Why are some women with pelvic floor dysfunction unable to contract their pelvic floor muscles?

Systematic Review and Meta-analysis of the Prevalence of Levator Ani Avulsion with Obstetric Anal Sphincter Injury and its Effects on Pelvic Floor Dysfunction

INTRODUCTION AND HYPOTHESIS

The objective was to evaluate the prevalence of levator ani avulsion (LAA) among primiparous women with obstetric anal sphincter injury (OASI) and how this association could affect future pelvic floor dysfunction.

METHODS

Three electronic databases (MEDLINE/PubMed/EMBASE) were searched in December 2018 and again in October 2022. Nine full-text articles were included in the analysis. The exclusion criteria were language other than English, studies not based on primiparous women only, conference abstracts, and evaluation without ultrasound or MRI.

RESULTS

The overall prevalence of LAA was 24% (95% CI: 18-30%). Those with OASI, were at a higher risk of LAA, OR 3.49 (95% CI: 1.46 to 8.35). In women with LAA + OASI versus OASI alone, Three of Five studies showed worsened AI symptoms. Three of Five studies assessing urinary incontinence (UI) reported no significant difference in UI, whereas two reported increased UI. All studies that looked at pelvic organ prolapse reported a higher incidence of symptomatic prolapse and reduced pelvic floor muscle strength in women with LAA + OASI compared with those without LAA.

CONCLUSION

Levator ani avulsion is prevalent following vaginal birth and is strongly associated with OASI. Incidence of AI does not increase in women with LAA and OASI, but they had greater symptom bother. OASI with LAA appears to increase the incidence of pelvic floor weakness and pelvic organ prolapse. There is no consensus agreement on the effect of LAA + OASI on UI.

Can the inability to contract the pelvic floor muscles influence the severity of urinary incontinence symptoms in females?

INTRODUCTION AND HYPOTHESIS

The objective was to analyze if the inability to perform a maximal voluntary contraction (MVC) of the pelvic floor muscles (PFMs) in a first assessment can influence the severity of urinary incontinence symptoms in women.

METHODS

A cross-sectional study was carried out using the medical records of women with UI who were referred for pelvic floor physiotherapy after undergoing a gynecological evaluation between May 2013 and December 2019. Records included data referring to age, body mass index (BMI), obstetric history, Modified Oxford Scale (MOS), and the final score of the International Consultation on Incontinence Questionnaire Short Form (ICIQ-SF) from a baseline assessment. Data were divided into women who were unable and those who were able to voluntarily perform an MVC of the PFMs. Statistical analysis was conducted using SPSS version 21.

RESULTS

A total of 498 medical records were analyzed and 36.3% of those women were not able to perform a PFM MVC after verbal command and digital stimulus. Homogeneity was observed among groups and no significant difference was found regarding the severity of UI symptoms when the groups were compared.

CONCLUSIONS

No association was found between the inability to contract the PFMs and the severity of UI symptoms. Other studies should be developed to better understand why some women are incapable of performing a voluntary PFM contraction. Also, it would be relevant to compare women with PFM dysfunction who are not able to contract the PFMs with healthy women with the same PFM condition to analyze whether this muscle condition could be related to dysfunctions such as UI or pelvic organ prolapse.

Pelvic Floor Muscle Training for Urinary Incontinence with or without Biofeedback or Electrostimulation in Women: A Systematic Review

