Compararea eficacității antrenamentului mușchilor planșeului pelvian asistat de biofeedback și a exercițiilor hipopresive la femeile cu prolaps de organe pelviene: un studiu controlat randomizat

Introduction

Pelvic organ prolapse (POP) is a common condition in women, characterized by the displacement of pelvic organs towards the vagina⁽¹⁾. Various factors, such as aging, pregnancy, childbirth, structural weakness in connective tissue, obesity, chronic constipation, chronic cough, and prolonged exposure to conditions that increase intraabdominal pressure, such as heavy lifting, can lead to the weakening of pelvic floor muscles and the development of prolapse^(2,3). POP can result in a decline in quality of life due to various symptoms, including urinary incontinence/voiding difficulties, bowel evacuation difficulties, sexual dysfunction, pain and discomfort^(4,5).

Pelvic floor muscle training (PFMT) is one of the first-line treatments for managing POP symptoms. By increasing the strength of pelvic floor muscles, it enhances pelvic support and consequently helps reduce POP symptoms^(6,7). Studies have incorporated methods that require more active patient participation, such as biofeedback, to enhance the effectiveness of PFMT. In PFMT, biofeedback allows patients to monitor their pelvic floor muscle contractions through visual and auditory feedback, improving their understanding and engagement in the process, thereby increasing exercise effectiveness⁽⁸⁾.

Hypopressive exercises (HE) have gained popularity in recent years as an alternative exercise approach for the treatment of pelvic floor dysfunctions^(9,10). HE combines the activation of the transversus abdominis muscle with breathing techniques, aiming to reduce intraabdominal pressure, decrease the load on the pelvic floor muscles, and strengthen them. It has been suggested that HE are also effective in improving pelvic floor muscle function and may contribute to the reduction of prolapse symptoms by lowering intraabdominal pressure⁽¹¹⁾.

There are a limited number of studies examining the effectiveness of HE on POP and comparing it with PFMT. However, these studies have certain limitations due to factors such as patient population selection, treatment duration, and differences in treatment approaches. The majority of women lack sufficient knowledge about the pelvic floor and have limited access to accurate information regarding PFMT. Furthermore, the number of women practicing PFMT is quite low, and it remains unclear whether those who do perform the exercises are effectively engaging the correct muscles⁽¹²⁾. Given that properly learning PFMT itself is already challenging, understanding and correctly performing HE, which involves breathing techniques, may be even more difficult. In this context, the use of biofeedback in PFMT plays a crucial role in ensuring that patients learn the exercises correctly^(8,13). Therefore, the aim of this randomized controlled study was to compare the 12-week treatment effectiveness of biofeedback-assisted PFMT and HE, taught through a structured training process, with a control group in women with POP.

Materials and method

This study was designed as a prospective randomized controlled study. The research was approved by the university’s non-interventional ethics committee (Approval number: GO14/479-14). Written informed consent was obtained from all participants based on the Declaration of Helsinki.

Participants

Women aged 18 years and older who voluntarily agreed to participate and were diagnosed with stage 2 or stage 3 POP according to the Pelvic Organ Prolapse Quantification (POP-Q) system were included in the study. The exclusion criteria were defined as a history of neurological, rheumatological, psychiatric, or chronic diseases; pregnancy or postpartum period exceeding six months; receiving pelvic physiotherapy in the last six months; history of pelvic surgery; and inability to contract the pelvic floor muscles.

The participants who met the inclusion criteria were randomly assigned to three groups using a computer-based block randomization method (blocks of six): the PFMT group, the HE group, and the control group.

Interventions

In this study, after the initial assessments, the participants were randomly assigned to groups. All participants received information on the basic anatomy and physiology of the pelvic floor, its function, the definition of POP, and how it develops.

To ensure that participants performed the exercises correctly, they received three sessions of biofeedback-assisted PFMT/HE training. Subsequently, a physiotherapist with 10 years of experience in pelvic physiotherapy monitored the participants by scheduling follow-up sessions every 15 days over a total of 12 weeks. The participants were instructed to perform the prescribed exercises for 12 weeks and to mark their exercise log after each session to track their adherence.

Recommendations

All participants received lifestyle recommendations to help avoid risk factors that could trigger POP. They were advised to avoid heavy lifting, use proper body mechanics, maintain weight control, prevent constipation, and refrain from activities that strain the pelvic floor muscles (such as repeated straining or severe coughing)⁽¹⁴⁾.

