Test-retest reliability of an instrumented speculum for measuring vaginal closure force

Is the Elite Female Athlete's Pelvic Floor Stronger?

Background: Exercise can stress the pelvic floor muscles (PFMs). This study sought to assess the strength of the PFMs according to the level of physical exercise. Methods: An analytical observational study was carried out using digital palpation and dynamometry measurements to assess PF strength. Healthy nulliparous women were stratified according to physical exercise (physically active and sedentary) and level of physical exercise (elite, amateur, and sedentary). Results: Fifty-four women were analyzed, with a mean age of 25.64 (5.33) years and a BMI of 21.41 (2.96) kg/m2. Differences in the passive force and strength were observed between both groups of women (p < 0.05), and the strength was around two times higher in physically active women (p < 0.05). The strength was similar between elite female athletes and sedentary women (p > 0.05), but statistical differences were found with amateurs (p < 0.05). The PFM strength (p = 0.019) of elite female athletes (0.34 N) was almost half that of amateurs (0.63 N) and twice as strong as that of sedentary women (0.20 N). However, these differences were not significant using digital palpation (p = 0.398). Conclusions: Women who exercise generally have greater PFM strength than women who do not exercise. Physical exercise could strengthen the PFM; however, the high intensity demanded by high-level sports does not seem to proportionally increase the strength of the PFMs.

A feasibility study of three-dimensional ultrasound imaging of the vagina under distension

BACKGROUND

The distension properties of the vagina are critical to its function including support of surrounding organs, childbirth, and intercourse. It could be altered by many pathophysiological processes like pregnancy, radiotherapy, and reconstruction surgery. However, there are no clinically available diagnostic tools capable of quantifying the distension properties of the vagina.

PURPOSE

A proof-of-concept study was designed to assess the feasibility of a novel three-dimensional (3D) ultrasound imaging technique that allows quantitative evaluation of the vagina under distension.

METHODS

Patients with symptomatic pelvic organ prolapse (POP) were recruited for the study. An ultrathin, oversized bag was inserted into the vagina and filled with water using a modified urodynamics system. The instilled water volume and intravaginal pressure were continuously recorded. At maximum vaginal capacity, 3D transintroital ultrasound of the distended vagina and surrounding pelvic structures was performed. Exams were performed in duplicate for each patient, two hours apart (round A and round B). Following the development of a 3D surface model of the distended vagina from each scan, several measurements were obtained, including cross-sectional area, anteroposterior (AP) length and lateral width in the plane of minimum hiatal dimensions (PMHD), AP and lateral diameter at the pubic symphysis (PS) level, maximum and minimum diameter, and maximum vertical length. To assess repeatability between measurements in two rounds, the coefficient of variation (CV) and the intraclass correlation coefficient (ICC) were calculated for each measurement. Correlations between physical measurements including the pelvic organ prolapse quantification (POP-Q) system and vaginal diameter measurements, and obtained metrics were also assessed.

RESULTS

Sixteen patients with POP (average age 69 years) completed both rounds of imaging. There was sufficient echogenicity on 3D transintroital ultrasound of the distended vaginal wall to establish boundaries for 3D surface models of the vagina. Overall, all metrics had good or excellent reliability (ICC = 0.77-0.93, p < 0.05; CV = 3%-18%) except maximum diameter, which demonstrated only moderate reliability (ICC = 0.67, p = 0.092). Strong correlations were found between physical exam measurements including D point of POP-Q, introitus diameter and lateral diameter at apex, and maximum vaginal capacity, maximum vertical length, lateral diameter at PS, minimum diameter, and distended PMHD measurements. The results demonstrated that this system could generate 3D models of the shape of the distended vagina and provide multiple metrics that could be reliably calculated from automated analyses of the models.

CONCLUSIONS

A novel system for evaluation of the distension properties of the vagina was developed and preliminary evaluation was performed. This system may represent a technique for evaluation of the biomechanical and structural properties of the vagina.

Objective Changes in Pelvic Floor Muscle Strength and Length in Women With High-Tone Pelvic Floor Dysfunction After Pelvic Floor Physical Therapy (RELAX Trial)

IMPORTANCE

Although pelvic floor physical therapy (PFPT) is effective in treating high-tone pelvic floor dysfunction (HTPFD), data on the mechanism of improvement are limited.

OBJECTIVES

This study aimed to compare squeeze intravaginal closure force after 6 weeks of PFPT in women affected by HTPFD and, secondarily, to describe changes in levator dimensions and short-term effects of PFPT on bladder, bowel, and pain symptoms.

