State of the art review: Intravaginal probes for recording electromyography from the pelvic floor muscles

Vaginal Sensors

The development and market emergence of vaginal sensors have begun to demonstrate their impact on women's healthcare. Until recently, in limited cases, these sensors have exhibited their capabilities in diagnosing and monitoring disorders of the vaginal tract during different stages of women's lives. This Perspective is a compilation of what has been accomplished so far in the landscape of vaginal sensors. The text explores the diverse types of vaginal sensor technologies, their applications, and their potential impact on women's healthcare. The review introduces the anatomy of the vagina and cervix and categorizes vaginal sensors that have been developed, highlighting the technologies and potential applications. The paper covers biomarkers of the vaginal tract and discusses their importance in maintaining the overall characteristics of the vaginal system. The text also explores the clinical implications of vaginal sensors in pregnancy monitoring, disease detection, and sexual health management. In the final step, the manuscript provides future perspectives and possibilities that can be incorporated in the emerging field of vaginal sensors.

Technologies for Evaluation of Pelvic Floor Functionality: A Systematic Review

Pelvic floor dysfunction is a common problem in women and has a negative impact on their quality of life. The aim of this review was to provide a general overview of the current state of technology used to assess pelvic floor functionality. It also provides literature research of the physiological and anatomical factors that correlate with pelvic floor health. This systematic review was conducted according to the PRISMA guidelines. The PubMed, ScienceDirect, Cochrane Library, and IEEE databases were searched for publications on sensor technology for the assessment of pelvic floor functionality. Anatomical and physiological parameters were identified through a manual search. In the systematic review, 114 publications were included. Twelve different sensor technologies were identified. Information on the obtained parameters, sensor position, test activities, and subject characteristics was prepared in tabular form from each publication. A total of 16 anatomical and physiological parameters influencing pelvic floor health were identified in 17 published studies and ranked for their statistical significance. Taken together, this review could serve as a basis for the development of novel sensors which could allow for quantifiable prevention and diagnosis, as well as particularized documentation of rehabilitation processes related to pelvic floor dysfunctions.

Consensus for experimental design in electromyography (CEDE) project: Checklist for reporting and critically appraising studies using EMG (CEDE-Check)

The diversity in electromyography (EMG) techniques and their reporting present significant challenges across multiple disciplines in research and clinical practice, where EMG is commonly used. To address these challenges and augment the reproducibility and interpretation of studies using EMG, the Consensus for Experimental Design in Electromyography (CEDE) project has developed a checklist (CEDE-Check) to assist researchers to thoroughly report their EMG methodologies. Development involved a multi-stage Delphi process with seventeen EMG experts from various disciplines. After two rounds, consensus was achieved. The final CEDE-Check consists of forty items that address four critical areas that demand precise reporting when EMG is employed: the task investigated, electrode placement, recording electrode characteristics, and acquisition and pre-processing of EMG signals. This checklist aims to guide researchers to accurately report and critically appraise EMG studies, thereby promoting a standardised critical evaluation, and greater scientific rigor in research that uses EMG signals. This approach not only aims to facilitate interpretation of study results and comparisons between studies, but it is also expected to contribute to advancing research quality and facilitate clinical and other practical applications of knowledge generated through the use of EMG.

Techniques for Registration of Myoelectric Activity of Women's Pelvic Floor Muscles: A Scoping Review

INTRODUCTION AND HYPOTHESIS

Surface electromyography is commonly applied to measure the electrophysiological activity of the neuromuscular system. However, there is no consensus regarding the best protocol to assess pelvic floor muscles.

METHODS

A scoping literature review was carried out in six databases, using MeSH descriptors. It included studies with electromyographic assessment in adult women presenting or not with pelvic floor dysfunction. The results were presented in categories to contribute to the development of a protocol considering the most used parameters for non-invasive assessment of myoelectric activity of pelvic floor muscles.

RESULTS

A total of 1,074 articles were identified, and 146 studies were selected for analysis. The intravaginal probe was used in 80.8% of the studies, the bipolar sensor with metallic plates placed on both sides of the vagina was the most frequent (71.3%), with a reference electrode positioned on the anterior superior iliac spine (33.5%). The supine position with hip and knee flexed (45.2%) was the most frequent position used. Of the studies, 44.5% normalized the data by maximum voluntary contraction (MVC) whereas 44.5% performed an average of 3 MVCs.

CONCLUSIONS

The most frequently used protocol for the pelvic floor is the bipolar intracavitary probe with metal plates positioned at 3-9 o'clock and introduced distally to the vaginal introitus with the volunteer in the supine position and the hip and knee flexed with the reference placed on the anterior-superior iliac spine.

Differences in pelvic floor muscle morphology and function between female runners with and without running-induced stress urinary incontinence

OBJECTIVE

To investigate the differences in pelvic floor muscle (PFM) morphology and function between female runners with and without running-induced stress urinary incontinence (RI-SUI).

DESIGN

This was a cross-sectional, observational study.

METHODS

Experienced female runners were recruited into two groups: runners who regularly experience RI-SUI (n = 19) and runners who do not (n = 20). Active and passive pelvic floor muscle (PFM) properties were assessed using intravaginal dynamometry during maximal voluntary contractions (MVC) and during passive tissue elongation. The morphology of the urethra and PFMs was assessed using 2D and 3D transperineal ultrasound imaging. Independent t tests or Mann-Whitney U were used as appropriate to test group differences on all study outcomes, and Cohen's d effect sizes were calculated.

RESULTS

The rate of force development during the MVC was significantly higher in participants reporting RI-SUI (p ≤ 0.05) and conversely, significantly lower during passive elongation of the PFMs (p ≤ 0.05) compared to runners with no history of leakage. Concurrently, the extent of bladder neck elevation between rest and maximum voluntary activation was significantly higher among those with RI-SUI compared to those without. Although not significant, small to moderate effect sizes were observed for other outcomes-active force outcomes measured during MVC tended to be higher in runners with RI-SUI, while passive force outcomes measured during passive tissue elongation tended to be lower. The cross-sectional area of the urethral wall and the area of the levator hiatus tended to be larger in runners with RI-SUI compared to those without.

CONCLUSION

Runners who experience RI-SUI demonstrate better PFM contractile function but lower passive support when compared to their continent counterparts.

Intrinsic factors contributing to elevated intra-abdominal pressure

Pelvic floor disorders affect 24% of US women, and elevated intra-abdominal pressure may cause pelvic injury through musculoskeletal strain. Activity restrictions meant to reduce pelvic strain after traumatic events, such as childbirth, have shown little benefit to patients. Reported high variability in abdominal pressure suggests that technique plays a substantial role in pressure generation. Understanding these techniques could inform evidence-based recommendations for protective pelvic care. We hypothesized use of a motion-capture methodology could identify four major contributors to elevated pressure: gravity, acceleration, abdominal muscle contraction, and respiration. Twelve women completed nineteen activities while instrumented for whole body motion capture, abdominal pressure, hip acceleration, and respiration volume. Correlation and partial least squares regression were utilized to determine primary technique factors that increase abdominal pressure. The partial least squares model identified two principal components that explained 59.63% of relative intra-abdominal pressure variability. The first component was primarily loaded by hip acceleration and relative respiration volume, and the second component was primarily loaded by flexion moments of the abdomen and thorax. While reducing abdominal muscle use has been a primary strategy in protective pelvic floor care, the influence of hip acceleration and breathing patterns should be considered with similar importance in future work.

Current developments in surface electromyography

Background/aim

Surface electromyography (surface EMG) is a primary technique to detect the electrical activities of muscles through surface electrodes. In recent years, surface EMG applications have grown from conventional fields into new fields. However, there is a gap between the progress in the research of surface EMG and its clinical acceptance, characterized by the translational knowledge and skills in the widespread use of surface EMG among the clinician community. To reduce this gap, it is necessary to translate the updated surface EMG applications and technological advances into clinical research. Therefore, we aimed to present a perspective on recent developments in the application of surface EMG and signal processing methods.

Materials and methods

We conducted this scoping review following the Joanna Briggs Institute (JBI) method. We conducted a general search of PubMed and Web of Science to identify key search terms. Following the search, we uploaded selected articles into Rayyan and removed duplicates. After prescreening 133 titles and abstracts, we assessed 91 full texts according to the inclusion criteria.