Pelvic floor muscle training

The participants in the PFMT group received training on pelvic floor muscle awareness, contraction and relaxation using a vaginal probe biofeedback device (Myomed-632) while in the lithotomy position. The training included both visual and auditory cues to facilitate pelvic floor muscle activation, and PFMT exercises were taught accordingly. The biofeedback-assisted exercise training was completed in a total of three sessions, conducted every other day. The participants were instructed to perform the exercises at home. To ensure exercise adherence and maintain motivation, they were asked to complete an exercise log provided to them.

The participants followed a standardized PFMT program targeting both fast- and slow-twitch pelvic floor muscles. One set of exercises consisted of performing both slow and fast contractions 10 times each. In the first week, the participants were instructed to perform five sets of exercises daily. Over the first four weeks, the number of sets was gradually increased by five per week. From the fourth to the twelfth week, participants were required to maintain a daily routine of 20 sets. They were advised to perform the exercises in the most comfortable position (e.g., lying down, sitting, or standing)⁽¹⁵⁾.

Hypopressive exercises

The participants in the HE group were taught hypopressive exercises using a vaginal probe biofeedback device (Myomed-632) while in the lithotomy position. A similar approach to biofeedback-assisted PFMT training was used for teaching HE. The participants received biofeedback-assisted training in a total of three sessions conducted every other day. Afterward, they were instructed to perform the exercises at home and were given an exercise log to track their adherence.

During hypopressive exercises, the participants were instructed to inhale into their abdomen and expand it, then exhale while drawing their abdomen inward and simultaneously contracting their pelvic floor muscles gradually over 5 seconds. They were asked to hold the contraction at the peak for 5 seconds and then slowly relax over another 5 seconds while exhaling. Completing this sequence 10 times was considered one set. In the first week, participants were required to perform five sets of exercises daily. Over the first four weeks, the number of sets was gradually increased by five per week. From the fourth to the twelfth week, the participants were instructed to maintain a routine of 20 sets per day^(9,16). 

Assessments

The detailed demographic, physical and medical information of the participants screened for inclusion in the study was recorded. Assessments were conducted at baseline and at the end of the 12^th week.

Pelvic organ prolapse classification system

In the study, the severity of POP in participants was assessed using the POP-Q system. POP-Q is an objective and gold-standard classification method developed by the International Continence Society for POP assessment⁽¹⁷⁾. In the POP-Q assessment, specific reference points on the anterior-posterior vaginal wall, cervix, and perineal body were used. The evaluation was performed in the lithotomy position, both at rest and during maximal Valsalva maneuver. Six measurement reference points were utilized: Aa and Ba on the anterior vaginal wall, C and D in the superior compartment, and Ap and Bp on the posterior vaginal wall. Measurements were recorded in centimeters using the hymen as the reference point. Total vaginal length, genital hiatus length, and perineal body length were measured. Based on all these measurements, the stage of POP was determined⁽¹⁷⁾.

Pelvic Organ Prolapse Symptom Score

The Pelvic Organ Prolapse Symptom Score (POP-SS) is a seven-item scale developed in a five-point Likert format to assess the frequency of prolapse symptoms over the past four weeks⁽¹⁸⁾. The Turkish validity and reliability study was conducted by Ozengin et al. in 2017⁽¹⁹⁾. POP-SS was administered to participants before and after the 12-week treatment. POP-SS evaluates sensations such as the feeling of something coming out of the vagina, increased pain and discomfort in the vagina while standing, a sense of heaviness and pulling in the lower abdomen and lumbar region, the need to strain to empty the bladder, and the feeling of incomplete emptying after urination and defecation. Each item is scored between “0: never” and “4: always”. The total score ranges from 0 to 28⁽¹⁸⁾.

Pelvic Floor Distress Inventory

The Pelvic Floor Distress Inventory-20 (PFDI-20) assesses the distress caused by symptoms associated with pelvic floor disorders, such as pelvic organ prolapse (POP), urinary incontinence, and anal incontinence. The scale consists of a total of 20 items, each scored between 0 (never) and 4 (always). The total score ranges from 0 to 80⁽²⁰⁾. The Turkish validity and reliability study was conducted by Toprak Celenay et al.⁽²¹⁾ PFDI-20 was administered to participants before and after the 12-week treatment.

