Format

Send to

Choose Destination
Eur J Pain. 2011 Jan;15(1):17-22. doi: 10.1016/j.ejpain.2010.04.009. Epub 2010 Jun 8.

Pain and other symptoms of CRPS can be increased by ambiguous visual stimuli--an exploratory study.

Author information

1
Royal National Hospital for Rheumatic Diseases, Upper Borough Walls, Bath, United Kingdom. jane.hall@rnhrd.nhs.uk

Abstract

BACKGROUND:

Visual disturbance, visuo-spatial difficulties, and exacerbations of pain associated with these, have been reported by some patients with Complex Regional Pain Syndrome (CRPS).

AIMS:

We investigated the hypothesis that some visual stimuli (i.e. those which produce ambiguous perceptions) can induce pain and other somatic sensations in people with CRPS.

METHODS:

Thirty patients with CRPS, 33 with rheumatology conditions and 45 healthy controls viewed two images: a bistable spatial image and a control image. For each image participants recorded the frequency of percept change in 1 min and reported any changes in somatosensation.

RESULTS:

73% of patients with CRPS reported increases in pain and/or sensory disturbances including changes in perception of the affected limb, temperature and weight changes and feelings of disorientation after viewing the bistable image. Additionally, 13% of the CRPS group responded with striking worsening of their symptoms which necessitated task cessation. Subjects in the control groups did not report pain increases or somatic sensations.

CONCLUSIONS:

It is possible to worsen the pain suffered in CRPS, and to produce other somatic sensations, by means of a visual stimulus alone. This is a newly described finding. As a clinical and research tool, the experimental method provides a means to generate and exacerbate somaesthetic disturbances, including pain, without moving the affected limb and causing nociceptive interference. This may be particularly useful for brain imaging studies.

PMID:
20965133
DOI:
10.1016/j.ejpain.2010.04.009
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center