Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2018 Sep 24;14(1):290.
doi: 10.1186/s12917-018-1620-z.

Magnetic motor evoked potentials of cervical muscles in horses

Joke Rijckaert  1 , Bart Pardon  2 , Luc Van Ham  3 , Philip Joosten  4 , Gunther van Loon  2 , Piet Deprez  2
Affiliations

Magnetic motor evoked potentials of cervical muscles in horses

Joke Rijckaert et al. BMC Vet Res. .

Abstract

Background: When surgical treatment of cervical vertebral malformation is considered, precise localization of compression sites is essential, but remains challenging. Magnetic motor evoked potentials (mMEP) from paravertebral muscles are useful in localizing spinal cord lesions, but no information about cervical muscle mMEP in horses is available yet. Therefore, the aim of this study was to determine the possibility, normal values, inter- and intra-observer agreement and factors that have an effect on cervical mMEP in healthy horses.

Methods: Transcranial magnetic stimulation was performed on 50 normal horses and 4 (2 left, 2 right) muscle responses were recorded at the middle of each cervical vertebra (C1-C7) and additionally just caudal to C7 to evaluate cervical nerves (Cn) Cn1 to Cn8. Latency time and amplitude of the recorded mMEP were defined by both an experienced and an unexperienced operator.

Results: Latency increased gradually from 14.2 ± 1.38 ms for Cn3 to 17.7 ± 1.36 ms for Cn8, was significantly influenced by cervical nerve (P < 0.01), gender (P = 0.02) and height (P = 0.03) and had a good intra-observer agreement. The smallest mean amplitude (4.35 ± 2.37 mV) was found at Cn2, the largest (5.99 ± 2.53 mV) at Cn3. Amplitude was only significantly influenced by cervical nerve (P < 0.01) and had a low intra-observer agreement. No significant effect of observer on latency (P = 0.88) or amplitude (P = 0.99) measurements was found.

Conclusion: mMEP of cervical muscles in normal horses are easy to collect and to evaluate with limited intra- and inter-observer variation concerning amplitude and should be investigated in future studies in ataxic horses to evaluate its clinical value.

Keywords: EMG; Neurologic test; Spinal ataxia; Surgery; Transcranial magnetic stimulation.

PubMed Disclaimer

Conflict of interest statement

Ethics approval and consent to participate

The experimental protocol was approved by the Ethical Committee of the Faculty of Veterinary Medicine at Ghent University (case number EC 2016/59). Written informed consent to use the animals in the present study was obtained from the owner of the animals.

Consent for publication

Not Applicable.

Competing interests

The authors declare that they have no competing interests.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Figures

Fig. 1
Fig. 1
Boxplots for all latency values per cervical nerve (8 times n = 200). Significant differences (P < 0.01) from group 3, the group with the lowest latency values, are indicated by *, outliers are indicated by a circle
Fig. 2
Fig. 2
Boxplots for all amplitude values per cervical nerve (8 times n = 200). Analogous to latency, significant differences (P < 0.01) from group 3 are indicated by *, outliers are indicated by a circle
Fig. 3
Fig. 3
Interaction between gender (0 = male and 1 = female) and cervical nerve on latency. Significant differences (P < 0.05) are demonstrated by *
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Tani T, Yamamoto H, Kimura J. Cervical spondylotic myelopathy in elderly people: a high incidence of conduction block at C3-4 or C4-5. J Neurol Neurosur Ps. 1999;66(4):456–464. doi: 10.1136/jnnp.66.4.456. - DOI - PMC - PubMed
    1. Nardone R, Holler Y, Thomschewski A, Holler P, Bergmann J, Golaszewski S, et al. Central motor conduction studies in patients with spinal cord disorders: a review. Spinal Cord. 2014;52(6):420–427. doi: 10.1038/sc.2014.48. - DOI - PubMed
    1. Barker AT, Jalinous R, Freeston IL. Non-invasive magnetic stimulation of human motor cortex. Lancet. 1985;1(8437):1106–1107. doi: 10.1016/S0140-6736(85)92413-4. - DOI - PubMed
    1. Boden SD, McCowin PR, Davis DO, Dina TS, Mark AS, Wiesel S. Abnormal magnetic-resonance scans of the cervical spine in asymptomatic subjects. A prospective investigation. J Bone Joint Surg Am. 1990;72(8):1178–1184. doi: 10.2106/00004623-199072080-00008. - DOI - PubMed
    1. Levine JM, Adam E, MacKay RJ, Walker MA, Frederick JD, Cohen ND. Confirmed and presumptive cervical vertebral compressive myelopathy in older horses: a retrospective study (1992-2004) J Vet Intern Med. 2007;21(4):812–819. - PubMed