Results

We concluded that surface EMG has made innovative technological progress and has research potential for routine clinical applications and a wide range of applications, such as neurophysiology, sports and art performances, biofeedback, physical therapy and rehabilitation, assessment of physical exercises, muscle strength, fatigue, posture and postural control, movement analysis, muscle coordination, motor synergies, modelling, and more. Novel methods have been applied for surface EMG signals in terms of time domain, frequency domain, time-frequency domain, statistical methods, and nonlinear methods.

Conclusion

Translating innovations in surface EMG and signal analysis methods into routine clinical applications can be a helpful tool with a growing and valuable role in muscle activation measurement in clinical practices. Thus, researchers must build many more interfaces that give opportunities for continuing education and research with more contemporary techniques and devices.

Multifunctional Evaluation Technology for Diagnosing Malfunctions of Regional Pelvic Floor Muscles Based on Stretchable Electrode Array Probe

The pelvic floor dysfunction (PFD) has become a serious public health problem. Accurate diagnosis of regional pelvic floor muscle (PFM) malfunctions is vitally important for the prevention and treatment of PFD. However, there is a lack of reliable diagnostic devices to evaluate and diagnose regional PFM abnormality. In this work, we developed a multifunctional evaluation technology (MET) based on a novel airbag-type stretchable electrode array probe (ASEA) for the diagnosis of malfunctions of regional PFM. The inflatable ASEA has specifically distributed 32 electrodes along the muscles, and is able to adapt to different human bodies for tight contact with the muscles. These allow synchronous collection of high-quality multi-channel surface electromyography (MC-sEMG) signals, and then are used to diagnose regional PFM malfunctions and evaluate inter-regional correlation. Clinical trial was conducted on 15 postpartum stress urinary incontinence (PSUI) patients and 15 matched asymptomatic women. Results showed that SUI patients responded slowly to the command and have symptoms of muscle strength degeneration. The results were consistent with the relevant clinical manifestations, and proved the reliability of MET for multifunctional PFM evaluation. Furthermore, the MET can diagnose malfunctions of regional PFM, which is inaccessible with existing technology. The results also showed that the dysfunction of PSUI patients is mainly located in iliococcygeus, pubococcygeus, and urethral sphincter regions, and there is a weak correlation between these specific regions and nearby regions. In conclusion, MET provides a point-of-care diagnostic method for abnormal function of regional PFM, which has a potential for the targeted point-to-point electrical stimulation treatment and PFD pathology research.

Functional Exercise Versus Specific Pelvic Floor Exercise: Observational Pilot Study in Female University Students

OBJECTIVES

To evaluate the electromyographic (EMG) activity of the pelvic floor musculature (PFM) that takes place when performing the functional movement screen (FMS) exercise, comparing it with the activation in the maximum voluntary contraction of PFM in the supine position (MVC-SP) and standing (MVC-ST).

MATERIAL AND METHODS

A descriptive, observational study conducted in two phases. In the first study phase, the baseline EMG activity of PFM was measured in the supine position and standing during MVC-SP and MVC-ST and during the execution of the seven exercises that make up the FMS. In the second phase of the study, the baseline EMG activity of PFM was measured in the supine position and standing during MVC-SP and MVC-ST and during the FMS exercise that produced the most EMG in the pilot phase: trunk stability push-up (PU). ANOVA, Friedman's and Pearson's tests were used.

RESULTS

All FMS exercises performed in the pilot phase showed a value below 100% maximum voluntary contraction (MVC) except PU, which presented an average value of 101.3 μv (SD = 54.5): 112% MVC (SD = 37.6). In the second phase of the study, it was observed that there were no significant differences (p = 0.087) between the three exercises performed: MVC-SP, MVC-ST and PU (39.2 μv (SD = 10.4), 37.5 μv (SD = 10.4) and 40.7 μv (SD = 10.2), respectively).

CONCLUSIONS

There is no evidence of the existence of significant differences in EMG activation in PFM among the three exercises analysed: MVC-SP, MVC-ST and PU. The results show better EMG values in the functional exercise of PU.

Is there a difference in pelvic floor muscle tone between women with and without pelvic pain? A systematic review and meta-analysis

BACKGROUND

Alterations in pelvic floor muscle (PFM) function have been observed in women with persistent noncancer pelvic pain (PNCPP) as compared with women without PNCPP; however, the literature presents conflicting findings regarding differences in PFM tone between women with and without PNCPP.

AIM

To systematically review the literature comparing PFM tone in women with and without PNCPP.

METHODS

MEDLINE, Embase, Emcare, CINAHL, PsycINFO, and Scopus were searched from inception to June 2021 for relevant studies. Studies were included that reported PFM tone data in women aged ≥18 years with and without PNCPP. The risk of bias was assessed with the National Heart, Lung, and Blood Institute Quality Assessment Tool. Standardized mean differences (SMDs) for PFM tone measures were calculated via random effects models.

OUTCOMES

Resting PFM tone parameters, including myoelectrical activity, resistance, morphometry, stiffness, flexibility, relaxation, and intravaginal pressure, measured by any clinical examination method or tool.

RESULTS

Twenty-one studies met the inclusion criteria. Seven PFM tone parameters were measured. Meta-analyses were conducted for myoelectrical activity, resistance, and anterior-posterior diameter of the levator hiatus. Myoelectrical activity and resistance were higher in women with PNCPP than in women without (SMD = 1.32 [95% CI, 0.36-2.29] and SMD = 2.05 [95% CI, 1.03-3.06], respectively). Women with PNCPP also had a smaller anterior-posterior diameter of the levator hiatus as compared with women without (SMD = -0.34 [95% CI, -0.51 to -0.16]). Meta-analyses were not performed for the remaining PFM tone parameters due to an insufficient number of studies; however, results of these studies suggested greater PFM stiffness and reduced PFM flexibility in women with PNCPP than in women without.

CLINICAL IMPLICATIONS

Available evidence suggests that women with PNCPP have increased PFM tone, which could be targeted by treatments.

STRENGTHS AND LIMITATIONS

A comprehensive search strategy was used with no restriction on language or date to review studies evaluating PFM tone parameters between women with and without PNCPP. However, meta-analyses were not undertaken for all parameters because few included studies measured the same PFM tone properties. There was variability in the methods used to assess PFM tone, all of which have some limitations.

CONCLUSION

Women with PNCPP have higher PFM tone than women without PNCPP; therefore, future research is required to understand the strength of the relationship between pelvic pain and PFM tone and to investigate the effect of treatment modalities to reduce PFM tone on pelvic pain in this population.

Evaluation of Pelvic Floor Muscles in Pregnancy and Postpartum With Non-Invasive Magnetomyography

Objective: To record and characterize features of levator ani muscles (LAM) activity in pregnancy and postpartum using non-invasive and novel Magnetomyography (MMG) technique with amplitude and spectral parameters. Methods: Nulliparous women with uncomplicated pregnancies participated in the MMG data collection during rest and voluntary LAM contractions (Kegels) with modulated intensity in third trimester and approximately 2 months postpartum (PP). Simultaneous surface electromyography was recorded to document the recruitment of accessory muscles. Moderate strength Kegel (MK) MMG trials were analyzed. Amplitude and spectral parameters including root-mean square (RMS) amplitude, power spectrum density (PSD) and normalized PSD (rPSD) in three frequency bands (low, middle, high) were computed on MK epochs. Statistical comparisons between pregnancy and postpartum were calculated. Results: MMG recordings were measured from 10 pregnant women. Results showed decreased RMS and power between third trimester and postpartum, trending towards significance. rPSD values in the low frequency band decreased significantly (p = 0.028) from third trimester to postpartum, while significant increase was observed in the middle frequency band (p = 0.018). Conclusions: This study shows that MMG as non-invasive tool has the ability to detect and characterize changes of LAM activity with amplitude and spectral parameters during pregnancy and postpartum.

Pelvic floor tissue damping during running using an intra-vaginal accelerometry approach

BACKGROUND

While cumulative loading of the pelvic floor during exercise appears to increase the risk of developing pelvic floor disorders, the pathophysiologic role of pelvic floor loading is poorly understood. The aim of this exploratory study was to present a method for evaluating vibrational frequency damping of the female pelvic floor and to investigate the potential utility of this approach in a preliminary evaluation.

METHODS

Female participants were instrumented with an intravaginal accelerometer and a hip-mounted accelerometer, then ran on a treadmill at 7 km/h and 10 km/h both before and after a 30-min self-selected pace. Displacement of the pelvic floor relative to the bony pelvis was calculated using double integration of the accelerometer data. Vibrational damping coefficients were calculated using a wavelet-based approach to determine the effect of continence status, parity, running speed and time on vibrational damping.