METHODS

We conducted a prospective cohort study of patients undergoing 6 sessions of PFPT for the diagnosis of HTPFD. At baseline, we measured intravaginal closure force using an instrumented speculum, levator hiatal dimension using a 3-dimensional endovaginal ultrasonography, and symptom severity using 3 validated questionnaires. Intravaginal closure force and symptoms were reevaluated after the second, fourth, and sixth PFPT sessions, and levator hiatus was reevaluated at the sixth session.

RESULTS

Twenty-six women were enrolled and 22 completed 6 sessions and are included in the analysis. Contrary to our hypothesis, mean ± SD vaginal closure force (N) did not demonstrate a significant change (3.27 ± 2.34 vs 3.67 ± 2.02 N, P = 0.18). However, mean levator hiatal area (cm2) increased between visit 1 (13.71 ± 1.77 cm2) and visit 6 (14.43 ± 2.17 cm2, P = 0.05), as did the transverse diameter (3.83 ± 0.03 vs 3.95 ± 0.03 cm, P = 0.04). Survey responses demonstrated significant improvements across all measures of genitourinary symptoms, pain, lower gastrointestinal symptoms and quality-of-life measures after 6 sessions of PFPT.

CONCLUSION

Although the levator hiatal area increased after 6 sessions of PFPT (suggesting muscle lengthening), we were unable to demonstrate that this changed the force generated by pelvic floor muscles as measured by a speculum.

The state of pelvic floor muscle dynamometry: A scoping review

AIMS

To discuss the advantages and limitation of the different pelvic floor muscle (PFM) dynamometers available, both in research and industry, and to present the extent of variation between them in terms of structure, functioning, psychometric properties, and assessment procedures.

METHODS

We identified relevant studies from four databases (MEDLINE, Compendex, Web of Science, and Derwent Innovations Index) up to December 2020 using terms related to dynamometry and PFM. In addition, we conducted a hand search of the bibliographies of all relevant reports. Peer-reviewed papers, conference proceedings, patents and user's manuals for commercial dynamometers were included and assessed by two independent reviewers.

RESULTS

One hundred and one records were included and 23 PFM dynamometers from 15 research groups were identified. From these, 20 were considered as clinical dynamometers (meant for research settings) and three as personal dynamometers (developed by the industry). Overall, significant heterogeneity was found in their structure and functioning, which limits development of normative data for PFM force in women. Further research is needed to assess the psychometric properties of PFM dynamometers and to standardize assessment procedures.

CONCLUSION

This review points up to the heterogeneity of existing dynamometers and methods of assessing PFM function. It highlights the need to better document their design and assessment protocol methods. Additionally, this review recommends standards for new dynamometers to allow the establishment of normalized data.

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.

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.

Design and validation of an automated dual-arm instrumented intravaginal dynamometer

AIMS

(1) To present the design of a novel intravaginal dynamometer (IVD) capable of measuring vaginal closure force on both the anterior and posterior arms, (2) to use bench testing to validate the force, speed of arm opening, and positional accuracy of load measurement along the IVD arms, and (3) to present in vivo force measurements made with this device, comparing forces measured by the anterior and posterior arms.

METHODS

IVD load measurements were validated against an Instron® Universal Tester, arm opening speeds were validated using video analysis, and position-load accuracy was validated against calibration weights. In vivo IVD data were acquired from female volunteers during passive opening and pelvic floor muscle contraction tasks. Anterior and posterior IVD arm force outcomes were compared.

RESULTS

Forces measured by the IVD and Instron® exhibited a strong linear relationship with excellent model fit. The speed control system was valid when tested under physiological loading conditions, however smaller antero-posterior opening diameters (25 and 30 mm) exhibited some error. The loading position along the IVD arms had no effect on force outcomes. In vivo data exhibited differences between force outcomes measured at the anterior and posterior aspects of the vagina during active contraction and passive elongation of the pelvic floor muscles.

CONCLUSIONS

This IVD design demonstrates valid load measurement and speed control during bench testing. Active and passive forces measured are consistent with the literature. With dual instrumented arms, this device allows for further investigation into the source of measured vaginal closure forces.

Do Measures of Muscular Fitness Modify the Effect of Intra-abdominal Pressure on Pelvic Floor Support in Postpartum Women?

OBJECTIVE

This study aimed to determine whether measures of muscular fitness modify the effect of intra-abdominal pressure (IAP) during lifting on pelvic floor support.

