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Erschienen in: Wiener klinische Wochenschrift 1/2022

Open Access 22.03.2021 | review article

The effect of biofeedback interventions on pain, overall symptoms, quality of life and physiological parameters in patients with pelvic pain

A systematic review

verfasst von: Dr. Barbara Wagner, Mag. Margarete Steiner, Dr. Dominikus Franz Xaver Huber, MBA MMSc Univ. Prof. Dr. Richard Crevenna

Erschienen in: Wiener klinische Wochenschrift | Sonderheft 1/2022

Summary

Background

Biofeedback is recognized as an effective additive method for treating certain phenotypes of chronic pelvic pain syndrome and is a therapeutic option in other pelvic pain conditions. This review aims to evaluate evidence from the literature with a focus on the effect of biofeedback on pain reduction, overall symptom relief, physiological parameters and quality of life.

Methods

A systematic literature search was conducted using the databases PubMed, MEDLINE, Embase, Cochrane Library and PEDro from inception to July 2020. Data were tabulated and a narrative synthesis was carried out, since data heterogeneity did not allow a meta-analysis. The PEDro scale and the McMaster Critical Review Form—Quantitative Studies were applied to assess risk of bias.

Results

Out of 651 studies, 37 quantitative studies of primary research evaluating pelvic pain conditions in male and female adults and children were included. They covered biofeedback interventions on anorectal disorders, chronic prostatitis, female chronic pelvic pain conditions, urologic phenotypes in children and adults and a single study on low back pain. For anorectal disorders, several landmark studies demonstrate the efficacy of biofeedback. For other subtypes of chronic pelvic pain conditions there is tentative evidence that biofeedback-assisted training has a positive effect on pain reduction, overall symptoms relief and quality of life. Certain factors have been identified that might be relevant in improving treatment success.

Conclusions

For certain indications, biofeedback has been confirmed to be an effective treatment. For other phenotypes, promising findings should be further investigated in robust and well-designed randomized controlled trials.
Hinweise

Publisher’s Note

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Introduction

Biofeedback therapy is an instrument-based learning process employing operant conditioning. Autonomic and neuromuscular activity is measured and visual, acoustic and verbal feedback is provided to promote the acquisition of self-control over physiological processes, which are otherwise outside awareness or under less voluntary control [1].
Pelvic pain is perceived in pelvis-related structures and organs of either men or women and may be acute or chronic. In terms of chronic pelvic pain (CPP), there is no generally accepted definition. It can be subdivided into conditions with well-defined classical pathology and those with no obvious pathology—the chronic pelvic pain syndromes (CPPS). The European Association of Urology (EAU) describes CPPS as the occurrence of CPP with no proven infection or other obvious local pathology accounting for the pain, continuous or recurrent for at least 6 months. It is often associated with symptoms suggestive of lower urinary tract, sexual, bowel, gynecological or pelvic floor dysfunction and with negative cognitive, behavioral, sexual or emotional consequences [2].
Chronic pelvic pain is a common pain condition with a worldwide prevalence of 2.1–26.6% for noncyclic pain in women [35] and 2.2–9.7% in men [6].
Up to 85% of women with CPP have dysfunction of the musculoskeletal system, including spasm of the levator ani muscle [7]. Myofascial pelvic pain is a major component of CPP which is not always properly identified by healthcare providers [8]. It may be a primary or contributing source of CPP [8]. Its hallmark diagnostic indicators are myofascial trigger points in the pelvic floor musculature that refer pain to adjacent sites [8]. They are thought to occur in response to acute and chronic physical or psychosocial stress or trauma [9].
The pathophysiology of CPP is not well understood. Treatment is therefore often unsatisfactory and limited to symptom relief [7]. Several nonsurgical strategies exist that include medical, psychological, cognitive, behavioral, complementary and physical therapy [5, 7, 10]. In the case of myofascial pelvic pain in particular, a multidisciplinary team of specialists [8] and a multimodal treatment strategy are warranted. In a large proportion of patients, treatment does not necessarily result in pain relief. CPP therefore carries a significant physical, mental, and social burden for patients and puts a heavy burden on healthcare systems worldwide. Increased medical attention to identify and test effective treatment strategies is warranted [5, 7, 10, 11].
Biofeedback seems to be a promising adjuvant tool in the cognitive-behavioral treatment of somatoform disorders because it aims to enhance control over the psychophysiological processes that may be involved in these conditions [1]. Biofeedback is also one of several effective physical therapy techniques used to treat myofascial pelvic pain [8]. The recent EAU guidelines 2019 on CPP state that biofeedback is the preferred treatment for chronic anal pain and can improve the outcome of myofascial therapy as an adjuvant to muscle exercises in patients with hypertonic pelvic floor dysfunction [2]. It is considered a treatment option in type III chronic prostatitis according to the National Institutes of Health (NIH) classification [10].
Previous systematic reviews have evaluated the evidence of physiotherapy interventions in general in the management of CPP [5, 12, 13]. One review focused on the effect of biofeedback on improving symptoms of pelvic floor dysfunction in 2008 [14]. The primary aim of our review was to evaluate the effect of biofeedback interventions on subjective outcome pain, overall symptom improvement and quality of life in patients with acute or chronic pelvic pain conditions. A secondary aim was to investigate whether biofeedback interventions improved physiological parameters indicative of pelvic floor muscle tone and/or general relaxation.

