Physiotherapy as an Effective Method to Support the Treatment of Male Urinary Incontinence: A Systematic Review

Urinary incontinence (UI) is a serious health issue that affects both women and men. The risk of UI increases in men with age and after treatment for prostate cancer and affects up to 32% of men. Furthermore, UI may affect up to 69% of men after prostatectomy. Considering such a high incidence, it is critical to search for effective methods to mitigate this issue. Hence, the present review aims to provide an overview of physiotherapeutic methods and evaluate their effectiveness in treating UI in men. This systematic review was performed using articles included in PubMed, Embase, WoS, and PEDro databases. A total of 6965 relevant articles were found. However, after a risk of bias assessment, 39 studies met the inclusion criteria and were included in the review. The research showed that the available physiotherapeutic methods for treating men with UI, including those after prostatectomy, involve pelvic floor muscle training (PFMT) alone or in combination with biofeedback (BF) and/or electrostimulation (ES), vibrations, and traditional activity. In conclusion, PFMT is the gold standard of UI therapy, but it may be complemented by other techniques to provide a personalized treatment plan for patients. The effectiveness of the physiotherapeutic methods varies from study to study, and large methodological differences make it difficult to accurately compare individual results and draw unequivocal conclusions.


Introduction
Urinary incontinence (UI) affects up to 32% of men, although it presents more often in women [1,2]. A significant ailment affecting up to 69% of men is post-prostatectomy incontinence (PPI), following radical prostatectomy (RP), prostate irradiation, and surgery for benign prostatic hyperplasia [3]. However, as there is no precise definition of continence/incontinence, the number of men with UI may vary [4]. Prostate cancer is the most commonly diagnosed cancer in men [5]. RP generally bodes well in terms of oncological outcomes, but patients are still at risk of surgical and postoperative complications [6]. RP can damage the nerves and structures around the pelvic floor, leading to a weakened urethral sphincter and urethral bulb [7]. On the other hand, radiation therapy damages DNA, causing inflammation and structural changes in collagen [3]. UI affects quality of life and can intensify depression and anxiety [8]. Considering that pelvic floor physiotherapy is much less researched in men than in women, it is necessary to create guidelines and summarize possible physiotherapeutic solutions for the treatment of UI in men. The UI European Society of Urology (EAU) and American Association of Urology (AUA) guidelines recommend pelvic floor muscle therapy (PFMT) as first line treatment after prostatectomy [9]. These recommendations are very similar to the treatment of UI in women [10]. However, the anatomical differences of the pelvic floor between genders have to be taken into account. Most articles describing the main principles of PFMT are based on recommendations assuming female anatomy, which is undoubtedly a limitation for treating UI in men [11]. PFMT should be performed pre-operatively and immediately after catheter removal to optimize its effectiveness [12]. PFMT can be combined with biofeedback or electrostimulation. However, there are no specific recommendations as to the pelvic floor muscle training instructions, the number of repetitions, and optimal positions for exercises [13].
For this reason, the present study aims to review and identify physiotherapeutic methods in the treatment of men with UI, including those following prostatectomy, and to evaluate their effectiveness.

