Pelvic floor muscle function in continent and stress urinary incontinent women using dynamometric measurements

AIMS: To compare the pelvic floor muscle (PFM) function in continent and stress urinary incontinent women using dynamometric measurements. METHODS: Thirty continent women and 59 women suffering from stress urinary incontinence (SUI), aged between 21 and 44 and parous, participated in the study. An instrumented speculum was used to assess the static parameters of the PFM: (1) passive force at 19 and 24 mm of vaginal aperture (antero-posterior diameter), (2) maximal strength in a self-paced effort at both apertures, (3) rate of force development and number of contractions during a protocol of rapidly repeated 15-sec contractions, and lastly (4) absolute endurance recorded over a 90-sec period during a sustained maximal contraction. The parameters described in the two latter conditions were assessed at the aperture of 19 mm. Analyses of covariance were used to control the confounding variables of age and parity when comparing the PFM function in the continent and incontinent women. RESULTS: The continent women demonstrated higher passive force at both openings and a higher absolute endurance as compared to the incontinent women (P < or = 0.01). In the protocol of rapidly repeated contractions, the rate of force development and number of contractions were both lower in the incontinent subjects (P < or = 0.01). The differences between the two groups for maximal strength at the 19- and 24-mm apertures did not reach the statistically significant level. CONCLUSIONS: The PFM function is impaired in incontinent women. The assessment of PFM should not be restricted to maximal strength. Other parameters that discriminate between continent and incontinent women need to be added to the PFM assessment in both clinical and research settings.     

Reliability of dynamometric measurements of the pelvic floor musculature

AIMS: The objective of this study was to evaluate the reliability of strength and endurance dynamometric measurements of the pelvic floor musculature (PFM). MATERIALS AND METHODS: Twenty-nine female participants, primipara and multipara, aged between 27 and 42 and presenting different severity levels of stress urinary incontinence (SUI), participated in the study. They were evaluated using a new pelvic floor dynamometer, an instrumented speculum based on strain-gauged technology. Strength and endurance evaluations were repeated in three successive sessions, each followed by a 4-week period. Maximal strength values were recorded at three dynamometer openings (5 mm, 1 cm, and 1.5 cm between the two dynamometer branches). The maximal rate of force development (MRFD) and percentage of strength lost after 10 and 60 sec were computed from the endurance trial. The generalizability theory was applied to estimate the reliability of the PFM measurements. The reliability was quantified by the index of dependability and the corresponding standard error of measurement (SEM) for one and the mean of three trials performed in one session for the strength measurements and one trial completed in one session for the MRFD and endurance measurements. RESULTS: For the maximal strength measurements, the largest coefficient of dependability was obtained at the 1 cm opening, with a value of 0.88. The corresponding SEM reached 1.49 N. The reliability of the MRFD was also very good with a coefficient of 0.86 and an SEM of 0.056 N/sec. The reliability was minimally affected by the number of trials. The strength loss measurements at 10 and 60 sec were unreliable, with coefficient values of 0.38 and 0.10, respectively. CONCLUSIONS: The results of the present study indicate that the reliability of the strength parameters (maximal strength and MRTD measurements) was high enough for future investigations on pelvic floor rehabilitation programs.     

Pelvic floor maximal strength using vaginal digital assessment compared to dynamometric measurements

AIM: To compare vaginal digital assessment with dynamometric measurements for determining the maximal strength of the pelvic floor muscles (PFM). MATERIALS AND METHODS: Eighty-nine women aged between 21 and 44 participated in the study. An experienced physiotherapist evaluated the maximal strength of the PFM of these women using the modified Oxford grading system (six categories, range 0-5) and dynamometric measurements. The mean maximal forces obtained for all women with the instrumented speculum for each category of digital assessment were compared using ANOVAs. Spearman's rho coefficients were calculated to assess the correlation between the dynamometric and the digital assessments. RESULTS: According to their symptoms and pad test results, 30 women were continent and 59 had stress urinary incontinence (SUI). Based on dynamometric measurements, important overlaps were observed between each category of digital assessment. The ANOVAs indicated that force values differ across categories (F = 10.08; P < 0.001), although contrast analyses revealed no differences in the mean maximal forces between adjacent digital-assessment categories (1-2, 2-3, 3-4, 4-5). Mean force values differed significantly only between non-adjacent levels in digital assessment, for example, between 1 and 3; 1 and 4; 1 and 5; 2 and 4; 2 and 5 (P < 0.05). Significant correlations were found between the two measurements with coefficients of r = 0.727, r = 0.450, and r = 0.564 for continent, incontinent, and all women, respectively (P < 0.01). CONCLUSIONS: Even if the dynamometric mean forces of the PFM increased across subsequent categories of digital assessment, the force values between two adjacent categories do not differ. This limitation of digital assessment should be considered by clinicians and researchers when choosing treatment orientation and evaluating treatment outcomes.     