FINDINGS

Seventeen women (n = 10 reported regularly leaking urine while exercising, while n = 7 reported not leaking) completed the running protocol. No differences in vibrational damping were detected between continent and incontinent women when all frequency bands were evaluated together, however significant effects of parity, time, running speed and continence status were found within specific frequency bands. Parous women demonstrated less damping in the 25-40 Hz band compared to nulliparae, damping in the 13-16 Hz band was lower after the 30-min run, and incontinent women demonstrated lower damping in the 4.5-5.5 Hz band than continent women when running at 7 km/h.

INTERPRETATION

Intra-vaginal vibrational damping may be useful in detecting biomechanical mechanisms associated with pelvic floor disorders experienced by females during exercise.

A systematic review of diagnostic tests to detect pelvic floor myofascial pain

INTRODUCTION AND HYPOTHESIS

Myofascial pain arising from pelvic floor muscles occurs in women with vaginismus, interstitial cystitis and endometriosis but is often overlooked. The aim is to examine alternative diagnostic tests to detect pelvic floor myofascial pain compared with standardized vaginal palpation of pelvic floor muscles as the reference test.

METHODS

A systematic review was prospectively conducted (PROSPERO-CRD42020183092) according to PRISMA guidelines. Databases searched included Ovid Medline 1946-, Embase 1957-, Scopus 1960-, Cochrane Combined, Clinical trials, Google Scholar (top 200 articles), Web of Science, TRIP, BIOSIS, DARE, CINHAL, EmCare, PEDro, ProQuest and EBSCOhost up to July 2020. Articles were independently screened by two authors and assessed for bias using QUASDAS-2 tool.

RESULTS

A total of 26,778 articles were screened and 177 were selected for full text review, of which 5 were selected for final analysis. Five studies included 9694 participants of which 1628 had pelvic floor myofascial pain. Only one study reported data to calculate sensitivities and specificities of the index test, which utilized a score of > 40 on the Central Sensitization Inventory to detect women with pelvic floor myofascial pain and revealed a sensitivity of 34.8% and a specificity of 84.9% compared to the reference test.

CONCLUSIONS

This systematic review did not reveal any diagnostic test superior to the pre-defined reference test. There is a lack of consensus on the definition of pelvic floor myofascial pain and a lack of a validated diagnostic criteria which must be addressed to progress with meaningful research in this field.

Electromyographic analysis of maximal voluntary contraction of female pelvic floor muscles: Intrarater and interrater reliability study

AIMS

To investigate the intrarater and interrater reliability of the surface electromyography (sEMG) of female pelvic floor muscles (PFM) by visual determination of the onset-offset during maximal voluntary contraction (MVC).

METHODS

Intrarater and interrater reliability study. Three MVC, recorded for 5 s (s) each and separated by intervals of 60 s, were requested. Two independent raters visually determined the onset and offset of each MVC. The agreement between raters on the quality of the signals was analyzed both qualitatively (visual inspection) and quantitatively (signal-to-noise ratio, SNR). The reliability of integral and median frequency (MDF) of sEMG signals during MVC was analyzed using intraclass correlation coefficient (ICC) models (ICC_2,1 , ICC_2,3 ) and repeated measures analysis of variance.

RESULTS

A total of 58 women (mean age of 54 years) and two independent raters participated in the analyses. Of the total, 22 (37.9%) were considered of high quality by both raters and the SNR ranged 34.3-22.2 decibels (dB). The agreement of qualitative visual evaluation of the sEMG signal was fair (Cohen's κ = 0.306 [0.148; 0.463]). Intrarater and interrater reliability were excellent for the average of the three MVC, both for integral (ICC_2,3  = 0.884 [0.821; 0.925]; ω²  = -0.006, p = 0.558) and MDF (ICC_2,3  = 0.998 [0.998; 0.999]; ω²  = -0.009, p = 0.992).

CONCLUSION

Qualitative visual analysis of the sEMG signal presents fair interrater agreement and reflects the SNR. Visual determination of the onset and offset of the MVC of PFM using the standard interface of the sEMG software has excellent reliability for determination of muscle activation variables.

Effect of BoNT/A in the Surface Electromyographic Characteristics of the Pelvic Floor Muscles for the Treatment of Chronic Pelvic Pain

Chronic pelvic pain (CPP) is a complex condition with a high economic and social burden. Although it is usually treated with botulinum neurotoxin type A (BoNT/A) injected into the pelvic floor muscles (PFM), its effect on their electrophysiological condition is unknown. In this study, 24 CPP patients were treated with BoNT/A. Surface electromyographic signals (sEMG) were recorded at Weeks 0 (infiltration), 8, 12 and 24 from the infiltrated, non-infiltrated, upper and lower PFM. The sEMG of 24 healthy women was also recorded for comparison. Four parameters were computed: root mean square (RMS), median frequency (MDF), Dimitrov’s index (DI) and sample entropy (SampEn). An index of pelvic electrophysiological impairment (IPEI) was also defined with respect to the healthy condition. Before treatment, the CPP and healthy parameters of almost all PFM sides were significantly different. Post-treatment, there was a significant reduction in power (<RMS), a shift towards higher frequencies (>MDF), lower fatigue index (<DI) and increased information complexity (>SampEn) in all sites in patients, mainly during PFM contractions, which brought their electrophysiological condition closer to that of healthy women (<IPEI). sEMG can be used to assess the PFM electrophysiological condition of CPP patients and the effects of therapies such as BoNT/A infiltration.

Pelvic Floor Physical Therapy for Pelvic Floor Hypertonicity: A Systematic Review of Treatment Efficacy

INTRODUCTION

Hypertonicity of the pelvic floor (PFH) is a disabling condition with urological, gynecological and gastrointestinal symptoms, sexual problems and chronic pelvic pain, impacting quality of life. Pelvic floor physical therapy (PFPT) is a first-line intervention, yet no systematic review on the efficacy of PFPT for the treatment of PFH has been conducted.

OBJECTIVES

To systematically appraise the current literature on efficacy of PFPT modalities related to PFH.

METHODS

PubMed, Embase, Emcare, Web of Science, and Cochrane databases were searched from inception until February 2020. A manual search from reference lists of included articles was performed. Ongoing trials were reviewed using clinicaltrial.gov. Randomized controlled trials (RCTs), prospective - and retrospective cohorts and case-study analyses were included. Outcome measures were pelvic floor muscle tone and function, pain reports, sexual function, pelvic floor symptom scores, quality of life and patients' perceived effect.

RESULTS

The literature search resulted in 10 eligible studies including 4 RCTs, 5 prospective studies, and 1 case study published between 2000 and 2019. Most studies had a high risk of bias associated with the lack of a comparison group, insufficient sample sizes and non-standardized interventions. Six studies were of low and 4 of medium quality. All studies were narratively reviewed. Three of 4 RCTs found positive effects of PFPT compared to controls on five out of 6 outcome measures. The prospective studies found significant improvements in all outcome measures that were assessed. PFPT seems to be efficacious in patients with chronic prostatitis, chronic pelvic pain syndrome, vulvodynia, and dyspareunia. Smallest effects were seen in patients with interstitial cystitis and painful bladder syndrome.

CONCLUSION

The findings of this systematic review suggest that PFPT can be beneficial in patients with PFH. Further high-quality RCTs should be performed to confirm the effectiveness of PFPT in the treatment of PFH. van Reijn-Baggen DA, Han-Geurts IJM, Voorham-van der Zalm PJ, et al. Pelvic Floor Physical Therapy for Pelvic Floor Hypertonicity: A Systematic Review of Treatment Efficacy. Sex Med Rev 2021;XX:1-22.

