A Clinical Evaluation of Postamputation Phenomena Including Phantom Limb Pain after Lower Limb Amputation in Dysvascular Patients

Phantom Limb Pain and Painful Neuroma After Dysvascular Lower-Extremity Amputation: A Systematic Review and Meta-Analysis

BACKGROUND

Phantom limb pain (PLP) and symptomatic neuroma can be debilitating and significantly impact the quality of life of amputees. However, the prevalence of PLP and symptomatic neuromas in patients following dysvascular lower limb amputation (LLA) has not been reliably established. This systematic review and meta-analysis evaluates the prevalence and incidence of phantom limb pain and symptomatic neuroma after dysvascular LLA.

METHODS

Four databases (Embase, MEDLINE, Cochrane Central, and Web of Science) were searched on October 5th, 2022. Prospective or retrospective observational cohort studies or cross-sectional studies reporting either the prevalence or incidence of phantom limb pain and/or symptomatic neuroma following dysvascular LLA were identified. Two reviewers independently conducted the screening, data extraction, and the risk of bias assessment according to the PRISMA guidelines. To estimate the prevalence of phantom limb pain, a meta-analysis using a random effects model was performed.

RESULTS

Twelve articles were included in the quantitative analysis, including 1924 amputees. A meta-analysis demonstrated that 69% of patients after dysvascular LLA experience phantom limb pain (95% CI 53-86%). The reported pain intensity on a scale from 0-10 in LLA patients ranged between 2.3 ± 1.4 and 5.5 ± .7. A single study reported an incidence of symptomatic neuroma following dysvascular LLA of 5%.

CONCLUSIONS

This meta-analysis demonstrates the high prevalence of phantom limb pain after dysvascular LLA. Given the often prolonged and disabling nature of neuropathic pain and the difficulties managing it, more consideration needs to be given to strategies to prevent it at the time of amputation.

Risk Factors Analysis of Phantom Limb Pain in Amputees with Malignant Tumors

Purpose

Postamputation neuropathic pain is a common disease in patients with malignant tumor amputation, seriously affecting amputees' quality of life and mental health. The objective of this study was to identify independent risk factors for phantom limb pain in patients with tumor amputation and to construct a risk prediction model.

Methods

Patients who underwent amputation due to malignant tumors from 2013 to 2023 were retrospectively analyzed and divided into phantom limb pain group and non-phantom limb pain group. To determine which preoperative factors would affect the occurrence of phantom limb pain, we searched for candidate factors by univariate analysis and used multivariate logistic regression analysis to identify independent factors and construct a predictive model. The receiver operating characteristic curve (ROC) was drawn to further evaluate the accuracy of the prediction model in evaluating the phantom limb pain after amputation of bone and soft tissue tumors.

Results

Multivariate analysis showed that age (OR, 1.054; 95% CI, 1.027 to 1.080), preoperative pain (OR, 5.773; 95% CI, 2.362 to 14.104), number of surgeries (OR, 3.425; 95% CI, 1.505 to 7.795), amputation site (OR, 5.848; 95% CI, 1.837 to 18.620), amputation level (OR, 8.031; 95% CI, 2.491 to 25.888) were independent risk factors for phantom limb pain for bone and soft tissue tumors. The the area under the curve (AUC) of this model was 0.834.

Conclusion

Risk factors for postoperative phantom limb pain were the site of amputation, proximal amputation, preoperative pain, multiple amputations, and older age. These factors will help surgeons to individualize and stratify phantom limb pain and help patients with risk counseling. In particular, an informed clinical decision targeting those modifiable factors can be considered when needed.

