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01-08-2014 | Original Article

Characterization of the motor units of the external anal sphincter in pregnant women with multichannel surface EMG

Authors: Corrado Cescon, Eleonora Ester Raimondi, Vita Začesta, Kristina Drusany-Starič, Konstantinos Martsidis, R. Merletti

Published in: International Urogynecology Journal | Issue 8/2014

Abstract

Introduction and hypothesis

Locating the innervation zones (IZs) of the external anal sphincter (EAS) is helpful to obstetricians to identify areas particularly vulnerable to episiotomy in pregnant women. The aim was to investigate the motor unit (MU) properties of the EAS during voluntary contractions.

Methods

Electromyographic signals were detected, from 478 pregnant women, by means of an intra-anal cylindrical probe carrying a circumferential array of 16 electrodes. The signals were decomposed into the constituent MU action potential trains and 5,947 templates were extracted and analyzed in order to identify the IZ position.

Results

MUs innervated at one end are concentrated in the dorsal portion of the sphincter, while MUs innervated in the middle are distributed symmetrically in the left and right portions of the EAS. The angular propagation velocity was estimated for each MU resulting in 260 ± 45 rad/s, corresponding to 1.8 m/s on the probe surface and to about 4 m/s at a radial depth of 10 mm from the probe surface.

Conclusions

A novel method for identification and classification of MUs of the EAS is proposed and applied to a large-scale study. It is possible to distinguish MUs of the EAS in a minimally invasive way and identify their IZs. This information should be used to plan episiotomies and minimize risks of EAS denervation.

Sultan AH, Kamm MA, Hudson CN, Thomas JM, Bartram CI (1993) Anal-sphincter disruption during vaginal delivery. N Engl J Med 329(26):1905–1911PubMedCrossRef

Sartore A, De Seta F, Maso G, Pregazzi R, Grimaldi E, Guaschino S (2004) The effects of mediolateral episiotomy on pelvic floor function after vaginal delivery. Obstet Gynecol 103(4):669–673PubMedCrossRef

Borello-France D, Burgio KL, Richter HE, Zyczynski H, Fitzgerald MP, Whitehead W, Fine P, Nygaard I, Handa VL, Visco AG, Weber AM, Brown MB, Pelvic Floor Disorders Network (2006) Fecal and urinary incontinence in primiparous women. Obstet Gynecol 108(4):863–872PubMedCrossRef

Fenner DE, Genberg B, Brahma P, Marek L, DeLancey JO (2003) Fecal and urinary incontinence after vaginal delivery with anal sphincter disruption in an obstetrics unit in the United States. Am J Obstet Gynecol 189(6):1543–1549, discussion 1549–1550PubMedCrossRef

Podnar S, Lukanovič A, Vodusek DB (2000) Anal sphincter electromyography after vaginal delivery: neuropathic insufficiency or normal wear and tear? Neurourol Urodyn 19(3):249–257PubMedCrossRef

Gregory WT, Lou JS, Simmons K, Clark AL (2008) Quantitative anal sphincter electromyography in primiparous women with anal incontinence. Am J Obstet Gynecol 198(5):550–556PubMedCentralPubMedCrossRef

Prutchi D (1995) A high-resolution large array (HRLA) surface EMG system. Med Eng Phys 17:442–454PubMedCrossRef

Lapatki BG, Oostenveld R, Van Dijk JP, Jonas IE, Zwarts MJ, Stegeman DF (2006) Topographical characteristics of motor units of the lower facial musculature revealed by means of high-density surface EMG. J Neurophysiol 95:342–354PubMedCrossRef

Holobar A, Farina D, Gazzoni M, Merletti R, Zazula D (2009) Estimating motor unit discharge patterns from high-density surface electromyogram. Clin Neurophysiol 120:551–562PubMedCrossRef

10.

Merletti R, Botter A, Cescon C, Minetto MA, Vieira TMM (2010) Advances in surface EMG: recent progress in clinical research applications. Crit Rev Biomed Eng 38(4):347–379PubMedCrossRef

11.

Ullah K, Afsharipour B, Cescon C, Merletti R (2014) Motor unit innervation zones of external anal sphincter from multichannel surface EMG using 2D correlation. Proc. of the 20th Int. Congress of ISEK, Rome 2014

12.

Enck P, Franz H, Azpiroz F, Fernandez-Fraga X, Hinninghofen H, Kaske-Bretag K, Bottin A, Martina S, Merletti R (2004) Innervation zones of the external anal sphincter in healthy male and female subjects. Preliminary results. Digestion 69:123–130PubMedCrossRef

13.

Cescon C, Bottin A, Azpiroz F, Merletti R (2008) Detection of individual motor units of the puborectalis muscle by non-invasive EMG electrode arrays. J Electromyogr Kinesiol 18(3):382–389PubMedCrossRef

14.

Merletti R, Bottin A, Cescon C, Farina D, Mesin L, Gazzoni M, Martina S, Pozzo M, Rainoldi A, Enck P (2004) Multichannel surface EMG for the non-invasive assessment of the anal sphincter muscle. Digestion 69:112–122PubMedCrossRef

15.

Enck P, Franz H, Davico E, Mastrangelo F, Mesin L, Merletti R (2010) Repeatability of innervation zone identification in the external anal sphincter muscle. Neurourol Urodyn 29:449–457PubMed

16.

Holobar A, Zazula D (2007) Gradient convolution kernel compensation applied to surface electromyograms. In: Davies ME, James CJ, Abdallah SA, Plumbley MD (eds) Indipendent component analysis and signal separation. Lecture notes in Computer Science, Vol. 4666. Springer Verlag, Heidelberg, pp 617–624

17.

Holobar A, Enck P, Hinninghofer H, Merletti R (2008) Decomposition of surface EMG from external anal sphincter. XVII Congress of the International Society of Electrophysiology and Kinesiology, Niagara Falls

18.

Cescon C (2006) Automatic location of muscle innervation zones from multi-channel surface EMG signals. Proceedings of the IEEE International Workshop on Medical Measurement and Applications (MeMeA2006), Benevento

Title: Characterization of the motor units of the external anal sphincter in pregnant women with multichannel surface EMG
Authors: Corrado Cescon
Eleonora Ester Raimondi
Vita Začesta
Kristina Drusany-Starič
Konstantinos Martsidis
R. Merletti
Publication date: 01-08-2014
Publisher: Springer London
Published in: International Urogynecology Journal / Issue 8/2014
Print ISSN: 0937-3462
Electronic ISSN: 1433-3023
DOI: https://doi.org/10.1007/s00192-014-2356-3

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Characterization of the motor units of the external anal sphincter in pregnant women with multichannel surface EMG

Abstract

Introduction and hypothesis

Methods

Results

Conclusions

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Introduction and hypothesis

Methods

Results

Conclusions

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