TY - JOUR
T1 - Experimental muscle hyperalgesia modulates sensorimotor cortical excitability, which is partially altered by unaccustomed exercise
AU - De Martino, Enrico
AU - Zandalasini, Matteo
AU - Schabrun, Siobhan
AU - Petrini, Laura
AU - Graven-Nielsen, Thomas
PY - 2018
Y1 - 2018
N2 - Impaired corticomotor function is reported in patients with lateral epicondylalgia, but the causal link to pain or musculotendinous overloading is unclear. In this study, sensorimotor cortical changes were investigated using a model of persistent pain combined with an overloading condition. In 24 healthy subjects, the effect of nerve growth factor (NGF) induced pain, combined with delayed onset muscle soreness (DOMS), was examined on pain perception, pressure pain sensitivity, maximal force, and sensorimotor cortical excitability. Two groups (NGF alone, NGF+DOMS) received injections of NGF into the extensor carpi radialis brevis (ECRB) muscle at Day-0, Day-2, and Day-4. At Day-4, the NGF+DOMS group undertook wrist eccentric exercise to induce DOMS in the ECRB muscle. Muscle soreness scores, pressure pain thresholds (PPT) over the ECRB muscle, maximal grip force, transcranial magnetic stimulation (TMS) mapping of the cortical ECRB muscle representation and somatosensory evoked potentials (SEPs) from radial nerve stimulation were recorded at Day-0, Day-4 and Day-6. Compared with Day-0, Day-4 showed in both groups: 1) Increased muscle soreness (P<0.01); 2) Reduced PPTs (P<0.01); 3) Increased motor map volume (P<0.01); 4) Decreased frontal N30 SEP. At Day-6, compared with Day-4, only the DOMS+NGF group showed: 1) Increased muscle soreness score (P<0.01); 2) Decreased grip force (P<0.01); 3) Decreased motor map volume (P<0.05). The NGF group did not show any difference on the remaining outcomes from Day-4 to Day-6. These data suggest that sustained muscle pain modulates sensorimotor cortical excitability and that exercise-induced DOMS alters pain-related corticomotor adaptation.
AB - Impaired corticomotor function is reported in patients with lateral epicondylalgia, but the causal link to pain or musculotendinous overloading is unclear. In this study, sensorimotor cortical changes were investigated using a model of persistent pain combined with an overloading condition. In 24 healthy subjects, the effect of nerve growth factor (NGF) induced pain, combined with delayed onset muscle soreness (DOMS), was examined on pain perception, pressure pain sensitivity, maximal force, and sensorimotor cortical excitability. Two groups (NGF alone, NGF+DOMS) received injections of NGF into the extensor carpi radialis brevis (ECRB) muscle at Day-0, Day-2, and Day-4. At Day-4, the NGF+DOMS group undertook wrist eccentric exercise to induce DOMS in the ECRB muscle. Muscle soreness scores, pressure pain thresholds (PPT) over the ECRB muscle, maximal grip force, transcranial magnetic stimulation (TMS) mapping of the cortical ECRB muscle representation and somatosensory evoked potentials (SEPs) from radial nerve stimulation were recorded at Day-0, Day-4 and Day-6. Compared with Day-0, Day-4 showed in both groups: 1) Increased muscle soreness (P<0.01); 2) Reduced PPTs (P<0.01); 3) Increased motor map volume (P<0.01); 4) Decreased frontal N30 SEP. At Day-6, compared with Day-4, only the DOMS+NGF group showed: 1) Increased muscle soreness score (P<0.01); 2) Decreased grip force (P<0.01); 3) Decreased motor map volume (P<0.05). The NGF group did not show any difference on the remaining outcomes from Day-4 to Day-6. These data suggest that sustained muscle pain modulates sensorimotor cortical excitability and that exercise-induced DOMS alters pain-related corticomotor adaptation.
KW - exercise
KW - hyperalgesia
KW - muscles
KW - neuroplasticity
KW - pain
KW - sensorimotor cortex
UR - http://handle.westernsydney.edu.au:8081/1959.7/uws:47795
U2 - 10.1097/j.pain.0000000000001351
DO - 10.1097/j.pain.0000000000001351
M3 - Article
SN - 1872-6623
SN - 0304-3959
VL - 159
SP - 2493
EP - 2502
JO - Pain
JF - Pain
IS - 12
ER -