Neuropathic pain: an updated grading system for research and clinical practice.
The redefinition of neuropathic pain as "pain arising as a direct consequence of a lesion or disease affecting the somatosensory system," which was suggested by the International Association for the Study of Pain (IASP) Special Interest Group on Neuropathic Pain (NeuPSIG) in 2008, has been widely accepted. In contrast, the proposed grading system of possible, probable, and definite neuropathic pain from 2008 has been used to a lesser extent. Here, we report a citation analysis of the original NeuPSIG grading paper of 2008, followed by an analysis of its use by an expert panel and recommendations for an improved grading system. As of February, 2015, 608 eligible articles in Scopus cited the paper, 414 of which cited the neuropathic pain definition. Of 220 clinical studies citing the paper, 56 had used the grading system. The percentage using the grading system increased from 5% in 2009 to 30% in 2014. Obstacles to a wider use of the grading system were identified, including (1) questions about the relative significance of confirmatory tests, (2) the role of screening tools, and (3) uncertainties about what is considered a neuroanatomically plausible pain distribution. Here, we present a revised grading system with an adjusted order, better reflecting clinical practice, improvements in the specifications, and a word of caution that even the "definite" level of neuropathic pain does not always indicate causality. In addition, we add a table illustrating the area of pain and sensory abnormalities in common neuropathic pain conditions and propose areas for further research.
Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
Nanna B
NB
Finnerup
Division of Clinical and Translational Research, Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, USA.
Simon
S
Haroutounian
Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Peter
P
Kamerman
Division of Neurological Pain Research and Therapy, Department of Neurology, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Kiel, Germany.
Ralf
R
Baron
Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford, United Kingdom.
David L H
DLH
Bennett
INSERM U-987, Centre d'Evaluation et de Traitement de la Douleur, CHU Ambroise Paré, Boulogne-Billancourt, France.|Université Versailles-Saint-Quentin, Versailles, France.
Didier
D
Bouhassira
Department of Neurology and Psychiatry, Sapienza University, Rome, Italy.
Giorgio
G
Cruccu
Autonomic and Peripheral Nerve Laboratory, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Roy
R
Freeman
Department of Pain Management and Research, Division of Emergencies and Critical Care, Oslo University Hospital, Oslo, Norway.|Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
Per
P
Hansson
Pain Research Institute, Neuroscience Research Centre, The Walton Centre NHS Foundation Trust, Liverpool, United Kingdom.
Turo
T
Nurmikko
Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA.
Srinivasa N
SN
Raja
Pain Research, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, United Kingdom.|Pain Medicine, Chelsea and Westminster Hospital NHS Foundation Trust, London, United Kingdom.
Andrew S C
ASC
Rice
Neuroscience Technologies, Ltd, Barcelona, Spain.
Jordi
J
Serra
Ninewells Hospital and Medical School, Division of Population Health Sciences, School of Medicine, University of Dundee, Dundee, Scotland.
Blair H
BH
Smith
Chair of Neurophysiology, Center of Biomedicine and Medical Technology Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany.
Rolf-Detlef
RD
Treede
Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.|Department of Neurology, Aarhus University Hospital, Aarhus, Denmark.
Troels S
TS
Jensen
D006801:Humans; D009437:Neuralgia / Q000175:diagnosis* / Q000503:physiopathology; D059408:Pain Management; D010147:Pain Measurement / Q000592:standards*; D012106:Research; D011795:Surveys and Questionnaires