Matthew R. Mulvey

Fibromyalgia: mechanisms and potential impact of the ACR 2010 classification criteria

Fibromyalgia is a disorder characterized by chronic widespread pain in the presence of widespread tenderness, and multiple somatic symptoms. Since the publication of the American College of Rheumatology (ACR) 1990 classification criteria for fibromyalgia, research has proliferated and, in a relatively short period, investigators have begun to unravel the etiology and long-term impact of this complex condition. Although the ACR 1990 criteria have been central to fibromyalgia research during the past two decades, a number of practical and philosophical objections have been raised in relation to them. Principally these objections have centered on the use (or lack thereof) of the tender point examination, the lack of consideration of associated symptoms, and the observation that fibromyalgia might represent the extreme end of a pain continuum. In developing the ACR 2010 criteria, experts have sought to address these issues and to simplify clinical diagnosis. An implicit aim was to facilitate more rigorous study of etiology. The purpose of this Review is to summarize research to date that has described the epidemiology, pathology and clinical course of fibromyalgia, and to assess the probable impact of the ACR 2010 criteria on future research efforts.

Modest Association of Joint Hypermobility With Disabling and Limiting Musculoskeletal Pain: Results From a Large‐Scale General Population–Based Survey

To determine the population prevalence of joint hypermobility (JH) and to test the hypothesis that JH would be associated with reporting musculoskeletal pain.

The use of transcutaneous electrical nerve stimulation (TENS) to aid perceptual embodiment of prosthetic limbs

Integration of prosthetic limb awareness into body schema is likely to aid manual control of the prosthesis. Physiotherapists and prosthetists use techniques to generate mechanical, visual and/or auditory feedback related to stimulation of the stump and proximal residual limb to improve prosthetic limb awareness. Electrical stimulation of afferent nerves using implanted electrodes can generate sensations of touch, joint movement, and position, in the missing, phantom limbs of amputees. We report here a novel hypothesis that non-invasive transcutaneous electrical nerve stimulation (TENS) could be used to facilitate the process of perceptual embodiment of a prosthesis into the body schema of amputees. Using a modified version of the rubber hand illusion (RHI), we have found that TENS paraesthesiae can be made to feel like it is emanating from a prosthetic hand in healthy participants with intact limbs. In addition, participants reported perceptual embodiment of the prosthetic hand into their body schema, i.e. it felt as if it is part of their body. We predict that projecting TENS paraesthesiae into the prosthetic limb(s) of amputees will provide sufficient sensory input to facilitate perceptual embodiment. This could prove to be a simple and inexpensive training aid to improve ambulation and prosthesis success.

Transcutaneous Electrical Nerve Stimulation for Phantom Pain and Stump Pain in Adult Amputees

Abstract  Following amputation, 50% to 90% of individuals experience phantom and/or stump pain. Transcutaneous electrical nerve stimulation (TENS) may prove to be a useful adjunct analgesic intervention, although a recent systematic review was unable to judge effectiveness owing to lack of quality evidence. The aim of this pilot study was to gather data on the effect of TENS on phantom pain and stump pain at rest and on movement. Ten individuals with a transtibial amputation and persistent moderate‐to‐severe phantom and/or stump pain were recruited. Inclusion criteria was a baseline pain score of ≥3 using 0 to 10 numerical rating scale (NRS). TENS was applied for 60 minutes to generate a strong but comfortable TENS sensation at the site of stump pain or projected into the site of phantom pain. Outcomes at rest and on movement before and during TENS at 30 minutes and 60 minutes were changes in the intensities of pain, nonpainful phantom sensation, and prosthesis embodiment. Mean (SD) pain intensity scores were reduced by 1.8 (1.6) at rest (P < 0.05) and 3.9 (1.9) on movement (P < 0.05) after 60 minutes of TENS. For five participants, it was possible to project TENS sensation into the phantom limb by placing the electrodes over transected afferent nerves. Nonpainful phantom sensations and prosthesis embodiment remained unchanged. This study has demonstrated that TENS has potential for reducing phantom pain and stump pain at rest and on movement. Projecting TENS sensation into the phantom limb might facilitate perceptual embodiment of prosthetic limbs. The findings support the delivery of a feasibility trial.

