain are much more malleable than previously assumed. Three weeks after amputation of an arm, sensations from the ipsilateral face are referred to the phantom; this effect is caused by the sensory input from the face skin 'invading' and activating deafferented hand zones in the cortex and thalamus. Many phantom arms are 'paralysed' in a painful position. If a mirror is propped vertically in the sagittal plane and the patient looks at the reflection of his/her normal hand, this reflection appears superimposed on the 'felt' position of the phantom. Remarkably, if the real arm is moved, the phantom is felt to move as well and this sometimes relieves the painful cramps in the phantom. Mirror visual feedback (MVF) has shown promising results with chronic regional pain syndrome and hemiparesis following stroke. These results suggest two reasons for a paradigm shift in neurorehabilitation. First, there appears to be tremendous latent plasticity even in the adult brain. Second, the brain should be thought of, not as a hierarchy of organised autonomous modules, each of which delivers its output to the next level, but as a set of complex interacting networks that are in a state of dynamic equilibrium with the brain's environment. Both principles can be potentially exploited in a clinical context to facilitate recovery of function.
http://www.hubmed.org/display.cgi?uids=16138492
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Mirror, mirror on the wall: viewing a mirror reflection of unilateral hand movements facilitates ipsilateral M1 excitability - Garry, M I 2005
Abstract:
Primary motor cortex (M1) excitability is modulated by both ipsilateral limb movement and passive observation of movement of the contralateral limb. An interaction of these effects within M1 may account for recent research suggesting improved functional recovery of the impaired arm following stroke by viewing a mirror reflection of movements of the unimpaired arm superimposed over the (unseen) impaired arm. This hypothesis was tested in the present study using single-pulse transcranial magnetic stimulation (TMS) in eight neurologically healthy subjects. Excitability of M1 ipsilateral to a phasic, unilateral hand movement was measured while subjects performed paced (1 Hz), unilateral index finger-thumb opposition movements. Motor evoked potentials (MEPs) were obtained from the inactive first dorsal interosseous (FDI) in each of four viewing conditions: Active (viewing the active hand), Central (viewing a mark positioned between hands), Inactive (viewing the inactive hand) and Mirror (viewing a mirror-reflection of the active hand in a mirror oriented in the mid-sagittal plane) and with both hands at rest (Rest). MEPs were significantly enhanced during ipsilateral hand movement compared with the Rest condition (P<0.05). Largest MEPs were obtained in the Mirror condition, and this was significant compared with both the Inactive and Central viewing conditions (P<0.05). There was no difference between the dominant and non-dominant hand. Excitability of M1 ipsilateral to a unilateral hand movement is facilitated by viewing a mirror reflection of the moving hand. This finding provides neurophysiological evidence supporting the application of mirror therapy in stroke rehabilitation.
http://www.hubmed.org/display.cgi?uids=15754176
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Simulation of bilateral movement training through mirror reflection: a case report demonstrating an occupational therapy technique for hemiparesis - Stevens, J A 2004
Abstract:
In rehabilitation for hemiparesis, one of the goals of an occupational therapist is to practice upper extremity tasks with the recovering individual. The practice is intended to strengthen muscles and refine movements. It also provides examples for the recovering body and brain as they attempt to reestablish the now delicate cognitive and neural connections mediating voluntary behavior. However, the paresis significantly limits the movement sequence possibilities that may be physically practiced. We outline a method for using simulation of movement, which is intended to provide a means for experiencing a range of smooth and controlled movements completed by a paretic limb. The simulation provides a compelling perceptual experience of bilateral motion beyond the current capabilities of the affected limb. The benefits of this technique after a 3-week course of the simulation practice are exemplified by the presented case study that reveals improved function as demonstrated by increases in Fugl-Meyer scores and faster movement speeds as demonstrated by decreased movement times for the Jebsen test of hand function.
http://www.hubmed.org/display.cgi?uids=14872400
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Training with computer-supported motor imagery in post-stroke rehabilitation - Gaggioli, A 2004
Abstract:
Converging lines of evidence suggest that motor imagery (the mental simulation of a motor act within working memory) is associated with subliminal activation of the motor system. This observation has led to the hypothesis that cortical activation during motor imagery may affect the acquisition of specific motor skills and help the recovery of motor function. In this paper, we describe a clinical protocol in which we use interactive tools to stimulate motor imagery in hemiplegic stroke patients, thereby helping them to recover lost motor function. The protocol consists of an inpatient and an outpatient phase, combining physical and mental practice. In the inpatient phase, patients are trained in a laboratory setting, using a custom-made interactive workbench (VR Mirror). After discharge, patients use a portable device to guide mental and physical practice in a home setting. The proposed strategy is based on the hypotheses that: (a) combined physical and mental practice can make a cost-effective contribution to the rehabilitation of stroke patients, (b) effective mental practice is not possible without some form of support, from a therapist (as in our inpatient phase) or from technology (as in the outpatient phase), (c) the inclusion of an outpatient phase will allow the patient to practice more often than would otherwise be possible, therefore increasing the speed and/or effectiveness of learning, and (d) the use of interactive technology will reduce the patient's need for skilled support, therefore improving the cost-effectiveness of training.