To determine the effectiveness of pelvic floor muscle training (PFMT) with or without biofeedback or electrostimulation in reducing urinary incontinence and pelvic floor muscle con-traction in non-pregnant women with urinary incontinence. Methods: The following electronic databases were searched: PubMed, Cochrane Central, ClinicalTrials.gov, EU Clinical Trials Register, and sources from NICE, FDA, EMA, and SMC (articles only in English, 2000–2021). Search terms were: urinary incontinence, pelvic floor muscle training or exercises, biofeedback, electrostimulation. We used the PRISMA statement (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) for this systematic review. Relevant articles were selected, data were extracted, and quality was assessed. Data were extracted in predesigned form, followed by narrative synthesis. Results: Following the search, 15 RCTs were retrieved using the strict inclusion and exclusion criteria, assessing 2441 non-pregnant women with urinary incontinence. Of the 15 studies, 7 were low risk, 5 were medium risk, and 3 were high-risk studies. Of the 2441 patients, 970 were in PFMT, 69 were in extracorporeal magnetic innervation (ExMi) or with PFMT + BF, 30 were in electrostimulation (ES), 21 were in whole body vibration training (WBVT), 23 were in pelvic floor muscle + abdominal muscle therapy (PFM + AMT), 326 were in PFMT + biofeedback, 93 were in vaginal cones (VC), 362 were in PFMT + education, 318 were in education, and 229 were in control groups. The most often measures employed were pad tests, bladder diary, and questionnaire on the quality of life. Stress, urge and mixed urinary incontinence were studied. In all RCT, PFMT significantly reduced urinary incontinence, essentially SIU and MUI, when compared with the control group before and after treatment. Overall, out of 997 PFMT or PFMT + education patients, 504 patients (50.5%) showed improvement in urinary incontinence, and 218 became continent (21.8%) (negative pad test). In total, 62% of patients significantly reduced their urinary incontinence or cured it and improved their pelvic floor muscle contraction. All other physiotherapist techniques also significantly reduced urinary leakages, e.g., vaginal cones, biofeedback, ExMI, and WBVT when compared with the control group. There were no significant differences between these methods in reducing the severity of urinary incontinence. Conclusion: PFMT alone or with bio-feedback or electrostimulation was effective in reducing urinary incontinence and improving pelvic floor muscle contraction. PFMT when compared with other interventions such as bio-feedback, VC, and WBVT did not show significant differences but was superior to the control group. RCT studies with similar parameters used for measuring the outcomes need to be included.

The effect of group or individualised pelvic floor exercises with or without ultrasonography guidance for urinary incontinence in elderly women - A pilot study

INTRODUCTION

Pelvic floor exercises combined with patient education has shown to be a promising intervention for women suffering from urinary incontinence. This pilot study investigated the effect of patient education combined with group or individualised pelvic floor exercises, or individualised pelvic floor exercises with ultrasonography guidance.

METHODS

Thirty-three elderly women with urinary incontinency completed a block-randomised, assessor-blinded study combining patient education with 12-weeks of pelvic floor exercises either group-based or individual with or without ultrasonography guidance. Urinary incontinence symptoms were assessed using the Incontinence Impact Questionnaire-7 (IQ-7) and Urogenital Distress Inventory-6 (UDI-6). Furthermore, daily fluid intake and number of bathroom visits were recorded. Pelvic floor muscle strength was assessed using a manual squeeze test (Oxford Scale, 6-point).

RESULTS

An increase in pelvic floor strength was observed after 12 weeks for both the individual (P = 0.038) and the individual ultrasonography-guided (P = 0.01) exercise groups. However, only the latter group maintained an increased strength at the 24-week follow-up (P = 0.008). Across all groups, the intervention led to a decrease in bathroom visits (P = 0.002) that was maintained at the 24-week follow-up (P < 0.001). The interventions led to a decrease in UDI-6 both after the 12-week intervention (P = 0.009) and at the 24-week follow-up (P = 0.032).

CONCLUSIONS

These findings indicate that pelvic floor exercises together with patient education can reduce urogenital distress and bathroom visits without change in fluid intake. Furthermore, when pelvic floor exercises were conducted individually, pelvic floor strength increased, but pelvic floor strength was maintained over time only for individualised pelvic floor exercises with ultrasonography guidance.

Examination of pelvic floor muscle elasticity in patients with interstitial cystitis/bladder pain syndrome using real-time tissue elastography

INTRODUCTION AND HYPOTHESIS

The aim was to compare pelvic floor muscle (PFM) elasticity between interstitial cystitis/bladder pain syndrome (IC/BPS) patients and healthy women using real-time tissue elastography.