Pelvic floor muscle exercise for the treatment of female stress urinary incontinence: II. Validity of vaginal pressure measurements of pelvic floor muscle strength and the necessity of supplementary methods for control of correct contraction

The present investigation comprises three methodological studies concerning vaginal pressure measurements of pelvic floor muscle (PFM) strength. Vaginal pressure was measured by a balloon (6.7 ± 1.7 cm) connected by a catheter to a pressure transducer. The balloon was placed with the middle of the balloon 3.5 cm inside the introitus vagina. In fourty-seven women, mean age 44.9 years (24–64), observation of movement of the vaginal catheter during PFM contraction verified 7 inconclusive results from perineovaginal palpation and was the most valid way to distinguish between correct and incorrect PFM contraction. Vaginal pressure rise was obtained regardless of correct or incorrect PFM contraction, showing that vaginal pressure is not specific for PFM contraction. However, as the action of the PFM is elevation, a simultaneous inward movement of the vaginal catheter is present only during correct PFM contraction. Degree of influence of various muscle groups on vaginal pressure was investigated in 14 women using two different balloons, one having a silicone reinforcement of the tip. It was found that the median contraction value of muscles other than the PFM did not exceed contraction of PFM alone. No significant difference was observed using the two types of balloons. In three physical therapists EMG activity of the lower m. rectus abdominis was recorded during maximal PFM contractions. A rise in EMG activity always occurred during maximal contractions even if the women actively tried to relax the abdominal muscles. It is concluded that vaginal pressure measurement of PFM strength is valid with simultaneous observation of inward movement of the balloon catheter. Vaginal pressure rise due to simultaneous contraction of other muscles is probably not larger than pressure rise due to intended PFM contraction. Reinforced balloon tip will not change pressure recording, and rise in EMG activity of lower abdominal muscles seems unavoidable during maximal PFM contraction.     

Pressure measurements during pelvic floor muscle contractions: The effect of different positions of the vaginal measuring device

The purpose of the present investigation was to assess whether different positions of the vaginal measuring device affect the pressure readings during pelvic floor muscle (PFM) contraction. Twelve women with stress urinary incontinence (SUI) participating in a PFM exercise program, volunteered for the study. The diagnosis of SUI was based on urodynamic investigation and pad test. The mean age of the women was 40.9 years (24–50). The women performed three PFM contractions with a vaginal balloon placed in four different positions: 1) against the vaginal vault and in the posterior fornix, 2) in the proximal upper third of the vagina, 3) with the middle of the balloon 3.5 cm from the introitus vagina and 4) with half of the balloon outside the introitus vagina. The results demonstrated significant differences between recordings from the four vaginal positions: position 1, median pressure 5 cm H₂O; position 2, 9 cm H₂O; position 3, 15 cm H₂O; and position 4, 8 cm H₂O. It is concluded that the position of the vaginal device affects the results. This may be one important factor which could explain the variability of vaginal pressure recordings during PFM contractions. For most women the highest pressure was recorded in position 3. © 1992 Wiley-Liss, Inc.     