http://www.hubmed.org/display.cgi?uids=15257833
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Using motor imagery in the rehabilitation of hemiparesis - Stevens, J A 2003
Abstract:
To examine the effectiveness of using motor imagery training in the rehabilitation of hemiparesis.A before-after trial with clinical and behavioral analyses of single cases.Academic-affiliated rehabilitation hospital.Two survivors of embolic middle cerebral artery stroke that resulted in chronic hemiparesis.A motor imagery training program consisting of imagined wrist movements (extension, pronation-supination) and mental simulations of reaching and object manipulation making use of a mirror box apparatus. Twelve 1-hour experimental sessions were delivered, 3 times a week for 4 consecutive weeks. Main Outcome Measures: Two clinical assessments, grip strength, 4 wrist functionality measurements, and 3 timed performance tests. All outcome measures were recorded before training began, at 3 times during the intervention month, with 2 additional long-term measurements.Performance of the paretic limb improved after the imagery intervention, indicated by increases in assessment scores and functionality and decreases in movement times. The improvements over baseline performance remained stable over a 3-month period.These results demonstrate the potential for using motor imagery as a cognitive strategy for functional recovery from hemiparesis. The intervention targets the cognitive level of action processing while its effects may be realized in overt behavioral performance.
http://www.hubmed.org/display.cgi?uids=12881842
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Doing it with mirrors: a case study of a novel approach to neurorehabilitation - Sathian, K 2000
Abstract:
Arm amputees can experience the perception of movement of a phantom limb while looking at a mirror reflection of the moving, intact arm superimposed on the perceived phantom. Such use of a mirror to provide illusory visual feedback of movement can be useful in rehabilitation of hemiparetic patients. In this case report, we describe the successful application of "mirror therapy" to the post-stroke rehabilitation of a patient with poor functional use of an upper extremity, due mainly to somatosensory deficits. Mirror therapy facilitated employment of a motor copy strategy (bimanual movements) and later progression to "forced use" of the affected arm. The end result was increased functional use of the affected upper limb.
http://www.hubmed.org/display.cgi?uids=11228952
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Rehabilitation of hemiparesis after stroke with a mirror - Altschuler, E L 1999
no abstract
Mirror therapy in the treatment of Complex Regional Pain Syndrome.
Derangement of body representation in complex regional pain syndrome: report of a case treated with mirror and prisms. - Bultitude, JH & Rafal, RD, Exp Brain Res, 204(3),2010 Jul
Abstract:
“Perhaps the most intriguing disorders of body representation are those that are not due to primary disease of brain tissue. Strange and sometimes painful phantom limb sensations can result from loss of afference to the brain; and Complex Regional Pain Syndrome (CRPS)-the subject of the current report-can follow limb trauma without pathology of either the central or peripheral nervous system. This enigmatic and vexing condition follows relatively minor trauma, and can result in enduring misery and a useless limb. It manifests as severe pain, autonomic dysfunction, motor disability and 'neglect-like' symptoms with distorted body representation. For this special issue on body representation we describe the case of a patient suffering from CRPS, including symptoms suggesting a distorted representation of the affected limb. We report contrasting effects of mirror box therapy, as well as a new treatment-prism adaptation therapy-that provided sustained pain relief and reduced disability. The benefits were contingent upon adapting with the affected limb. Other novel observations suggest that: (1) pain may be a consequence, not the cause, of a disturbance of body representation that gives rise to the syndrome; (2) immobilisation, not pain, may precipitate this reorganisation of somatomotor circuits in susceptible individuals; and (3) limitation of voluntary movement is neither due to pain nor to weakness but, rather, to derangement of body representation which renders certain postures from the repertoire of hand movements inaccessible.”
http://www.ncbi.nlm.nih.gov/pubmed/19967390?dopt=Citation
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Systematic review of the effectiveness of mirror therapy in upper extremity function. - Ezendam, D, Bongers, RM, Jannink, MJ, Disabil Rehabil, 31(26), 2009.Abstract:
“Most of the evidence for mirror therapy is from studies with weak methodological quality. The present review showed a trend that mirror therapy is effective in upper limb treatment of stroke patients and patients with CRPS, whereas the effectiveness in other patient groups has yet to be determined.”