METHODS

The subjects were 17 IC/BPS female patients (IC/BPS group; age 34-84 years), 10 healthy middle-aged women (middle-aged group; 50-80 years), and 17 healthy young adult women (young group; 23-37 years). The target sites of elastography were the striated urethral sphincter (SUS) and adipose tissue as the reference site; muscle elasticity was calculated as the strain ratio (SR) of the SUS to the reference site. Evaluations were performed at rest and during PFM contraction. The IC/BPS group completed lower urinary tract symptom and pain questionnaires. SUS SR was compared among the three groups. SUS SR at rest and during PFM contraction was compared among the three groups with the t-test and the Wilcoxon test. Associations between questionnaire results and SUS SR were evaluated by correlation analysis.

RESULTS

There was no significant difference in age between the IC/BPS and middle-aged groups, but the young group was significantly younger than the other groups (p < 0.001). SUS SR at rest was significantly higher in the IC/BPS group than in the middle-aged (p = 0.014) and young groups (p = 0.002). Furthermore, in the IC/BPS group, there was no significant difference in SUS SR between at rest and during PFM contraction. SUS SR was not significantly correlated with questionnaire results for lower urinary tract symptoms.

CONCLUSIONS

SUS SR at rest was significantly higher in the IC/BPS group than in the young and middle-aged groups.

Mechanisms of hiatus failure in prolapse: a multifaceted evaluation

INTRODUCTION AND HYPOTHESIS

We investigated whether factors influencing pelvic floor hiatal closure are inter-related or independent, hypothesizing that (1) hiatus size is moderately correlated with levator defect, pelvic floor muscle strength, and change in hiatus size with contraction and (2) urogenital hiatus (UGH) and levator hiatus (LH) measures are similar in patients with anterior wall (AW) and posterior wall (PW) prolapse.

METHODS

This cross-sectional case-control study included subjects with AW prolapse (n = 50), PW prolapse (n = 50), and normal support (n = 50). Hiatus measurements and levator defects were assessed on MRI, and vaginal closure force was measured with an instrumented speculum. Pearson correlation coefficients and simple and multivariable linear regression models were performed.

RESULTS

During contraction, LH narrowed 47% more in the PW compared to AW group (p = 0.001). With straining, LH lengthened 34% more in the PW than AW group (p < 0.001). With straining, UGH and LH lengthening was greater by 72% and 44% in those with major compared to no/minor defect (p < 0.001 and p = 0.004). Contraction strength explained, at most, 4% of UGH (r = 0.17) or LH (r = 0.20) shortening during contraction (r = 0.17 and r = 0.20, respectively), indicating that these factors are largely independent. After controlling for prolapse size, resting UGH and levator defect status were associated with straining UGH (p < 0.001, p = 0.004), but muscle strength and resting tone were not.

CONCLUSIONS

Hiatus measures are complex and differ according to prolapse occurrence and type. They are, at best, only weakly correlated with pelvic floor muscle strength and movement during contraction.

Effect of intravaginal vibratory versus electric stimulation on the pelvic floor muscles: A randomized clinical trial

Introduction

According to the International Urogynecological Association and International Continence Society people with normal pelvic floor muscle function should have the ability to voluntarily and involuntarily contract and relax these muscles. However, many women are unaware of their pelvic floor, and it is estimated that about 30–50% do not know how to actively contract these muscles. Within this context, therapeutic strategies to improve pelvic floor muscle strength and function are particularly relevant.

Aims

To compare the use of an intravaginal vibratory stimulus (IVVS) versus intravaginal electrical stimulation (IVES) on pelvic floor muscle functionality in women with pelvic floor dysfunctions who cannot voluntarily contract these muscles.

Materials and methods

Randomized clinical trial performed at a tertiary care hospital from June 2016 to September 2017. The sample comprised adult women with pelvic floor dysfunction who were unable to contract their pelvic floor muscles voluntarily. Women with latex allergy or other allergies in the pelvic region, vaginal or urinary tract infection, gynecological cancer, significant pain on palpation, or pelvic floor training over the preceding 6 months were excluded. After baseline assessment, women that met the inclusion criteria were randomized to receive once-weekly 20-minute sessions of IVVS or IVES for 6 weeks.

Results

Twenty-one women were randomly assigned to each group; 18 completed the IVVS and 17 completed the IVES protocols. The IVVS group presented a significant increase in PFM strength in relation to the IVES group (p = 0.026). There was a significant interaction between time and type of intervention for the same variable (p = 0.008) in the IVVS group.

