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Altered brain function and structure in carpal tunnel syndrome: a systematic review and meta-analysis of structural and functional brain imaging

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Abstract

This systematic review with a meta-analysis aimed to identify the altered brain structure and function in carpal tunnel syndrome (CTS) by summarizing the literature about magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), and magnetoencephalography (MEG) outcomes compared to healthy controls (HC). CTS is the most common nerve entrapment in the arm associated with altered peripheral and central nociceptive system. PRISMA guidelines were used to report the outcomes. Six databases were searched for relevant literature (Web of Science, Scopus, PubMed, Sage, EBSCO host, and Cochrane). Eligible studies comparing MRI, fMRI, and MEG findings in people with CTS (present for at least 2 months) and HC through the following parameters: (1) interdigit cortical separation distance, (2) white and grey matter changes, (3) peak latency of M20 wave and recovery function of N20 from the somatosensory cortex (SI), and (4) surface area of activated digit cortical representation. The results from different studies were pooled and a meta-analysis was done. From 17 included, there was a significant reduction of interdigit cortical separation distance of index-middle and index-little fingers in the CTS (SMD = − 0.869, 95% CI (− 1.325, − 0.413), p-value = 0.000) and (SMD = − 0.79, 95% CI (− 1.217, − 0.364), p-value = 0.000), respectively. Middle-little fingers interdigit separation showed no difference (SMD = − 0.2, 95% CI (− 0.903, 1.309), p-value = 0.718). There is evidence supporting the altered brain structure and function in CTS as evidenced by reduction of interdigit cortical separation distance, and excessive blurring and disinhibition of SI, with low resting state functional connectivity. Thus, centrally directed therapeutic approaches might complement peripheral treatments.

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Data availability

The data will be available upon request from the corresponding author.

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Funding

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Authors and Affiliations

  1. Department of Physical Therapy for Musculoskeletal Disorders and its Surgery, Faculty of Physical Therapy, Cairo University, Giza, Egypt

    Mohamed Gomaa Sobeeh

  2. Department of Physical Therapy for Orthopedics and Orthopedic Surgery, Faculty of Physical Therapy, Sinai University, Ismailia, Egypt

    Mohamed Gomaa Sobeeh

  3. Faculty of Medicine, University of Algiers, Algiers, Algeria

    Amira Benmelouka

  4. Al-Azhar Faculty of Medicine, Cairo, Egypt

    Eslam Metwally

  5. Faculty of Medicine, Alexandria University, Alexandria, Egypt

    Mohammed Jawad Abuhassira, Sara Amr Nasr & Mohamed Fahmy Doheim

  6. Public Health Department, New Mexico State University, New Mexico, USA

    Ahmed Mohammed Abdeljalil

  7. Faculty of Medicine, Beni Suef University, Beni Suef, Egypt

    Ghidaa Osama El-Helw

Authors
  1. Mohamed Gomaa Sobeeh
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  2. Amira Benmelouka
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  4. Mohammed Jawad Abuhassira
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  5. Ahmed Mohammed Abdeljalil
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  8. Mohamed Fahmy Doheim
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all authors participated in writing of the manuscript, assessing risk of bias, selecting the included articles, and revising the extracted data.

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Correspondence to Mohamed Gomaa Sobeeh.

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Sobeeh, M.G., Benmelouka, A., Metwally, E. et al. Altered brain function and structure in carpal tunnel syndrome: a systematic review and meta-analysis of structural and functional brain imaging. Brain Struct Funct 229, 257–272 (2024). https://doi.org/10.1007/s00429-023-02737-5

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