http://www.ncbi.nlm.nih.gov/pubmed/19903124?dopt=Citation
Mirror therapy for chronic complex regional pain syndrome type 1 and stroke. - Cacchio, A 2009
No Abstract
http://www.ncbi.nlm.nih.gov/pubmed/19657134?dopt=Citation
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Mirror visual feedback for the treatment of complex regional pain syndrome (type 1). - McCabe, CS, Haigh, RC, Blake, DR, Curr Pain Headache Rep, 12(2), 103-7, 2008 Apr
Abstract:
“Mirror visual feedback was originally devised as a therapeutic tool to relieve perceived involuntarily movements and paralysis in the phantom limb. Since this pioneering work was conducted in the mid-1990s, the technique has been applied to relieve pain and enhance movement in other chronic conditions such as stroke and complex regional pain syndrome (CRPS) type 1. This review describes how mirror visual feedback was first developed with amputees, its original application in CRPS, and how further research has demonstrated its potential benefit within graded motor imagery programs. We discuss the potential mechanisms behind this technique and consider the implications for clinical practice.”
http://www.ncbi.nlm.nih.gov/pubmed/18474189?dopt=Citation
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Phantoms in Rheumatology - McCabe, C S, Haigh, R C, Shenker, N G, Lewis, J, Blake, D R, Novartis Found Symp, 260, 154-174, 2004Abstract:
“This paper examines rheumatology pain and how it may relate to amputee phantom limb pain (PLP), specifically as experienced in rheumatoid arthritis, fibromyalgia and complex regional pain syndrome (CRPS). Clinical findings, which suggest cortical sensory reorganization, are discussed and illustrated for each condition. It is proposed that this sensory reorganization generates pain and altered body image in rheumatology patients in the same manner as has previously been hypothesized for amputees with PLP; that is via a motor/sensory conflict. The correction of this conflict through the provision of appropriate visual sensory input, using a mirror, is tested in a population of patients with CRPS. Its analgesic efficacy is assessed in those with acute, intermediate and chronic disease. Finally, the hypothesis is taken to its natural conclusion whereby motor/sensory conflict is artificially generated in healthy volunteers and chronic pain patients to establish whether sensory disturbances can be created where no pain symptoms exists and exacerbated when it is already present. The findings of our studies support the hypothesis that a mismatch between motor output and sensory input creates sensory disturbances, including pain, in rheumatology patients and healthy volunteers. We propose the term 'ominory' to describe the central monitoring mechanism and the resultant sensory disturbances as a dissensory state.”
http://www.hubmed.org/display.cgi?uids=15283449
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Mirror visual feedback for the treatment of complex regional pain syndrome (type 1). - McCabe, CS 2008
Abstract:
“Mirror visual feedback was originally devised as a therapeutic tool to relieve perceived involuntarily movements and paralysis in the phantom limb. Since this pioneering work was conducted in the mid-1990s, the technique has been applied to relieve pain and enhance movement in other chronic conditions such as stroke and complex regional pain syndrome (CRPS) type 1. This review describes how mirror visual feedback was first developed with amputees, its original application in CRPS, and how further research has demonstrated its potential benefit within graded motor imagery programs. We discuss the potential mechanisms behind this technique and consider the implications for clinical practice.”
http://www.ncbi.nlm.nih.gov/pubmed/18474189?dopt=Citation
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Current management of reflex sympathetic dystrophy syndrome (complex regional pain syndrome type I). - Berthelot, JM 2006
Abstract:
Although no major advances have occurred in the curative treatment of reflex sympathetic dystrophy syndrome (RSDS), new pathogenic insights may soon lead to innovative approaches, which may also prove effective in alleviating some forms of neuropathic pain. Preventing nerve compression and ischemia-reperfusion injury constitute valuable measures for preventing RSDS. Vitamin C administration can also prevent RSDS, together with clonidine in high-risk patients. Short-term glucocorticoid therapy has been found effective in preventing RSDS after stroke but has not been evaluated in other situations. Beneficial effects of bisphosphonates have been documented in several placebo-controlled trials. Placebo-controlled trials of ketamine and spinal cord stimulation are in order to confirm or refute the promising results obtained in open-label studies. Mirror visual feedback was introduced recently for the rehabilitation of patients with RSDS but needs to be evaluated in randomized controlled trials.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=16837228
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Graded motor imagery is effective for long-standing complex regional pain syndrome: a randomised controlled trial - Moseley, G L 2004
Abstract:
Complex regional pain syndrome type 1 (CRPS1) involves cortical abnormalities similar to those observed in phantom pain and after stroke. In those groups, treatment is aimed at activation of cortical networks that subserve the affected limb, for example mirror therapy. However, mirror therapy is not effective for chronic CRPS1, possibly because movement of the limb evokes intolerable pain. It was hypothesised that preceding mirror therapy with activation of cortical networks without limb movement would reduce pain and swelling in patients with chronic CRPS1. Thirteen chronic CRPS1 patients were randomly allocated to a motor imagery program (MIP) or to ongoing management. The MIP consisted of two weeks each of a hand laterality recognition task, imagined hand movements and mirror therapy. After 12 weeks, the control group was crossed-over to MIP. There was a main effect of treatment group (F(1, 11) = 57, P < 0.01) and an effect size of approximately 25 points on the Neuropathic pain scale. The number needed to treat for a 50% reduction in NPS score was approximately 2. The effect of treatment was replicated in the crossed-over control subjects. The results uphold the hypothesis that a MIP initially not involving limb movement is effective for CRPS1 and support the involvement of cortical abnormalities in the development of this disorder. Although the mechanisms of effect of the MIP are not clear, possible explanations are sequential activation of cortical pre-motor and motor networks, or sustained and focussed attention on the affected limb, or both.