Reliability of pelvic floor muscle surface electromyography (sEMG) recordings during synchronous whole body vibration

The primary aim of the study was to assess intraday and interday reliability of surface electromyography (sEMG) reflex activity of the pelvic floor muscles during synchronous whole-body vibration (S-WBV) of two intensities (30Hz/2mm; 40Hz/4mm) using band-stop filter and high-pass filter signal processing. The secondary aim of the study was to assess intraday and interday (test-retest) reliability of sEMG obtained from maximal voluntary contraction (MVC) test. We evaluated the intraday reliability of sEMG recordings obtained during sessions 1 and 2 performed on the same day. The sessions consisting of maximal voluntary pelvic floor muscle contraction and synchronous vibration sets with 1-hour rest in-between sessions 1 and 2 in healthy nulliparous women. The next intraday reliability was evaluated between the results of sessions 3 and 4 performed on the same day but followed at an interval of 4 weeks. to include the entire menstrual cycle. The interday reliability was determined based on the results of sessions 1 and 3 using the intraclass correlation coefficient (ICC 3,3). The intraday ICCs for band-stop filtered mean and median sEMG frequency and mean normalized sEMG_RMS amplitude of the 30Hz/2mm (ICC = 0.89–0.99) and 40Hz/4mm vibration (ICC = 0.95–0.99) indicated substantial reproducibility. The intraday reliability of high-pass filter at 100-450Hz for these parameters was also substantial (30Hz/2mm ICC of 0.92 to 0.98; 40Hz/4mm ICC of 0.88 to 0.98). The interday reliability (session 1 vs. session 3) of the mean normalized sEMG_RMS amplitude for band-stop filtered means of 40 Hz/4mm and 30Hz/2mm vibration recordings was substantial (ICC = 0.82 and 0.93). However, ICCs of the mean and median frequency were indicative of fair reliability (ICC of 0.43 to 0.59). The interday reliability of mean normalized sEMG_RMS amplitude for high-pass filter at 100-450Hz was substantial (30Hz/2mm ICC of 0.90; 40Hz/4mm ICC of 0.73) for the 30Hz/2mm S-WBV and moderate (ICC = 0.73) for the 40/4mm S-WBV. The ICCs for mean and median sEMG frequency ICCs indicated slight to fair reproducibility (ICC of 0.16 to 0.56). The intraday reliability of the strongest MVC contraction and average MVC turned out substantial (ICC = 0.91–0.98). The interday reliability coefficients of the strongest MVC contraction and average MVCs were 0.91 and 0.82, respectively. Concluded, the intraday reliability proved satisfactory for all variables; however, the interday comparison showed sufficient ICC levels only for the mean amplitude. We therefore recommend this parameter should be used when analyzing PFM sEMG recorded during vibration. ICCs of the mean and median frequency for both signal processing methods were indicative of insufficient reliability and did not reach the threshold for usefulness. Our study showed similar reliability of PFM sEMG during S-WBV in case of the two filtering methods used.

An International Continence Society (ICS) report on the terminology for pelvic floor muscle assessment

INTRODUCTION

The terminology for female and male pelvic floor muscle (PFM) assessment has expanded considerably since the first PFM function and dysfunction standardization of terminology document in 2005. New terms have entered assessment reports, and new investigations to measure PFM function and dysfunction have been developed. An update of this terminology was required to comprehensively document the terms and their definitions, and to describe the assessment method and interpretation of the finding, to standardize assessment procedures and aid diagnostic decision making.

METHODS

This report combines the input of members of the Standardisation Committee of the International Continence Society (ICS) Working Group 16, with contributions from recognized experts in the field and external referees. A logical, sequential, clinically directed assessment framework was created against which the assessment process was mapped. Within categories and subclassifications, each term was assigned a numeric coding. A transparent process of 12 rounds of full working group and external review was undertaken to exhaustively examine each definition, plus additional extensive internal development, with decision making by collective opinion (consensus).

RESULTS

A Terminology Report for the symptoms, signs, investigations, and diagnoses associated with PFM function and dysfunction, encompassing 185 separate definitions/descriptors, has been developed. It is clinically based with the most common assessment processes defined. Clarity and user-friendliness have been key aims to make it interpretable by clinicians and researchers of different disciplines.

CONCLUSION

A consensus-based Terminology Report for assessment of PFM function and dysfunction has been produced to aid clinical practice and be a stimulus for research.

Multicenter Randomized Controlled Trial of Pelvic Floor Muscle Training with a Motion-based Digital Therapeutic Device versus Pelvic Floor Muscle Training Alone for Treatment of Stress-predominant Urinary Incontinence

OBJECTIVE

To determine whether use of an intravaginal motion-based digital therapeutic device for pelvic floor muscle training (PFMT) was superior to PFMT alone in women with stress-predominant urinary incontinence (SUI).

METHODS

A multicenter, randomized-controlled trial was conducted where women with SUI or SUI-predominant mixed urinary incontinence were treated with either PFMT using the device (intervention group) or PFMT alone (control group). Primary outcomes, measured at 8 weeks, included change in Urinary Distress Inventory, short-version and improvement in the Patient Global Impression of Improvement, defined as "much better" or "very much better." Participants also completed Pelvic Organ Prolapse and Colorectal-anal Distress Inventories, Pelvic-Floor-Impact Questionnaire and a 3-day bladder diary. Primary analysis used a modified intention-to-treat approach. Statistical analysis used Student t test and χ2 test. The trial was prematurely halted due to device technical considerations.

RESULTS

Seventy-seven women were randomized, and final analysis included 61 participants: 29 in intervention and 32 in control group. There was no statistical difference in Urinary Distress Inventory, short-version scores between the intervention (-13.7 ± 18.7) and the control group (-8.7 ± 21.8; P = 0.85), or in Patient Global Impression of Improvement (intervention 51.7% and control group 40.6%; P = 0.47). Pelvic Organ Prolapse and Colorectal-anal Distress Inventories and Pelvic-Floor-Impact Questionnaire scores improved significantly more in the intervention group than the control group (all P < 0.05). Median number of SUI episodes decreased from baseline to 8 weeks by -1.7 per-day [(-3)-0] in the intervention group and -0.7[(-1)-0] in the control group, (P = 0.047).

CONCLUSIONS

In this prematurely terminated trial, there were no statistically significant differences in primary outcomes; however, PFMT with this digital therapeutic device resulted in significantly fewer SUI episodes and greater improvement in symptom-specific quality of life outcomes. A larger powered trial is underway.

The pathophysiology of stress urinary incontinence: a systematic review and meta-analysis

Introduction and hypothesis

To evaluate the evidence for pathologies underlying stress urinary incontinence (SUI) in women.

Methods

For the data sources, a structured search of the peer-reviewed literature (English language; 1960–April 2020) was conducted using predefined key terms in PubMed and Embase. Google Scholar was also searched. Peer-reviewed manuscripts that reported on anatomical, physiological or functional differences between females with signs and/or symptoms consistent with SUI and a concurrently recruited control group of continent females without any substantive urogynecological symptoms. Of 4629 publications screened, 84 met the inclusion criteria and were retained, among which 24 were included in meta-analyses.

Results

Selection bias was moderate to high; < 25% of studies controlled for major confounding variables for SUI (e.g., age, BMI and parity). There was a lack of standardization of methods among studies, and several measurement issues were identified. Results were synthesized qualitatively, and, where possible, random-effects meta-analyses were conducted. Deficits in urethral and bladder neck structure and support, neuromuscular and mechanical function of the striated urethral sphincter (SUS) and levator ani muscles all appear to be associated with SUI. Meta-analyses showed that observed bladder neck dilation and lower functional urethral length, bladder neck support and maximum urethral closure pressures are strong characteristic signs of SUI.

Conclusion

The pathology of SUI is multifactorial, with strong evidence pointing to bladder neck and urethral incompetence. While there is also evidence of impaired urethral support and levator ani function, standardized approaches to measurement are needed to generate higher levels of evidence.

The Overactive Pelvic Floor (OPF) and Sexual Dysfunction. Part 2: Evaluation and Treatment of Sexual Dysfunction in OPF Patients

INTRODUCTION

The assessment of pelvic floor muscle (PFM) overactivity is part of a comprehensive evaluation including a detailed history (medical, gynecological history/antecedent), appraisal of the psychosocial contexts of the patient, as well as a musculoskeletal and a neurological examination.

OBJECTIVES

The aims of this article are to review (i) the assessment modalities evaluating pelvic floor function in women and men with disorders associated with an overactive pelvic floor (OPF), and (ii) therapeutic approaches to address OPF, with particular emphases on sexual pain and function.

METHODS

We outline assessment tools that evaluate psychological and cognitive states. We then review the assessment techniques to evaluate PFM involvement including digital palpation, electromyography, manometry, ultrasonography, and dynamometry, including an overview of the indications, efficacy, advantages, and limitations of each instrument. We consider each instrument's utility in research and in clinical settings. We next review the evidence for medical, physiotherapy, and psychological interventions for OPF-related conditions.