Conclusion

Both techniques were beneficial, but IVVS was significantly superior to IVES in improving pevic floor muscle strength. Additional studies are warranted to consolidate the utility of IVVS as a treatment modality for pelvic floor dysfunction.

Anatomic and functional evaluation of the levator ani muscle after an obstetric anal sphincter injury

PURPOSE

To study the relationship between symptoms of anal incontinence (AI) and the anatomy and functionality of the levator ani muscle in women with a history of obstetric anal sphincter injury (OASI).

METHODS

This is a cohort study including patients with OASI from 2013 to 2016. Patients were assessed by a physical examination, endoanal ultrasound using Starck Scale, perineometry and 4D transperineal ultrasound. AI in all patients was measured with the Wexner scale. Correlation between variables has been analyzed in these patients.

RESULTS

72 patients were analyzed: 28 with a IIIA degree tear, 26 with a IIIB, 13 with a IIIC and 5 with a IV. 38 patients showed a residual anal sphincter (AS) defect on endoanal ultrasound with an average Starck score of 6.5 ± 3.7. 21 patients expressed AI, with an average Wexner score of 4.1 ± 2.4. In 27 (37.5%) patients, a levator ani avulsion was observed: 17 unilateral and 10 bilateral. Patients with a levator ani defect had weaker pelvic floor muscle (PFM) function. These differences were statistically significant with perineometry (p = 0.01 and p = 0.03) but not for the Oxford test (p = 0.08). Patients with a residual AS defect as well as an injury to the levator ani muscle expressed greater AI symptomatology than patients with residual sphincter injury who maintain the integrity of the levator ani: Wexner 4.9 0.9 vs 3.3 1 (p = 0.02).

CONCLUSIONS

The PFM has correlation with AI symptom development in patients with a history of OASI. Therefore, we suggest a key role of anatomical and functional assessments of the levator ani muscle in these patients.

Association between pelvic floor muscle trauma and contraction in parous women from a general population

OBJECTIVE

To study possible associations between pelvic floor muscle contraction, levator ani muscle (LAM) trauma and/or pelvic organ prolapse (POP) ≥ Stage 2 in parous women recruited from a general population.

METHODS

This was a secondary analysis of data from a cross-sectional study of 608 parous women from a general population examined using the POP quantification system (POP-Q) and three-dimensional/four-dimensional transperineal ultrasound for identification of LAM macrotrauma (avulsion) and microtrauma (distension of levator hiatal area > 75^th percentile on Valsalva maneuver). Muscle contraction was assessed using the modified Oxford scale (MOS), perineometry and ultrasound measurement of proportional change of anteroposterior hiatal diameter and levator hiatal area at rest and on pelvic floor muscle contraction. The Mann-Whitney U-test was used to study associations between pelvic floor muscle contraction, LAM trauma and POP.

RESULTS

Women with macrotrauma (n = 113) had significantly weaker median pelvic floor muscle contraction, as measured using MOS and perineometry, than did women with an intact LAM (n = 493) (contraction strength was 1.5 (range, 0.0-5.0) vs 3.5 (range, 0.0-5.0) on MOS, and vaginal squeeze pressure was 15.0 (range, 0.0-78.0) cmH₂ O vs 28.0 (range, 0.0-129.0) cmH₂ O on perineometry; P < 0.001). This was also demonstrated by ultrasound measurement, with a proportional change in hiatal area of 19.9% (range, 4.1-48.0%) vs 34.0% (range, 0.0-64.0%) (P < 0.001) and proportional change in anteroposterior diameter of 16.2% (range, -5.7 to 42.6%) vs 26.0% (range, -3.4 to 49.4%) (P < 0.001). No statistically significant difference between women with (n = 65), and those without (n = 378), microtrauma was found after excluding women with macrotrauma. Women with POP had weaker muscle contraction than those without; in those with POP-Q ≥ 2 (n = 275) compared with those with POP-Q < 2 (n = 333), muscle contraction strength was 3.0 (range, 0.0-5.0) vs 3.5 (range, 0.0-5.0) on MOS, vaginal squeeze pressure was 21.0 (range, 0.0-98.0) cmH₂ O vs 28.0 (range, 3.0-129.0) cmH₂ O on perineometry, proportional change in hiatal area was 29.6% (range, 0.0-60.9%) vs 33.8% (range, 0.0-64.4%) and proportional change in anteroposterior diameter was 22.8% (range, -5.7 to 49.4%) vs 25.7% (range, -3.4 to 49.4%) (P < 0.001 for all).