Evolving techniques for reducing phantom limb pain

At least two million people in the United States of America live with lost limbs, and the number is expected to double by 2050, although the incidence of amputations is significantly greater in other parts of the world. Within days to weeks of the amputation, up to 90% of these individuals develop neuropathic pain, presenting as phantom limb pain (PLP). The pain level increases significantly within one year and remains chronic and severe for about 10%. Amputation-induced changes are considered to underlie the causation of PLP. Techniques applied to the central nervous system (CNS) and peripheral nervous system (PNS) are designed to reverse amputation-induced changes, thereby reducing/eliminating PLP. The primary treatment for PLP is the administration of pharmacological agents, some of which are considered but provide no more than short-term pain relief. Alternative techniques are also discussed, which provide only short-term pain relief. Changes induced by various cells and the factors they release are required to change neurons and their environment to reduce/eliminate PLP. It is concluded that novel techniques that utilize autologous platelet-rich plasma (PRP) may provide long-term PLP reduction/elimination.

Relationship between phantom limb pain, function, and psychosocial health in individuals with lower-limb loss

INTRODUCTION

The adverse influence of chronic pain on function and psychological health in the general population is well understood. However, the relationship between phantom limb pain (PLP) after limb loss with function and psychological health is less clear. The study purpose was to assess the influences of PLP presence and intensity on function and psychosocial health in individuals with lower-limb loss (LLL).

METHODS

One hundred two individuals with major LLL completed a study-specific questionnaire on the presence and intensity of their PLP. The Patient-Reported Outcomes Measurement Information System -29 questionnaire was also administered.

RESULTS

Of 102 participants, 64% reported PLP, with a mean intensity of 4.8 ± 2.3 out of 10. Individuals with vs. without PLP demonstrated significantly greater sleep disturbances ( p = 0.03), whereas the differences in function, fatigue, pain interference, depressive symptoms, anxiety, or ability to participate in social roles and activities were not statistically different between groups ( p > 0.05). Of note, mean scores for many of the Patient-Reported Outcomes Measurement Information System-29 short forms among the current sample were similar to the mean of the general population, minimizing the potential clinical impact of PLP on these domains.

CONCLUSIONS

Our findings indicate a lack of meaningful associations between PLP presence or intensity with function, and psychosocial health among individuals with LLL. These findings conflict with previous research suggesting an adverse relationship between PLP, function, and psychosocial health after limb loss.

Perioperative Management of Painful Phantom Limb Syndrome: A Narrative Review and Clinical Management Proposal

Objective: Painful Phantom Limb Syndrome (PPLS) occurs in 50 to 80% of patients undergoing amputation, having a great impact on quality of life, productivity and psychosocial sphere. The objective of this review is to summarize the pharmacological and non-pharmacological strategies, surgical optimization, and provide a multidisciplinary approach aimed at reducing the incidence of chronic pain associated with PPLS in patients undergoing limb amputation.Methods: A narrative review was carried out using Medline, Pubmed, Proquest, LILACS and Cochrane, searching for articles between 2000 and 2021. Articles describing the epidemiology, pathophysiological considerations, and current treatments were selected after a screening process.Results: A multidisciplinary and multimodal approach is required in PPLS, and should include the use of regional techniques, and adjuvants such as NSAIDs, ketamine, lidocaine and gabapentinoids. In addition, an evaluation and continuous management of risk factors for chronic pain in conjunction with the surgical team is necessary.Conclusion: The current literature does not support that a single technique is effective in the prevention of PPLS. However, adequate acute pain control, rehabilitation and early restoration of the body scheme under a multidisciplinary and multimodal approach have shown benefit in the acute setting.

Protocol for a randomized controlled trial to assess the effect of Self-Management for Amputee Rehabilitation using Technology (SMART): An online self-management program for individuals with lower limb loss

BACKGROUND

Lower limb loss (LLL) is a distressing experience with psychological, physical, and social challenges. Education is needed to enhance the coping skills and confidence of patients to improve LLL outcomes. However, access to rehabilitation services and education is limited outside of urban centers. To address this service gap, we co-created an eHealth platform, called Self-Management for Amputee Rehabilitation using Technology (SMART).