METHODS

Participants, primiparous women 1 year after vaginal delivery, underwent the Pelvic Organ Prolapse Quantification examination, measurement of IAP via a vaginal sensor while lifting a weighted car seat, pelvic floor muscle force assessment using an instrumented speculum, grip strength using a hand dynamometer, and trunk flexor endurance by holding an isometric contraction while maintaining a 60-degree angle to the table. We dichotomized pelvic floor support as worse (greatest descent of the anterior, posterior, or apical vagina during maximal strain at or below the hymen) versus better (all points above the hymen).

RESULTS

Of 825 participants eligible after delivery, 593 (71.9%) completed a 1-year study visit. Mean (SD) age was 29.6 (5.0) years. One year postpartum, 55 (9.3%) demonstrated worse support. There were no differences in IAP during lifting or in other measures of pelvic floor loading between women with better and worse support. In multivariable analyses, neither grip strength nor pelvic floor muscle force modified the effect of IAP on support. In women with trunk flexor endurance duration ≥13 minutes, the odds of worse support increased significantly as IAP increased. No fitness measure modified the effect of other measures of pelvic floor loading on support.

CONCLUSIONS

Primiparous women with higher IAP during lifting and greater muscular fitness did not have reduced odds of worse pelvic floor support compared with those with lower IAP at the same muscular fitness.

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.

Subsequent Use of a Pressure Sensor to Record Intra-Abdominal Pressure After Maximum Vaginal Closure Force in a Clinical Trial

Pelvic floor disorders are caused by weakening or damage to the tissues lining the bottom of the abdominal cavity. These disorders affect nearly 1 in every 4 women in the United States and symptoms that drastically diminish a patient’s quality of life. Vaginal closure force is a good measure of pelvic health, but current vaginal dynamometers were not designed for the rigors of hospital reprocessing, often failing due to sensor degradation through repeated sterilization processes. In order to obtain measurements of vaginal closure force in a large study, we designed a vaginal dynamometer that utilizes a removable intra-abdominal sensor already in production for the study. The sensor’s existing data acquisition system was modified to transmit to a tablet allowing the user to view data in real-time. The new speculum design allowed a single sensor to measure vaginal closure force before being used to collect intra-abdominal pressure data in the same study visit. The measurements taken with the new speculum were similar to measurements taken with a previously reported vaginal dynamometer.

The impact of a familiarization session on the magnitude and stability of active and passive pelvic floor muscle forces measured through intravaginal dynamometry

AIMS

The aim of this study was to investigate the impact of task familiarization on (1) the magnitude and (2) the repeatability of active and passive properties of the female pelvic floor muscles (PFMs) measured using automated intra-vaginal dynamometry.

METHODS

Women attended three laboratory sessions at one-week intervals. After receiving initial task instruction and feedback at the start of the first session, standardized instructions were given while women performed maximal effort voluntary contractions of their PFMs with the dynamometer arms open at two different diameters and kept their PFMs relaxed while the dynamometer arms opened to 40 mm at two speeds. Outcomes included baseline force, peak force, relative peak forces (N), rate of force development (N/s) and stiffness. Between session effects were tested for all outcomes using one-way ANOVAs. Intra-class correlation coefficients (ICCs) and minimal detectable change values were computed within each session and between sessions 1 and 2 and sessions 2 and 3.

RESULTS

Twenty nulliparous women (mean age = 35 ± 15 years) participated. No differences in the mean values were found across the three visits for any outcomes. Within sessions, neither ICC nor minimal detectable change differed among sessions and between-session ICC values were not different between visits 1 and 2 and visits 2 and 3.

CONCLUSIONS

There is no evidence of a familiarization effect over a two-week period on the amplitude nor repeatability of dynamometric measures of active or passive PFM properties recorded from nulliparous women.

Structural, functional, and symptomatic differences between women with rectocele versus cystocele and normal support

BACKGROUND

Prolapse of the anterior and posterior vaginal walls has been generally associated with apical descent and levator ani muscle defects. However, the relative contributions of these factors to the pathophysiology of descent in the different vaginal compartments is not well understood. Furthermore, symptoms uniquely associated with prolapse in these compartments have not been well characterized.

OBJECTIVES

The objectives of the study were to compare the associations between the following: (1) apical support, (2) levator ani muscles, and (3) pelvic floor symptoms in women with posterior-predominant prolapse, anterior-predominant prolapse, and normal support.