http://www.hubmed.org/display.cgi?uids=15109523
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Using motor imagery in the rehabilitation of Phantom Limb Pain
Derangement of body representation in complex regional pain syndrome: report of a case treated with mirror and prisms. - Bultitude, JH & Rafal, RD, Exp Brain Res, 204(3),2010 Jul
Abstract:
“Perhaps the most intriguing disorders of body representation are those that are not due to primary disease of brain tissue. Strange and sometimes painful phantom limb sensations can result from loss of afference to the brain; and Complex Regional Pain Syndrome (CRPS)-the subject of the current report-can follow limb trauma without pathology of either the central or peripheral nervous system. This enigmatic and vexing condition follows relatively minor trauma, and can result in enduring misery and a useless limb. It manifests as severe pain, autonomic dysfunction, motor disability and 'neglect-like' symptoms with distorted body representation. For this special issue on body representation we describe the case of a patient suffering from CRPS, including symptoms suggesting a distorted representation of the affected limb. We report contrasting effects of mirror box therapy, as well as a new treatment-prism adaptation therapy-that provided sustained pain relief and reduced disability. The benefits were contingent upon adapting with the affected limb. Other novel observations suggest that: (1) pain may be a consequence, not the cause, of a disturbance of body representation that gives rise to the syndrome; (2) immobilisation, not pain, may precipitate this reorganisation of somatomotor circuits in susceptible individuals; and (3) limitation of voluntary movement is neither due to pain nor to weakness but, rather, to derangement of body representation which renders certain postures from the repertoire of hand movements inaccessible.”
http://www.ncbi.nlm.nih.gov/pubmed/19967390?dopt=Citation
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Mirrored, imagined and executed movements differentially activate sensorimotor cortex in amputees with and without phantom limb pain - Diers, M 2010
Abstract:
Extended viewing of movements of the intact hand in a mirror as well as motor imagery has been shown to decrease pain in phantom pain patients. We used functional magnetic resonance imaging to assess the neural correlates of mirrored, imagined and executed hand movements in 14 upper extremity amputees - 7 with phantom limb pain (PLP) and 7 without phantom limb pain (non-PLP) and 9 healthy controls (HC). Executed movement activated the contralateral sensorimotor area in all three groups but ipsilateral cortex was only activated in the non-PLP and HC group. Mirrored movements activated the sensorimotor cortex contralateral to the hand seen in the mirror in the non-PLP and the HC but not in the PLP. Imagined movement activated the supplementary motor area in all groups and the contralateral primary sensorimotor cortex in the non-PLP and HC but not in the PLP. Mirror- and movement-related activation in the bilateral sensorimotor cortex in the mirror movement condition and activation in the sensorimotor cortex ipsilateral to the moved hand in the executed movement condition were significantly negatively correlated with the magnitude of phantom limb pain in the amputee group. Further research must identify the causal mechanisms related to mirror treatment, imagined movements or movements of the other hand and associated changes in pain perception.
http://www.hubmed.org/display.cgi?uids=20359825
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Pre-amputation mirror therapy may prevent development of phantom limb pain: a case series. - Hanling, SR 2010
Abstract:
We report the cases of 4 patients who performed daily mirror therapy for 2 wk before undergoing elective limb amputation. One patient experienced no phantom limb pain (PLP). Two patients experienced rare episodes of mild PLP without effect on their participation in physical therapy (PT) or their quality of life. One patient reported daily, brief episodes of moderate PLP without effect on his participation in PT or his stated quality of life. These results indicate that preoperative mirror therapy may improve postamputation PT compliance and decrease the incidence of PLP. Future prospective studies are needed to confirm the results of this case series.
http://www.ncbi.nlm.nih.gov/pubmed/19917622?dopt=Citation
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Mirror Visual Feedback Therapy. A Practical Approach - McCabe, C 2010
Abstract
Mirror visual feedback (MVF) was first proposed as a therapy to relieve amputee phantom limb pain in the early 1990s. It is increasingly used to treat a range of other chronic pain conditions. The evidence base to date is limited. Much of the literature consists of pilot projects or case study designs although larger randomized controlled trails are now emerging. However, the described protocols for MVF are inadequate to adapt to clinical practice. In addition, the therapist sees a heterogeneous population whose characteristics may fall outside those of the tight inclusion/exclusion criteria of research studies. This article provides the theoretical background to MVF and a detailed description of applying this therapy in clinical practice.