OBJECTIVES

First, we will test the effect of SMART and usual care compared with usual care only on walking capacity and confidence among individuals with LLL. Second, we will describe key implementation factors for program delivery and adoption at the person- and provider-level.

METHODS

This is a Type 1 Effectiveness-Implementation Hybrid Design, mixed-methods, multi-site (British Columbia and Ontario, Canada), parallel, assessor-blinded randomized controlled trial. Participants will include adults with unilateral LLL, during early prosthetic fitting (<2 years after casting for initial prosthesis). Participants in both groups will receive usual care. The experimental group will receive SMART with weekly support sessions from a trained peer mentor for goal setting and action planning for six weeks. Participants will be encouraged to continue using SMART for an additional four weeks. The control group will receive usual care, and weekly social contacts for six weeks. The primary outcome measure is walking capacity operationalized as the performance based Timed Up and Go test. The secondary outcome is walking confidence using the Ambulatory Self-Confidence Questionnaire. Outcome measures will be assessed at baseline, immediately post-intervention, and four weeks follow-up. We will describe key implementation factors (such as, participant experience, intervention adoption, fidelity) throughout the study using questionnaires, semi-structured interviews, and direct observation.

RESULTS

No participants have been enrolled.

CONCLUSIONS

SMART has the potential to provide knowledge and skill development to augment rehabilitation outcomes for adults with LLL.

TRIAL REGISTRATION

NCT04953364 in Clinical Trial Registry (https://clinicaltrials.gov/).

Factors Related to Neuropathic Pain following Lower Extremity Amputation

BACKGROUND

Lower extremity amputations are common, and postoperative neuropathic pain (phantom limb pain or symptomatic neuroma) is frequently reported. The use of active treatment of the nerve end has been shown to reduce pain but requires additional resources and should therefore be performed primarily in high-risk patients. The aim of this study was to identify the factors associated with the development of neuropathic pain following above-the-knee amputation, knee disarticulation, or below-the-knee amputation.

METHODS

Retrospectively, 1565 patients with an average follow-up of 4.3 years who underwent a primary above-the-knee amputation, knee disarticulation, or below-the-knee amputation were identified. Amputation levels for above-the-knee amputations and knee disarticulations were combined as proximal amputation level, with below-the-knee amputations being performed in 61 percent of patients. The primary outcome was neuropathic pain (i.e., phantom limb pain or symptomatic neuroma) based on medical chart review. Multivariable logistic regression was performed to identify independent factors associated with neuropathic pain.

RESULTS

Postoperative neuropathic pain was present in 584 patients (37 percent), with phantom limb pain occurring in 34 percent of patients and symptomatic neuromas occurring in 3.8 percent of patients. Proximal amputation level, normal creatinine levels, and a history of psychiatric disease were associated with neuropathic pain. Diabetes, hypothyroidism, and older age were associated with lower odds of developing neuropathic pain.

CONCLUSIONS

Neuropathic pain following lower extremity amputation is common. Factors influencing nerve regeneration, either increasing (proximal amputations and younger age) or decreasing (diabetes, hypothyroidism, and chronic kidney disease) it, play a role in the development of postamputation neuropathic pain.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Central nervous system stimulation therapies in phantom limb pain: a systematic review of clinical trials

Phantom limb pain is a chronic pain syndrome that is difficult to cope with. Despite neurostimulation treatment is indicated for refractory neuropathic pain, there is scant evidence from randomized controlled trials to recommend it as the treatment choice. Thus, a systematic review was performed to analyze the efficacy of central nervous system stimulation therapies as a strategy for pain management in patients with phantom limb pain. A literature search for studies conducted between 1970 and September 2020 was carried out using the MEDLINE and Embase databases. Principles of The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline were followed. There were a total of 10 full-text articles retrieved and included in this review. Deep brain stimulation, repetitive transcranial magnetic stimulation, transcranial direct current stimulation, and motor cortex stimulation were the treatment strategies used in the selected clinical trials. Repetitive transcranial magnetic stimulation and transcranial direct current stimulation were effective therapies to reduce pain perception, as well as to relieve anxiety and depression symptoms in phantom limb pain patients. Conversely, invasive approaches were considered the last treatment option as evidence in deep brain stimulation and motor cortex stimulation suggests that the value of phantom limb pain treatment remains controversial. However, the findings on use of these treatment strategies in other forms of neuropathic pain suggest that these invasive approaches could be a potential option for phantom limb pain patients.