STUDY DESIGN

This is a cross-sectional study with 2 case arms: 60 women with posterior prolapse, 90 with anterior prolapse, and a referent control arm with 103 asymptomatic subjects with normal support, determined from pelvic organ prolapse quantification examinations. Levator muscle defects were graded from magnetic resonance imaging. Vaginal closure forces above resting were measured with an instrumented speculum during maximal contraction. Pelvic floor symptoms were measured via the Pelvic Floor Distress Inventory-Short Form.

RESULTS

Mean point C location in controls was -6.9 cm [1.5] (mean [standard deviation]); and was higher in posterior prolapse (-4.7 cm [2.7], 2.2 cm below controls) than the anterior prolapse group (-1.2 cm [4.1]; 5.6 cm below controls, P < .001 for all comparisons). Normal-appearing muscles (ie, muscle without a visible defect) occurred at similar frequencies in posterior prolapse (45%) and controls (51%, P = .43) but less often in anterior prolapse (28%, P ≤ .03 for pairwise comparisons). Major levator ani defects occurred at similar rates in women with posterior (33%) and anterior prolapse (42%, P = .27) but less often in controls (16%, P ≤ .012 for both pairwise comparisons). Similarly, there were significant differences in generated vaginal closure forces across the 3 groups, with the prolapse groups generating weaker closure forces than the control group (P = .004), but the differences between the 2 prolapse groups were not significant after controlling for prolapse size (P = .43). Pelvic floor symptoms were more severe for the posterior (mean Pelvic Floor Distress Inventory score, 129) and anterior prolapse groups (score, 128) than the controls (score, 40.2, P < .001 for both comparisons); the difference between the 2 prolapse groups was not significant (P = .83).

CONCLUSION

Posterior-predominant prolapse involves an almost 3-fold less apical descent below normal than anterior-predominant vaginal prolapse. Levator ani defects and muscle impairment also have a lower impact. Pelvic floor symptoms reflect the presence and size of prolapse more than the predominant lax vaginal compartment.

Test-retest reliability of the different dynamometric variables used to evaluate pelvic floor musculature during the menstrual cycle

OBJECTIVE

The aim of this study was to evaluate the reliability of different dynamometric variables of the pelvic floor muscles (PFM) in healthy women during different periods of menstrual cycle.

MATERIALS AND METHODS

Vaginal dynamometric equipment was developed by the authors and its reproducibility was tested. The PFM contractions of 20 healthy women were collected by two independent examiners over three consecutive weeks, always on the same day, with a seven-day interval between readings, starting from the first day after the end of the menstrual period. For the measurements, the branch of the dynamometer was positioned first on the sagittal plane and then on the frontal plane. Baseline, peak time, maximum PFM strength, impulse contraction, and average contraction force were calculated. Reproducibility was tested using the intra-class correlation coefficient (ICC) and standard error of measurement. Repeated-measures ANOVA was used to compare the data from different days.

RESULTS

For intra-day and inter-day reliability between examiners, all the parameters collected on the sagittal plane presented good and excellent reproducibility (ICC_2,1  = 0.60 to 0.98), whereas reproducibility on the frontal plane was respectively poor and excellent (ICC_2,1  = 0.23 to 0.97). The ANOVA revealed significant differences between sessions only for the impulse of contraction for the sagittal (P = 0.005) and frontal (P = 0.03) planes.

CONCLUSIONS

Time and contraction force parameters of the PFM are not influenced by hormonal alterations that occur during the menstrual cycle. The impulse of contraction was the only variable to demonstrate a significant difference between the first and second week of the data collection protocol. The baseline, maximum strength value, impulse of contraction, and average contraction force variables presented good to excellent reproducibility and can be safely used as a method of PFM evaluation.

An automated intravaginal dynamometer: Reliability metrics and the impact of testing protocol on active and passive forces measured from the pelvic floor muscles

AIMS

(1) To determine the reliability of an automated dynamometer designed to assess pelvic floor muscle (PFM) strength and resistance to passive elongation. (2) To evaluate the impact of PFM length and rate of tissue elongation on dynamometric outcomes.

METHODS

At each of two sessions, twenty nulliparous women performed three maximum voluntary contractions (MVC) of their PFMs with the dynamometer set to two different anteroposterior (AP) diameters (25 mm, 35 mm). Next, with PFMs relaxed, the arms of the dynamometer opened three times to 40 mm at two speeds (25 mm/s, 50 mm/s). Outcomes included baseline force, peak force, relative peak force, rate of force development (RFD), stiffness and stress relaxation. Repeated-measures ANOVAs were used to test trial, day, and task effects (α = 0.05), and intra-class correlation coefficients (ICCs) were computed.