http://www.hubmed.org/display.cgi?uids=21106347
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Phantom limb pain: theories and therapies - Weeks, S R 2010
Abstract
Since the beginning of the conflicts in Iraq and Afghanistan, there has been a dramatic increase in the number of military service members with single and multiple-limb amputations. Phantom limb pain (PLP) frequently develops in these individuals. As a result, identifying the best methods to treat PLP is critical. The review highlights areas of inquiry related to phantom pain, with a focus on PLP.This review discusses phantom sensations and phantom pain that arise after amputation of a body part, and summarizes the differences between the 2 conditions. Characteristics of PLP are also discussed, including the onset, duration, and location of PLP. Theories explaining the etiology and presence of PLP are reviewed, along with the numerous treatment options reported in the published data for such pain, including the use of mirrors for treating pain. We conclude with a description of one military hospital's experiences with PLP.Although more research has been done in previous years, this review identifies the need for continuing investigations. The etiology of PLP needs to be determined through more vigorous investigation, and a focus must be placed on defining treatment options in addition to mirror therapy that will improve the quality of life of those who suffer from this condition.
http://www.hubmed.org/display.cgi?uids=20827116
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Training with virtual visual feedback to alleviate phantom limb pain - Mercier, C 2009
Abstract:
Performing phantom movements with visual virtual feedback, or mirror therapy, is a promising treatment avenue to alleviate phantom limb pain. However the effectiveness of this approach appears to vary from one patient to another.To assess the individual response to training with visual virtual feedback and to explore factors influencing the response to that approach.Eight male participants with phantom limb pain (PLP) resulting from either a traumatic upper limb amputation or a brachial plexus avulsion participated in this single case multiple baseline study. Training was performed 2 times per week for 8 weeks where a virtual image of a missing limb performing different movements was presented and the participant was asked to follow the movements with his phantom limb.Patients reported an average 38% decrease in background pain on a visual analog scale (VAS), with 5 patients out of 8 reporting a reduction greater than 30%. This decrease in pain was maintained at 4 weeks postintervention in 4 of the 5 participants. No significant relationship was found between the long-term pain relief and the duration of the deafferentation or with the immediate pain relief during exposure to the feedback.These results support the use of training with virtual feedback to alleviate phantom limb pain. Our observations suggest that between-participant differences in the effectiveness of the treatment might be related more to a difference in the susceptibility to the virtual visual feedback, than to factors related to the lesion, such as the duration of the deafferentation.
http://www.hubmed.org/display.cgi?uids=19171946
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Phantom limb pain--a phenomenon of proprioceptive memory? - Anderson-Barnes, V C 2009
Abstract:
Despite the amount of research that has been conducted on phantom limb pain (PLP), the etiology of the condition remains unknown, and treatment options are limited. After an individual loses a limb, the brain continues to detect the presence of the missing limb even though it is no longer attached to the body, likely through proprioceptive signals. The majority of patients with amputations either report the feeling of volitional control over their phantom or a phantom limb that is frozen in a specific position. Many patients also experience PLP. Here we propose a new theory, termed "proprioceptive memory," which may explain some of the unique experiences amputees encounter. We also suggest that memories of the limb's position prior to amputation remain embedded within an individual's subconscious, and pain memories that may be associated with each limb position contribute not only to PLP, but to the experience of a fixed or frozen limb. We suspect that there are memory networks for pain--and other sensations, either positive or negative--that are associated with each limb position, and propose that these memories evolved to protect our bodies from repeated injury. A discussion of mirror therapy as a treatment option for PLP is also provided, as well as an explanation for the efficacy of mirror therapy. The paper offers a unique insight into how and why amputees experience these unusual phenomena.
http://www.hubmed.org/display.cgi?uids=19556069
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Size reduction using Mirror Visual Feedback (MVF) reduces phantom pain - Ramachandran, V S 2009
Abstract:
Following limb amputation patients continue to feel the vivid presence of a phantom limb. A majority of patients also experience pain in the phantom and sometimes (as in our case DS) the pain is severe. Remarkably we find that optically 'resurrecting' the phantom with a mirror and using a lens to make the phantom appear to shrink caused the pain to 'shrink' as well.
http://www.hubmed.org/display.cgi?uids=19657972
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The use of visual feedback, in particular mirror visual feedback, in restoring brain function. - Ramachandran, VS 2009
Abstract:
“This article reviews the potential use of visual feedback, focusing on mirror visual feedback, introduced over 15 years ago, for the treatment of many chronic neurological disorders that have long been regarded as intractable such as phantom pain, hemiparesis from stroke and complex regional pain syndrome. Apart from its clinical importance, mirror visual feedback paves the way for a paradigm shift in the way we approach neurological disorders. Instead of resulting entirely from irreversible damage to specialized brain modules, some of them may arise from short-term functional shifts that are potentially reversible. If so, relatively simple therapies can be devised--of which mirror visual feedback is an example--to restore function.”