Materials and Methods
The review protocol was based on the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) [14] and registered in PROSPERO (protocol no. CRD42021278370). Inclusion criteria were based on the participant-intervention-comparatoroutcomes-study design (PICOS) format.
Participants: Only the following were considered: studies including men over 18 years of age, studies including men with UI or post-prostatectomy UI, and studies including both men and women, but where the results were separated by gender. Studies with men younger than 18 years of age or involving animal or in vitro models were excluded.
Intervention: Studies containing any physiotherapeutic intervention were included. Studies without intervention or where it was combined with pharmacotherapy and data analysis was not able to separate outcomes were also excluded.
Comparison: No intervention, relative to other methods, conservative treatment, and placebo.
Outcomes: Assessment of therapy effectiveness, UI symptoms, QoL, subjective assessment of health, urodynamic parameters, and quality of pelvic floor muscle contraction.
Study design: Randomized controlled trials, published in English or Polish. Nonexperimental studies and reviews were excluded.
The search was performed on 4 databases: PubMed, Embase, Web of Science, and PEDro. Articles in English and Polish up to 2022 were considered, and the lower limit of the publication date was not specified. The search was concluded on the fourth week of October 2022. Results from keyword searches were exported into Excel. Duplicates were then removed. Keywords were: (men) AND (urinary incontinence OR prostatectomy) AND (physiotherapy OR electrotherapy OR biofeedback OR pelvic floor muscle training OR magnetic stimulation OR conservative treatment OR physical therapy OR vibration OR rehabilitation).
Inclusion criteria were as follows: randomized controlled trials, studies involving adult men with UI, studies assessing the symptoms of PPI, studies assessing the effectiveness of physiotherapy, and manuscripts in English or Polish. Exclusion criteria included: studies other than RCTs, studies including women and where it was not possible to extract data by gender, studies without physical therapy, studies where QoL or UI symptoms were not measured, studies on people younger than 18 years of age, and studies in a language other than English or Polish.
The search was conducted independently by three researchers. The first screening of articles was evaluated by titles and abstracts against inclusion and exclusion criteria. After screening, full text articles were retrieved. Further inclusion depended on the type of study, detailed information about the participants, interventions, methods of evaluation and questionnaires used, and description of results and main conclusions. Finally, only RCTs were included, which were then assessed for the potential risk of bias. Any doubts and inconsistencies between the researchers were resolved by discussion or the inclusion of a fourth investigator.
Two researchers independently performed risk of bias analysis using the Risk of Bias 2 tool (Cochrane platform). Researchers evaluated 5 domains: randomization process, deviations from intended interventions, missing outcome data, outcome measurement, and selection of the reported result. Each domain consisted of questions that could be answered as follows: Yes/Probably Yes/Probably No/No/No Information. Based on the responses, each domain was rated as "low", "high", or "some concerns" regarding bias risk. All domains had to be rated as low risk for the study to be considered at a low risk of bias [15]. After the analysis was completed, researchers compared their answers. In cases of conflicting results, they either reached a solution or consulted with a third researcher. A detailed description of the risk of bias assessment can be found in Appendix A.

Results
The search identified 6965 records. After removing duplicates, 4220 studies remained. A total of 3973 studies were rejected after reviewing the titles and abstracts. A total of 247 papers remained to be fully read. After applying the inclusion and exclusion criteria, 193 works were disqualified. The remaining 55 papers were subjected to a risk of bias analysis. Based on the results of the RoB-2 risk of bias assessment tool, 33 studies were labeled as low risk, 6 as being of some concern, and 16 as high risk. Articles with a high risk of RoB were rejected. To increase the number of works describing physiotherapy in PPI, we decided to include works that were labelled with "some concerns" in the RoB-2 analysis. A total of 38 studies ultimately met all criteria. A detailed analysis of the review is presented in the PRISMA diagram ( Figure 1). Table 1 presents a brief description of the relevant studies. The RoB-2 risk of bias in every domain and the total percentage plot of the overall risk of bias are given in Appendix A.