CONCLUSIONS

LAM macrotrauma was associated with weaker pelvic floor muscle contraction measured using palpation, perineometry and ultrasound. Women with POP had weaker contraction than did women without POP. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Pelvic muscles' mechanical response to strains in the absence and presence of pregnancy-induced adaptations in a rat model

BACKGROUND

Maternal birth trauma to the pelvic floor muscles is thought to be consequent to mechanical demands placed on these muscles during fetal delivery that exceed muscle physiological limits. The above is consistent with studies of striated limb muscles that identify hyperelongation of sarcomeres, the functional muscle units, as the primary cause of mechanical muscle injury and resultant muscle dysfunction. However, pelvic floor muscles' mechanical response to strains have not been examined at a tissue level. Furthermore, we have previously demonstrated that during pregnancy, rat pelvic floor muscles acquire structural and functional adaptations in preparation for delivery, which likely protect against mechanical muscle injury by attenuating the strain effect.

OBJECTIVE

We sought to determine the mechanical impact of parturition-related strains on pelvic floor muscles' microstructure, and test the hypothesis that pregnancy-induced adaptations modulate muscle response to strains associated with vaginal delivery.

STUDY DESIGN

Three-month-old Sprague-Dawley late-pregnant (N = 20) and nonpregnant (N = 22) rats underwent vaginal distention, replicating fetal crowning, with variable distention volumes. Age-matched uninjured pregnant and nonpregnant rats served as respective controls. After sacrifice, pelvic floor muscles, which include coccygeus, iliocaudalis, and pubocaudalis, were fixed in situ and harvested for fiber and sarcomere length measurements. To ascertain the extent of physiological strains during spontaneous vaginal delivery, analogous measurements were obtained in intrapartum rats (N = 4) sacrificed during fetal delivery. Data were compared with repeated measures and 2-way analysis of variance, followed by pairwise comparisons, with significance set at P < .05.

RESULTS

Gross anatomic changes were observed in the pelvic floor muscles following vaginal distention, particularly in the entheseal region of pubocaudalis, which appeared translucent. The above appearance resulted from dramatic stretch of the myofibers, as indicated by significantly longer fiber length compared to controls. Stretch ratios, calculated as fiber length after vaginal distention divided by baseline fiber length, increased gradually with increasing distention volume. Paralleling these macroscopic changes, vaginal distention resulted in acute and progressive increase in sarcomere length with rising distention volume. The magnitude of strain effect varied by muscle, with the greatest sarcomere elongation observed in coccygeus, followed by pubocaudalis, and a smaller increase in iliocaudalis, observed only at higher distention volumes. The average fetal rat volume approximated 3 mL. Pelvic floor muscle sarcomere lengths in pregnant animals undergoing vaginal distention with 3 mL were similar to intrapartum sarcomere lengths in all muscles (P > .4), supporting the validity of our experimental approach. Vaginal distention resulted in dramatically longer sarcomere lengths in nonpregnant compared to pregnant animals, especially in coccygeus and pubocaudalis (P < .0001), indicating significant attenuation of sarcomere elongation in the presence of pregnancy-induced adaptations in pelvic floor muscles.

CONCLUSION

Delivery-related strains lead to acute sarcomere elongation, a well-established cause of mechanical injury in skeletal muscles. Sarcomere hyperelongation resultant from mechanical strains is attenuated by pregnancy-induced adaptations acquired by the pelvic floor muscles prior to parturition.

Recent Advances in Understanding Pelvic-Floor Tissue of Women With and Without Pelvic Organ Prolapse: Considerations for Physical Therapists

Pelvic organ prolapse is a fairly common condition that imposes significant symptoms, diminished quality of life, social burden, financial expense, and surgical risk on women. As evidence supporting the benefit of pelvic-floor muscle training in nonsurgical management of pelvic organ prolapse grows, physical therapists are becoming a provider of choice interacting with women affected by pelvic organ prolapse. This perspective article will review recent research on tissue characteristics of 3 key components of pelvic organ support: skeletal muscle, ligament, and vaginal wall. This information will be summarized as implications for physical therapists. An improved understanding of pelvic-floor tissue in women with and without pelvic organ prolapse will provide a more comprehensive appreciation of the interaction of multiple systems in the disorder.

