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Reduced somatosensory evoked potentials and paired-pulse inhibition in the primary somatosensory cortex of athletes with chronic pain

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Koya Yamashiro at Niigata University of Health and Welfare
Koya Yamashiro
Kanako Shiiya
Kanako Shiiya
Kanako Shiiya
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Koyuki Ikarashi at Niigata University of Health and Welfare
Koyuki Ikarashi
Sayaka Anazawa
Sayaka Anazawa
Sayaka Anazawa
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Abstract and Figures

Purpose Chronic pain impedes athletic training and performance. However, it is challenging to identify the precise causes of chronic pain for effective treatment. To examine possible neuroplastic changes in sensory transmission and cortical processing, we compared somatosensory evoked potentials (SEPs) and paired-pulse inhibition (PPI) in primary sensory cortex (S1) between athletes with chronic pain and control athletes. Methods Sixty-six intercollegiate athletes (39 males and 27 females) were recruited for this study, 45 control athletes and 21 reporting persistent pain for > 3 months. Sensory-evoked potentials were induced in S1 by constant-current square-wave pulses (0.2-ms duration) delivered to the right median nerve, while PPI was induced by paired stimulation at interstimulus intervals of 30 and 100 ms (PPI-30 and PPI-100 ms, respectively). All participants were randomly presented with total 1,500 (each 500 stimuli) single stimuli and stimulus pairs at 2 Hz. Results Both N20 amplitude and PPI-30 ms were significantly lower in athletes with chronic pain compared to control athletes, while P25 amplitude and PPI-100 ms did not differ significantly between groups. Conclusion Chronic pain in athletes is associated with substantially altered excitatory–inhibitory balance within the primary somatosensory cortex, possibly due to reduced thalamocortical excitatory transmission and suppressed cortical inhibitory transmission.
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Vol.:(0123456789)
1 3
European Journal of Applied Physiology (2023) 123:2537–2543
https://doi.org/10.1007/s00421-023-05224-1
ORIGINAL ARTICLE
Reduced somatosensory evoked potentials andpaired‑pulse
inhibition intheprimary somatosensory cortex ofathletes
withchronic pain
KoyaYamashiro1,2 · KanakoShiiya3· KoyukiIkarashi1,2· SayakaAnazawa3· TaikiMakibuchi1,3· YasuhiroBaba2·
TomomiFujimoto1,2· GentaOchi1,2· GoOmori2· DaisukeSato1,2
Received: 20 October 2022 / Accepted: 7 May 2023 / Published online: 17 June 2023
© The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023
Abstract
Purpose Chronic pain impedes athletic training and performance. However, it is challenging to identify the precise causes
of chronic pain for effective treatment. To examine possible neuroplastic changes in sensory transmission and cortical pro-
cessing, we compared somatosensory evoked potentials (SEPs) and paired-pulse inhibition (PPI) in primary sensory cortex
(S1) between athletes with chronic pain and control athletes.
Methods Sixty-six intercollegiate athletes (39 males and 27 females) were recruited for this study, 45 control athletes and
21 reporting persistent pain for > 3months. Sensory-evoked potentials were induced in S1 by constant-current square-wave
pulses (0.2-ms duration) delivered to the right median nerve, while PPI was induced by paired stimulation at interstimulus
intervals of 30 and 100ms (PPI-30 and PPI-100ms, respectively). All participants were randomly presented with total 1,500
(each 500 stimuli) single stimuli and stimulus pairs at 2Hz.
Results Both N20 amplitude and PPI-30ms were significantly lower in athletes with chronic pain compared to control
athletes, while P25 amplitude and PPI-100ms did not differ significantly between groups.
Conclusion Chronic pain in athletes is associated with substantially altered excitatory–inhibitory balance within the primary
somatosensory cortex, possibly due to reduced thalamocortical excitatory transmission and suppressed cortical inhibitory
transmission.
Keywords Primary somatosensory cortex (S1)· N20· Paired-pulse inhibition (PPI)· Disinhibition
Introduction
Chronic primary pain was previously defined as pain affect-
ing one or more anatomical regions that persisted or recurred
for over three months (Treede etal. 2019). In athletes, pain
can also occur independently of injury or persist after an
injury has healed as chronic pain (Tesarz etal. 2013; Small
2002). Indeed, chronic pain is recognized as a ubiquitous
problem among athletes and a challenge to treat and manage
(Hainline etal. 2017a, 2017b). Athletes may be afflicted by
many different types of chronic pain, including low back
pain (Coulombe etal. 2017), groin pain (Harmon 2007), and
lower leg pain (Edwards etal. 2005). In addition to nocicep-
tive and neuropathic pain caused by actual nerve damage,
athletes may develop nociplastic pain (Cohen etal. 2021),
a distinct neurophysiological construct involving increased
responsiveness of nociceptive neurons in the central nerv-
ous system to normal or subthreshold afferent input not
Communicated by Toshio Moritani.
Koya Yamashiro and Kanako Shiiya are equally contributed to this
study.
* Koya Yamashiro
yamashiro@nuhw.ac.jp
1 Institute forHuman Movement andMedical Sciences,
Niigata University ofHealth andWelfare, 1398
Shimami-cho, Kita-Ku, Niigata950-3198, Japan
2 Department ofHealth andSports, Niigata University
ofHealth andWelfare, 1398 Shimami-cho, Kita-Ku,
Niigata950-3198, Japan
3 Field ofHealth andSports, Graduate School ofNiigata,
University ofHealth andWelfare, 1398 Shimami-cho,
Kita-Ku, Niigata950-3198, Japan
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
ResearchGate has not been able to resolve any citations for this publication.
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