Pelvic Floor Muscle Training in Men with UI
PFMT is the most basic, noninvasive conservative treatment of PPI [55]. The aim of pelvic floor muscle training (PFMT) in PPI is to improve continence by focusing on how PFM are involved in motion [11] as well as increasing strength, endurance, and the autonomic coordination of pelvic floor muscles and urethral sphincters [56]. PFMT contributes to better compression and an increase in pressure inside the urethra when there is a sudden increase in intra-abdominal pressure [57]. This highlights the need to integrate PFMT into daily activities that cause increased intra-abdominal pressure [11]. Standard PFMT usually consists of PFM exercises and the palpation of contractions with or without biofeedback (BF) [58]. However, the number of repetitions and their duration should be tailored to the patient. In order for PFMT to be effective, PFM exercises should be performed several times a day for several months [59]. In many studies, men were asked to focus on contracting in the anal sphincter area as if treating fecal incontinence [13], while PFMT after prostatectomy should focus on the urethra [11].
While PFMT performed before a prostatectomy can reduce the symptoms of UI after surgery, it is critical to continue therapy postoperatively [21,26]. Milios et al. [35] observed that the effectiveness of preoperative PFMT is influenced by the intensity of the exercises. Patients who participated in training sessions before the procedure and performed quick PFM contractions reported better continence improvement and QoL than men who underwent less intensive training [35]. Postoperative therapy should be started as soon as possible after removing the catheter [18,19,26,35] and continued until UI is resolved [19]. Perioperative physiotherapy effectively reduces problems with the urinary system compared to standard care [26]. The American Urological Association (AUA) recommends implementing PFMT before and 3 to 4 weeks after prostatectomy [60]. Regularly performing PFMT after prostatectomy reduces the need to use pads or other hygienic materials, which improves QoL and reduces social isolation [19]. Preoperative PFMT that was continued after surgery, compared to postoperative physiotherapy alone, is also better at minimizing UI in men with benign prostatic hyperplasia [18].
Most authors recommended that supervised training should be performed independently at home daily [19][20][21]23,26,29,32,37,42,46] and that supervised training is much more effective and long-lasting than unsupervised PFMT. In most studies, home PFMT consisted of three sets of 10 [37], 15 [43], or 20 PFM contractions in a single session [19]. Moore et al. [36] found that verbal and written instructions on PFMT and home exercises, combined with telephone call by nurse, is as beneficial as physiotherapy [36]. Heydenreich et al. [28] noted that unsupervised PFMT also improves UI; however, better outcomes were achieved with a physiotherapist session [28]. Overgard et al. [39] concluded that regular unsupervised PFMT reduces UI symptoms, but long-term effects were maintained when patients underwent physiotherapist-guided PFMT [39]. Apart from PFMT, physiotherapists can use supervised Pilates training [42] to diversify the exercises with appropriate accessories, e.g., an oscillating rod. Combining deep abdominal muscle and PFM activation increased the effectiveness of PFMT and reduced UI symptoms [28]. PFMT could be combined also with acupuncture [20]. A detailed description of the analyzed studies is presented in Table 2.  Men who underwent PMF re-education saw faster and better results in the reduction of UI symptoms after RP than in the placebo group. Manassero et al. (2007), Italy [32] Assessment of the influence of early, intense and long-term PMEs on the incidence of UI in men after bladder-sparing RRP surgery 107 men after RRP Con: 53 (aged 67.9 ± 5.5 yr) Exp: 54 (aged 66.8 ± 6.3 yr) Eventually, after 1 year, 54 men from Exp. and 40 men from Con. finished the trial.  The Pilates method is as effective as the standard PFMT. There were no statistically significant differences in the number of pads used between men from both intervention groups in the results of the 24 h PT and ICIQ-SF. Both intervention groups achieved greater improvement over Con. After 3 mth, no significant differences in UI were found between groups. However, after 12 mth, a significant improvement in urinary continence was observed in men who participated in sPFMT. Gr.1: PFMT + WBVT, 3× a wk for 4 wk: 1-2 session-frequency 20 Hz, peak to peak displacement of 2 mm, duration of each set of 45 s followed by 60 s rest; 3-12 session-a frequency of 40 Hz, peak-to-peak displacement of 4 mm, duration of each set of 60 s followed by 60 s rest.
Gr.2: PFMT. All men received the same guidelines for PFMT: PMEs daily, in 3 positions, 10 s of contraction, 10 s of relaxation, 15×; for slow twitch fibers, the time of contraction and relaxation was increased by 1 s every wk; fast twitch fibers-quick contractions and relaxation of PMF, 20×, then 10 s of rest-initially 2 sets, finally 4 sets. Assessment: I-VAS, ICIQ-SF, 24