http://www.ncbi.nlm.nih.gov/pubmed/19506071?dopt=Citation
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Exploratory findings with virtual reality for phantom limb pain; from stump motion to agency and analgesia. - Cole, J 2009
Abstract:
This technique, which has shown similar success rates to trials of a virtual mirror box, is relatively cheap and portable, and will allow further trials in a home environment.
http://www.ncbi.nlm.nih.gov/pubmed/19191061?dopt=Citation
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Therapy of phantom limb pain - Schwarzer, A 2009
Abstract:
About 80 % of all extremity amputations suffer from phantom limb pain following the operation. In this context, it is important to differentiate between painful phantom limb sensations, non-painful phantom limb sensations and residual limb pain. The pathophysiology of phantom limb pain is not fully understood. Current research findings ascribe a major pathophysiological role to cortical changes as well as a disturbed body perception. Peripheral and spinal mechanisms appear less relevant in the development of phantom limb pain. An essential part of the therapy is the pharmacological treatment with antidepressants, anticonvulsives and opioids. Another significant aspect of therapy is senso-motory training, important to mention here would be mirror therapy, lateralisation and motor imaging. In case of an elective amputation, an epidural or axiliar plexus catheter should be considered prior to the amputation. The perioperative treatment with ketamine is debated.
http://www.ncbi.nlm.nih.gov/pubmed/19266417?dopt=Citation
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Self-delivered home-based mirror therapy for lower limb phantom pain - Darnall, B D 2009
Abstract:
Home-based patient-delivered mirror therapy is a promising approach in the treatment of phantom limb pain. Previous studies and case reports of mirror therapy have used a therapist-guided, structured protocol of exercises. No case report has described treatment for either upper or lower limb phantom pain by using home-based patient-delivered mirror therapy. The success of this case demonstrates that home-based patient-delivered mirror therapy may be an efficacious, low-cost treatment option that would eliminate many traditional barriers to care.
http://www.hubmed.org/display.cgi?uids=19096290
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Mirror therapy for phantom limb pain--a systematic review - Seidel, S 2009
Abstract:
The aim of this review was to evaluate the evidence for the treatment of phantom limb pain with mirror therapy.Randomised controlled studies were identified by a systematic search strategy in the databases "Medline" and "The Cochrane Library". The studies were evaluated using the quality criteria of the JADAD-scale.Three small-sized randomised controlled studies were identified. Unfortunately, these studies lacked methodological quality. One of them found a significant decrease of phantom pain after four weeks of daily mirror therapy sessions. Two other studies could not find a significant difference in the reduction of phantom limb pain between intervention- and control-groups. To date, there is only circumstantial evidence for mirror therapy in phantom pain. Hence, no firm recommendations regarding this treatment option are possible.More sufficiently powered randomised controlled studies with high methodological quality are mandatory to investigate the analgesic effect of mirror therapy in phantom limb pain.
http://www.hubmed.org/display.cgi?uids=19657605
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Mirror visual feedback alleviates deafferentation pain, depending on qualitative aspects of the pain: a preliminary report - Sumitani, M 2008
Abstract:
Following lesions in somatosensory pathways, deafferentation pain often occurs. Patients report that the pain is qualitatively complex, and its treatment can be difficult. Mirror visual feedback (MVF) treatment can improve deafferentation pain. We sought to classify the qualities of the pain in order to examine whether the potential analgesic effect of MVF depends on these qualities.Twenty-two patients with phantom limb pain, or pain related to spinal cord or nerve injury, performed a single MVF procedure. Before and after the MVF procedure, we evaluated phantom limb awareness, movement representation of the phantom or affected/paralysed limb, pain intensity on an 11-point numerical rating scale (0-10) and the qualities of the pain [skin surface-mediated (superficial pain) vs deep tissue-mediated (deep pain)] using lists of pain descriptors for each of the two categories.Fifteen of the patients perceived the willed visuomotor imagery of the phantom or affected/paralysed limb after the MVF procedure. In most of the patients, a reduction in pain intensity and a decrease in the reporting of deep-pain descriptors were linked to the emergence of willed visuomotor imagery.In this pilot study, we roughly classified the pain descriptor items into two types for evaluating the qualities of deafferentation pain. We found that visually induced motor imagery by MVF was more effective for reducing deep pain than superficial pain. This suggests that the analgesic effect of MVF treatment does depend on the qualities of the pain. Further research will be required to confirm that this effect is a specific consequence of MVF.