Chronic pain in lower limb amputees: Is there a correlation with the use of perioperative epidural or perineural analgesia?

BACKGROUND

Chronic pain is common in patients who undergo lower limb amputation. The use of epidural or perineural catheters seems to reduce acute pain after surgery but their effects in a longer follow up are unknown.

OBJECTIVE

To evaluate the long-term prevalence of phantom limb sensation (PLS), phantom limb pain (PLP), and residual limb pain (RLP) and their correlation with perioperative use of epidural or perineural catheters.

METHODS

Postal survey. Patients with trans-femoral, trans-tibial or hemi-pelvectomy amputation were asked to partake in the study. The Prosthetic Evaluation Questionnaire was used for the presence of chronic post-surgical pain. Use of catheters was retrieved from medical notes.

RESULTS

57 patients at a mean of 4.4 years follow up were included. PLS was reported in 68.4%, PLP in 63.2 % and RLP in 54.4% of amputees. No correlation was identified between pain syndromes and the presence of individual catheters and the duration of their permanence. The simultaneous use of 2 catheters was related to a lesser presence of PLP.

CONCLUSIONS

Data on prevalence of PLP, PLS and RLP are consistent with the literature. Favourable effects in PLP reduction in the long term follow up was related to the simultaneous use of two catheters.

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.

Phantom Limb Pain and Sensations in Chinese Malignant Tumor Amputees: A Retrospective Epidemiological Study

OBJECTIVE

Phantom limb pain (PLP) was a common problem in malignant tumor amputees that can cause considerable suffering. The purposes of this study were to determine the incidence and factors associated with the occurrence of post-operation PLP, stump limb pain (SLP), and phantom limb sensations (PLS) in tumor amputees within the first month after surgery. Additionally, differences in phantom phenomena between upper and lower extremities were investigated.

METHODS

In total, 162 amputees participated in this retrospective study who underwent malignant limb amputation between 2012 and 2019. Clinical characteristics were collected from medical records and reconfirmed by telephone interviews. A numerical rating scale (NRS) was used to quantitate phantom phenomena. We used analysis of variance and non-parametric statistics for categorical variables and ordinal variables separately.

RESULTS

In the first month after malignant amputation, the incidence of PLP was 54.3%, that of PLS was 65.4%, and that of SLP was 32.7%. The duration of preoperative pain and amputation level was significantly different for the incidence of acute PLP. Further subgroup analysis of amputation level showed that patients whose amputation level was below the wrist and ankle joints had a significantly reduced incidence of PLP (p<0.0083 in Bonferroni test). Binary logistics regression analysis determined that amputation level was the primary risk factor for the incidence of PLP. Factors related to the severity of postoperative PLP also included amputation level, preoperative pain, and amputation times. By comparing the differences between upper and lower limbs after amputation, we found that the incidence of PLS was higher after lower limb amputation, but there was no significant difference in the incidence of PLP and SLP. Preoperative experience of chemotherapy was not a risk factor for PLP.

CONCLUSION

Proximal amputation and long-term preoperative pain seemed to count more for PLP incidence. Further research may be required to individually determine factors associated with the occurrence and chronicity of phantom phenomena.

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.

Prevalence and incidence of phantom limb pain, phantom limb sensations and telescoping in amputees: A systematic rapid review

BACKGROUND AND OBJECTIVE

This systematic, rapid review aimed to critically appraise and synthesize the recent literature (2014-2019) evaluating the incidence and prevalence of post-amputation phantom limb pain (PLP) and sensation (PLS).