Pelvic Floor Muscle Training and Biofeedback
A frequent early problem that limits the effectiveness of pelvic floor muscle exercises is the inability to properly contract and relax the correct muscle groups. Biofeedback is often utilized to help teach proper PFM activation [55]. The equipment used in BF provides visual and auditory feedback on PFM functionality, which is subsequently used to develop training parameters [61]. Visual information about PFM activity during exercise allows patients to correctly contract, increase body awareness, and motivate themselves to continue PFMT [55]. Verbal feedback from a therapist during the palpation of the levator ani muscle was also notably mentioned [24]. Floratos et al. [24] showed that the combination of PFMT with electromyography (EMG) and verbal feedback may have similar effectiveness in minimizing the symptoms of PPI [24]. Moore et al. [36] noted similar outcomes between physiotherapist-supervised PFMT, including BF and exercises performed at home following written instructions and supervised by a nurse via telemedicine [36].
Evaluating the effectiveness of PFMT combined with BF in the treatment of PPI was the aim of many articles [17,22,24,25,36,38,41,44,45,51]. Most authors conducted training with BF once a week [25,36,44,45,51], which lasted between 20 [51] and 30 min [17,24,25,44,45]. PFMT with BF is used in patients both before [17,22,41] and after radical prostatectomy [17,25,45,51]. Perez et al. [41] noted that preoperative PFMT with BF may be effective in reducing the symptoms of UI and erectile dysfunction as compared to no therapy after prostate removal [41]. However, there are studies that did not confirm these data [22]. Studies also differed in the number of sessions. This allowed us to note features such as two sessions of PFMT with BF [22] when compared to ten [41], which did not reduce the risk of developing UI. To improve urinary continence in men after prostatectomy, PFMT with BF should be continued after surgery [25,51]. Tienforti et al. [51] observed that a single preoperative PFMT session with BF and monthly postoperative sessions combined with home exercises effectively reduce the symptoms of PPI as compared to standard care and unsupervised exercise [51]. Oh et al. [38] noted that the BF device reduced UI symptoms compared to only verbal and written instructions, with differences being mainly visible after the first month of treatment [38]. However, this study was flagged as having some methodological concerns. In turn, Ribeiro et al. [45] showed that conducting early rehabilitation (PFTM with BF, 2 weeks after surgery) significantly improved continence, voiding symptoms, and pelvic floor muscle strength 12 months after surgery [45].
BF is a means of increasing a patient's awareness of their PFM, thus making PFMT more effective. However, if the patient remains unable to perform an isolated pelvic floor contraction, other techniques should be chosen to activate and restore PFM functionality. A detailed description of these studies is presented in Table 3.

Electrical Stimulation in Men with UI
The electrical stimulation (ES) of the pudendal nerve triggers the maximal contraction of the PFM, improves urethral pressure, and reduces detrusor overactivity [62]. Electrotherapy leads to passive PFM contraction, which is significant for patients with difficulties consciously contracting and relaxing their PFM [63]. Therefore, it is often used in UI therapy [62]. Electrical stimulation in male pelvic floor disorders is performed using surface electrodes, rectal electrodes, and transcutaneous electrical nerve stimulation. In men suffering from UI, electrostimulation is applied at the level of the spinal cord or nerves that control the lower urinary tract. The indirect electrotherapy of the pudendal nerve is believed to activate the PFM to then contract the urethra [64]. ES is, however, contraindicated when there is an oncological concern, as it may stimulate malignant cell proliferation [64].
ES is most often combined with PFMT in the treatment of UI [27,30,31,40,48]. It has been shown that transcutaneous and anal electrostimulation when combined with PMFT significantly reduces UI symptoms in men after RP [40]. Soto-Gonzales et al. [48] observed that the combination of BF with ES and PFMT home instruction significantly reduces UI symptoms and improves patients' quality of life. ES with PFMT also reduces erectile dysfunction [30]. PFMT effectiveness when combined with active and sham ES was also compared. Despite the observation that UI symptoms were lesser in men who received active ES months at 6 months, no similar differences were obtained after 12 months [52]. Laurienzo et al. [30] noted that regardless of whether patients received PFMT only at home or if PFMT included ES, continence improved as early as 3 months postoperatively [30].
It should be noted that the parameters of ES differ depending on the type of UI. In men with SUI, the frequency of 50 Hz is used; in patients with UUI, 4 Hz; and in patients suffering from mixed UI, therapy with both the above parameters can be used [27]. A detailed description of the analyzed studies is presented in Table 4.  After 6 months of the study, an improvement in the strength of PMF, a reduction in UI symptoms and erectile dysfunction in men from each group was shown. Nevertheless, no statistical differences were found between the groups.