Methods

Protocol and registration

A systematic review of the existing scientific literature was conducted, based on the guidelines recommended by the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement [15]. The review protocol was registered (PROSPERO registration number: CRD42020201751).

Identification and selection of studies

The search included the electronic databases PubMed, Medline, Embase, PEDro and Cochrane Library. Trials with the keywords “pelvic pain AND biofeedback” were extracted and considered for inclusion. No filters were used. No restrictions were placed on the year of publication. A systematic literature search was independently performed by two researchers (BW, MS) and disagreements in selection were resolved through discussion. The process was supervised by an experienced senior researcher (RC).

Inclusion and exclusion criteria

Table 1 presents the inclusion and exclusion criteria regarding study design, participants, interventions and outcome evaluation. Any quantitative study type of primary research (with the exception of case studies/case series less than 10 participants) was included to present a comprehensive overview of the current literature. This approach goes along with previous reviews [5, 13] which stated that including randomized controlled trials (RCTs) only was not feasible in reviewing physiotherapy interventions in patients with CPP. We considered males and females of all ages with either acute or chronic pelvic pain conditions as listed in the EAU guidelines [2], including both specific disease-associated pelvic pain and pelvic pain syndromes. Interventions were judged eligible if biofeedback was administered as a sole intervention or significant component of a multimodal or multidisciplinary intervention (including mechanical or electrical devices), as multidisciplinary management of CPP is considered optimal [13].
Table 1
Inclusion and exclusion criteria
 
Inclusion criteria
Exclusion criteria
Study design, comparison
Any quantitative study type of primary research with exception of case studies/case series < 10 participants; retrospective studies are included
Reviews, cross-sectional studies, case reports/case series < 10 participants, conference papers and abstracts, book chapters, editorials
Control interventions may include treatment as usual, no treatment, surgery, medicinal treatment, physical therapy modalities or placebo treatment
Unconcluded studies, studies with missing outcome data
Studies that were published in languages other than English and German
Participants
People with chronic pelvic pain according to the guidelines on chronic pelvic pain [2] including constipation (conditions with overactive pelvic floor dysfunction)
Pelvic organ prolapse, fecal or urinary incontinence (hypotonic pelvic floor dysfunction)
People with acute pelvic pain
Males and females
Children, adolescents, adults
Interventions
Biofeedback as a sole intervention or as a significant component of a multimodal intervention
No BFB-assisted training performed/BFB was not a relevant component of the treatment
Clinical (in/outpatient) setting or home-based training
If only a subgroup of the study population received BFB: studies were excluded if the number of subjects in the BFB subgroup or the outcome results of this subgroup were not stated
Insufficiently documented BFB intervention: no information on the training extent (frequency, number of sessions or duration of a single session) or the mode of application
Outcome measures
Primary outcome:
– Pain intensity
– Overall symptom improvement
– Quality of life
Secondary outcome:
– Physiological parameters, indicative of pelvic floor muscle tone or general relaxation
BFB biofeedback