Pelvic floor muscle strength

A physiotherapist with 10 years of experience assessed the participants’ ability to voluntarily contract and relax their pelvic floor muscles through vaginal palpation. During the assessment of pelvic floor muscle strength, the expected pelvic floor muscle contraction was explained to the patient. Pelvic floor muscle strength was evaluated vaginally using a perineometer probe. During the assessment, the participants were asked to contract their pelvic floor muscles at maximum intensity. The highest value displayed on the perineometer screen during contraction was recorded. This procedure was repeated three times with 30-second intervals, and the average of the three values was used in the analysis⁽²²⁾.

Quality of life

The impact of POP on participants’ quality of life was assessed before and after the 12-week treatment using a 10-cm visual analog scale (VAS). The participants were asked to indicate the extent to which POP symptoms affected their quality of life on the VAS, where “0: POP symptoms have no impact on my quality of life” and “10: POP symptoms make my quality of life unbearable”.

Exercise adherence

A 10-cm VAS was used to evaluate the participants’ adherence to the exercise program, with “0: I did not perform any exercises” and “10: I completed all exercises without any omissions”. The participants were asked to mark on the VAS to indicate the extent to which they adhered to their prescribed pelvic floor exercise program over the 12 weeks.

Statistical analysis

The data obtained at the end of the study were analyzed using the statistical software SPSS 26 (Statistical Package for Mac version 26.0, Chicago, USA). The normality of numerical data distribution was assessed using the Shapiro-Wilk test and visual methods. The data were found not to follow a normal distribution. Numerical data were presented as median and interquartile range, while categorical data were expressed as frequency and percentage.

The comparison of numerical variables before and after treatment among the three groups was performed using the Kruskal-Wallis test. When a significant difference was detected, pairwise comparisons were conducted using the Mann-Whitney U test with Bonferroni correction. Within-group pre- and post-treatment comparisons were analyzed using the Wilcoxon signed-rank test. The chi-square test was used to compare categorical variables between groups.

The statistical significance was set at ppost hoc power analysis based on the comparison of POPSS scores among the three groups yielded an effect size (Cohen’s f) of 0.72. With a total sample size of 32 participants, the study achieved a power of 94% (0.94) at a=0.05.

Results

A total of 32 participants included in the study had a mean age of 47.9±9.9 years old and a mean Body Mass Index of 26±4 kg/m². The participants were randomly assigned to the PFMT group (n=10), the HE group (n=12), or the control group (n=10) – Figure 1. The groups were similar in terms of demographic, physical and medical history characteristics (p>0.05) – Table 1.

When the baseline POPSS, PFDI-20, pelvic floor muscle strength, and quality of life values were compared between groups, no statistically significant differences were found (p>0.05) – Table 2.

In within-group comparisons of pre- and post-treatment assessment parameters, significant improvements were observed in the PFMT and HE groups in terms of POPSS, PFDI-20, pelvic floor muscle strength, and quality of life (p<0.05). In the control group, there were no significant differences between pre- and post-treatment values (p>0.05) – Table 3. POPSS scores significantly decreased post-treatment in both the PFMT and HE groups (p=0.004 and p=0.002, respectively). PFDI-20 scores were also significantly lower post-treatment in the PFMT and HE groups (p=0.005 and p=0.002, respectively). Pelvic floor muscle strength significantly increased in both the PFMT and HE groups after the treatment (p=0.005 and p=0.02, respectively). The quality of life significantly improved after the treatment in the PFMT and HE groups (p=0.005 and p=0.002, respectively).

When post-treatment assessment parameters were compared among groups, significant differences were found in POPSS (p=0.02), pelvic floor muscle strength (p=0.006), and quality of life (p=0.003) (p<0.05), while PFDI-20 values were close to the significance threshold (p=0.055).

In pairwise comparisons of POPSS, no significant difference was found between the PFMT and HE groups (p=0.674), while significant differences were observed between the HE and the control groups (p=0.011) and the PFMT and the control groups (p=0.004).

For pelvic floor muscle strength, no significant difference was found between the PFMT and HE groups (p=0.228), but significant differences were observed between the HE and the control groups (p=0.007) and the PFMT and the control groups (p=0.004).

Regarding the quality of life, no significant difference was found between the PFMT and HE groups (p=0.203), while significant differences were observed between the HE and control groups (p=0.007) and the PFMT and control groups (p=0.002).

There was no significant difference in exercise adherence between the PFMT and HE groups (p=0.187) – Table 4.

Discussion

This randomized controlled study was conducted to evaluate the effectiveness of biofeedback-assisted PFMT and HE in women with pelvic organ prolapse. At the end of the study, both exercise methods were found to be effective in reducing POP symptoms, increasing pelvic floor muscle strength, and improving quality of life. This randomized controlled study provides a significant contribution to the literature by incorporating biofeedback-assisted PFMT/HE training and ensuring that the exercises were applied using the same standardized protocol across groups.

