Developing an in-depth understanding of the prevalence, risk factors and treatment recommendations for phantom limb pain, and patient-generated care priorities for people who have undergone lower limb amputations

Introduction: Phantom limb pain is a common complication in people who have undergone limb amputation, with prevalence estimates ranging between 29% and 85.6%. Current systematic-review evidence suggests that recommended treatments are no more effective than placebo for reducing Phantom Limb Pain (PLP). Moreover, there is evidence suggesting that people with amputations may not be getting the treatment they want at different time-points after amputation. In consideration of these points, a research project comprised of a series of interconnected studies aimed to develop an in-depth understanding of the global burden of PLP and patient care priorities after limb amputations, and generate expert recommendations on the best management of PLP in people with amputations. Methods: The research project is comprised of a series of four interconnected studies addressing the four primary aims of the project. A systematic review and meta-analysis were conducted to determine the pooled prevalence estimate and risk factors for PLP in people with amputations. A cross sectional study was conducted to determine the prevalence and risk factors for PLP in people who had undergone lower limb amputations at Groote Schuur Hospital. An expert Delphi study was conducted to reach expert consensus and make recommendations on the effective treatments for PLP in people with limb amputations. Lastly, a patient Delphi study was conducted to generate patient consensus on care priorities for people who have had lower limb amputation for a year or less and for those who have had lower limb amputations for more than a year. Results: The systematic review and meta-analysis of 39 studies revealed a pooled PLP prevalence estimate of 64% [95%CI: 60.01 – 68.05], with a significantly higher prevalence estimate in studies conducted in developed countries 66.55% [95% CI: 62.02 –71.64] than those conducted in developing countries 53.98% [95% CI: 44.79–63.05] (U = 57, p = 0.03). Risk factors that were consistently positively associated with PLP included having an amputation of a lower limb, stump pain, non-painful phantom sensations, persistent pre-amputation pain, proximal site of amputation, and diabetic cause of amputation. The cross-sectional study using a sample of African people with amputations showed a PLP prevalence of 50.78% [95% CI: 41.80 – 59.72] during the week preceding data collection. In this group of patients, persistent pre-operative pain was the only risk factor associated with PLP in the multivariate logistic regression analysis [OR 2.25 (1.03 – 5.05); P=0.04]. In the expert Delphi study, consensus was reached on one pharmacological (amitriptyline) and six nonpharmacological (Graded Motor Imagery, mirror therapy, Cognitive Behavioural Therapy, virtual reality training, sensory discrimination training, use of a functional prosthesis) treatments that were considered effective for managing PLP, and on two treatments [citalopram (60%) and Pulsed Radiofrequency Stimulation of the dorsal root ganglion (70%)] that were considered ineffective. In the patient Delphi study, consensus was reached on 24 short-term care priorities and 12 long-term care priorities. The general consensus among the participants was that pre-amputation, they wanted education support to help them manage their expectations and prepare for life after amputation. In the early stage after amputation, they wanted help with dealing with the psychological trauma of having lost a limb. In the long-term, however, the participants prioritised the need for living a functional and normal life, with respect and dignity like everyone else. Conclusion: The prevalence of PLP in people with limb amputations is high, and awareness of this condition needs to be raised among healthcare professionals to implement evidence-based strategies for alleviating PLP by targeting the relevant underlying mechanisms and modifiable risk factors. Evidence-based medicine indicates that PLP is best managed using non-pharmacological and noninterventional treatments addressing biopsychosocial contributors for PLP. Finally, preparing people for life after amputation and helping them deal with the psychological trauma of having lost a limb may contribute to improved clinical outcomes that may enable them to live a functional and normal life, with respect and dignity

The effectiveness of graded motor imagery for reducing phantom limb pain and disability in amputees