RESULTS

Forces measured on MVC were higher with the larger AP diameter, and passive resistance was higher for the faster rate of tissue elongation. The between-trial reliability of all outcomes was excellent (0.82 < ICC < 0.98) for all measures except for peak force during the passive elongation task (0.56 < ICC < 0.93). Between-day reliability was good to excellent for active and passive RFD (0.75 < ICC < 0.93), stiffness (ICC = 0.77) and relative peak force (0.71 < ICC < 0.87); absolute force (0.11 < ICC < 0.85) and stress relaxation responses (0.19 < ICC < 0.98) tended to be less reliable.

CONCLUSIONS

The reliability of the dynamometer is adequate for both clinical and research applications. Relative forces were more reliable than absolute forces. Dimensions and rate of tissue elongation should be controlled and reported with all pelvic floor muscle assessments as these parameters impact outcomes.

Relationships Between 3-Dimensional Transperineal Ultrasound Imaging and Digital Intravaginal Palpation Assessments of the Pelvic Floor Muscles in Women With and Without Provoked Vestibulodynia

BACKGROUND

Digital intravaginal palpation remains the favored method for clinical assessment of pelvic floor muscle (PFM) function in women; however, there is growing interest in using transperineal ultrasound imaging (TPUSI). TPUSI does not involve vaginal penetration, making it particularly relevant for PFM assessment in women with genito-pelvic pain and penetration disorders.

AIMS

To study the relations between measures of PFM morphology and function assessed using 3-dimensional (3D) TPUSI and PFM assessment through intravaginal palpation.

METHODS

77 nulliparous premenopausal women with (n = 38) and without (n = 39) PVD participated. 3D TPUSI was used to measure levator hiatal dimensions at rest, at maximal voluntary contraction (MVC) of the PFMs, and at maximal Valsalva maneuver (MVM). Intravaginal palpation was used to assess PFM strength, PFM tone, PFM relaxation after contraction, and vaginal flexibility; each was scored using an ordinal grading scale. Ultrasound and palpation outcomes were compared using Spearman correlation coefficients and Kruskal-Wallis 1-way analyses of variance by rank.

OUTCOMES

Outcomes included ultrasound measures of the levator hiatal area, anteroposterior diameter, and left-right transverse diameter at rest, at MVC, and at MVM; raw and relative changes in hiatal dimensions between rest and MVC and between rest and MVM; and palpation measures of PFM strength, tone, and relaxation after contraction, and vaginal flexibility.

RESULTS

Weak to fair correlations were found between ultrasound and palpation measures. A smaller levator hiatus at rest was associated with greater PFM tone, less PFM relaxation, and less vaginal flexibility. Greater levator hiatal constriction and shortening of the hiatal anteroposterior diameter at MVC were associated with greater palpated PFM strength. Greater hiatal distention at MVM was associated with lower PFM tone and greater relaxation.

CLINICAL TRANSLATION

3D TPUSI and intravaginal palpation provide related but distinct information about PFM function in young women with and without PVD with high functioning PFMs.

STRENGTHS AND LIMITATIONS

This was the first study to compare PFM assessment using 3D TPUSI and intravaginal palpation in nulliparous premenopausal women. A main strength of the study was the inclusion of women with PVD and asymptomatic controls, which provided a wide range in outcomes because differences in PFM morphology and function exist between women with and without PVD. The lack of inclusion of older women and women with weaker and/or hypotonic PFMs limits the generalizability of the findings.

CONCLUSION

Although TPUSI has several advantages, including painless application, it is not recommended as a replacement for digital palpation in the clinical assessment of PFM function. Thibault-Gagnon S, Goldfinger C, Pukall C, et al. Relationships Between 3-Dimensional Transperineal Ultrasound Imaging and Digital Intravaginal Palpation Assessments of the Pelvic Floor Muscles in Women With and Without Provoked Vestibulodynia. J Sex Med 2018;15:346-360.

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.

Intra and inter-rater reliability study of pelvic floor muscle dynamometric measurements

OBJECTIVE:

The aim of this study was to evaluate the intra and inter-rater reliability of pelvic floor muscle (PFM) dynamometric measurements for maximum and average strengths, as well as endurance.

