Publications from CRPS Registry Research Studies
The CRPS Registry is a long-term research study in its own right. Researchers from other organisations can also use the Registry to recruit people for their own studies (subject to approval from the Registry Steering Committee). Publications that have resulted from studies related to the Registry are listed below.
Abstracts (overviews) of all research papers can be accessed using the following links, but please note that some will require an active subscription to the relevant journal in order to access the full publication.
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UWE Bristol academics developing sensory training system for Complex Regional Pain Syndrome - blog published online in July 2022 via the University of the West of England's website. This gives an overview of the Sensory Training System (STS) research pilot study.
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A Delphi study to define core clinical outcomes for inclusion in a complex regional pain syndrome international research registry and data bank - published online in PAIN, July 2022. A minimum set of CRPS patient-reported outcomes has been agreed for inclusion in a future international registry. This paper outlines the work undertaken by the COMPACT-C research team to identify a complementary set of core clinical outcomes. Clinicians and researchers from the international CRPS community informed the content of a two-round electronic Delphi survey.
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'Gaming' device aims to help with persistent pain - blog published online in March 2022 via the University of Leeds Medical Technologies Centre website. This gives an overview of the Sensory Training System (STS) research pilot study.
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Visual illusions modulate body perception disturbance and pain in Complex Regional Pain Syndrome: A randomized trial - published online in the European Journal of Pain, March 2021. Effective treatment of longstanding CRPS is a challenge, as mechanisms that cause the condition remain elusive. People with CRPS frequently report distorted subjective perceptions of their affected limb. Previous research has shown evidence of pain reduction when the affected limb is visually altered in size. Researchers hypothesized that using virtual reality and altering the hand image to match the patient's desired hand appearance would improve body perception disturbance and pain. Also, repeated exposure would maintain any therapeutic effect.
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Prism adaptation treatment for upper-limb Complex Regional Pain Syndrome: a double-blind randomized controlled trial - published in PAIN, February 2021 (previously published online in August 2020). Three previous unblinded, uncontrolled studies showed pain relief following treatment with prism adaptation. To provide a robust test of its effectiveness for CRPS, researchers conducted a double-blind randomised controlled trial of prism adaptation for unilateral upper-limb CRPS type I. Overall, CRPS severity significantly decreased over time for both groups, but researchers found no benefits of prism adaptation beyond sham treatment. Findings from this study do not support the efficacy of prism adaptation treatment for relieving upper-limb CRPS type I.
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Altered updating of bodily and spatial representations after tool-use in complex regional pain syndrome - published in PAIN, July 2020. This study tested the hypothesis that people with CRPS have problems updating bodily and spatial representations. Tool-use tasks were completed by 36 people with upper or lower limb CRPS and 36 pain-free controls. The effects of hand temperature whilst using crossed/uncrossed hands and tools were also tested.
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Bodily changes and sensory sensitivity in Complex Regional Pain Syndrome and fibromyalgia - published in PAIN, June 2020 (previously published online in February 2020). In addition to symptoms in the diagnostic criteria, patients can report changes to vision and other sensations or bodily functions. It is unclear whether these are greater than would be expected due to normal ageing, living with chronic pain generally, or common co-morbidities of chronic pain such as depression or anxiety. An online survey evaluated the frequencies and types of self-reported somatic symptoms, bodily changes, and sensory sensitivity in respondents with CRPS, fibromyalgia, and both CRPS and fibromyalgia compared to respondents with other chronic pain conditions and pain-free controls.
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Pain Reduction by Inducing Sensory-Motor Adaptation in Complex Regional Pain Syndrome (CRPS PRISMA: Protocol for a Double-blind Randomized Controlled Trial - published in BMC Neurology, February 2020. Prism Adaptation is a behavioural intervention targeted at reducing attention deficits in post-stroke hemispatial neglect. It also appears to reduce pain and other CRPS symptoms, however, these therapeutic effects have been demonstrated only in small unblinded studies. This paper describes the protocol for an ongoing study that will evaluate the efficacy of Prism Adaptation treatment for CRPS. The secondary aims of the study are to examine the relationships between neuropsychological changes and clinical manifestations of CRPS, as well as symptom improvement.
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Sub-optimal learning of tactile-spatial predictions in patients with Complex Regional Pain Syndrome - published in PAIN, February 2020 (previously published online in October 2019). In CRPS, tactile sensory deficits have motivated the therapeutic use of sensory discrimination training. However, the hierarchical organisation of the brain is such that low-level sensory processing can be dynamically influenced by higher-level knowledge, e.g. knowledge learnt from statistical regularities in the environment. It is unknown whether the learning of such statistical regularities is impaired in CRPS. This study employed a hierarchical Bayesian model of predictive coding to investigate statistical learning of tactile-spatial predictions in CRPS.
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A multi-centre study to explore the feasibility and acceptability of collecting data for complex regional pain syndrome clinical studies using a core measurement set: study protocol - published in Musculoskeletal Care, July 2019. This paper relates to the latest phase of the international COMPACT study. It explains the process for testing the collection of outcome measurement data using the recommended patient-reported questionnaire set, as well as developing an electronic system to collect and manage the data.
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Cortical reorganisation in CRPS and digit misperception - a high density EEG study. Conference poster presentation and research project that formed part of a doctoral thesis in 2018. Painless stimuli was delivered to the fingertips by custom-made hand boxes and EEG data were collected. When undertaking a behavioural task, CRPS patients had significantly reduced accuracy and prolonged reaction time in the affected side compared to healthy volunteers.
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When can you say you are well again? How do people with Complex Regional Pain Syndrome define recovery? - blog published online in April 2018 via the Body in Mind website. This gives an overview of the international Recovery study and the key findings.
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Are you better? A multi-centre study exploring the patients definition of recovery from Complex Regional Pain Syndrome - published in the European Journal of Pain, December 2017. An in-depth analysis of the international Recovery study, which aimed to define recovery from the patients' perspective and to better understand their priorities for treatment approaches. The data showed that a small number of themes are of highest importance to CRPS patients' definition of recovery. Patients want their pain, movement restriction and reliance on medication to be addressed, above all other factors. These factors should therefore be foremost concerns for future treatment and rehabilitation programmes.
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Low-dose intravenous immunoglobulin treatment for long-standing Complex Regional Pain Syndrome, a randomised placebo-controlled phase III multi-centre trial - published in Annals of Internal Medicine, October 2017. This paper focuses on the LIPs trial, which explored the effectiveness of a specific drug treatment for the reduction of pain. The study found that low-dose immunoglobulin was not effective in relieving pain in patients with moderate to severe CRPS of 1–5 years’ duration. Better drug treatments for long-standing CRPS are urgently required.
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Data comparison made easy! A Core Outcome Measurement set for complex regional PAin syndrome Clinical sTudies (COMPACT) - a blog published online in September 2017 via the Body in Mind website. An overview of the process to agree an international minimum core set of standardised outcome measures for use in future CRPS clinical research.
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Recommendations for a first Core Outcome Measurement set for complex regional PAin syndrome Clinical sTudies (COMPACT) - published in PAIN (IASP research journal), 2017. An in-depth analysis of the development of an agreed core measurement set for CRPS, using patient-reported outcomes measures. This was the first phase of the international COMPACT study, and the feasibility of collecting data using this questionnaire set is currently being tested.
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Establishing the characteristics of patients with chronic Complex Regional Pain Syndrome: the value of the CRPS-UK Registry - published in the British Journal of Pain, 2015. This was the first paper written specifically about the Registry, outlining its purpose and development. The article also assesses the validity of the data and describes the characteristics of a sample of the UK CRPS population.