Data collection and analysis

For eligible papers, the following data were extracted: study characteristics (author and year of publication, country site, study design, sample sizes, drop-out rate, diagnoses investigated, author’s conclusions), patient characteristics (sample characteristics, mean duration of symptoms, sex, mean age), intervention characteristics (interventions administered, time points of follow-up, biofeedback devices, training extent, intervention setting, adverse events) (Tables 2, 3 and 4). Primary outcome parameters were pain, overall symptom improvement and quality of life. Secondarily, physiological parameters were assessed. When certain data were not given in the respective studies the information was stated as “not available”.
Table 2
Study characteristics
Study
Country
Study design (details: see Table 8)
n of IG receiving BFB (n of whole study participants)
Drop-outs at last f/u/excluded from analysis
Diagnose(s), symptoms:
Conclusions by authors of respective papers
Anorectal pain syndrome
Chiarioni et al. 2010 [16]
Italy
RCT (3 arm): 3 different interventions compared
52 (157)
n.a.
Levator ani syndrome (constipation excluded)
BFB is superior to EGS and levator ani massage in pain relief. Improvements maintained for 12 months. Only patients with tenderness on rectal examination benefit. Pathophysiology of levator ani syndrome pathophysiology is similar to dyssynergic defecation type constipation
Heah et al. 1997 [17]
Singapore
Non-RCT, single-group (prospective)
16 (16)
0/16 (post treatment); n.a. (later f/u)
Levator ani syndrome
Although BFB had a negligible effect on anorectal physiologic measurements, it was effective in pain relief, with no side effects
Ger et al. 1993 [18]
USA
Non-RCT, 3 arm, non-randomized (prospective)
14 (60)
22/60
Chronic intractable rectal pain ± coccygodynia ± constipation/dyschezia (n = 34/60)
BFB vs. EGS vs. epidural steroid caudal block: EGS and BFB had almost the same poor results (>50% were refractory); No significant differences in rates of success or failure after any of the 3 therapeutic options, regardless of whether the option was a primary, secondary, or tertiary choice. Associated historic factors or abnormalities in anorectal physiologic studies did not influence results
Gilliland et al. 1997a [19]
USA
Non-RCT (retrospective)
86 (86)
11/86
Chronic intractable rectal pain ± constipation (n = 30/86)
EMG-based BFB can produce alleviation of idiopathic rectal pain. Outcome was significantly improved in patients who completed the treatment schedule compared to those who self-discharged. Outcome was not influenced by patients’ ages, duration of symptoms or prior history of surgery and was not significantly related to the presence of paradoxical puborectalis contraction (EMG or defecography)
Grimaud et al. 1991 [20]
France
Non-RCT, single-group (prospective) + cross-sectional
12 (24) 12 healthy
0/12
Chronic idiopathic anal pain ± constipation (n = 9/12)
Chronic idiopathic anal pain is associated with abnormal anorectal manometric profiles (↑ anal canal resting pressure), probably resulting from a dysfunctioning of the striated external anal sphincter. BFB is an effective treatment for chronic idiopathic anal pain. Anorectal pain disappeared after a mean of 8 BFB sessions
Constipation, dyssynergic defecation
Chiarioni et al. 2006 [21]
Italy
RCT (2 arm: intervention vs. different intervention)
54 (109)
14/109 (10/54 in BFB group)
Normal transit constipation due to PFD (Rome II criteria)
5 × 30min BFB sessions are more effective than continuous polyethylene glycol in PF dyssynergia (major improvement in 80%), benefits last at least 2 years. BFB should become the treatment of choice PFD. Predictors of better response to BFB: sensation of incomplete or blocked evacuation, straining with bowel movements; predictors of poorer response: digital facilitation of defecation