DATABASES AND DATA TREATMENT

Five databases (Medline, Embase, Emcare, PsychInfo, Web of Science) and Google Scholar were searched, with two independent reviewers completing eligibility screening, risk of bias assessment and data extraction.

RESULTS

The search identified 1,350 studies with 12 cross-sectional and 3 prospective studies included. Studies evaluated traumatic (n = 5), atraumatic (n = 4), and combined traumatic/atraumatic (n = 6) amputee populations, ranging from 1 month to 33 years post-amputation. Study heterogeneity prevented data pooling. The majority of studies had a high risk of bias, primarily due to limited generalizability. Three studies evaluated PLP incidence, ranging from 2.2% (atraumatic; 1 month) to 41% (combined; 3 months) and 82% (combined; 12 months). Only one study evaluated PLS/telescoping incidence. Across contrasting populations, PLP point prevalence was between 6.7%-88.1%, 1 to 3-month period prevalence was between 49%-93.5%, and lifetime prevalence was high at 76%-87%. Point prevalence of PLS was 32.4%-90%, period prevalence was 65% (1 month) and 56.9% (3 months), and lifetime prevalence was 87%. Telescoping was less prevalent, highest among traumatic amputees (24.6%) within a 1-month prevalence period. Variations in population type (e.g. amputation characteristics) and incidence and prevalence measures likely influence the large variability seen here.

CONCLUSIONS

This review found that lifetime prevalence was the highest, with most individuals experiencing some type of phantom phenomena at some point post-amputation.

SIGNIFICANCE

This systematic rapid review provides a reference for clinicians to make informed prognosis estimates of phantom phenomena for patients undergoing amputation. Results show that most amputees will experience phantom limb pain (PLP) and phantom limb sensations (PLS): high PLP incidence 1-year post-amputation (82%); high lifetime prevalence for PLP (76%-87%) and PLS (87%). Approximately 25% of amputees will experience telescoping. Consideration of individual patient characteristics (cause, amputation site, pre-amputation pain) is pertinent given their likely contribution to incidence/prevalence of phantom phenomena.

Pain issues in the victims with lower-limb amputation: 10 years after the 2008 Sichuan earthquake

PURPOSE

To study the prevalence, intensity, and bothersomeness of amputation-related pain and further to identify the potential risk factors in the victims with lower-limb amputation 10 years after the 2008 Sichuan earthquake.

METHODS

In the cross-sectional study, 66 victims with lower-limb amputation were recruited. The Prostheses Evaluation Questionnaire was used to document the prevalence, intensity, and bothersomeness of amputation-related pain. The bivariate relationships between amputation-related pain and each of demographic characteristics were analyzed.

RESULTS

Majority of the enrolled lower-limb amputees (90.9%) reported to have one or more types of amputation-related pain. The intensity and bothersomeness of amputation-related pain were considered as severe in nearly 40% of these post-earthquake victims. The potential demographic risk factors associated with the prevalence, intensity, and bothersomeness of amputation-related pain were identified, including the age, lower level of education, marital status, employment, and comorbidity.

CONCLUSIONS

The pain coming from phantom limb, residual limb, non-amputated limb, and back was found persistent in the lower-limb amputees 10 years after the 2008 Sichuan earthquake. The findings of this study could provide useful reference for optimization of post-disaster rehabilitation strategies to alleviate chronic pain in the victims following lower-limb amputation.Implications for RehabilitationThe pain coming from phantom limb, residual limb, non-amputated limb, and back was found persistent in the victims with lower-limb amputation 10 years after the 2008 Sichuan earthquake.Continuous post-earthquake assessment and management of amputation-related pain should be taken into consideration for the victims with lower-limb amputation.The comorbidity should be effectively and efficiently controlled for the victims with lower-limb amputation due to its association with the intensity and bothersomeness of amputation-related pain.