Confirming neuropathic pain in cancer patients: applying the NeuPSIG grading system in clinical practice and clinical research

1. Introduction and epidemiologyPain is frequently a presenting symptom of cancer. Around 50%of patients have pain at diagnosis, while up to 75% of patients willexperience pain if their cancer becomes advanced and progressive[29]. Cancer patients experience 2 distinct pains, on average, and20% of these pains are of neuropathic origin; however, when thedefinition is widened to include mixed neuropathic-nociceptivepain, approximately 40% of cancer patients are affected by neuro-pathic pain (NP) [4].The pains experienced by cancer patients are heterogeneous,and vary depending on pathophysiology and duration/stage of dis-ease, though higher pain intensity is associated with the presenceof NP [7]. NP in general is not a single condition but represents asyndrome,which can be thought of as a collectionof specific symp-toms and signs with multiple underlying aetiologies [2]. Theaetiology of pain in cancer patients is complex and is often a mixof inflammatory and neuropathic mechanisms that evolve overtime as the tumour progresses [28]. The picture is further compli-cated because NP symptoms and signs frequently exist as aspectrum and therefore, the clinical question is not ‘‘does mypatient have neuropathic or nociceptive pain?’’, but rather, ‘‘is thispain predominantly neuropathic or nociceptive in origin?’’ [5].Nevertheless, NP in cancer patients is conventionally categorisedas disease-related, treatment-related, or comorbid [21]. Abouttwo-thirds of NP in cancer patients is disease-related (neuropathiccancer pain [NCP]), while cancer treatments, such as surgery orchemotherapy, account for 20% of NP, and comorbid diseases areresponsible for a further 10%–15% [4].NP in cancer patients is associated with increased oncologicaltreatment, greater analgesic requirements (especially strongopioids and adjuvant analgesia), decreased physical, cognitive,and social functioning, and greater impact on daily living [22].Sadly, however, undertreatment of cancer pain is common and isrelated to a combination of factors, including fears around usingopioids, poor assessment of pain, and inadequate identification ofunderlying pathophysiology [9]. This is consistent with the man-agement of noncancer NP, where undertreatment is also common[26]. The difficulty in identifying NP in cancer patients is illustratedby the development of the Edmonton Classification System forCancer Pain. The original version categorised cancer pain as ‘‘noci-ceptive,’’ ‘‘neuropathic,’’ ‘‘mixed,’’ and ‘‘unclassified’’ [11]. The up-dated version has reduced the classification to a dichotomousyes/no response to denote the presence or absence of NP basedon the clinician opinion [10].There is clearly uncertainty surrounding the classification anddiagnosis of NP in cancer patients. Poorer health outcomes andgreater disability associated with NP in both cancer and noncancerpopulations suggest that there is an inherent disadvantage con-ferred by NP mechanisms regardless of aetiology [25]. Therefore,effectively assessing and diagnosing NP in cancer patients is crucialbefore improvements in treatments and outcomes can occur. Inthis topical review, we examine the reliability of the current ap-proach to the assessment of NP in cancer patients and propose astandardised assessment protocol for confirming neuropathic painin cancer patients by adapting existing guidance [8,14,27].2. Reliability of current assessment of neuropathic painDespite the existence of a definition for NP since 1994 [20],there has been little consensus on diagnostic criteria until very re-cently. In 2008, Treede et al. [27] revised the definition of NP to‘‘painarisingas a direct consequenceof a lesion or diseaseaffectingthe somatosensory nervous system,’’ which was adopted by theInternational Association for the Study of Pain (IASP) in 2011[17]. Treede et al. also proposed a grading system to classify the

Perceptual embodiment of prosthetic limbs by transcutaneous electrical nerve stimulation.

Objectives:  In able‐bodied participants, it is possible to induce a sense of perceptual embodiment in an artificial hand using a visual‐tactile illusion. In amputee patients, electrical stimulation of sensory afferents using transcutaneous electrical nerve stimulation (TENS) has been shown to generate somatic sensations in an amputees phantom limb(s). However, the effects of TENS on the perceptual embodiment of an artificial limb are not known. Our objective was to investigate the effects of TENS on the perceptual embodiment of an artificial limb in fully intact able‐bodied participants.