Koutsomanis et al. 1994 [22]
Italy
Non-RCT, single-group (prospective)
54 (109)
10/30
Idiopathic constipation
~50% of patients were helped by 2–6 BFB sessions, improvement persisted for ≥ 6–12 months. Both types of PF incoordination (inability to relax on defecation and inability to strain effectively) improved. No clear correlation between change in transit rate and symptomatic outcome
Chiotakakou-Faliakou et al. 1998 [23]
UK
Non-RCT (retrospective)
30 (30)
0/100
Chronic idiopathic slow and normal transit constipation
BFB is an effective long-term treatment for the majority of patients with idiopathic constipation unresponsive to traditional treatment (>50% improved). Patients with slow/normal transit, males/females, with/without paradoxical PF contraction benefited equally. Anorectal testing did not predict outcome
Battaglia et al. 2004 [24]
UK
Non-RCT, single-group (prospective)
100 (100)
n.a.
Chronic constipation (Rome II criteria)
Patients with PFD are likely to have continued benefit from BFB, whereas its effects on slow-transit constipation seems to be maximal in short-term course. Anorectal manometric variables remained unchanged (apart from sensation threshold ↓ in PFD group, maximum rectal tolerable volume ↓ in slow-transit group)
Wang et al. 2003 [25]
Italy
Non-RCT, single-group (prospective)
24 (24)
n.a.
Chronic idiopathic constipation (Rome II criteria)
BFB has a long-term effect with no side effects for most patients (62.5%) with chronic idiopathic constipation unresponsive to traditional treatment. Patients with slow/normal transit, with/without paradoxical PF contraction benefited equally. The psychological status rather than anorectal test could predict outcome. The efficacy of the two modes of BFB was similar
Ba-Bai-Ke-Re et al. 2014 [26]
China
RCT (2 arm: 2 different interventions)
50 (50)
0/44
Chronic obstructive constipation (Rome III criteria)
Manometric BFB-guided PF exercise is superior to oral polyethylene glycol for obstructive defecation for improving overall symptoms, pain at defecation, quality of life
Roy et al. 2000 [27]
China
Non-RCT (retrospective)
44 (88)
n.a.
Chronic idiopathic constipation (no surgery: n = 25/78, hysterectomy and no change in bowel function: n = 27/78, hysterectomy subjectively led to constipation: n = 26/78)
The majority of patients complaining of constipation induced by hysterectomy subjectively respond to behavioral treatment, in a similar proportion to those with idiopathic constipation. Physiological testing did not predict outcome
Chiarioni et al. 2005 [28]
UK
Non-RCT, single group (prospective)
78 (78)
7/52
Chronic idiopathic constipation (PFD: n = 34/52, slow transit only: n = 12/52, 1–2 criteria for PFD: n = 6/52)
BFB is an effective treatment for PFD but not slow-transit constipation. Improvements were maintained at f/u 24 months. BFB eliminated dyssynergia in 91% and enabled 85% to defecate the balloon. Success was predicted by PFD, milder constipation, and less frequent abdominal pain at baseline
Zhu et al. 2011 [29]
Italy
Non-RCT single group, observational
41 (41)
5/41
Functional constipation with PFD (Rome III criteria)
Before treatment, 7 Short Form-36 subscales (except bodily pain) were significantly lower in people with PFD than in healthy individuals. After BFB, all subcategories except general health showed improvement surpassing pretreatment baseline values and equalling those for normal. The total Patient Assessment of Constipation Quality of Life Questionnaire score also dramatically improved as did all subscales
Gilliland et al. 1997b [30]
USA
Non-RCT (retrospective)
194 (194)
16/194
Chronic constipation ± concomitant rectal pain (n = 30/194)