More than half of persons with lower limb amputation suffer from chronic back pain or residual limb pain: a systematic review with meta-analysis

Purpose: The aim of this study is to systematically review and critically assess the methodological quality of literature regarding prevalence, characteristics and factors influencing pain, other than phantom limb pain (PLP) in persons with lower limb amputation (LLA).Materials and methods: A systematic review was performed (PROSPERO CRD42019138018). Literature was searched using PubMed, EMBASE, PsycINFO, and PEDro. Studies were included if describing pain other than PLP at least three months after amputation. For residual limb pain (RLP) and back pain, a meta-regression was performed.Results: Fifty-one studies were included in which predominantly young males with a unilateral traumatic amputation using a prosthesis were investigated. Pooled prevalence of RLP was 0.51 (95% CI 0.40-0.62) with a positive association with presence of back pain (p = 0.044) in the univariate meta-regression. Pooled prevalence of back pain was 0.55 (95% CI 0.45-0.64), with a positive association of time since amputation (p < 0.001) and co-occurrence of RLP (p = 0.050).Conclusions: Back pain and RLP are common after LLA. The prevalence of back pain was positively associated with the presence of RLP, and vice versa. Future studies should give more attention to other chronic pain types, to persons with a diabetic or vascular cause of amputation, and to pain-related interference.Implications for RehabilitationBoth back pain and residual limb pain occur in more than 50% of persons with lower limb amputation (LLA), and both pain types are positively associated.Clinicians should be aware that chronic pain is common after LLA and can have a significant impact on the functioning of persons with LLA.Future research on this topic should give more attention to other chronic pain types, to persons with a diabetic or vascular cause of amputation, and to pain-related interference.

An investigation into the effects of a virtual reality system on phantom limb pain: a pilot study

Background

There is no first-line treatment available for phantom limb pain (PLP). For some years, there has been interest in the use of mirrors and other techniques based on visual feedback. Unfortunately, up until now, all published studies have had methodological weaknesses with two recent systematic reviews concluding that therapies of this kind need more evidence to support their use.

Aim

To evaluate the effects of a virtual reality (VR) activity on PLP.

Methods

This was a prospective pilot study of upper limb amputees using questionnaires to evaluate a VR system. Eleven participants were recruited, with nine completing all three sessions of VR. Participants undertook three sessions of VR, one a month for 3 months. Outcome measures were PLP pain intensity using an 11-point numerical rating scale (NRS), number of PLP episodes and duration of the PLP episodes. All participants were also asked for their judgement of change. Open-ended questions captured the qualitative experience of all aspects of the VR experience.

Results

The mean PLP pain score following three VR sessions reduced (6.11 v 3.56) but this was not a statistical difference (t = 2.1, df = 8, p = 0.07). No statistical difference was found for the number of PLP episodes (Pearson chi-square = 3.43, df = 2, p = 0.18) or the duration of each PLP episode (Pearson chi-square = 22.50, df = 16, p = 0.13). Three groups emerged: those whose pain reduced (the majority), those whose pain remained the same (small number) and one those whose pain increased slightly.

Discussion

There is insufficient evidence from these results to identify an effect of VR on PLP; however, this is a small group and qualitatively most were content with the treatment and wanted a longer trial.

Effects of Tactile Desensitization on Postoperative Pain After Amputation Surgery

PURPOSE

Pain in the acute setting after amputation is complex with multiple types of pain experienced, including somatic and neuropathic. No studies have measured multiple pain control modalities while using self-management techniques for acute amputation pain. Desensitization could provide a means of pain control for somatic and neuropathic pain. The purpose of this study was to test the efficacious use and effects of tactile desensitization in managing acute postoperative pain after lower limb amputation.

DESIGN

This was a pre-experimental repeated measure study.

METHODS

Pain description, intensity, anxiety, depression, and medication usage were measured during repeated time periods. Pain intensity was measured before and after each intervention along with efficacy.

