Examination of the descending pathway to the external anal sphincter and pelvic floor muscles by transcranial cortical stimulation

We investigated the effects of lumbosacral and pudendal nerve stimulation on the corticofugal pathways to the human external anal sphincter. In 11 healthy subjects, anal sphincter electromyographic responses, evoked to transcranial magnetic stimulation of the motor cortex, were recorded 5–500 ms after lumbosacral root or pudendal nerve stimulation. Lumbosacral and pudendal nerve stimulation alone evoked responses with amplitudes of 293 ± 73 and 401 ± 153 μV and latencies of 3.2 ± 0.2 and 2.2 ± 0.2 ms, respectively. Cortical stimulation also evoked responses with amplitudes of 351 ± 104 μV and latencies of 20.9 ± 1.1 ms. When lumbosacral or pudendal nerve stimulation preceded cortical stimulation, the cortically evoked responses were facilitated ( P < 0.01), with the effect appearing greatest at 5–20 ms after both lumbosacral and pudendal excitation and at 50–100 ms after lumbosacral excitation alone. Our results demonstrate that cortical pathways to the external anal sphincter are facilitated by prior lumbosacral and pudendal nerve stimulation, indicating that sensorimotor interactions are important in the central neural control of sphincter function.

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Various significant connections of the male pelvic floor muscles with special reference to the anal and urethral sphincter muscles

Anatomical Science International ◽

10.1007/s12565-019-00521-2 ◽

2019 ◽

Vol 95 (3) ◽

pp. 305-312 ◽

Cited By ~ 1

Author(s):

Janyaruk Suriyut ◽

Satoru Muro ◽

Phichaya Baramee ◽

Masayo Harada ◽

Keiichi Akita

Keyword(s):

Pelvic Floor ◽

Anal Sphincter ◽

External Anal Sphincter ◽

Complex Structure ◽

Levator Ani ◽

Levator Ani Muscle ◽

Urethral Sphincter ◽

External Urethral Sphincter ◽

Lateral Aspect ◽

Close Relationship

AbstractThe male pelvic floor is a complex structure formed by several muscles. The levator ani muscle and the perineal muscles are important components of the pelvic floor. The perineal muscles comprise the external anal sphincter, bulbospongiosus, superficial transverse perineal muscles, and ischiocavernosus. Although the connections of the muscles of the pelvic floor have been reported recently, the anatomical details of each muscle remain unclear. In this study, we examined the male pelvic floor to clarify the connection between the muscles related to function. Fifteen male pelvises were used for microscopic dissection, and three male pelvises were used for histological examination. On the lateral aspect, the perineal muscles were connected to each other. Bundles of the levator ani muscle extended to connect to the perineal muscles. In addition, the extended muscle bundle from the levator ani muscle and the perineal muscles surround the external urethral sphincter. On the medial aspect, the levator ani muscle and the external anal sphincter form the anterior and posterior muscular slings of the anal canal. The connection between the perineal muscles and levator ani muscle indicates a possible close relationship between the functions of the urethra and anus.

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FUNCTIONAL STATE OF THE PELVIC FLOOR MUSCLES IN PATIENTS WITH THE PELVIC PROLAPSE

Koloproktologia ◽

10.33878/2073-7556-2017-0-2-55-61 ◽

2017 ◽

pp. 55-61

Author(s):

O. Yu. Fomenko ◽

Yu. A. Shelygin ◽

G. V. Poryadin ◽

A. Yu. Titov ◽

A. A. Ponomarenko ◽

...

Keyword(s):