http://www.hubmed.org/display.cgi?uids=18463143
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Mirror therapy in a patient with a fractured wrist and no active wrist extension. - Altschuler, EL 2008
Abstract:
We report a patient in whom mirror therapy, training moving both hands while watching the reflection of the present or good hand in a parasaggital mirror - a method used for phantom limb and stroke patients - was extremely useful after a fractured wrist with good passive, but no active, extension.
http://www.ncbi.nlm.nih.gov/pubmed/18335358?dopt=Citation
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Mirror therapy for phantom limb pain - Chan, B L 2007
No abstract available
http://www.hubmed.org/display.cgi?uids=18032777
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Mirror feed-back - a new method for the treatment of neuropathic pain - Schwarzer, A 2007
Abstract:
The mirror feedback therapy is a method for treatment of neuropathic pain syndromes that are associated with a missing or disordered afferent sensory input. That concerns especially the phantom limb pain, the pain after plexus or spinal nerve root injury and the complex regional pain syndrome. This therapeutic method has been increasingly implemented in the past few years. Its theoretical background rest upon recent pain research findings that refer to changes in the cortical organization and the influence of sensory and motor training effects on the pain experience. During the therapy the patients are instructed to use the mirror in a way that the image of the mirrored healthy limb seems to appear in the place of the missing or affected extremity. The mirror image produces an illusion of two "healthy" limbs. An ergotherapeutic training program with sensory and motor training elements based on the visual impressions is performed additionally.
http://www.hubmed.org/display.cgi?uids=17924298
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Graded motor imagery for pathologic pain: a randomized controlled trial - Moseley, G L 2006
Abstract:
Phantom limb and complex regional pain syndrome type 1 (CRPS1) are characterized by changes in cortical processing and organization, perceptual disturbances, and poor response to conventional treatments. Graded motor imagery is effective for a small subset of patients with CRPS1.To investigate whether graded motor imagery would reduce pain and disability for a more general CRPS1 population and for people with phantom limb pain.Fifty-one patients with phantom limb pain or CRPS1 were randomly allocated to motor imagery, consisting of 2 weeks each of limb laterality recognition, imagined movements, and mirror movements, or to physical therapy and ongoing medical care.There was a main statistical effect of treatment group, but not diagnostic group, on pain and function. The mean (95% CI) decrease in pain between pre- and post-treatment (100 mm visual analogue scale) was 23.4 mm (16.2 to 30.4 mm) for the motor imagery group and 10.5 mm (1.9 to 19.2 mm) for the control group. Improvement in function was similar and gains were maintained at 6-month follow-up.Motor imagery reduced pain and disability in these patients with complex regional pain syndrome type I or phantom limb pain, but the mechanism, or mechanisms, of the effect are not clear.
http://www.hubmed.org/display.cgi?uids=17082465
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Plasticity and functional recovery in neurology - Ramachandran, V S 2005
Abstract:
Experiments on patients with phantom limbs suggest that neural connections in the adult human brain are much more malleable than previously assumed. Three weeks after amputation of an arm, sensations from the ipsilateral face are referred to the phantom; this effect is caused by the sensory input from the face skin 'invading' and activating deafferented hand zones in the cortex and thalamus. Many phantom arms are 'paralysed' in a painful position. If a mirror is propped vertically in the sagittal plane and the patient looks at the reflection of his/her normal hand, this reflection appears superimposed on the 'felt' position of the phantom. Remarkably, if the real arm is moved, the phantom is felt to move as well and this sometimes relieves the painful cramps in the phantom. Mirror visual feedback (MVF) has shown promising results with chronic regional pain syndrome and hemiparesis following stroke. These results suggest two reasons for a paradigm shift in neurorehabilitation. First, there appears to be tremendous latent plasticity even in the adult brain. Second, the brain should be thought of, not as a hierarchy of organised autonomous modules, each of which delivers its output to the next level, but as a set of complex interacting networks that are in a state of dynamic equilibrium with the brain's environment. Both principles can be potentially exploited in a clinical context to facilitate recovery of function.
http://www.hubmed.org/display.cgi?uids=16138492
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Training with a mirror in rehabilitation of the hand - Rosen, B 2005
Abstract:
Treatment with a mirror gives an illusion of function in a missing or non-functioning hand. The method is based on the concept that the central representation of phantoms and body image can change rapidly, and has been described in the treatment of phantom pain and stroke. We show in three pilot cases new applications for the use of the mirror in rehabilitation after hand surgery.