RESULTS

Research using these assessment techniques consistently points to findings of high PFM tone among women and men reporting disorders associated with OPF. While higher levels of evidence are needed, options for medical treatment include diazepam suppositories, botulinum toxin A, and other muscle relaxants. Effective psychological therapies include cognitive behavioral therapy, couple therapy, mindfulness, and educational interventions. Effective physiotherapy approaches include PFM exercise with biofeedback, electrotherapy, manual therapy, and the use of dilators. Multimodal approaches have demonstrated efficacy in reducing pain, normalizing PFM tone, and improving sexual function. Multidisciplinary interventions and an integrative approach to the assessment and management of OPF using a biopsychosocial framework are discussed.

CONCLUSION

Although the efficacy of various intervention approaches has been demonstrated, further studies are needed to personalize interventions according to a thorough assessment and determine the optimal combination of psychological, physical, and behavioral modalities. Padoa A, McLean, L, Morin M, et al. The Overactive Pelvic Floor (OPF) and Sexual Dysfunction. Part 2: Evaluation and Treatment of Sexual Dysfunction in OPF Patients. Sex Med 2021;9:76-92.

Activation patterns of pelvic floor muscles in women with incontinence while running: a randomized controlled trial

INTRODUCTION AND HYPOTHESIS

Running is known to cause urinary leakage in women with stress urinary incontinence (SUI). Task-specific fiber-type recruitment while running can be estimated using wavelets. The aim of this study was to compare the effect of a new physiotherapy program including involuntary, reflexive training with a standard physiotherapy program on pelvic floor muscle (PFM) activation patterns and fiber-type recruitment behavior while running.

METHODS

In this triple-blinded randomized controlled trial, women with SUI were randomly allocated to the control group (CON), which performed a standard physiotherapy program, or the experimental group (EXP), which received additional involuntary, reflexive training. PFM electromyography (EMG) was recorded during 10 s at three running speeds and analyzed using Morse wavelets. The relative distribution of power (%) over the frequencies from 20 to 200 Hz was extracted and analyzed within six-time intervals of 30 ms. Statistical nonparametric mapping was performed to identify power spectra differences.

RESULTS

Thirty-nine (CON) and 38 (EXP) women were included. The power spectra showed no statistically significant group differences. The time intervals from 30 ms before to 30 ms after initial contact showed significantly lower intensities than the intervals from 30 to 150 ms after initial contact in the lowest and higher intensities in the highest frequencies for all running speeds and both groups.

CONCLUSIONS

Power spectra shifts toward higher frequency bands in the pre-initial contact phase could indicate a feed-forward anticipation and a muscle tuning for the expected impact of initial contact event in order to maintain continence.

Electromyography of pelvic floor muscles with true differential versus faux differential electrode configuration

INTRODUCTION AND HYPOTHESIS

In pelvic floor muscle (PFM) electromyography (EMG) two different bipolar configurations are applied: "true differential" configuration (TD) measures neuromuscular activity with two ipsilateral electrodes, whereas "faux differential" configuration (FD) has two electrodes placed on each side of the PFMs. The aim of the study was to determine possible differences and the relationship between both configurations.

METHODS

A secondary data analysis of 28 continent (CON) and 22 stress urinary incontinent (SUI) women was performed. Surface EMG was measured using a vaginal probe during maximal voluntary (MVC) and fast voluntary (FVC) contractions. TD and FD were explored with amplitude- and time-related EMG parameters, cross-correlation coefficients (R(0)) and statistical parametric mapping (SPM).

RESULTS

Of a total of 62 comparisons of EMG parameters of MVC and FVC, only one comparison showed significant differences between the two configurations (CON group, FVC_4peak TD versus FD, p = 0.015). R(0) were high in both groups for all MVC and FVC variables (R(0) ≥ 0.989). SPM detected 3 out of 28 comparisons with short (0.124-0.404 s) significant supra-threshold clusters (p < 0.025).

CONCLUSIONS

The findings suggest that TD and FD might measure neuromuscular activity almost the same. Very high cross-correlation coefficients and a very limited number of significant results from EMG parameters, as well as SPM, suggest that in the measured sample the choice of TD or FD might remain practically irrelevant. To gain further insight into the scientific and clinical relevance of choosing either of the electrode configurations, the comparisons should be re-evaluated on a sample with more severe incontinence symptoms.

Are there differences in short-term pelvic floor muscle function after cesarean section or vaginal delivery in primiparous women? A systematic review with meta-analysis

INTRODUCTION AND HYPOTHESIS

The literature presents controversial results regarding the role of delivery mode in pelvic floor muscle (PFM) function after birth. Some studies showed a greater impairment of PFM function after vaginal delivery compared with cesarean section, while others have not identified a significant difference between these two modes of delivery. This study aimed to investigate whether there was a difference in short-term PFM function after childbirth in primiparous women who underwent cesarean section compared with those who underwent vaginal delivery.

METHODS

Up to December 2018, the PubMed-MEDLINE, CINAHL, Embase, Bireme, Scopus, Web of Science, and Science Direct databases were searched. Two independent reviewers performed the selection process based on titles, abstracts, and full-text reading. Observational studies comparing PFM function after cesarean section versus vaginal delivery in primiparous women were included. PRISMA guidelines and Cochrane recommendations were followed. Methodological quality of the primary studies was assessed through the checklist proposed by the Joanna Briggs Institute for cross-sectional studies. Random effects meta-analysis was performed to synthesize evidence regarding PFM strength in primiparous woman after vaginal delivery compared with cesarean section. The GRADE approach was applied to classify the quality of the evidence.

RESULTS

Eleven studies met the inclusion criteria and were included in this review. A total of 1726 primiparous women were analyzed after childbirth. Five studies were included in the meta-analysis. No difference in PFM strength after childbirth was identified when cesarean section was compared with vaginal delivery [standardized mean difference (SMD): -0.15, 95% confidence interval (CI): -0.85 to 0.56]. Differences in PFM strength were identified when patients who underwent cesarean section were compared with those with an episiotomy or instrumented vaginal delivery (SMD: -12.51, CI 95%: -24.57 to -0.44), favoring the cesarean section group. In both cases, the quality of evidence was classified as very low because of the observational design of the included studies and population heterogeneity.

CONCLUSION

There was no difference in short-term PFM strength after childbirth between primiparous women who underwent cesarean section or vaginal delivery, as assessed through vaginal manometry. However, we identified reduced PFM strength in women who underwent an episiotomy or instrumented vaginal delivery compared with those who underwent cesarean section. Nevertheless, this conclusion should be cautiously considered as the observational design of the primary studies and possible heterogeneity among the primiparous women included in the studies contributed to reducing the quality of the evidence synthesized. Future primary studies with longitudinal designs and long-term follow-up periods are needed to strengthen the quality of evidence and provide more conclusive evidence to guide clinical practice.

Magnetomyographic Recordings of Pelvic Floor Activity During Pregnancy and Postpartum: A Novel Non-invasive Approach

The levator ani muscles (LAM) are integral to pelvic floor support and injury to this muscle complex has been associated with pelvic floor disorders, but our ability to evaluate their neuromuscular integrity is limited. During pregnancy, gravidas undergo systemic functional and anatomic modifications, including pelvic floor muscular adaptations. Magnetomyography (MMG) is a novel and non-invasive tool to passively measure the magnetic fields generated by depolarization activity of muscles and offers a unique method to evaluate the LAM. We collected serial MMG data in a pregnant woman with singleton gestation. Pregnant woman performed LAM contractions (Kegels) with intervening rest periods. Kegel signals were isolated by using the frequency dependent subtraction (SUBTR) and independent component analysis (ICA) methods. Concurrent body-surface electromyography (EMG) was used to evaluate for accessory-muscle recruitment by placing bipolar electrodes on the perineum, abdomen, and thigh. Amplitude and spectral-related indicators were computed across moderate intensity MMG Kegel epochs: root-mean square (RMS) amplitude, power spectrum density (PSD) and relative PSD (rPSD) in three frequency bands. Indicators were extracted from two pregnancy recordings and one postpartum. Parameters were represented in terms of gestation and postpartum weeks. We observed that postpartum RMS Kegel amplitudes had lower values than seen in pregnancy. Changes in spectral indicators were observed between pregnancy and postpartum.

Intraday and interday reliability of pelvic floor muscles electromyography in continent woman

AIMS

Vaginal surface electromyography (sEMG) is a tool used for the diagnosis and therapeutic intervention of urinary incontinence. Current sEMG systems differ in regard to electrode arrangement and data reproducibility. The aim of this study was to determine the intrasession, intraday, and interday reliabilities of sEMG parameters using a probe with circumferential electrode-position.