The role of screening tools in diagnosing neuropathic pain

Neuropathic pain affects 6-8% of the general adult population. It is reported by 27% of chronic pain patients and 40% of cancer patients, yet there is no standardized diagnostic test for neuropathic pain. A number of screening tools have been developed based on verbal pain descriptors, with or without limited clinical examination, to identify individuals with neuropathic pain. Over the past decade these neuropathic pain screening tools have been validated in a wide range of pain populations, as well as translated into many languages, to discriminate between neuropathic and non-neuropathic pain. We describe here the five most commonly used neuropathic pain screening tools and discuss current assessment guidelines, the use of screening tools in novel clinical contexts and their potential use in personalized therapy.

Opioid prescribing for patients with cancer in the last year of life: a longitudinal population cohort study.

Abstract We linked UK cancer registry data with the corresponding electronic primary care medical records of 6080 patients who died of cancer over a 7-year period in a large United Kingdom city. We extracted all prescriptions for analgesics issued to each patient in the linked cohort during the 12 months before death and analysed the extent and duration of strong opioid treatment with clinical and patient characteristics. Strong opioids were prescribed for 48% of patients in the last year of life. Median interval between first prescription of a strong opioid and death was 9 weeks (interquartile range 3-23). Strong opioid prescribing was not influenced by cancer type, duration of illness, or gender but was adversely influenced by older age. Compared with patients who died in a hospice, those who died in a hospital were 60% less likely to receive a strong opioid in primary care before admission (relative risk ratio 0.4, CI 0.3-0.5, P < 0.01). The study provides the first detailed analysis of the relatively late onset and short duration of strong opioid treatment in patients with cancer before death in a representative UK cohort. This pattern of prescribing does not match epidemiological data which point to earlier onset of pain. Although persistent undertreatment of cancer pain is well documented, this study suggests that strategies for earlier pain assessment and initiation of strong opioid treatment in community-based patients with cancer could help to improve pain outcomes.

Information and communication technology for managing pain in palliative care: a review of the literature

Background Information and communication technology (ICT) systems are being developed for electronic symptom reporting across different stages of the cancer trajectory with research in palliative care at an early stage. Aim/design This paper presents the first systematic search of the literature to review existing ICT systems intended to support management of pain in palliative care patients with cancer. The review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for systematic reviews and meta-analyses. Data sources Four databases (Embase, MEDLINE, PsycINFO and Healthcare Management Information Consortium) from 1990 to December 2012 were searched, with exclusion of papers based on their description of ICT systems and language used. Results 24 articles met the inclusion criteria, many of which reported the use of non-experimental research designs. Studies were identified at different stages of development with no systems having reached implementation. Most systems captured pain as part of quality-of-life measurement with wide variation in approaches to pain assessment. Conclusions ICT systems for symptom reporting are emerging in the palliative care context. Future development of ICT systems need to increase the quality and scale of development work, consider how recommendations for pain measurement can be integrated and explore how to effectively use system feedback with patients.

AAPT Diagnostic Criteria for Chronic Cancer Pain Conditions

Chronic cancer pain is a serious complication of malignancy or its treatment. Currently, no comprehensive, universally accepted cancer pain classification system exists. Clarity in classification of common cancer pain syndromes would improve clinical assessment and management. Moreover, an evidence-based taxonomy would enhance cancer pain research efforts by providing consistent diagnostic criteria, ensuring comparability across clinical trials. As part of a collaborative effort between the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) and the American Pain Society (APS), the ACTTION-APS Pain Taxonomy initiative worked to develop the characteristics of an optimal diagnostic system. After the establishment of these characteristics, a working group consisting of clinicians and clinical and basic scientists with expertise in cancer and cancer-related pain was convened to generate core diagnostic criteria for an illustrative sample of 3 chronic pain syndromes associated with cancer (ie, bone pain and pancreatic cancer pain as models of pain related to a tumor) or its treatment (ie, chemotherapy-induced peripheral neuropathy). A systematic review and synthesis was conducted to provide evidence for the dimensions that comprise this cancer pain taxonomy. Future efforts will subject these diagnostic categories and criteria to systematic empirical evaluation of their feasibility, reliability, and validity and extension to other cancer-related pain syndromes.