Differences in muscle activation patterns during pelvic floor muscle contraction and Valsalva maneuver

AIMS: To investigate the different muscle activation patterns around the abdomino-pelvic cavity in continent women and their effect on pressure generation during a correct pelvic floor muscle (PFM) contraction and a Valsalva maneuver. METHODS: Thirteen continent women were assessed. Abdominal, chest wall, and PFM activity and vaginal and intra-abdominal pressure (IAP), were recorded during two tasks: PFM contraction and Valsalva whilst bladder base position was monitored on trans-abdominal ultrasound. A correct PFM contraction was defined as one that resulted in bladder base elevation and a Valsalva resulted in bladder base depression. RESULTS: Comparison of the mean of the normalized EMG activity of all the individual muscle groups was significantly different between PFM contraction and Valsalva (P = 0.04). During a correct PFM contraction, the PFM were more active than during Valsalva (P = 0.001). During Valsalva, all the abdominal muscles (IO (P = 0.006), EO (P < 0.001), RA (P = 0.011)), and the chest wall (P < 0.001) were more active than during PFM contraction. The change in IAP was greater during Valsalva (P = 0.001) but there was no difference in the change in vaginal pressure between PFM contraction and Valsalva (P = 0.971). CONCLUSIONS: This study demonstrates a difference in muscle activation patterns between a correct PFM contraction and Valsalva maneuver. It is important to include assessment of the abdominal wall, chest wall, and respiration in the clinical evaluation of women performing PFM exercises as abdominal wall bracing combined with an increase in chest wall activity may cause rises in IAP and PFM descent.     

A Pilates exercise program with pelvic floor muscle contraction: Is it effective for pregnant women? A randomized controlled trial

Aims

The aim of this study was to evaluate the effectiveness of a Pilates exercise program with pelvic floor muscle (PFM) contraction compared to a conventional intervention in pregnant women.

Methods

Fifty primiparous women, without gestational alterations, were randomized to the Pilates group (n = 25) and control group (n = 25). Interventions for both groups consisted of twice‐weekly sessions of 1 h each during the period between the 14‐16th and 32‐34th gestational weeks. The Pilates group performed a Pilates exercises program with the addition of voluntary PFM contraction. Mat‐based Pilates exercises were performed involving movement of the upper limbs, lower limbs and trunk in all sessions. The Control group walked for 10 min and performed strengthening exercises of the lower limbs, upper limbs, and trunk with resistance from an elastic band and body weight. Each woman was evaluated by an unblinded physiotherapist before and after intervention for primary (PFM strength using a manometer) and secondary (PFM strength using Oxford Scale, endurance and repeatability) outcomes. Covariance analysis (ANCOVA) was used to compare the groups using the baseline values as a covariate.

Results

Thirty‐six women were included in the analysis. There were no differences between the groups for manometry. An increase in the PFM strength, endurance, and repeatability was only observed in the Pilates group. In addition, the Pilates group showed greater adherence to the intervention.

Conclusion

Pilates exercise program with PFM contraction is not able to change the PFM strength assessed by manometer in pregnant women, but it improved adherence to the intervention.     

Abnormal pelvic response to cough in women with stress urinary incontinence

AIMS: To assess how muscular fatigue deteriorates the modulation of pelvic contraction during increasing cough efforts. Furthermore, we investigated the correlation between the temporal course of pelvic floor activation during cough. METHODS: Informed consent was obtained from 20 women presenting with SUI and 6 continent women (overactive bladder syndrome [OAB]). Bladder pressure (BP) and external anal sphincter electromyographic activity (EAS EMGi) were recorded concomitantly during increasing cough efforts. Modulation of pelvic contraction was assessed before and after two types of intense pelvic exercise (Exercise #1: 10 successive strong cough efforts; Exercise #2: 10 pelvic contractions followed by a maximal pelvic contraction) at 0, 200, and 400 ml of bladder filling. We have also recorded electromyographic activity of external intercostal (EIC) muscles. RESULTS: Whereas the Exercise 1 had no effect on modulation, the Exercise 2 altered significantly the modulation of pelvic contraction during increasing cough efforts (P = 0.043) only in women presenting with SUI. The bladder filling volume seems to not significantly modify this modulation (P = 0.12). Median latency between the onset of the EAS EMGi and the onset of the EIC EMGi was -470 and -60 msec in OAB group and in SUI group, respectively (P = 0.012). There was a good correlation between mean latency (default of EAS EMGi pre-activation) and an altered modulation of pelvic contraction during increasing cough efforts (P = 0.040). CONCLUSIONS: Some women with SUI exhibit an altered pattern of the PFM response during increasing coughing efforts. The lack of this modulation of PFM response to stress may be one of the pathophysiologic factors of SUI.     