Physical Examination ◽

Pelvic Floor ◽

Anal Sphincter ◽

Functional State ◽

Diagnostic Algorithm ◽

Pelvic Floor Muscles ◽

Functional Study ◽

Rectal Intussusception ◽

Study Results ◽

Obstructive Defecation

The article analyzes the functional state (evacuation functions, continence) and innervation of the pelvic floor muscles in patients with rectocele and combination rectocele with internal rectal intussusception, with complaints of obstructive defecation. AIM. The study of the functional state of the pelvic floor muscles in patients with obstructive defecation syndrome (ODS). MATERIALS AND METHODS. The study included 224 women with complaints of obstructive defecation, without pelvic floor surgery. On physical examination, all patients were detected signs of rectocele. The average age - 49,9±15,0 years. 52 (23,2%) patients had complaints to the fecal incontinence of various components. Diagnostic algorithm: physical examination defecography, rectal functional study (high resolution manometry (HRAM), evacuation test, comprehensive sphincterometry, pudendal nerve study). RESULTS. Frequency of functional disorders of defecation (FDD) according to objective methods of study among patients with ODS is high and amounts to 64.7%. In this case, there are no differences in the frequency FDD in patients with a combination of rectocele and internal intussusception compared to patients with only rectocele. There were no correlation between the frequency of anal sphincter failure and FDD. We identified some patients with subclinical incontinence, without complaints but with reduced manometric values and anal sphincter contractility. We have proved the absence of correlation between the presence or absence of pelvic floor muscle innervations violations in the form of neuropathy n. pudendus and the presence or absence of FDD. CONCLUSION. FDD can cause unsatisfactory results of surgical treatment of patients with ODS, even after the restoration of the anatomic relationships due to complaints of evacuation violation. ODS diagnostic algorithm should include not only an assessment of evacuationfunction (HRAM and evacuation test), but also sphincterometry, to assess the content function.

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Pelvic muscle electromyography of levator ani and external anal sphincter in nulliparous women and women with pelvic floor dysfunction

American Journal of Obstetrics and Gynecology ◽

10.1067/mob.2000.111073 ◽

2000 ◽

Vol 183 (6) ◽

pp. 1390-1401 ◽

Cited By ~ 53

Author(s):

Alison C. Weidner ◽

Matthew D. Barber ◽

Anthony G. Visco ◽

Richard C. Bump ◽

Donald B. Sanders

Keyword(s):

Pelvic Floor ◽

Anal Sphincter ◽

External Anal Sphincter ◽

Pelvic Floor Dysfunction ◽

Levator Ani ◽

Nulliparous Women

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Vesico-anal influences in healthy intact humans: Quantificated by responses in the external anal sphincter following transcranial cortical stimulation

Neurourology and Urodynamics ◽

10.1002/nau.1930090304 ◽

1990 ◽

Vol 9 (3) ◽

pp. 257-268

Author(s):

Michael V. Hansen ◽

Helen Holmgren ◽

Anders Sp∠berg ◽

Andrej Warycha

Keyword(s):

Anal Sphincter ◽

External Anal Sphincter ◽

Cortical Stimulation

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Quantification of motor pathways to the pelvic floor in humans

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1991.260.5.g720 ◽

1991 ◽

Vol 260 (5) ◽

pp. G720-G723 ◽

Cited By ~ 6

Author(s):

J. Herdmann ◽

K. Bielefeldt ◽

P. Enck

Keyword(s):

Pelvic Floor ◽

Evoked Potentials ◽

Anal Sphincter ◽

External Anal Sphincter ◽

Motor Evoked Potentials ◽

Motor Innervation ◽

Anterior Tibial Muscle ◽

Motor Pathways ◽

Anterior Tibial ◽

Stimulation Of

The motor innervation of the pelvic floor plays a major role in defecation disorders such as fecal incontinence. It consists of central motor pathways and peripheral nerve fibers. Transcranial magnetoelectric stimulation of the brain and magnetoelectric stimulation of the lumbosacral motor roots were performed in 10 healthy volunteers. Motor evoked potentials were recorded from the external anal sphincter. This procedure allowed differentiation between a predominantly central and a solely peripheral component of the motor innervation of the external and sphincter. To compare these recordings with well-established data, motor evoked potentials were also recorded from the anterior tibial muscle. The central motor conduction time was 20.9 +/- 2.4 ms to the external anal sphincter and 14.8 +/- 2.3 ms to the anterior tibial muscles. Central motor conduction velocities were 40.7 +/- 5.2 and 55.5 +/- 7.6 m/s, respectively. This showed that conduction in the central fibers to the external anal sphincter was significantly slower than in those to the anterior tibial muscle. We conclude 1) that magnetoelectric stimulation allows differentiation between central and peripheral portions of the motor innervation of the pelvic floor, and 2) that central motor pathways innervating the pelvic floor differ significantly in their physiological properties from those innervating limb muscles.

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