Discussion
The purpose of this review was to determine what physiotherapeutic methods are used to treat PPI and assess their effectiveness. PPI can occur in 69% of men [65]; however, the true number may be different as there is no standardized definition of incontinence [4]. The most commonly assessed physiotherapeutic method in our review was PFMT, followed by ES and BF. Each of these techniques can help to improve continence after surgery.
Physiotherapy for men with prostate cancer should be performed before and after prostatectomy. PFMT before and after surgery is also important for patients with benign prostatic hyperplasia [18]. Studies showed the benefit of preoperative PFMT [21,35] to prepare the pelvic floor for postoperative physiotherapy. Centemero et al. [21] compared the effectiveness of pre-and postoperative training with only postoperative exercises. It has been shown that starting PFMT 30 days before the planned surgery and continuing it postoperative significantly minimizes the risk of UI and improves the QoL in men as compared to postoperative physiotherapy alone [21]. Similar outcomes were described by Milios et al. [35]. However, the study by Anan et al. [18] also showed that PFMT 28 days before and after the HoLEP procedure for BPH, compared to postoperative physiotherapy alone, minimizes the risk of UI, particularly at 3 months after the procedure.
Preoperative exercises increase neuromuscular reserves, teach the correct pattern of PFM contraction, increase muscle mass, and improve blood circulation in the pelvic floor area [55]. Despite the many benefits of preoperative PFMT, it only has a conditional level C recommendation (AUA) [60]. Preoperative PFMT can be combined with BF [22,25,41,51] and ES [30,52]. Preoperative PFMT combined with BF reduces the severity of UI after surgery and shortens the time needed until patients are able to control voiding [21]. Gezginci et al. [26] also noted that preoperative training, compared to standard care, improves both the continence and QoL of patients after RP.
The effectiveness of pre-and postoperative BF was also compared to postoperative BF alone [25]. One study found that combined pre-and postoperative training and postoperative training alone were similarly effective in minimizing UI symptoms [25]. The beneficial outcomes of preoperative BF compared to no physiotherapy were achieved after 10 training sessions consisting of maximal, fast, and slow PFM contractions [41]. However, similar results were not found by de Lira et al. [22]. The control group did not receive any physiotherapy, while only two supervised PFMT combined with BF were introduced before the surgery in the experimental group. PFMT was continued at home both before and after surgery [22]. Yamanishi et al. [52] combined preoperative PFMT with active and sham ES. Six months after surgery, significantly fewer UI symptoms were observed in men who received active ES. No similar differences were observed after 12 months. Men from both groups performed identical PFMT before and after surgery [52]. BF is more effective in reducing PPI symptoms than no treatment, while its preoperative efficacy should be more carefully investigated.
We, like numerous other studies, have observed the effectiveness of PFMT [6]. Verbal and written instructions, feedback about contractions, and performing PFM exercises at home (three series of fifteen repetitions) increase PFM strength, reduce UI symptoms, and improve QoL in men with prostate cancer after surgery as compared to no post-treatment physiotherapy [43]. A similar result was obtained by Manassero et al. [32]. Moreover, they showed that the benefits of regular PFMT in men persist one year after RP [32]. Faithfull et al. [23] observed a significantly greater improvement in UI symptoms after 3 months of physical therapy compared to standard care. Unfortunately, no similar differences were found after 6 months [23]. Three sets of exercises each lasting at least 3 min per day were also beneficial in the treatment of UI due to BPH [18]. PFMT has only a moderate evidence level B recommendation [60]. PFMT is recommended as a treatment for PPI in men according to the European Association of Urology, but there are no specific recommendations as to how it should be performed [66]. PFMT supervised by a physiotherapist may have better results in improving continence than training alone [37]. More research is required to determine the most effective PFM exercise plan [6].
PFMT is often combined with BF and ES. Van Kampen et al. [29] implemented anal ES in addition to PFMT in patients who could not activate PFM correctly or whose PFM strength was too low [29]. Bernardes et al. [20] combined PFMT with acupuncture in the treatment of UI after RP, noting that while PFMT alone is beneficial, patients who also used acupuncture had better results after 8 weeks. Pedriali et al. [42] showed that similar therapeutic effects after RP could be obtained both through Pilates training and standard PFMT in combination with ES [42]. Gomes et al. [27] noted that Pilates training or PFMT with ES significantly improved continence as compared to no postoperative rehabilitation [27]. If used in combination with PFMT, both transcutaneous perineal and anal electrostimulation have similar efficacy in the treatment of UI in men after RP [40]. The type of UI should first be determined to correctly select the therapy parameters [27,42]. In SUI, the most frequently used frequency is 50 Hz; in UUI, it is 4 Hz; and in MUI, both can be used [27,42]. ES can also be combined with BF [33]. The use of a 15-min BF followed by a 20-min ES beginning on the 7th day after decatheterization and continuing for 6 weeks eliminates the symptoms of UI in men after RP surgery. Combining ES with PFM can help patients who have difficulty in contracting PFM properly.
BF can also be combined with PFMT [16,19,21,35,41,46]. Studies have indicated that BF-assisted training can improve short-term and long-term continence more effectively than PFMT alone [67]. It has been observed that both verbal BF and combined EMG are beneficial after surgery [19]. The use of BF in the treatment of UI in men enables them to learn appropriate exercise patterns, improve motivation, improve QoL, and gain a sense of control in their therapy [68]. Nevertheless, the American Urological Association does not recommend adding BF to training [60].
Bladder training and supervised PFMT lasting at least 3 months is recommended as first-line therapy for people with UI. However, studies have shown that some of the therapies do not produce the desired effects or that results obtained with the same methods are contradictory [69].