FINDINGS

Of the times the intervention was self-administered (n = 50) there was a statistically significant reduction in the pain level (P < .001) with large effect sizes for all paired comparisons. Participants found the intervention efficacious and feasible to use.

CONCLUSIONS

The findings support a reduction in pain intensity scores using pain medication coupled with tactile desensitization.

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.

Traditional and augmented reality mirror therapy for patients with chronic phantom limb pain (PACT study): results of a three-group, multicentre single-blind randomized controlled trial

Objective:

To compare the effects of traditional mirror therapy (MT), a patient-centred teletreatment (PACT) and sensomotor exercises without a mirror on phantom limb pain (PLP).

Design:

Three-arm multicentre randomized controlled trial.

Setting:

Rehabilitation centres, hospital and private practices.

Subjects:

Adult patients with unilateral lower limb amputation and average PLP intensity of at least 3 on the 0–10 Numeric Rating Scale (NRS).

Interventions:

Subjects randomly received either four weeks of traditional MT followed by a teletreatment using augmented reality MT, traditional MT followed by self-delivered MT or sensomotor exercises of the intact limb without a mirror followed by self-delivered exercises.

Main measures:

Intensity, frequency and duration of PLP and patient-reported outcomes assessing limitations in daily life at baseline, 4 weeks, 10 weeks and 6 months.

Results:

In total, 75 patients received traditional MT ( n = 25), teletreatment ( n = 26) or sensomotor exercises ( n = 24). Mean (SD) age was 61.1 (14.2) years and mean (SD) pain intensity was 5.7 (2.1) on the NRS. Effects of MT at four weeks on PLP were not significant. MT significantly reduced the duration of PLP at six months compared to the teletreatment ( P = 0.050) and control group ( P = 0.019). Subgroup analyses suggested significant effects on PLP in women, patients with telescoping and patients with a motor component in PLP. The teletreatment had no additional effects compared to self-delivered MT at 10 weeks and 6 months.

Conclusion:

Traditional MT over four weeks was not more effective than sensomotor exercises without a mirror in reducing PLP, although significant effects were suggested in some subgroups.

Phantom phenomena in limb amputees – a review article

Amputation leading to the loss of a body part is associated not only with significant economic costs, but also serious consequences of medical and socio-psychological nature. It is the ultimate means to save a life or improve its quality. The most difficult challenges faced by amputees include accepting changes regarding their own physiognomy and the resulting life restrictions. The patient subjected to amputation is faced with an extremely difficult adaptation process, during which s/he should strive for a maximum degree of independence. Unfortunately, a large group of patients also struggles with various types of sensations and pain located within the lost limb − i.e., so-called phantom phenomena. This is a special group of phenomena of diverse nature, “located” within the lost limb. The occurrence of phantom limb syndrome in amputee patients is extremely common. This problem affects from 45% to even 98% of patients after amputation of one or both upper and lower limbs. The main purpose of this article is to describe phantom phenomena observed in patients after limb amputation in light of current literature. The definition, historical outline, types of phantom phenomena are presented, as well as hypothetical pathomechanisms, factors influencing the frequency and intensity of phantom phenomena and available treatment methods. The work was based on numerous text sources and the author’s own experience.

Strategies for prevention of lower limb post-amputation pain: A clinical narrative review