Determining the optimal pelvic floor muscle training regimen for women with stress urinary incontinence

Pelvic floor muscle (PFM) training has received Level‐A evidence rating in the treatment of stress urinary incontinence (SUI) in women, based on meta‐analysis of numerous randomized control trials (RCTs) and is recommended in many published guidelines. However, the actual regimen of PFM training used varies widely in these RCTs. Hence, to date, the optimal PFM training regimen for achieving continence remains unknown and the following questions persist: how often should women attend PFM training sessions and how many contractions should they perform for maximal effect? Is a regimen of strengthening exercises better than a motor control strategy or functional retraining? Is it better to administer a PFM training regimen to an individual or are group sessions equally effective, or better? Which is better, PFM training by itself or in combination with biofeedback, neuromuscular electrical stimulation, and/or vaginal cones? Should we use improvement or cure as the ultimate outcome to determine which regimen is the best? The questions are endless. As a starting point in our endeavour to identify optimal PFM training regimens, the aim of this study is (a) to review the present evidence in terms of the effectiveness of different PFM training regimens in women with SUI and (b) to discuss the current literature on PFM dysfunction in SUI women, including the up‐to‐date evidence on skeletal muscle training theory and other factors known to impact on women's participation in and adherence to PFM training. Neurourol. Urodynam. Neurourol. Urodynam. 30:746–753, 2011. © 2011 Wiley‐Liss, Inc.     

Transabdominal ultrasound measurement of pelvic floor muscle activity when activated directly or via a transversus abdominis muscle contraction

AIMS: The purpose of the present study was to compare the effectiveness of instruction to contract the pelvic floor muscles (PFM), the transversus abdominis (TrA), and the TrA + PFM visualized as displacement of the pelvic floor by ultrasound. MATERIALS AND METHODS: Twenty female physical therapists, mean age 41.1 years (range 26-56) participated in the study. A 3.5 MHz 35 mm curved linear array ultrasound transducer (Dornier Medtech) was placed in the mid-sagittal plane immediately suprapubically, angled at 15-30 degrees from the vertical depending on subcutaneous fat and anatomical variations, to image the pelvic floor. Six trials of three maneuvers in random order were performed: contraction of PFM, TrA, and TrA + PFM. RESULTS: In spite of correct contractions assessed by palpation and clinical observation, one subject demonstrated a downward movement of the pelvic floor during PFM contraction on ultrasound. Six subjects (30%) showed a downward movement during a TrA- contraction, and two during the combined TrA + PFM contraction. Instruction to contract PFM produced significantly greater mean displacement: 11.2 mm (95% CI 7.2-15.3) than TrA 4.3 mm (95% CI -0.2-8.8), P < 0.01, and combination: 8.5 mm (95% CI 5.2-12), P = 0.04. Hence, instruction of PFM contraction produced a 61.6% greater displacement of the pelvic floor in the correct direction than a TrA contraction. CONCLUSIONS: It is concluded that ultrasound is a more valid method than palpation and clinical observation to assess PFM function, and that instruction to contract the PFM produces a significantly more effective pelvic floor muscle contraction than instruction to perform a TrA contraction.     

Evaluation of pelvic floor muscle function in a random group of adult women in Austria

Despite an increasing clinical interest in female pelvic floor function, there is a lack of data with respect to the knowledge of average adult women about the physiological role of the pelvic floor and their ability to contract pelvic floor muscles (PFM) voluntarily. It was the aim of our study to evaluate the percentage of PFM dysfunction in adult women and the impact of risk factors, such as age, body mass index (BMI), number of children delivered, and the influence of previous PFM training. A total of 343 Austrian adult women (mean age, 41.2 ± 14.6 years; range, 18–79 years), selected at random, were examined to test their ability to contract the PFM. The examination was carried out by three independent gynecologists during the course of a routine gynecological visit. The ability to contract the PFM voluntarily or involuntarily was assessed by digital intravaginal palpation with the patients in a supine position. The muscle strength was graded according to the Modified Oxford Grading Scale by Laycock. A high percentage (44.9%) of the women was not able to voluntarily perform a normal PFM contraction. In only 26.5%, an involuntary contraction of the pelvic floor was present before an increase in intra-abdominal pressure. The inability to contract the PFM did not correlate with women’s age but revealed a weak relationship with the number of childbirths and the patient’s BMI. A significant correlation was found between the Oxford Grading Scale rating and the patient’s report about previous PFM training.     