Limitations of the Study
The current review has some limitations. The main one is the inclusion of only RCT studies, which reduced the total number of analyzed publications. Articles where it was impossible to isolate the results only for men were also rejected. We also wanted to compare how physiotherapy influenced UI treatment in men with prostate cancer. We therefore did not set any time limits for publication. Unfortunately, despite attempts to contact the authors of several articles, it was not possible to obtain full access to all publications. This issue affected mainly old publications.
RoB analysis was also performed to include the highest quality of studies, leading us to reject 16 articles. Notably, when compared to the meta-analyzes by Wang et al. [70] and Zhu et al. [71], we did not limited our work to just one physiotherapeutic method. We presented papers in which the therapy for men with UI was PFMT, BF, ES, and acupuncture, as well as their various combinations. Unfortunately, a further significant limitation when comparing the results was the variability of treatment regimens, differences in the measurement of treatment effects and different durations for follow-up. Similar problems were also reported by Kannan et al. [64]. Another important limitation when comparing the results was the lack of a clear definition of urinary incontinence in men, which may even distort the estimation of the scale of this problem [4].

Conclusions
In conclusion, according to the present review, physiotherapy is an important element in the fight against UI, especially following prostatectomy. The authors of this review demonstrated that PFMT, PFMT plus BFB and ES, and PFMT plus ES are effective approaches for reducing UI. This is a key element for preoperative preparation and personalized postoperative management. As it mainly focuses on improving the PFM function and innervation, the type and intensity of training and/or supplemental techniques should be selected individually depending on the patient's needs. Nevertheless, considering the small number of studies and inconsistent methodology behind assessing the effectiveness of therapy, it is necessary to conduct further invaluable research to optimize the physiotherapeutic approach for treating UI. Data Availability Statement: The data underlying this article will be shared on reasonable request to the corresponding author.

Conflicts of Interest:
The authors declare no conflict of interest.