title: Abnormal Pain Response to Visual Feedback During Cervical Movements in Chronic Whiplash: An Experimental Study.
abstract: Whiplash-associated disorders (WAD) are a debilitating condition. In chronic WAD, sensorimotor incongruence exacerbates symptoms. Sensorimotor incongruence occurs when somatosensory input and predicted motor output are in conflict, which can trigger pain. On the other hand, there is evidence that visual feedback can decrease pain in certain chronic pain conditions. Therefore, the aim of this study was to examine the effect of visual feedback and sensorimotor incongruence on pain thresholds in chronic WAD.
  
  
  
  Sixty-four participants (healthy controls and patients with chronic WAD) were subjected to six experimental conditions. Participants watched correct real-time or modified visual feedback of the neck or hand (without movement as well as during repetitive neck lateroflexion). Sensorimotor incongruence was induced by manipulating visual feedback. Pressure pain thresholds were measured at baseline and during each condition.
  
  
  
  Marked between-group differences were observed. Visual feedback of the neck-correct or modified-did not influence pain thresholds in chronic WAD. In contrast, healthy controls had significantly higher pain thresholds when provided with the correct or modified visual feedback. When a movement of the neck was added during visual feedback, patients with chronic WAD showed no significant difference in pain thresholds, while an increase in pain thresholds was found in the healthy control group.
  
  
  
  In contrast to the healthy controls, visual feedback and sensorimotor incongruence did not alter pain thresholds in patients with chronic WAD. These findings suggest an abnormal pain response to visual feedback and somatosensory incongruence as well as failing mechanisms of pain inhibition in chronic WAD.
authors.affiliation: Pain in Motion Research Group, Departments of Human Physiology and Physiotherapy, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel (VUB), Brussels, Belgium.|Faculty of Medicine and Health Sciences, Born Bunge Institute, University of Antwerp (UA), Antwerp, Belgium.
authors.forename: Margot
authors.initials: M
authors.lastname: De Kooning
authors.affiliation: Pain in Motion Research Group, Departments of Human Physiology and Physiotherapy, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel (VUB), Brussels, Belgium.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Daenen
authors.affiliation: praktijk-hildebessems, Belgium.
authors.forename: Sam
authors.initials: S
authors.lastname: Verhelpen
authors.affiliation: Pain in Motion Research Group, Departments of Human Physiology and Physiotherapy, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel (VUB), Brussels, Belgium.|Department of Physiotherapy, Rotterdam University of Applied Sciences, The Netherlands.
authors.forename: Sanneke
authors.initials: S
authors.lastname: Don
authors.affiliation: Pain in Motion Research Group, Departments of Human Physiology and Physiotherapy, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel (VUB), Brussels, Belgium.|Department of Physiotherapy, Rotterdam University of Applied Sciences, The Netherlands.
authors.forename: Lennard
authors.initials: L
authors.lastname: Voogt
authors.affiliation: Pain in Motion Research Group, Departments of Human Physiology and Physiotherapy, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel (VUB), Brussels, Belgium.|Pain in Motion Research Group, Department of Rehabilitation Sciences and Physiotherapy (REVAKI), Faculty of Medicine and Health Sciences, University of Antwerp (UA), Antwerp, Belgium.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Roussel
authors.affiliation: Pain in Motion Research Group, Departments of Human Physiology and Physiotherapy, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel (VUB), Brussels, Belgium.
authors.forename: Kelly
authors.initials: K
authors.lastname: Ickmans
authors.affiliation: Centrum Letsel & Schade, Belgium.
authors.forename: Michel
authors.initials: M
authors.lastname: Van Loo
authors.affiliation: praktijk-hildebessems, Belgium.|Department of Neurology, Antwerp University Hospital, Antwerp, Belgium.
authors.forename: Patrick
authors.initials: P
authors.lastname: Cras
authors.affiliation: Pain in Motion Research Group, Departments of Human Physiology and Physiotherapy, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel (VUB), Brussels, Belgium.
authors.forename: Jo
authors.initials: J
authors.lastname: Nijs
mesh_terms: D000328:Adult; D002574:Cervical Vertebrae / Q000503:physiopathology*; D059350:Chronic Pain / Q000523:psychology*; D056228:Feedback, Sensory; D005260:Female; D006225:Hand; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement; D009333:Neck; D010147:Pain Measurement; D017288:Pain Threshold; D014911:Whiplash Injuries / Q000503:physiopathology / Q000523:psychology*
keywords: chronic whiplash-associated disorders; pain modulation; pressure pain threshold; sensorimotor incongruence; visual feedback