METHODS

The intrasession, intraday, and interday reliabilities of maximum isometric voluntary contractions (MVC) of the pelvic floor muscles were assessed for 19 healthy continent women. Three sEMG parameters that are used to describe muscle activity were verified: maximal EMG (EMG_max ), mean over 500 ms around EMG_max (EMG_A0.5 ), and mean over 2 seconds during MVC plateau (EMG_A2-4 ). Relative and absolute reliability parameters were calculated, and the statistical methods described by Bland and Altman were applied to the data.

RESULTS

We observed substantial reliabilities for all obtained parameters (EMG_max , EMG_A2-4 , and EMG_A0.5 ) in regard to the intrasession measurements (ICC = 0.93-0.97; CI = 0.86-0.99). Overall, the intraday reliability has been moderate (ICC = 0.64-0.75; CI = 0.27-0.90). EMG_max (ICC = 0.75; CI = 0.45-0.90) and EMG_A2-4 (ICC = 0.73, CI = 0.42-0.89) were higher than EMG_A0.5 (ICC = 0.64; CI = 0.27-0.85). However, the interday reliability was only fair for EMG_max (ICC = 0.48; CI = 0.04-0.77) and EMG_A0.5 (ICC = 0.51; CI = 0.07-0.78) but moderate for EMG_A2-4 (ICC = 0.65; CI = 0.28-0.85).

CONCLUSIONS

This intrasession, intraday, and interday reliability results are similar to the results reported in the literature using probes with longitudinally oriented bars. The mean sEMG signal over 2 seconds (EMG_A2-4 ) exhibited the highest reliability and is recommended for further studies. The interday reliability might be enhanced by considering the menstruation cycle.

Consensus for experimental design in electromyography (CEDE) project: Electrode selection matrix

The Consensus for Experimental Design in Electromyography (CEDE) project is an international initiative which aims to guide decision-making in recording, analysis, and interpretation of electromyographic (EMG) data. The quality of the EMG recording, and validity of its interpretation depend on many characteristics of the recording set-up and analysis procedures. Different electrode types (i.e., surface and intramuscular) will influence the recorded signal and its interpretation. This report presents a matrix to consider the best electrode type selection for recording EMG, and the process undertaken to achieve consensus. Four electrode types were considered: (1) conventional surface electrode, (2) surface matrix or array electrode, (3) fine-wire electrode, and (4) needle electrode. General features, pros, and cons of each electrode type are presented first. This information is followed by recommendations for specific types of muscles, the information that can be estimated, the typical representativeness of the recording and the types of contractions for which the electrode is best suited. This matrix is intended to help researchers when selecting and reporting the electrode type in EMG studies.

Electromyographic evaluation of synergist muscles of the pelvic floor muscle depending on the pelvis setting in menopausal women: A prospective observational study

BACKGROUND

Pelvic floor muscle (PFM) training is recommended to increase their strength and endurance. Muscles which act synergistically with PFM are taken into consideration in the therapeutic management of weakened PFM.

RESEARCH QUESTION

how does electromyography activity of the synergists muscle to PFM change concerning pelvis position and does the greater bioelectric activity of synergist muscles affect PFM function?

METHODS

A prospective, observational study evaluating the surface electromyography (sEMG) activity of selected synergist muscles of the PFM depending on the orientation of the pelvis. One hundred thirty-one menopausal women registered for the study were screened for inclusion and exclusion criteria, and by the results, eighty-two participants were enrolled for measurements. The comparisons of results between the values obtained in different positions of the pelvis (anterior pelvic tilt - P1, posterior pelvic tilt - P2 and neutral pelvic tilt - P3) were performed using Kruskal-Wallis test. A multivariate linear regression analysis was used to assess relationships between the bioelectrical activity of PFM and activity of all tested muscles - rectus abdominis (RA), gluteus maximus (GM), and adductor magnus (AM).

RESULTS

Higher RA, GM, AM bioelectrical activity was observed in the P2 as compared to P3 (during resting and functional PFM activity)(p < 0.05). Multivariate linear regression did not find the association between the bioelectrical activity of PFM and the activity of all synergist muscles in each position.

SIGNIFICANCE

sEMG activity of selected muscles acting synergistically with PFM differ depending on the pelvis position and is the highest in the posterior pelvic tilt. Greater activity of the synergists, resulting from the pelvic position, does not affect the myoelectric activity of PFM. It seems that muscles that act synergistically with PFM may not play such a significant role in the therapeutic management of PFM.

Pelvic floor muscle activation in stress urinary incontinent women: Impact of a distraction task

AIMS

Our purpose was to explore the involvement of cognition in voluntary and involuntary pelvic floor muscle (PFM) contraction in stress urinary incontinent women.

METHODS

PFM contraction monitored by surface electromyography (EMG) was measured without a mental distraction task (DT), and with a DT called "paced auditory serial additional test" (PASAT). Forty stress incontinent women performed voluntary contractions of the external anal sphincter (EAS), and reflex EAS contractions induced by means of coughing were studied using the external intercostal muscle (EIC) EMG pattern.

RESULTS

A DT altered PFM pre-activation when coughing: the reaction time between EIC muscle contraction and EAS contraction (called RT3) was respectively -54.94 ms (IQR -87.12; 3.12) without the PASAT and -3.99 ms (IQR: -47.92; 18.69) with a DT (P = 0.02, Wilcoxon's test). Concerning voluntary contraction, women activated their PFM sooner without than with a DT.

CONCLUSION

The PASAT altered voluntary and reflex contractions of the PFM in stress urinary incontinent women. Our study suggests that cognition plays a role in urinary pathophysiology. Future studies should investigate rehabilitation programs that consider the role of cognition in stress urinary incontinent women.

Pelvic floor muscle activity during fast voluntary contractions in continent and incontinent women

AIMS

Stress urinary incontinence (SUI) has also been attributed to a lower speed of contraction of the pelvic floor muscles (PFM). Therefore, PFM assessment and training implement fast voluntary contractions (FVC). The purpose of the study was to explore FVC regarding feasibility, on-/offset and rate of activity determination, as well as differences between continent (CON) and stress urinary incontinent (SUI) women.

METHODS

Fifty women were included and examined by means of PFM EMG during rest, maximum voluntary contractions (MVC), and five FVC. MVC-peak activity was used to normalize EMG-data. On-/offset of muscle activity was determined as mean of rectified rest activity plus 1 standard deviation. Linear regression was calculated for rate of activity from onset to peak, peak to offset, and within 200 ms after both onset and peak. Peak activity and time variables related to onset, peak, and offset were calculated.

RESULTS

On-/offsets were evaluable for 234/222 of 250 FVC by a computer-based algorithm, 16/28 on-/offsets had to be determined manually. There was no significant difference between groups (CON/SUI) regarding FVC peak (92.1/99.3 %MVC), time to peak (514.2/525.6 ms), and increase of activity (182.8/182.1 %MVC/s). The SUI group showed a significantly slower activity decrease (-120.7/-74.4 %MVC/s).

CONCLUSIONS

FVC analyses were shown to be feasible. The significant difference observed between the groups did not refer to activity increase but instead to a prolonged relaxation phase in the SUI group. This prompts to reconsider the interpretation of FVC in PFM testing and training.

Effects of different regimens for pelvic floor muscle training in young continent women: Randomized controlled clinical trial

BACKGROUND

Physical therapy is recommended as first-line treatment to urinary incontinence (UI), and pelvic floor muscles (PFM) training is one of the most used resources for this purpose, no ideal PFM training protocol has been established.

OBJECTIVES

The purpose of the present study was to verify whether more daily sessions of PFM training lead to better PFM function.

METHODS

Twenty-five young continent women volunteered and were randomly assigned to 2 different groups; group 1, in which they performed one PFM training session daily, and group 2, in which they performed 3 daily PFM training sessions. All volunteers were evaluated regarding PFM function, based on the Modified Oxford Scale, maximum voluntary contraction, with a manometer, and PFM activation, with electromyography. Both groups trained during 8 consecutive weeks and were evaluated before and after treatment. All evaluations had the reproducibility tested by intraclass correlation coefficients. Statistical analyzes included data normality (Shapiro-Wilks), intragroup (Wilcoxon) and intergroup (Mann-Whitney U) comparisons. Effect sizes were calculated to all variables analyzed. Significance level was set al p < 0.05.