Postamputation limb pain or phantom limb pain (PLP) develops due to the complex interplay of peripheral and central sensitization. The pain mechanisms are different during the initial phase following amputation as compared with the chronic PLP. The literature describes extensively about the management of established PLP, which may not be applicable as a preventive strategy for PLP. The novelty of the current narrative review is that it focuses on the preventive strategies of PLP. The institution of preoperative epidural catheter prior to amputation and its continuation in the immediate postoperative period reduced perioperative opioid consumption (Level II). Optimized preoperative epidural or intravenous patient-controlled analgesia starting 48 hours and continuing for 48 hours postoperatively decreased PLP at 6 months (Level II). Preventive role of epidural LA with ketamine (Level II) reduced persistent pain at 1 year and LA with calcitonin decreased PLP at 12 months (Level II). Peripheral nerve catheters have opioid sparing effect in the immediate postoperative period in postamputation patients (Level I), but evidence is low for the prevention of PLP (Level III). Gabapentin did not reduce the incidence or intensity of postamputation pain (Level II). The review in related context mentions evidence regarding therapeutic role of gabapentanoids, peripheral nerve catheters, and psychological therapy in established PLP. In future, randomized controlled trials with long-term follow-up of patients receiving epidural analgesia, perioperative peripheral nerve catheters, oral gabapentanoids, IV ketamine, or mechanism-based modality for prevention of PLP as primary outcome are required.

Perioperative Pain Management Strategies for Amputation: A Topical Review

Objective

To review acute pain management strategies in patients undergoing amputation with consideration of preoperative patient factors, pharmacologic/interventional modalities, and multidisciplinary care models to alleviate suffering in the immediate post-amputation setting.

Background

Regardless of surgical indication, patients undergoing amputation suffer from significant residual limb pain and phantom limb pain in the acute postoperative phase. Most studies have primarily focused on strategies to prevent persistent pain with inclusion of immediate postoperative outcomes as secondary measures. Pharmacologic agents, including gabapentin, ketamine, and calcitonin, and interventional modalities such as neuraxial and perineural catheters, have been examined in the perioperative period.

Design

Focused Literature Review.

Results

Pharmacologic agents (gabapentin, ketamine, calcitonin) have not shown consistent efficacy. Neuraxial analgesia has demonstrated both an opioid sparing and analgesic benefit while results have been mixed regarding perineural catheters in the immediate post-amputation setting. However, several early studies of perineural catheters employed sub-optimal techniques (distal surgical placement), and prolonged use of perineural catheters may provide a sustained benefit. Regardless of analgesic technique, a multidisciplinary approach is necessary for optimal care.

Conclusion

Patient-tailored analgesic regimens utilizing catheter-based techniques are essential in the acute post-amputation phase and should be implemented in all patients undergoing amputation. Future research should focus on improved measurement of acute pain and comparisons of effective analgesic regimens instead of single techniques.

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.

Association between phantom limb complex and the level of amputation in lower limb amputee

Objective

The aim of this study was to evaluate the natural course of phantom limb complex without any treatment after lower limb amputation.

Methods

The study design was consisted of a combination of retrospective review and cross-sectional interview. 101 patients with lower limb amputation were included into the study. Patients were divided into three groups according to the amputation level: i) from hip disarticulation to knee disarticulation (including knee disarticulation) (25 patients, mean age: 55.9, 19 males, 6 females) ii) transtibial amputation (below knee to ankle including ankle disarticulation) (41 patients, mean age: 58.6, 33 males, 8 females) iii) below ankle to toe amputation (35 patients, mean age: 58.7, 26 males, 9 females). The patients were evaluated on both early postoperative period (EPP) and sixth months after the surgery (ASM). The data related amputation including amputation date, level, cause, stump pain (SP), phantom limb pain (PLP), components of PLP, phantom sensation (PS) were recorded based on the information obtained from patients' and hospital files.

Results

Statistically significant differences were found for pain intensity (VAS) between groups for SP and PLP at EPP (p < 0.001, p = 0.036; respectively). The mean VAS score in Group I for SP and PLP was higher than other groups. This differences for SP and PLP did not continue at ASM assessment (p = 0.242, p = 0.580; respectively).

Conclusion

VAS scores for SP in above knee amputations and VAS scores for PLP in above knee amputations and below ankle amputations were higher at EPP. But these high scores had disappeared over time. Management strategies have to be considered particularly in the early postoperative period in patients who had undergone above knee amputation.

Level of Evidence

Level III Prognostic study.

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.