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.     

Long-term results of the pelvic floor muscle training for female urinary incontinence: an 8-year transition tree and predictive parameters

AIMS: The pelvic floor muscle (PFM) training is effective in alleviating the symptoms of urinary incontinence, but there are very few reports available on its long-term effectiveness. Therefore, 8-year follow-up data have been prospectively analyzed. MATERIALS AND METHODS: Originally 123 women with stress or mixed urinary incontinence participated in an 8-week intensive PFM training program. The training comprised repeated muscle contractions of the pelvic floor and the timely locking of the perineum. An average of 8 years (6-10) had elapsed between the time of present assessment and the completion of the original training. Seventy-nine women were subjected to the present analysis. Self-reported responses of "completely cured" and "more than 50% improved" were regarded as treatment success (TS). An 8-year transition tree and predictive parameters were analyzed. RESULTS: The success rate of the training was 39% at the 8-year follow-up. The transition tree demonstrated that the continence/incontinence status has been varying in 42% of the women, while it was stable in 58% throughout the follow-up period. The 6-year incidence and remission rates of incontinence were 34% and 18%, respectively. The higher pressure difference in the vaginal contraction strength between the baseline and strength at the end of the training is a predictive parameter of the long-term TS. CONCLUSIONS: The results suggest that the 8-year TS rate was 39% and that the altered patterns of the continence status and incidence and remission rates of incontinence were similar to those observed in the general population.     

Altered muscle activation patterns in symptomatic women during pelvic floor muscle contraction and Valsalva manouevre

AIMS: To investigate the muscle activation patterns of the abdomino-pelvic region used by incontinent women during a pelvic floor muscle (PFM) contraction and a Valsalva manouevre compared to healthy, asymptomatic subjects. METHODS: Thirteen incontinent (symptomatic) women, identified using ultrasound to be consistently depressing the bladder base during PFM contraction, and thirteen continent women (asymptomatic) able to perform an elevating PFM contraction were assessed using surface electromyography (EMG) of the PFM, abdominal and chest wall muscles and vaginal and intra-abdominal pressure (IAP) measurements during PFM contraction and Valsalva under ultrasound surveillance. RESULTS: There were no differences between groups in age, parity or BMI. There was a difference in muscle activation patterns between groups (P = 0.001). During PFM contraction the PFM were less active and the abdominal and chest wall muscles were more active in the symptomatic group. During Valsalva, the PFM and EO were more active in the symptomatic group but there was no difference in the activation of the other muscles between groups. There was a significant interaction (group x pressure) for change in IAP (P = 0.047) but no significant interaction for change in vaginal pressure (VP) (P = 0.324). CONCLUSIONS: The symptomatic women displayed altered muscle activation patterns when compared to the asymptomatic group. The symptomatic women were unable to perform a voluntary PFM contraction using a localized muscle strategy, instead activating all the muscles of the abdomino-pelvic cavity. The potential for muscle substitution strategies reinforces the need for close attention to specificity when prescribing PFM exercise programs.     

Reliability of pelvic floor muscle strength measurement in elderly incontinent women

Pelvic floor muscles (PFM) play an important role in maintaining urinary continence with increasing age. Therefore, their contractile properties need to be evaluated. The aim of the study was to examine the reliability and correlation of simple techniques to measure PFM strength in elderly women with urinary incontinence. An interview was used to evaluate the ability to stop the urinary stream during micturition and to calculate the incontinence index. A pad test was applied to objectively evaluate the severity of the disease. Functional testing included a digital examination to measure the force and duration of one contraction, a perineometer measurement (Peritron) to assess maximal contraction force and contraction force of 5 s, and a cone-retention test (Femcon) while walking for 1 min and during Valsalva's manoeuvre. This procedure was performed on three separate occasions within one week. The 37 participating women with a mean age of 62+/-8 (mean+/-SD) years had a severity index of 4.4+/-2.6 and a urine loss of 9.5+/-13.6 mg during the pad test. Sixteen women were able to completely stop the urinary stream during micturition. The digital examination showed no intratester variability. The perineometer measurement showed that the absolute difference in maximal contraction force and mean contraction force within 5 s was less than 5.3 mm Hg and 4.5 mm Hg, respectively, with a probability of 0.95. While walking and during Valsalva's manoeuvre, 19 and 20 women, respectively, held the same cone in place on all three occasions. The maximal contraction force and mean force during the 5-s contraction correlated well with the ability to stop the urinary stream and the digital examination but only weakly with the cone-retention tests. The reliability of PFM strength measurement is highest in the digital examination, followed by perineometer measurements, and then by vaginal cone tests. As PFM function is easy to assess, it should be routinely done in the assessment of urinary incontinence in elderly women.     