RESULTS

Even though an increase in PFM strength, pressure and muscle activation was achieved by both groups (p < 0.05, effect sizes from 0.24 to 0.81), no differences between groups for any variables were detected (p > 0.05).

CONCLUSIONS

The number of daily training sessions does not interfere in the improvement of PFM function in young women without PFM dysfunction.

Characterizing pelvic floor muscles activities using magnetomyography

AIMS

To characterize levator ani muscle (LAM) activity in nulligravidas using magnetomyography (MMG) and define MMG characteristics associated with LAM activity with and without accessory muscle contributions.

METHODS

MMG data were collected from eight nulligravidas during rest and voluntary LAM contractions (Kegels) of varying intensity. We utilized simultaneous vaginal manometry and surface electromyography (sEMG) to evaluate for accessory muscle recruitment. Moderate Kegel (MK) MMG trials were sub-selected based on the presence or absence of accessory muscle interaction. Amplitude and spectral-related indicators were calculated across MK epochs: root-mean square (RMS) amplitude, percentage amplitude relative to rest, and relative power spectrum density (rPSD) in three frequency bands (low, middle, high). Ternary diagram characterized rPSD from selected Kegels and ROC analysis was performed to identify cut-points to differentiate MKs from interacting MKs.

RESULTS

Nineteen MMG recordings were obtained. Amplitude and spectral parameters were significantly different between isolated and interacting MK epochs. Mean RMS and power values of the isolated MK were, respectively, 120.66 ± 43.8 fT and 1.72 ± 1.44 (T² /Hz)*10^-28 . Amplitudes of MK were 64% and 117 higher than baseline activities for the isolated and interacting epochs, respectively. ROC curves reveled cut-off points on low and middle frequency bands that achieved perfect separation (ROC-AUC = 1.0) between isolated and interacting MK.

CONCLUSIONS

Our study demonstrates that MMG, a novel biomagnetic technique, allows precise detection and characterization of normal female pelvic floor function. Results show that isolated moderate voluntary contraction of the LAMs produces distinct MMG amplitude and spectral characteristics compared with Kegels involving co-activation of other muscle groups.

The relation of the pelvis and the perineal function in incontinent women: A neglected subject

AIMS

To Compare the angular parameters of the pelvis of continents and incontinent women and to correlate them with the electrical activity and the function of the pelvic floor muscles.

METHODS

Cross-sectional study. Incontinent and continent women, aged between 18 and 59 years. The anatomical points were marked following the SAPO protocols, the photographic records were made and analyzed through the SAPO Software. The evaluation of the function of the MPF was performed by bidigital vaginal palpation, using the PERFECT scheme. Surface electromyographic analysis was performed in dorsal decubitus and orthostasis.

RESULTS

The sample consisted of 40 women, 20 with SUI (IG) and 20 continents (CG), matched by age. The mean age in the CG was 43.5 years (SD 8.4), while in the IG it was 47.1 years (SD 7.8) (P = 0.16). The pelvic angle in the CG presented a mean of -14.3 ± 4.6 and the IG -16.6 ± 4.4 (P = 0.02). When compared to normality, IG presented an accentuation of anterior slope in both analyzed views (P = 0.01). There was a moderate correlation in the IG between the electrical activity of the basal pelvis in orthostasis and the anterior pelvic tilt angles in the right lateral views r = 0.51 (P = 0.02) and left lateral r = 0.46 (P = 0.04). No correlation was found in the CG.

CONCLUSIONS

In the present sample, incontinent women have a greater anterior slope of the pelvis, and the greater the degree of anterior slope, the greater the electrical activity of the PFM, during rest, and in orthostasis.

Functional assessment of the pelvic floor muscles by electromyography: is there a normalization in data analysis? A systematic review

ABSTRACT This study aims to evaluate the method of analysis of electromyographic data considering the functional assessment of pelvic floor muscles (PFM). We have included in our search strategy the following databases: Medline, PubMed, Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews, PEDro, and IBECS, considering articles published in the last ten years (2004-2014). The identified articles were independently examined by two evaluators, according to these inclusion criteria: (1) population: female adults; (2) PFM assessment by electromyography (EMG) with vaginal/anal probe; and (3) description of how electromyographic data analysis is performed. The Newcastle-Ottawa Scale (NOS) was used to assess the risk of bias. We identified 508 articles, of which 23 were included in the review. The data showed differences between the collection protocols, and a significant number of studies did not normalize the electromyographic data. Physiotherapists are among the clinicians who most frequently use EMG to evaluate the function and dysfunction of the neuromuscular system. Although some previous studies have provided an overview to guide the evaluator in the assessment, few succeeding studies followed their recommendations.

The evaluation of pelvic floor muscle strength in women with pelvic floor dysfunction: A reliability and correlation study

AIMS

The purposes of this study were: (i) to evaluate the reliability of vaginal palpation, vaginal manometry, vaginal dynamometry; and surface (transperineal) electromyography (sEMG), when evaluating pelvic floor muscle (PFM) strength and/or activation; and (ii) to determine the associations among PFM strength measured using these assessments.

METHODS

One hundred and fifty women with pelvic floor disorders participated on one occasion, and 20 women returned for the same investigations by two different raters on 3 different days. At each session, PFM strength was assessed using palpation (both the modified Oxford Grading Scale and the Levator ani testing), manometry, and dynamometry; and PFM activation was assessed using sEMG.

RESULTS

The interrater reliability of manometry, dynamometry, and sEMG (both root-mean-square [RMS] and integral average) was high (Lin's Concordance Correlation Coefficient [CCC] = 0.95, 0.93, 0.91, 0.86, respectively), whereas the interrater reliability of both palpation grading scales was low (Cohen's Kappa [k] = 0.27-0.38). The intrarater reliability of manometry (CCC = 0.96), and dynamometry (CCC = 0.96) were high, whereas intrarater reliability of both palpation scales (k = 0.78 for both), and of sEMG (CCC = 0.79 vs 0.80 for RMS vs integral average) was moderate. The Bland-Altman plot showed good inter and intrarater agreement, with little random variability for all instruments. The correlations among palpation, manometry, and dynamometry were moderate (coefficient of determination [r² ] ranged from 0.52 to 0.75), however, transperineal sEMG amplitude was only weakly correlated with all measures of strength (r²  = 0.23-0.30).

CONCLUSIONS

Manometry and dynamometry are more reliable tools than vaginal palpation for the assessment of PFM strength in women with pelvic floor disorders, especially when different raters are involved. The different PFM strength measures used clinically are moderately correlated; whereas, PFM activation recorded using transperineal sEMG is only weakly correlated with PFM strength. Results from perineal sEMG should not be interpreted in the context of reporting PFM strength.

What Does Electromyography Tell Us About Dyspareunia?

INTRODUCTION

Emergent evidence suggests that pelvic floor muscle (PFM) dysfunction contributes to dyspareunia, the experience of pain on vaginal penetration. Electromyography (EMG) is a valuable tool for the assessment of neuromuscular control and could be very useful in enhancing our understanding of PFM involvement in sexual function and in conditions such as dyspareunia. However, PFM EMG must be interpreted within the context of the many factors that can influence findings.

AIM

To outline the main factors to consider when evaluating PFM EMG for female sexual function and dyspareunia and to synthesize the literature in which EMG has been acquired and interpreted appropriately in this context.

METHODS

Standards for the acquisition and interpretation of EMG were retrieved and consulted. An exhaustive search of four electronic databases (Embase, CINAHL, PubMed, and PsycLit) and hand searching references from relevant articles were performed to locate articles relevant to PFM involvement in sexual function and in dyspareunia in which EMG was used as a primary outcome. Study outcomes were evaluated within the context of the appropriate application and interpretation of EMG and their contribution to knowledge.

MAIN OUTCOME MEASURES

A synthesis of the evidence was used to present the current state of knowledge on PFM involvement in sexual function and in dyspareunia.

RESULTS

Few standards documents and no practice guidelines for the acquisition and interpretation of PFM EMG are available. Some cohort studies with small samples of women have described the role of the PFMs in female sexual function. The literature on PFM involvement in dyspareunia also is limited, with outcomes suggesting that higher than normal tonic activation and higher than normal reflex responses might be present in the superficial PFM layer and might be characteristic features of dyspareunia. The data are less clear on the involvement of the deep layer of the PFMs in dyspareunia.