Introduction Phantom limb pain (PLP) is described as painful sensations felt in the missing portion of an amputated limb. PLP occurs in up to 85% of amputees, making it the most common painful condition secondary to amputation. PLP interferes with sleep, mobility, and work, general activities of daily living and enjoyment of life. Current pharmacological and non-pharmacological interventions have shown limited efficacy for reducing PLP, perhaps because they do not effectively target the mechanisms that have been proposed to underlie PLP in people who have undergone amputations. Graded motor imagery (GMI) is a cortical mechanisms-based intervention which aims to reduce PLP using a graded sequence of strategies including left/right judgements, imagined movements and mirror therapy. The aim of this thesis was to investigate whether the GMI programme is effective for reducing PLP and disability in people who have undergone amputations. Methods A single blinded randomised controlled trial was conducted at Somerset, Khayelitsha and Victoria hospitals in Cape Town, South Africa. The experimental group underwent a 6-week GMI programme where each phase was carried out for two weeks, during which the patient received treatment for 30 minutes on two separate days of the first week (at least one day apart) and continued with a structured home-exercise programme during the first week until the end of the second week. The control group continued with routine care. Data on the outcomes- PLP severity, pain interference with function and health-related quality of life were collected at baseline, 6 weeks and 3 months by a blinded outcome assessor. Results The study recruited 21 participants from which 11 and 10 were randomly allocated to the experimental and control groups respectively. Within group analysis showed that participants in both the experimental and control groups had improved pain severity scores immediately after treatment and at 3-month follow-up. The between-group analysis showed that the experimental group had significantly greater improvements in pain immediately after treatment (p=0.02). However, there was no difference between groups at 3-months follow-up (p=0.14). To explore clinically meaningful improvements in pain, the Number Needed to Treat (NNT) were calculated using a cut-off of 3 points on a 0-10 scale. The NNT were 2 [95% CI: 1.1 – 6.5] and 3 [95% CI: 1.9 – 7.1] immediately after treatment and at 3-months follow-up respectively. For pain interference with function, within group analysis showed that participants in the experimental group had significant improvements immediately after treatment and at 3-month follow-up. The between-group analysis showed that the experimental group had significantly greater improvements in pain interference with function immediately after treatment (p=0.007) and at 3- month follow-up (p=0.02). The NNT were 1.4 [95% CI: 1 – 1.8] and 1.9 [95% CI: 1.1 – 6.5] immediately after treatment and at 3-months follow-up respectively. For disability, the experimental group had significantly fewer problems with mobility than the control group at 3 months (χ2 = 9.8; p= 0.04). Conclusion The results of the current study provide support for the use of GMI to treat PLP based on the proposition that PLP is driven by cortical mechanisms and that GMI effectively targets these mechanisms. On the basis of the significant pain reduction within the GMI group, the lack of serious adverse effects, and the ease of application, GMI may be a viable treatment for treating PLP in people who have undergone amputations. While more studies using rigorous methodology, including sham treatment, larger sample sizes and a more generalisable sample, are required, the efficacy of GMI coupled with its affordability and low risk, suggest that it is applicable in a resource-constrained primary health setting in South Africa

The prevalence and risk factors for phantom limb pain in people with amputations: A systematic review and meta-analysis

Background: Phantom limb pain (PLP)-pain felt in the amputated limb-is often accompanied by significant suffering. Estimates of the burden of PLP have provided conflicting data. To obtain a robust estimate of the burden of PLP, we gathered and critically appraised the literature on the prevalence and risk factors associated with PLP in people with limb amputations. Methods: Articles published between 1980 and July 2019 were identified through a systematic search of the following electronic databases: MEDLINE/PubMed, PsycINFO, PsycArticles, Cumulative Index to Nursing and Allied Health Literature, Africa-Wide Information, Health Source: Nursing/Academic Edition, SCOPUS, Web of Science and Academic Search Premier. Grey literature was searched on databases for preprints. Two reviewers independently conducted the screening of articles, data extraction and risk of bias assessment. The meta-analyses were conducted using the random effects model. A statistically significant level for the analyses was set at p<0.05. Results: The pooling of all studies demonstrated a prevalence estimate of 64% [95% CI: 60.01-68.05] with high heterogeneity [I2 = 95.95% (95% CI: 95.10-96.60)]. The prevalence of PLP was significantly lower in developing countries compared to developed countries [53.98% vs 66.55%; p = 0.03]. Persistent pre-operative pain, proximal site of amputation, stump pain, lower limb amputation and phantom sensations were identified as risk factors for PLP. Conclusion: This systematic review and meta-analysis estimates that six of every 10 people with an amputation report PLP-a high and important prevalence of PLP. Healthcare professionals ought to be aware of the high rates of PLP and implement strategies to reduce PLP by addressing known risk factors, specifically those identified by the current study

The prevalence of phantom limb pain and associated risk factors in people with amputations: a systematic review protocol

Background The prevalence of phantom limb pain (PLP) in people with amputations is unclear because of the conflicting reports across the literature. It is proposed that the conflicting reports on the prevalence of PLP are a consequence of variations in the time period during which the studies were undertaken, countries in which the studies were conducted and recruitment processes implemented during collection of epidemiological data. In consideration of these factors, we aim to gather and critically appraise relevant literature to determine the prevalence estimate of and risk factors for PLP in people with amputations. Methods We will use a customised search strategy containing relevant words and terms to search the following databases: MEDLINE/PubMed (via EBSCOhost), PsycINFO (via EBSCOhost), PsycArticles, Cumulative Index to Nursing and Allied Health Literature (CINAHL) (via EBSCOhost), Africa-Wide Information (via EBSCOhost), Health Source: Nursing/Academic Edition (via EBSCOhost) SCOPUS, Web of Science and Academic Search Premier (via EBSCOhost). The risk of bias assessment will be conducted using a risk of bias assessment tool for prevalence studies, and data will be extracted using a piloted customised data extraction sheet. Data extracted from individual studies will be entered into Review Manager 5 and assessed for clinical and statistical heterogeneity. Studies will be pooled for meta-analysis using the random-effects model to determine a summary estimate of the prevalence of PLP across included studies. A statistically significant level will be set at p < 0.05. Discussion As far as we know, a systematic review and meta-analysis on the prevalence of, and risk factors for PLP in people with amputations has not been conducted. Given the varying reports in the literature, it is necessary to determine an estimate of the prevalence of PLP to generate an informed conclusion on this subject. The results of this review will be published in an internationally accredited journal and used to inform researchers, clinicians, policy-makers and the public about the burden of, and risk factors for PLP. This will be done with a further aim to improve the quality of pain management in society. Systematic review registration PROSPERO CRD4201809482