Assessment of voluntary pelvic floor muscle contraction in continent and incontinent women using transperineal ultrasound, manual muscle testing and vaginal squeeze pressure measurements

The aims of the study were: (1) to assess women performing voluntary pelvic floor muscle (PFM) contractions, on initial instruction without biofeedback teaching, using transperineal ultrasound, manual muscle testing, and perineometry and (2) to assess for associations between the different measurements of PFM function. Sixty continent (30 nulliparous and 30 parous) and 60 incontinent (30 stress urinary incontinence (SUI) and 30 urge urinary incontinence (UUI)) women were assessed. Bladder neck depression during attempts to perform an elevating pelvic floor muscle (PFM) contraction occurred in 17% of continent and 30% of incontinent women. The UUI group had the highest proportion of women who depressed the bladder neck (40%), although this was not statistically significant (p=0.060). The continent women were stronger on manual muscle testing (p=0.001) and perineometry (p=0.019) and had greater PFM endurance (p<0.001) than the incontinent women. There was a strong tendency for the continent women to have a greater degree of bladder neck elevation than the incontinent women (p=0.051). There was a moderate correlation between bladder neck movement during PFM contraction measured by ultrasound and PFM strength assessed by manual muscle testing (r=0.58, p=0.01) and perineometry (r=0.43, p=0.01). The observation that many women were performing PFM exercises incorrectly reinforces the need for individual PFM assessment with a skilled practitioner. The significant correlation between the measurements of bladder neck elevation during PFM contraction and PFM strength measured using MMT and perineometry supports the use of ultrasound in the assessment of PFM function; however, the correlation was only moderate and, therefore, indicates that the different measurement tools assess different aspects of PFM function. It is recommended that physiotherapists use a combination of assessment tools to evaluate the different aspects of PFM function that are important for continence. Ultrasound is useful to determine the direction of pelvic floor movement in the clinical assessment of pelvic floor muscle function in a mixed subject population.     

Evaluation of Pelvic Floor Muscle Strength Using Four Different Techniques

The aim of the study was to evaluate whether four different techniques were able to correctly measure pelvic floor muscle strength only. Sixteen volunteers performed a set of muscle contractions using the pelvic floor muscles (PFM) only, the abdominal muscles with and without PFM, gluteal muscles with and without PFM, adductor muscles with and without PFM and Valsalva maneuver with and without PFM. Pelvic floor muscle strength was evaluated by digital palpation, intravaginal EMG, pressure perineometry and perineal ultrasound. A “non-pelvic muscle induced” reading was defined as a significant increase even though the pelvic floor muscles were not contracted. Results were as follows: isolated abdominal muscle contraction: non-pelvic muscle induced readings in 3/8 women with EMG and in 3/8 with pressure perineometry; isolated gluteal muscle contraction: non-pelvic muscle induced readings in 1/2 women with EMG perineometry; isolated adductor muscle contraction: non-pelvic muscle induced readings in 6/11 women with EMG perineometry and in 2/11 women with pressure perineometry; Valsalva maneuver: non-pelvic muscle induced readings in 4/9 women with EMG perineometry and 9/9 women with pressure perineometry. It was concluded that EMG and pressure perineometry do not selectively depict pelvic floor muscle activity.     