Resende et al.⁽¹⁴⁾ reported that pelvic floor muscle training is more effective than HE in improving POP symptoms, pelvic floor muscle function, and quality of life. Similarly, it has been stated that adding hypopressive exercises to PFMT does not provide additional benefits⁽¹⁶⁾. Contrary to these studies, our study observed that both exercise groups experienced a reduction in POP symptoms, an increase in pelvic floor muscle strength, and an improvement in quality of life. Although no statistically significant difference was found between the exercise groups, greater numerical changes were observed in the HE group regarding pelvic floor muscle strength and quality of life assessment parameters. This may be due to hypopressive exercises potential to enhance respiratory-related postural control mechanisms more effectively by reducing intraabdominal pressure and its possible greater effectiveness in increasing pelvic floor muscle strength.

For exercises to be effective, patients must learn and perform them correctly. Studies have shown that the majority of women lack sufficient knowledge about pelvic floor muscle training and often use incorrect techniques during exercises, such as straining, engaging the adductors or abdominal muscles, or attempting to stop urine flow while on the toilet^(12,23-25). While learning and correctly performing isolated PFMT are already challenging for most patients, it is evident that HE, which incorporates breathing techniques, requires even more guidance due to its complexity⁽¹⁴⁾. A recent systematic review reported that hypopressive exercises require more technical skill compared to pelvic floor muscle training and that its effectiveness may decrease if performed incorrectly⁽²⁶⁾. In the present study, both exercise methods were taught with intravaginal biofeedback support, which is a crucial step in ensuring that patients engage the correct muscles effectively. In this context, utilizing biofeedback to teach both PFMT and HE can support patients in correctly learning these exercises.

The effectiveness of exercises depends not only on performing them correctly, but also on patients’ adherence to regular practice. The literature indicates that maintaining long-term adherence to pelvic floor muscle training can be challenging due to factors such as forgetfulness, difficulties in time management, and lack of motivation^(27,28). Similarly, concerns exist regarding patients’ ability to sustain HE in the long term due to the complexity of the learning process⁽²⁶⁾. In our study, no significant difference was found between the PFMT and HE groups in terms of exercise adherence. Adherence levels in both groups were moderate to high. This suggests that teaching the exercises with biofeedback may have contributed to increased adherence in both groups. Biofeedback may have helped guide patients in targeting the correct muscles, ensuring effective exercise performance, and, together with the exercise log, may have enhanced patients’ motivation to continue exercising⁽²⁹⁾. However, sustaining adherence in long-term treatments remains uncertain.

The literature reports that short-term adherence rates for PFMT range from 53.5% to 92%, while long-term adherence rates decline to between 38.1% and 80%^(30,31). Although the adherence levels among participants in our study were moderate to high, there is still potential for further improvement. Therefore, new methods that enhance adherence and motivation, such as technology-assisted applications (mobile apps, digital tracking systems) and behavior change strategies, are needed^(32,33).

This study has some limitations. Firstly, the exercises were not tailored to the individual needs of participants; instead, the same intensive exercise protocol was applied to all participants. The importance of individualized exercise programs is increasingly emphasized, and an intensive exercise regimen may not be sustainable for some individuals. However, in our study, the aim was to ensure homogeneity by maintaining similar exercise intensity across randomized study groups. With the support of biofeedback, proper learning of the exercises was ensured, and a gradual progression approach was implemented to facilitate participants’ adherence to the exercise program. No additional strategies to enhance exercise motivation and adherence, such as mobile applications, group education or group sessions, were employed. The literature suggests that such methods may be effective in improving long-term exercise adherence.

Conclusions

In this randomized controlled study, the effectiveness of biofeedback-assisted pelvic floor muscle training and hypopressive exercises in women with pelvic organ prolapse was examined. At the end of the study, both exercise approaches led to a reduction in POP symptoms, an increase in pelvic floor muscle strength, and an improvement in quality of life. Teaching the exercises with biofeedback may have contributed to the correct execution of exercises and to improved adherence. Further studies are needed to investigate the long-term effectiveness of individualized exercise approaches and to explore additional methods to enhance patients’ adherence.

Autor corespondent: Emine Baran, e-mail: eminekbaran@gmail.com

CONFLICT OF INTEREST: none declared.

FINANCIAL SUPPORT: none declared.

This work is permanently accessible online free of charge and published under the CC-BY.