http://www.hubmed.org/display.cgi?uids=16019738
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Mirror treatment of lower limb phantom pain: a case study - MacLachlan, M 2004
Abstract:
Phantom limb pain (PLP) can be an enduring and distressing experience for people with amputations. Previous research has shown that 'mirror treatment' can reduce PLP for some people who have an upper limb amputation, and that it can increase a sense of motor control over the phantom in people with lower limb amputations who are not reporting PLP. There has been no previous report of therapeutic 'mirror treatment' for lower-limb phantom pain.We present the first case study of the use of 'mirror treatment' in a person with a lower limb amputation who was reporting PLP at the time of treatment.During the intervention there was a significant reduction in his PLP, an increase in sense of motor control over the phantom and a change in aspects of the phantom limb that was experienced.This case study, conducted in a conventional clinical setting, supports the potential of 'mirror treatment' for PLP in people with a lower limb amputation.
http://www.hubmed.org/display.cgi?uids=15497919
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Phantoms in rheumatology - McCabe, C S 2004
Abstract:
This paper examines rheumatology pain and how it may relate to amputee phantom limb pain (PLP), specifically as experienced in rheumatoid arthritis, fibromyalgia and complex regional pain syndrome (CRPS). Clinical findings, which suggest cortical sensory reorganization, are discussed and illustrated for each condition. It is proposed that this sensory reorganization generates pain and altered body image in rheumatology patients in the same manner as has previously been hypothesized for amputees with PLP; that is via a motor/sensory conflict. The correction of this conflict through the provision of appropriate visual sensory input, using a mirror, is tested in a population of patients with CRPS. Its analgesic efficacy is assessed in those with acute, intermediate and chronic disease. Finally, the hypothesis is taken to its natural conclusion whereby motor/sensory conflict is artificially generated in healthy volunteers and chronic pain patients to establish whether sensory disturbances can be created where no pain symptoms exists and exacerbated when it is already present. The findings of our studies support the hypothesis that a mismatch between motor output and sensory input creates sensory disturbances, including pain, in rheumatology patients and healthy volunteers. We propose the term 'ominory' to describe the central monitoring mechanism and the resultant sensory disturbances as a dissensory state.
http://www.hubmed.org/display.cgi?uids=15283449
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Doing it with mirrors: a case study of a novel approach to neurorehabilitation - Sathian, K 2000
Abstract:
Arm amputees can experience the perception of movement of a phantom limb while looking at a mirror reflection of the moving, intact arm superimposed on the perceived phantom. Such use of a mirror to provide illusory visual feedback of movement can be useful in rehabilitation of hemiparetic patients. In this case report, we describe the successful application of "mirror therapy" to the post-stroke rehabilitation of a patient with poor functional use of an upper extremity, due mainly to somatosensory deficits. Mirror therapy facilitated employment of a motor copy strategy (bimanual movements) and later progression to "forced use" of the affected arm. The end result was increased functional use of the affected upper limb.
http://www.hubmed.org/display.cgi?uids=11228952
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Synaesthesia in phantom limbs induced with mirrors. - Ramachandran, VS 1996
Abstract:
Although there is a vast clinical literature on phantom limbs, there have been no experimental studies on the effects of visual input on phantom sensations. We introduce an inexpensive new device--a 'virtual reality box'--to resurrect the phantom visually to study inter-sensory effects. A mirror is placed vertically on the table so that the mirror reflection of the patient's intact had is 'superimposed' on the felt position of the phantom. We used this procedure on ten patients and found the following results. 1. In six patients, when the normal hand was moved, so that the phantom was perceived to move in the mirror, it was also felt to move; i.e. kinesthetic sensations emerged in the phantom. In D.S. this effect occurred even though he had never experienced any movements in the phantom for ten years before we tested him. He found the return of sensations very enjoyable. 2. Repeated practice led to a permanent 'disappearance' of the phantom arm in patient D.S. and the hand became telescoped into the stump near the shoulder. 3. Using an optical trick, impossible postures--e.g. extreme hyperextension of the fingers--could be induced visually in the phantom. In one case this was felt as a transient 'painful tug' in the phantom. 4. Five patients experienced involuntary painful 'clenching spasms' in the phantom hand and in four of them the spasms were relieved when the mirror was used to facilitate 'opening' of the phantom hand; opening was not possible without the mirror. 5. In three patients, touching the normal hand evoked precisely localized touch sensations in the phantom. Interestingly, the referral was especially pronounced when the patients actually 'saw' their phantom being touched in the mirror. Indeed, in a fourth patient (R.L.) the referral occurred only if he saw his phantom being touched: a curious form of synaesthesia. These experiments lend themselves readily to imaging studies using PET and fMRI. Taken collectively, they suggest that there is a considerable amount of latent plasticity even in the adult human brain. For example, precisely organized new pathways, bridging the two cerebral hemispheres, can emerge in less than three weeks. Furthermore, there must be a great deal of back and forth interaction between vision and touch, so that the strictly modular, hierarchical model of the brain that is currently in vogue needs to be replaced with a more dynamic, interactive model, in which 're-entrant' signalling plays the main role.
http://www.ncbi.nlm.nih.gov/pubmed/8637922?dopt=Citation
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