METHOD:

A convenience sample of 18 nulliparous women, without any urogynecological complaints, aged between 19 and 31 (mean age of 25.4±3.9) participated in this study. They were evaluated using a pelvic floor dynamometer based on load cell technology. The dynamometric evaluations were repeated in three successive sessions: two on the same day with a rest period of 30 minutes between them, and the third on the following day. All participants were evaluated twice in each session; first by examiner 1 followed by examiner 2. The vaginal dynamometry data were analyzed using three parameters: maximum strength, average strength, and endurance. The Intraclass Correlation Coefficient (ICC) was applied to estimate the PFM dynamometric measurement reliability, considering a good level as being above 0.75.

RESULTS:

The intra and inter-raters' analyses showed good reliability for maximum strength (ICC_intra-rater1=0.96, ICC_intra-rater2=0.95, and ICC_inter-rater=0.96), average strength (ICC_intra-rater1=0.96, ICC_intra-rater2=0.94, and ICC_inter-rater=0.97), and endurance (ICC_intra-rater1=0.88, ICC_intra-rater2=0.86, and ICC_inter-rater=0.92) dynamometric measurements.

CONCLUSIONS:

The PFM dynamometric measurements showed good intra- and inter-rater reliability for maximum strength, average strength and endurance, which demonstrates that this is a reliable device that can be used in clinical practice.

Validity and reliability of an instrumented speculum designed to minimize the effect of intra-abdominal pressure on the measurement of pelvic floor muscle strength

BACKGROUND

Measurements of pelvic floor muscle strength are contaminated by crosstalk from intra-abdominal pressure. We tested an improved instrumented speculum designed to minimize this crosstalk. The hypotheses were that the speculum yields: 1) maximum vaginal closure forces unrelated to intra-abdominal pressure, 2) discriminatory validity between women with strong vs. weak pelvic floor muscles, and 3) acceptable test-retest reliability.

METHODS

Maximum voluntary vaginal closure force was measured in 40 incontinent women (20-77 years) on two visits spaced one month apart. At the baseline visit, intra-abdominal pressure was also estimated via intra-vesical catheterization during the vaginal closure force measurement. Subjective estimate of pelvic floor muscle strength was also assessed using digital palpation by a skilled examiner to determine group placement as "strong" (n=31) or "weak" (n=9).

FINDINGS

Vaginal closure force was not significantly correlated with intra-abdominal pressure (r=-.26, P=.109). The groups with subjectively scored strong and weak pelvic floor muscles differed significantly by mean [SD] maximum vaginal closure force (3.8 [1.7] vs. 1.9 [0.8] N respectively, P<.01.) Across both time points the mean vaginal closure force was 3.42 [1.67] N with a range of .68 to 9.05 N. Mean Visit 1 and Visit 2 vaginal closure force scores did not differ (3.41 [1.8] and 3.42 [1.6] N, respectively). The vaginal closure force repeatability coefficient was 3.1N.

INTERPRETATION

The improved speculum measured maximum vaginal closure force without evidence of crosstalk from intra-abdominal pressure, while retaining acceptable discriminant validity and repeatability.

Length tension function of puborectalis muscle: implications for the treatment of fecal incontinence and pelvic floor disorders

BACKGROUND/AIMS

External anal sphincter (EAS) and puborectalis muscle (PRM) play important role in anal continence function. Based on length-tension measurement, we recently reported that the human EAS muscle operates at short sarcomere length under phys-iological conditions. Goal of our study was to determine if PRM also operates at the short sarcomere length.

METHODS

Length-tension relationship of the PRM muscle was studied in vivo in 10 healthy nullipara women. Length was altered by vagi-nal distension using custom-designed probes of 5, 10, 15, 20, 25 and 30 mm diameters as well as by distending a poly-ethylene bag with different volumes of water. Probes were equipped with a reverse perfuse sleeve sensor to measure vaginal pressure (surrogate of PRM tension). PRM electromyogram (EMG) was recorded using wire electrodes. Three-dimensional ultra-sound images were obtained to determine effect of vaginal distension on PRM length.

RESULTS

Ultrasound images demonstrate distension volume dependent increase in PRM length. Rest and squeeze pressures of vaginal bag increased with the increase in bag volume. Similarly, the change in vaginal pressure, which represents the PRM contraction increased with the increase in the probe size. Increase in probe size was not associated with an increase in EMG activity (a marker of neural drive) of the PRM.

CONCLUSIONS

Probe size dependent increase in PRM contraction pressure, in the presence of constant EMG (neural input) proves that the hu-man PRM operates at short sarcomere length. Surgically adjusting the PRM length may represent a novel strategy to improve treat anal continence and possibly other pelvic floor disorders.(J Neurogastroenterol Motil 2014;20:539-546).

