Skip to main content
placeholder image

Fine-grained mapping of cortical somatotopies in chronic complex regional pain syndrome

Journal Article


Download full-text (Open Access)

Abstract


  • It has long been thought that severe chronic pain conditions, such as complex regional pain syndrome (CRPS), are not only associated with, but even maintained by a reorganization of the somatotopic representation of the affected limb in primary somatosensory cortex (S1). This notion has driven treatments that aim to restore S1 representations in CRPS patients, such as sensory discrimination training and mirror therapy. However, this notion is based on both indirect and incomplete evidence obtained with imaging methods with low spatial resolution. Here, we used fMRI to characterize the S1 representation of the affected and unaffected hand in humans (of either sex) with unilateral CRPS. The cortical area, location, and geometry of the S1 representation of the CRPS hand were largely comparable with those of both the unaffected hand and healthy controls. We found no differential relation between affected versus unaffected hand map measures and clinical measures (pain severity, upper limb disability, disease duration). Thus, if any map reorganization occurs, it does not appear to be directly related to pain and disease severity. These findings compel us to reconsider the cortical mechanisms underlying CRPS and the rationale for interventions that aim to "restore" somatotopic representations to treat pain.SIGNIFICANCE STATEMENT This study shows that the spatial map of the fingers in somatosensory cortex is largely preserved in chronic complex regional pain syndrome (CRPS). These findings challenge the treatment rationale for restoring somatotopic representations in complex regional pain syndrome patients.

UOW Authors


  •   Mancini, Flavia (external author)
  •   Wang, Audrey (external author)
  •   Schira, Mark
  •   Isherwood, Zoey J. (external author)
  •   McAuley, James (external author)
  •   Iannetti, Giandomenico (external author)
  •   Sereno, Martin (external author)
  •   Moseley, G (external author)
  •   Rae, Caroline (external author)

Publication Date


  • 2019

Citation


  • Mancini, F., Wang, A. P., Schira, M. M., Isherwood, Z. J., McAuley, J. H., Iannetti, G. D., Sereno, M. I., Moseley, G. Lorimer. & Rae, C. D. (2019). Fine-grained mapping of cortical somatotopies in chronic complex regional pain syndrome. The Journal of Neuroscience, 39 (46), 9185-9196.

Scopus Eid


  • 2-s2.0-85074965276

Ro Full-text Url


  • https://ro.uow.edu.au/cgi/viewcontent.cgi?article=5663&context=sspapers

Ro Metadata Url


  • http://ro.uow.edu.au/sspapers/4590

Number Of Pages


  • 11

Start Page


  • 9185

End Page


  • 9196

Volume


  • 39

Issue


  • 46

Place Of Publication


  • United States

Abstract


  • It has long been thought that severe chronic pain conditions, such as complex regional pain syndrome (CRPS), are not only associated with, but even maintained by a reorganization of the somatotopic representation of the affected limb in primary somatosensory cortex (S1). This notion has driven treatments that aim to restore S1 representations in CRPS patients, such as sensory discrimination training and mirror therapy. However, this notion is based on both indirect and incomplete evidence obtained with imaging methods with low spatial resolution. Here, we used fMRI to characterize the S1 representation of the affected and unaffected hand in humans (of either sex) with unilateral CRPS. The cortical area, location, and geometry of the S1 representation of the CRPS hand were largely comparable with those of both the unaffected hand and healthy controls. We found no differential relation between affected versus unaffected hand map measures and clinical measures (pain severity, upper limb disability, disease duration). Thus, if any map reorganization occurs, it does not appear to be directly related to pain and disease severity. These findings compel us to reconsider the cortical mechanisms underlying CRPS and the rationale for interventions that aim to "restore" somatotopic representations to treat pain.SIGNIFICANCE STATEMENT This study shows that the spatial map of the fingers in somatosensory cortex is largely preserved in chronic complex regional pain syndrome (CRPS). These findings challenge the treatment rationale for restoring somatotopic representations in complex regional pain syndrome patients.

UOW Authors


  •   Mancini, Flavia (external author)
  •   Wang, Audrey (external author)
  •   Schira, Mark
  •   Isherwood, Zoey J. (external author)
  •   McAuley, James (external author)
  •   Iannetti, Giandomenico (external author)
  •   Sereno, Martin (external author)
  •   Moseley, G (external author)
  •   Rae, Caroline (external author)

Publication Date


  • 2019

Citation


  • Mancini, F., Wang, A. P., Schira, M. M., Isherwood, Z. J., McAuley, J. H., Iannetti, G. D., Sereno, M. I., Moseley, G. Lorimer. & Rae, C. D. (2019). Fine-grained mapping of cortical somatotopies in chronic complex regional pain syndrome. The Journal of Neuroscience, 39 (46), 9185-9196.

Scopus Eid


  • 2-s2.0-85074965276

Ro Full-text Url


  • https://ro.uow.edu.au/cgi/viewcontent.cgi?article=5663&context=sspapers

Ro Metadata Url


  • http://ro.uow.edu.au/sspapers/4590

Number Of Pages


  • 11

Start Page


  • 9185

End Page


  • 9196

Volume


  • 39

Issue


  • 46

Place Of Publication


  • United States