Pelvic floor muscle functions are improved after successful transobturator vaginal mesh procedures

AIMS

To explore functional changes of pelvic floor muscle (PFM) after successful Perigee procedures.

METHODS

We retrospectively analyzed information from 145 women having achieved anatomic success, defined as <stage II cystocele according to the pelvic organ prolapse quantification (POP-Q) system. The investigated data included results from the POP-Q system and four-dimensional ultrasound at the preoperative and 12-month postoperative evaluations. The involuntary and voluntary PFM functions were, respectively, investigated during coughing and squeezing using the ultrasound parameters of the bladder neck distance (BND), bladder neck angle (BNA), genitohiatal distance (GHD), and genitohiatal angle.

RESULTS

Postoperatively more women displayed normal involuntary PFM function in maintaining a stable bladder neck (preoperative vs. postoperative: 4.8% vs. 22.8%, P < 0.001) and genitohiatal (preoperative vs. postoperative: 16.6% vs. 30.3%, P = 0.008) locations upon coughing and could perform voluntary PFM contractions (preoperative vs. postoperative: 49.7% vs. 64.1%, P = 0.018). Compared with preoperative manifestations, less caudal displacement of the bladder neck indicated by smaller ranges of dynamic changes in BNA following coughing (preoperative vs. postoperative: 28° vs. 12°, P < 0.001), more cranial movement of the bladder neck indicated by larger values of changes in BND following squeezing (-0.26 vs. 0.06 cm, P < 0.001), and less reduction of genitohiatal size indicated by larger values of changes in GHD following squeezing (preoperative vs. postoperative: -0.95 vs. -0.63 cm, P = 0.027) were demonstrated postoperatively.

CONCLUSIONS

Involuntary and voluntary PFM functions are improved after successful Perigee procedures. Neurourol. Urodynam. 36:380-384, 2017. © 2015 Wiley Periodicals, Inc.

Does pelvic floor muscle training augment the effect of surgery in women with pelvic organ prolapse? A systematic review of randomized controlled trials

BACKGROUND

Pelvic floor muscle training (PFMT) is often used as a treatment for pelvic organ prolapse (POP) and can improve function. However, the effectiveness of this modality as an adjunct to prolapse surgery for women with POP is unknown.

AIMS

To evaluate whether the use of pelvic floor muscle training as an adjunct to prolapse surgery is superior to surgery alone for women with pelvic organ prolapse.

METHODS

We searched PubMed, Embase, the Cochrane Library, and the Web of Science from their inception dates to June 30, 2014 for data describing randomized controlled trials (RCTs) that compare the efficacy of PFMT with or without lifestyle modification plus surgery versus surgery alone for women with POP. Additional relevant studies were identified by searching the references of retrieved articles and using Google Scholar. Two investigators independently reviewed and selected relevant studies that met the pre-specified inclusion criteria, extracted the data, and assessed the risk of bias in the included studies according to the Cochrane Handbook, version 5.1.0. Due to great heterogeneity in the choice and reporting of outcome measures and the different durations of follow-up among the studies, this analysis is confined to a qualitative systematic review.

RESULTS

Five RCTs involving 591 women were reviewed (treatment group [TG], 292 cases; control group [CG], 299 cases). Generally, the five RCTs exhibited low risk of bias. This study indicated no significant improvement in prolapse symptoms, in quality of life, or in the degree of prolapse for women with POP in the TG compared to those in the CG.

CONCLUSIONS

Insufficient evidence was found to support adding perioperative PFMT to surgery over the use of surgery alone in women undergoing surgery for POP. Adequately, powered RCTs with longer follow-up periods are required to evaluate the long-term effect of perioperative PFMT. Neurourol. Urodynam. 35:666-674, 2016. © 2015 Wiley Periodicals, Inc.