Does age affect visualization of the levator ani in nulliparous women?

INTRODUCTION AND HYPOTHESIS

Our aim was to assess whether differences in the ages of nulliparous women affect: (1) interobserver reliability, and (2) visualization of the levator ani (LA) muscle subdivisions in nulliparous women using 3D endovaginal ultrasound (3D-EVUS).

METHODS

This was a cross-sectional study. Community-dwelling nulliparous women ages 21-70 years were recruited. Participants underwent a standard examination and a 3D-EVUS. LA subdivisions of interest included the puboperinealis, puboanalis, pubococcygeus, puborectalis, and ileococcygeus muscles. Each ultrasound (US) volume was scored using a validated scale and assessed by two observers. Defect severity was scored for each muscle from 0 (no defect) to 6 (complete muscle loss). A summed score of the two sides was grouped as normal (0), minor (1-3), or major (4-6). Bias was examined using Bland-Altman plots. Intraclass coefficients were calculated to report agreement of total scores. Spearman's rank correlation was used to evaluate the association between age and LA scores.

RESULTS

Eighty nulliparous women were evaluated. Exact agreement for bilateral scoring of each LA subdivision ranged from 82 % to 84 %. Bilateral scoring of the puboperinealis, puborectalis, and ileococcygeus showed moderate to substantial agreement. Bilateral scores of the puboperinealis demonstrated substantial agreement between observers, with an ICC of 0.8 and a mean difference of -0.2 using the Bland-Altman analysis. When women were analyzed by age decade, reader agreement was overall good to excellent. There was no significant correlation between increasing age and total LA muscle scores (r = 0.179, p = 0.113).

CONCLUSIONS

Interobserver reliability or visualization of the LA muscle in nulliparous women was not affected by a woman's age.

Evaluation of strength and irradiated movement pattern resulting from trunk motions of the proprioceptive neuromuscular facilitation

Introduction. The proprioceptive neuromuscular facilitation (PNF) is a physiotherapeutic concept based on muscle and joint proprioceptive stimulation. Among its principles, the irradiation is the reaction of the distinct regional muscle contractions to the position of the application of the motions. Objective. To investigate the presence of irradiated dorsiflexion and plantar flexion and the existing strength generated by them during application of PNF trunk motions. Methods. The study was conducted with 30 sedentary and female volunteers, the PNF motions of trunk flexion, and extension with the foot (right and left) positioned in a developed equipment coupled to the load cell, which measured the strength irradiated in Newton. Results. Most of the volunteers irradiated dorsal flexion in the performance of the flexion and plantar flexion during the extension motion, both presenting an average force of 8.942 N and 10.193 N, respectively. Conclusion. The distal irradiation in lower limbs became evident, reinforcing the therapeutic actions to the PNF indirect muscular activation.

A comparison of the effect of age on levator ani and obturator internus muscle cross-sectional areas and volumes in nulliparous women

AIMS

Functional tests have demonstrated minimal loss of vaginal closure force with age. So we tested the null hypotheses that age neither affects the maximum cross-sectional area (CSA) nor the volume of the levator muscle. Corresponding hypotheses were also tested in the adjacent obturator internus muscle, which served as a control for the effect of age on appendicular muscle in these women.

METHODS

Magnetic resonance images of 15 healthy younger (aged 21-25 years) and 12 healthy older nulliparous women (aged >63 years) were selected to avoid the confounding effect of childbirth. Models were created from tracing outlines of the levator ani muscle in the coronal plane, and obturator internus in the axial plane using 3D Slicer v. 3.4. Muscle volumes were calculated using Slicer, while CSA was measured using Imageware™ at nine locations. The hypotheses were tested using repeated measures analysis of variance with P < 0.05 being considered significant.

RESULTS

The effect of age did not reach statistical significance for the decrease in levator ani muscle maximum CSA or the decrease in volume (4.3%, P = 0.62 and 10.9%, 0.12, respectively). However, age did significantly adversely decrease obturator internus muscle maximum CSA and volume (24.5% and 28.2%, P < 0.001, respectively). Significant local age-related changes were observed dorsally in both muscles.

CONCLUSIONS

Unlike the adjacent appendicular muscle, obturator internus, the levator ani muscle in healthy nullipara does not show evidence of significant age-related atrophy.