CONCLUSION

Guidelines for the application and interpretation of PFM EMG in the context of sexual function and dyspareunia are needed. When interpreted within the context of their strengths and limitations, EMG data have contributed valuable information to our understanding of PFM involvement in dyspareunia. The literature to date suggests that the superficial PFMs might have higher than normal tone and exaggerated responses to tactile or penetrative provocation in at least some women with dyspareunia. McLean L, Brooks K. What Does Electromyography Tell Us About Dyspareunia? Sex Med Rev 2017;5:282-294.

Crosstalk considerations in studies evaluating pelvic floor muscles using surface electromyography in women: a scoping review

PURPOSE

Surface electromyography (sEMG) using intravaginal probes is of widespread use for assessing pelvic floor muscles (PFM) activity in women. Although considered as a reliable method, its validity has been called into question due to the presence of a phenomenon called crosstalk. Crosstalk is described as the recording of sEMG activity originating from neighboring muscles rather than coming exclusively from the muscles being investigated. The purpose of this review was to provide an overview of existing literature about crosstalk during intravaginal surface electromyographic recordings.

METHODS

A scoping review was performed according to the Arksey and O'Malley framework. An electronic search was conducted on six relevant databases. Additionally, authors were directly contacted to identify grey literature. Data extraction consisted of descriptive numeric analysis as well as thematic analysis, which were conducted by two independent reviewers.

RESULTS

Forty-nine references written by 34 authors coming from 13 different countries constitute the body of evidence of the present review. Eight main themes have been identified through the thematic analysis. The included material varies greatly in terms of methodology, approach to the crosstalk problem and depth of analysis.

CONCLUSIONS

A gap in knowledge affecting the validity of the current sEMG investigation methods was identified. Literature addressing the crosstalk problem is scarce and often flawed. Definitive conclusions are regularly drawn from an insufficient basis of evidence. Further research is, therefore, deeply necessary, although it remains unclear whether this issue can be solved at all with current technology.

The effect of EMG biofeedback assisted pelvic floor muscle therapy on symptoms of the overactive bladder syndrome in women: A randomized controlled trial

AIMS

The overactive bladder syndrome (OAB) is defined as urinary urgency, usually accompanied by frequency and nocturia, with or without urgency urinary incontinence. Biofeedback-assisted pelvic muscle therapy (BAPFMT) is a first-line treatment option for OAB. The aims of this study were to determine the efficacy and effectiveness of BAPFMT on symptoms of OAB after 9 weeks of treatment and to detect changes EMG activity of individual pelvic floor muscles (PFM) with the MAPLe.

METHODS

Patients were randomly divided into an intervention group that received BAPFMT with the MAPLe or into a control group which received only toilet behavior and lifestyle instructions. The Pelvic Floor Inventories (PeLFIs), the King's Health Questionnaire (KHQ), a voiding dairy, a 24 h pad-test, and vaginal EMG registration of the pelvic floor with the MAPLe were used at inclusion and after 9 weeks follow-up to determine the effect of BAPFMT on complaints of OAB and Quality of Life (QoL).

RESULTS

Fifty-eight patients were included. The PeLFIs, KHQ, voiding dairy, and 24 h pad-test showed significant improvements in the intervention group compared to the control group in complaints of OAB and QoL. EMG activity showed significant improvements for specific individual muscles at the different sides and depths for rest, maximal voluntary contraction, and endurance.

CONCLUSIONS

EMG BAPFMT is effective in the OAB syndrome in women. It significantly reduces symptoms and complaints of OAB and increases QoL for patients. It shows that EMG changes in individual PFM, measured with the MAPLe, are relevant and related to symptom reduction.

Functional mapping of the pelvic floor and sphincter muscles from high-density surface EMG recordings

INTRODUCTION AND HYPOTHESIS

Knowledge of the innervation of pelvic floor and sphincter muscles is of great importance to understanding the pathophysiology of female pelvic floor dysfunctions. This report presents our high-density intravaginal and intrarectal electromyography (EMG) probes and a comprehensive innervation zone (IZ) imaging technique based on high-density EMG readings to characterize the IZ distribution.

METHODS

Both intravaginal and intrarectal probes are covered with a high-density surface electromyography electrode grid (8 × 8). Surface EMG signals were acquired in ten healthy women performing maximum voluntary contractions of their pelvic floor. EMG decomposition was performed to separate motor-unit action potentials (MUAPs) and then localize their IZs.

RESULTS

High-density surface EMG signals were successfully acquired over the vaginal and rectal surfaces. The propagation patterns of muscle activity were clearly visualized for multiple muscle groups of the pelvic floor and anal sphincter. During each contraction, up to 218 and 456 repetitions of motor units were detected by the vaginal and rectal probes, respectively. MUAPs were separated with their IZs identified at various orientations and depths.

CONCLUSIONS

The proposed probes are capable of providing a comprehensive mapping of IZs of the pelvic floor and sphincter muscles. They can be employed as diagnostic and preventative tools in clinical practices.

Pelvic floor muscle reflex activity during coughing - an exploratory and reliability study

OBJECTIVES

Activities that provoke stress urinary incontinence (SUI) rapidly increase the intra-abdominal pressure and the impact loading on the pelvic floor muscles (PFMs). Coughing can cause urinary leakage and is often used to test SUI. However, PFM characteristics during coughing, including their reliability, have not been investigated. Here, we used electromyography (EMG) to describe PFM pre-activity and reflexivity during coughing and examined the reliability of the measurements.

METHODS

This was an exploratory and reliability study including 11 young healthy women to characterize EMG reflex activity in PFMs during coughing. We describe 6 variables, averaged over 3 coughs per subject, and tested their reliability (intraclass correlation coefficient 3,1 [ICC(3,1)] and ICC(3,k), related standard error of measurement (SEM) and minimal difference [MD]). The variables represented the mean EMG activity for PFMs during 30-ms time intervals of pre-activity (initial time point of coughing [T0] and minus 30ms) and reflex activity (T0-30, 30-60, 60-90, 90-120 and 120-150ms after T0) of stretch-reflex latency responses.

RESULTS

The mean %EMG (normalized to maximal voluntary PFM contraction) for EMG variables was 35.1 to 52.2 and was significantly higher during coughing than for PFM activity at rest (mean 24.9±3.7%EMG; P<0.05). ICC(3,k) ranged from 0.67 to 0.91 (SEM 6.1-13.3%EMG and MD 16.7-36.8%EMG) and was higher than ICC(3,1) (range 0.40-0.77; SEM 9.0-18.0%EMG, MD 24.9-50.0%EMG).

CONCLUSIONS

PFM activity during reflex latency response time intervals during coughing was significantly higher than at rest, which suggests PFM pre-activity and reflex activity during coughing. Although we standardized coughing, EMG variables for PFM activity showed poor reliability [good to excellent ICC(3,k) and fair to excellent ICC(3,1) but high SEM and MD]. Therefore, coughing is expected to be heterogeneous, with low reliability, in clinical test situations. Potential crosstalk from other muscles involved in coughing could limit the interpretation of our results.

Pelvic floor muscle electromyography during different running speeds: an exploratory and reliability study

PURPOSE

Stress urinary incontinence (SUI) affects women of all ages including young athletes, especially those involved in high-impact sports. To date, hardly any studies are available testing pelvic floor muscles (PFM) during sports activities. The aim of this study was the description and reliability test of six PFM electromyography (EMG) variables during three different running speeds. The secondary objective was to evaluate whether there was a speed-dependent difference between the PFM activity variables.

METHODS

This trial was designed as an exploratory and reliability study including ten young healthy female subjects to characterize PFM pre-activity and reflex activity during running at 7, 9 and 11 km/h. Six variables for each running speed, averaged over ten steps per subject, were presented descriptively, tested regarding their reliability (Friedman, ICC, SEM, MD) and speed difference (Friedman).

RESULTS

PFM EMG variables varied between 67.6 and 106.1 %EMG, showed no systematic error and were low for SEM and MD using the single value model. Applying the average model over ten steps, ICC (3,k) were >0.75 and SEM and MD about 50 % lower than for the single value model. Activity was found to be highest in 11 km/h.

CONCLUSION

EMG variables showed excellent ICC and very low SEM and MD. Further studies should investigate inter-session reliability and PFM reactivity patterns of SUI patients using the average over ten steps for each variable as it showed very high ICC and very low SEM and MD. Subsequently, longer running distances and other high-impact sports disciplines could be studied.