Relationship between abdominal and pelvic floor muscle activation and intravaginal pressure during pelvic floor muscle contractions in healthy continent women

AIM: Activation of the abdominal muscles might contribute to the generation of a strong pelvic floor muscle contraction, and consequently may contribute to the continence mechanism in women. The purpose of this study was to determine the abdominal muscle activation levels and the patterns of muscle activity associated with voluntary pelvic floor muscle (PFM) contractions in urinary continent women. METHODS: Fifteen healthy continent women participated. They performed three maximal contractions of each of the four abdominal muscles and of their PFMs while in supine. Abdominal and PFM activity was recorded using electromyography (EMG), and intravaginal pressure was recorded using a custom modified Femiscan probe. RESULTS: During voluntary maximal PFM contractions, rectus abdominus was activated to 9.61 (+/-7.42)% maximal voluntary electrical activity (MVE), transversus abdominus was activated to 224.30(+/-47.4)% MVE, the external obliques were activated to 18.72(+/-13.33)% MVE, and the internal obliques were activated to 81.47(+/-63.57)% MVE. A clear pattern of activation emerged, whereby the transversus abdominus, internal oblique, and rectus abdominus muscles worked with the PFM in the initial generation of maximal intravaginal pressure. PFM activity predominated in the initial rise in lower vaginal pressure, with later increases in pressure (up to 70% maximum pressure) being associated with the combined activation of the PFM, rectus abdominus, internal obliques, and transverses abdominus. These abdominal muscles were the primary source of intravaginal pressure increases in the latter 30% of the task, whereas there was little increase in PFM activation from this point on. The external oblique muscles showed no clear pattern of activity, but worked at approximately 20% MVE throughout the PFM contractions, suggesting that their role may be predominantly in postural setting prior to the initiation of intravaginal pressure increases. CONCLUSIONS: Defined patterns of abdominal muscle activity were found in response to voluntary PFM contractions in healthy continent women.     

Clinical evaluation of pelvic floor muscle function in continent and incontinent women

AIMS: The aim of the study was to investigate the reliability of a scoring system for the investigation of voluntary and reflex co-contractions of abdominal and pelvic floor muscles in lying, sitting, and standing positions in continent and incontinent women. METHODS: A visual inspection and digital (strength, tone, speed, and endurance) palpation scale was developed to measure the coordination of the lower abdominal and pelvic floor muscles. Inter-observer reliability of the scales was investigated in 40 continent and 40 incontinent women. Differences between the continent and incontinent group were analysed. RESULTS: Inter-observer reliability for the visual inspection scale showed kappa values between 0.91 and 1.00, for tone percentage of agreement ranged from 95 to 100% (superficial) and 95 to 98% (deep muscle). Weighted Kappa (K(w)) varied from 0.77 to 0.95 for strength and 0.75 to 0.98 for the inward movement of superficial and deep pelvic floor muscles. K(w) for coordination between the superficial and deep part of the pelvic floor muscles groups was from 0.87 to 0.88 and 0.97 to 1.00 for endurance and global speed of the pelvic floor contraction. The continent women exhibited significantly better coordination between the pelvic floor and lower abdominal muscles during coughing in all three positions. Also the superficial part of the inward movement, the feeling and the coordination of the pelvic floor muscles were significantly better in the continent group. CONCLUSIONS: Visual inspection and digital tests are easy and reliable methods by which insight can be gained into the multi-muscular activity and coordination of the pelvic floor and lower abdominal muscles in continent and incontinent women.     

Assessment of pelvic floor movement using transabdominal and transperineal ultrasound

The aims of the study were (1) to assess the reliability of transabdominal (TA) and transperineal (TP) ultrasound during a pelvic floor muscle (PFM) contraction and Valsalva manoeuvre and (2) to compare TA ultrasound with TP ultrasound for predicting the direction and magnitude of bladder neck movement in a mixed subject population. A qualified sonographer assessed 120 women using both TA and TP ultrasound. Ten women were tested on two occasions for reliability. The reliability during PFM was excellent for both methods. TP ultrasound was more reliable than TA ultrasound during Valsalva. The percentage agreement between TA and TP ultrasound for assessing the direction of movement was 85% during PFM contraction, 100% during Valsalva. There were significant correlations between the magnitude of the measurements taken using TA and TP ultrasound and significant correlations with PFM strength assessed by digital palpation.