Urethral closure pressures among primiparous women with and without levator ani muscle defects

INTRODUCTION AND HYPOTHESIS

Vaginal birth is an established risk factor for levator ani (LA) defects and incontinence. We hypothesized an association between urethral pressure profiles and LA defects.

METHODS

One hundred sixty primiparous women, 9-12 months postpartum, were assessed with MRI for LA defects, urodynamic testing, and instrumented speculum for vaginal closure force. Urodynamic testing included resting maximal urethral closure pressure (MUCP) and urethral closure pressure with a pelvic floor contraction or Kegel (KUCP). We examined the relationships between MUCP, KUCP, LA defect status, and vaginal closure force.

RESULTS

There was no significant association between MUCP or KUCP in women with and without LA defects (p = 0.94, p = 0.95). Additionally, there was no correlation between MUCP and vaginal closure force (r = 0.06, p = 0.41), and a weak correlation between KUCP and vaginal closure force (r = 0.20, p = 0.01).

CONCLUSIONS

In this population, urethral pressure profiles are unrelated to LA defect status after vaginal birth, indicating that the mechanism responsible for LA damage spares the urethra.

Feasibility of a longitudinal study of women anticipating first pregnancy and assessed by multiple pelvic exams: recruitment and retention challenges

OBJECTIVE

To better understand the relationship between childbirth and pelvic floor disorders the ideal study design would begin with data collection prior to but close in time to first pregnancy and follow participants through postpartum. We conducted a feasibility study to determine the following: a) whether women desiring to get pregnant would agree to pre-pregnancy data collection including a one-time urethral catheter measure and repeat pelvic exams to ascertain a baseline within 6 months of pregnancy; b) effectiveness of various recruitment and retention methods, c) number achieving pregnancy, and then d) number expressing willingness to continue follow-up through pregnancy and postpartum.

METHODS

Advertising included newspaper ads, targeted emails and flyers. Post-enrollment, four data collection visits were scheduled and occurred every 6 months or until pregnant. If pregnancy occurred, women were asked to indicate their willingness to continue assessments.

RESULTS

The most successful advertising strategy for both recruitment and retention was local newspaper ads. Ninety-four women inquired about the study, 30 enrolled. Post-baseline retention was 23 women at 6 months, 17 at 12 months, and 13 at 18 months. Nine of the 30 women achieved pregnancy; two remained eligible and willing to participate through pregnancy and postpartum.

CONCLUSIONS

This study provides data on feasibility of recruiting women to establish near-pregnancy clinical baseline measures that include pelvic exams. Close to 30% reached pregnancy within 2 years of study start and within 6 months of most recent pelvic exam measure. Of those who became pregnant, 22% expressed willingness to continue follow-up into the childbearing year.

Vaginal birth and de novo stress incontinence: relative contributions of urethral dysfunction and mobility

OBJECTIVE

To evaluate the relative contributions of urethral mobility and urethral function to stress incontinence.

METHODS

This was a case-control study with group matching. Eighty primiparous women with self-reported new stress incontinence 9-12 months postpartum were compared with 80 primiparous continent controls to identify impairments specific to stress incontinence. Eighty nulliparous continent controls were evaluated as a comparison group to allow us to determine birth-related changes not associated with stress incontinence. Urethral function was measured with urethral profilometry, and vesical neck mobility was assessed with ultrasound and cotton swab test. Urethral sphincter anatomy and mobility were evaluated using magnetic resonance imaging. The associations among urethral closure pressure, vesical neck movement, and incontinence were explored using logistic regression.

RESULTS

Urethral closure pressure (+/-standard deviation) in primiparous incontinent women (62.9+/-25.2 cm H(2)0) was lower than in primiparous continent women (83.9+/-21.0, P<.001; effect size d=0.91) who were similar to nulliparous women (90.3+/-25.0, P=.091). Vesical neck movement measured during cough with ultrasonography was the mobility measure most associated with stress incontinence; 15.6+/-6.2 mm in incontinent women compared with 10.9+/-6.2 in primiparous continent women (P<.001, d=0.76) or nulliparas (9.9+/-5.0, P=.322). Logistic regression disclosed the two-variable model (max-rescaled R(2)=0.37, P<.001) was more strongly associated with stress incontinence than either single-variable model, urethral closure pressure (R(2)=0.25, P<.001) or vesical neck movement (R(2)=0.16 P<.001).

CONCLUSION

Lower maximal urethral closure pressure is the measure most associated with de novo stress incontinence after first vaginal birth followed by vesical neck mobility.

LEVEL OF EVIDENCE

II.