Making sense of phantom limb pain

Phantom limb pain (PLP) impacts the majority of individuals who undergo limb amputation. The PLP experience is highly heterogenous in its quality, intensity, frequency and severity. This heterogeneity, combined with the low prevalence of amputation in the general population, has made it difficult to accumulate reliable data on PLP. Consequently, we lack consensus on PLP mechanisms, as well as effective treatment options. However, the wealth of new PLP research, over the past decade, provides a unique opportunity to re-evaluate some of the core assumptions underlying what we know about PLP and the rationale behind PLP treatments. The goal of this review is to help generate consensus in the field on how best to research PLP, from phenomenology to treatment. We highlight conceptual and methodological challenges in studying PLP, which have hindered progress on the topic and spawned disagreement in the field, and offer potential solutions to overcome these challenges. Our hope is that a constructive evaluation of the foundational knowledge underlying PLP research practices will enable more informed decisions when testing the efficacy of existing interventions and will guide the development of the next generation of PLP treatments

Wedelia (Sphagneticola trilobata) - daisy invader of the Pacific Islands: the worst weed in the Pacific?

Can a pretty daisy be compared with the likes of the Anopheles mosquito, the dreaded malaria vector; the brown tree snake that has brought birds and lizards in Guam to extinction; or fire ants that threaten endemic lizards and cause blindness in dogs in New Caledonia? I think so. “Wedelia”, creeping oxeye, or the trailing daisy, formerly known as Wedelia trilobata, but now as Sphagneticola trilobata, a deceptively beautiful, bright emerald-green creeper with bright yellow daisy-like flowers, is one of the world’s most aggressive weeds and listed among the worlds 1000 worst invasive alien species. Native to tropical America from Mexico to Brazil and throughout the Caribbean, wedelia is now cultivated, firmly established and has escaped from cultivation throughout the tropics and subtropics and in most of the main islands of Polynesia, Micronesia and Melanesia. Wedelia is out-of-control on the atolls of Kiribati, Tuvalu, Tokelau and the Tuamotus and the limestone island of Niue; and has rampantly spread into grazing areas, national parks, conservation areas, sensitive offshore islands, mangroves, swamps, towns, villages, and along rivers, coastlines and roads in Fiji, Palau, Pohnpei, Tahiti, New Caledonia and Papua New Guinea. Most attempts to control or eradicate it have failed, some at considerable cost. It is suggested that wedelia should be immediately declared a serious noxious weed, should be restricted from introduction into new islands and habitats, and, where possible, eradicated from islands, habitats where it is yet to gain a firm foothold. If action is taken NOW, islands and communities throughout the Pacific can prevent the spread of Wedelia BEFORE it replaces extensive areas of indigenous, where it out-competes plants of considerable ecological and cultural importance. This conclusion is based on my studies of Wedelia over the past 30 years in most of the countries and territories of the Pacific

The prevalence and risk factors for phantom limb pain: a cross-sectional survey

Abstract Background We previously performed a systematic review and meta-analysis which revealed a Phantom Limb Pain (PLP) prevalence estimate of 64% [95% CI: 60.01–68.1]. The prevalence estimates varied significantly between developed and developing countries. Remarkably, there is limited evidence on the prevalence of PLP and associated risk factors in African populations. Methods Adults who had undergone limb amputations between January 2018 and October 2022 were recruited from healthcare facilities in the Western and Eastern Cape Provinces. We excluded individuals with auditory or speech impairments that hindered clear communication via telephone. Data on the prevalence and risk factors for PLP were collected telephonically from consenting and eligible participants. The prevalence of PLP was expressed as a percentage with a 95% confidence interval. The associations between PLP and risk factors for PLP were tested using univariate and multivariable logistic regression analyses. The strength of association was calculated using the Odds Ratio where association was confirmed. Results The overall PLP prevalence was 71.73% [95% CI: 65.45–77.46]. Persistent pre-operative pain, residual limb pain, and non-painful phantom limb sensations were identified as risk factors for PLP. Conclusion This study revealed a high prevalence of PLP. The use of effective treatments targeting pre-amputation pain may yield more effective and targeted pre-amputation care, leading to improved quality of life after amputation