TY - JOUR
T1 - Central sensitization in spinal cord injured humans assessed by reflex receptive fields
AU - Biurrun Manresa, José Alberto
AU - Finnerup, Nanna Susanne Brix
AU - Johannesen, Inger Lauge
AU - Biering-Sørensen, Fin
AU - Jensen, Troels Staehelin
AU - Arendt-Nielsen, Lars
AU - Andersen, Ole Kæseler
N1 - Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
PY - 2014/2
Y1 - 2014/2
N2 - OBJECTIVE: To investigate the effects of central sensitization, elicited by intramuscular injection of capsaicin, by comparing the reflex receptive fields (RRF) of spinally-intact volunteers and spinal cord injured volunteers that present presensitized spinal nociceptive mechanisms.METHODS: Fifteen volunteers with complete spinal cord injury (SCI) and fourteen non-injured (NI) volunteers participated in the experiment. Repeated electrical stimulation was applied on eight sites on the foot sole to elicit the nociceptive withdrawal reflex (NWR). RRF were assessed before, 1min after and 60min after an intramuscular injection of capsaicin in the foot sole in order to induce central sensitization.RESULTS: Both groups presented RRF expansion and lowered NWR thresholds immediately after capsaicin injection, reflected by the enlargement of RRF sensitivity areas and RRF probability areas. Moreover, the topography of the RRF sensitivity and probability areas were significantly different in SCI volunteers compared to NI volunteers in terms of size and shape.CONCLUSIONS: SCI volunteers can develop central sensitization, despite adaptive/maladaptive changes in synaptic plasticity and lack of supraspinal control.SIGNIFICANCE: Protective plastic mechanisms may still be functional in SCI volunteers.
AB - OBJECTIVE: To investigate the effects of central sensitization, elicited by intramuscular injection of capsaicin, by comparing the reflex receptive fields (RRF) of spinally-intact volunteers and spinal cord injured volunteers that present presensitized spinal nociceptive mechanisms.METHODS: Fifteen volunteers with complete spinal cord injury (SCI) and fourteen non-injured (NI) volunteers participated in the experiment. Repeated electrical stimulation was applied on eight sites on the foot sole to elicit the nociceptive withdrawal reflex (NWR). RRF were assessed before, 1min after and 60min after an intramuscular injection of capsaicin in the foot sole in order to induce central sensitization.RESULTS: Both groups presented RRF expansion and lowered NWR thresholds immediately after capsaicin injection, reflected by the enlargement of RRF sensitivity areas and RRF probability areas. Moreover, the topography of the RRF sensitivity and probability areas were significantly different in SCI volunteers compared to NI volunteers in terms of size and shape.CONCLUSIONS: SCI volunteers can develop central sensitization, despite adaptive/maladaptive changes in synaptic plasticity and lack of supraspinal control.SIGNIFICANCE: Protective plastic mechanisms may still be functional in SCI volunteers.
KW - Adult
KW - Aged
KW - Capsaicin
KW - Central Nervous System Sensitization
KW - Electric Stimulation
KW - Electromyography
KW - Female
KW - Humans
KW - Male
KW - Middle Aged
KW - Nociceptors
KW - Pain Measurement
KW - Pain Threshold
KW - Reflex
KW - Sensory System Agents
KW - Spinal Cord Injuries
U2 - 10.1016/j.clinph.2013.06.186
DO - 10.1016/j.clinph.2013.06.186
M3 - Journal article
C2 - 23886548
SN - 1388-2457
VL - 125
SP - 352
EP - 362
JO - Clinical Neurophysiology
JF - Clinical Neurophysiology
IS - 2
ER -