title: Expanded Distribution of Pain as a Sign of Central Sensitization in Individuals With Symptomatic Knee Osteoarthritis.
abstract: Expanded distribution of pain is considered a sign of central sensitization (CS). The relationship between recording of symptoms and CS in people with knee osteoarthritis (OA) has been poorly investigated.
  
  
  
  The aim of this study was to examine whether the area of pain assessed using pain drawings relates to CS and clinical symptoms in people with knee OA.
  
  
  
  This was a cross-sectional study.
  
  
  
  Fifty-three people with knee OA scheduled to undergo primary total knee arthroplasty were studied. All participants completed pain drawings using a novel digital device, completed self-administration questionnaires, and were assessed by quantitative sensory testing. Pain frequency maps were generated separately for women and men. Spearman correlation coefficients were computed to reveal possible correlations between the area of pain and quantitative sensory testing and clinical symptoms.
  
  
  
  Pain frequency maps revealed enlarged areas of pain, especially in women. Enlarged areas of pain were associated with higher knee pain severity (rs=.325, P<.05) and stiffness (rs=.341, P<.05), lower pressure pain thresholds at the knee (rs=-.306, P<.05) and epicondyle (rs=-.308, P<.05), and higher scores with the Central Sensitization Inventory (rs=.456, P<.01). No significant associations were observed between the area of pain and the remaining clinical symptoms and measures of CS.
  
  
  
  Firm conclusions about the predictive role of pain drawings cannot be drawn. Further evaluation of the reliability and validity of pain area extracted from pain drawings in people with knee OA is needed.
  
  
  
  Expanded distribution of pain was correlated with some measures of CS in individuals with knee OA. Pain drawings may constitute an easy way for the early identification of CS in people with knee OA, but further research is needed.
authors.affiliation: E. Lluch Girbés, PT, PhD, Department of Physical Therapy, University of Valencia, Gascó Oliag 5, 46010 Valencia, Spain; Departments of Human Physiology and Rehabilitation Sciences, Faculty of Physical Education & Physiotherapy, Vrije Universiteit Brussels, Brussels, Belgium; and Pain in Motion International Research Group, Brussels, Belgium. enrique.lluch@uv.es.
authors.forename: Enrique
authors.initials: E
authors.lastname: Lluch Girbés
authors.affiliation: L. Dueñas, PT, PhD, Department of Physical Therapy, University of Valencia.
authors.forename: Lirios
authors.initials: L
authors.lastname: Dueñas
authors.affiliation: M. Barbero, PT, PhD, Department of Business, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland (SUPSI), Manno, Switzerland.
authors.forename: Marco
authors.initials: M
authors.lastname: Barbero
authors.affiliation: D. Falla, PT, PhD, School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom, and Pain Clinic, Center for Anesthesiology, Emergency and Intensive Care Medicine, University Hospital Göttingen, Göttingen, Germany.
authors.forename: Deborah
authors.initials: D
authors.lastname: Falla
authors.affiliation: I.A.C. Baert, PT, PhD, Pain in Motion International Research Group and MovAnt, Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.
authors.forename: Isabel A C
authors.initials: IA
authors.lastname: Baert
authors.affiliation: M. Meeus, PT, PhD, Pain in Motion International Research Group and MovAnt, Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, University of Antwerp, and Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium.
authors.forename: Mira
authors.initials: M
authors.lastname: Meeus
authors.affiliation: J. Sánchez-Frutos, MD, PhD, Department of Physical Therapy, University of Valencia.
authors.forename: José
authors.initials: J
authors.lastname: Sánchez-Frutos
authors.affiliation: L. Aguilella, MD, PhD, Orthopaedic Surgery Service, Hospital Universitario de La Ribera, Alzira, Spain.
authors.forename: Luis
authors.initials: L
authors.lastname: Aguilella
authors.affiliation: J. Nijs, PT, PhD, Departments of Human Physiology and Rehabilitation Sciences, Faculty of Physical Education & Physiotherapy, Vrije Universiteit Brussels, and Pain in Motion International Research Group.
authors.forename: Jo
authors.initials: J
authors.lastname: Nijs
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D059333:Central Nervous System Sensitization; D059350:Chronic Pain / Q000209:etiology / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D003626:Data Display; D005080:Exercise Test; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D059352:Musculoskeletal Pain / Q000209:etiology / Q000503:physiopathology*; D020370:Osteoarthritis, Knee / Q000150:complications / Q000503:physiopathology*; D010147:Pain Measurement; D016059:Range of Motion, Articular; D057566:Self Report