Success rate of BFB for constipated patients is less than previously reported (35% complete success, 13% partial success). Success rate ↑ after ≥ 5 sessions and was significantly related to patient’s willingness to complete treatment and number of sessions attended. Neither patient age, sex, abnormalities in manometry nor duration of symptoms significantly affected outcome
Parker et al. 2019 [31]
Canada
Non-RCT (retrospective)
130 (130)
38/168
Chronic constipation + PFD (n = 53/130), without PFD (n = 3/130), fecal incontinence (n = 49/130), constipation + fecal incontinence (n = 22/130), rectal pain (n = 3/130)
In patients with chronic constipation due to PFD, overall response rate was 69.8%, only 45.3% had symptomatic improvement. These patients are less likely to have symptomatic response than those with fecal incontinence. 3 BFB sessions are insufficient to manage dyssynergic defecation
Male chronic pelvic pain syndrome, urological chronic pelvic pain syndrome
Clemens et al. 2000 [32]
Non-RCT, single group
19 (19)
3/19
Nonbacterial male CPPS [33] (NIH type IIIA prostatitis: n = 6/19, NIH type IIIB prostatitis: n = 13/19)
A formalized program of neuromuscular reeducation of PF muscles with interval bladder training can provide significant, durable improvement in objective measures of pain, urgency, and frequency in patients with CPPS. Detrusor instability, hypersensitivity to filling, or bladder-sphincter pseudodyssynergia on pretreatment urodynamic studies were not predictive of treatment results
Cornel et al. 2005 [34]
USA
Non-RCT, single group; observational
33 (33)
2/33 (15/33 for EMG values)
Male CPPS (NIH type III prostatitis) [33]
BFB physical therapy and PF reeducation lead to a significant symptom improvement and decrease of PF muscle tonus
Yang et al. 2017 [35]
Netherlands
Non-RCT (retrospective)
22 (50)
5/50
Male CPPS (NIH type IIIA, IIIB prostatitis) [33]
Both electromagnetic stimulation and EGS + BFB physical therapy of PF muscle effectively reduce pain, increase quality of life and improve urinary tract symptoms in refractory male CPPS. EGS + BFB had additional benefits on pain and QoL compared to electromagnetic stimulation alone
He et al. 2010 [36]
Taiwan
Non-RCT (retrospective)
21 (21)
n.a.
Nonbacterial male CPPS + dysfunctional voiding
BFB had satisfactory short-term effects on patients with dysfunctional voiding and chronic prostatitis. Urodynamics could be used to help in the diagnosis and select the most appropriate treatment
Female chronic pelvic pain
Schmitt et al. 2017 [37]
USA
Non-RCT, single-group (prospective)
94 (94)
0/94 dropouts, but missing outcome data (n : Tables 2, 3 and 4)
Pelvic pain or dyspareunia (n = 29/94), defecatory smptoms (n = 31/94), urinary symptoms (n = 84/94)
An aggressive PF rehabilitation program including BFB with vaginal EGS had a high rate of self-reported subjective success and satisfaction in patients with PF dysfunction
Glazer et al. 1995 [38]
USA
Non-RCT, single-group (prospective)
33 (33)
n.a.
Vulvar vestibulitis syndrome
PF muscle instability is a critical factor in pain associated with vulvar vestibulitis syndrome. A BFB-assisted exercise program that stabilizes PF muscles significantly reduces and, in some cases, eliminates symptoms. The more the PF muscle stabilized, the more pain decreased, the higher the initial pain, the higher the pain reduction. 6‑month f/u indicated maintenance of therapeutic benefits
McKay et al. 2001 [39]
USA
Non-RCT, single-group (prospective)
29 (29)
Monthly f/u, 25/29 (!) after 11 months
Moderate—severe vulvar vestibulitis syndrome
EMG BFB of PF is an effective approach to vulvar vestibulitis. 88.9% reported negligible or mild pain after treatment
Gentilcore-Saulnier et al. 2010 [40]
Canada
Non-RCT, single-group (prospective) + cross-sectional
11 (22)
n.a.
Provoked vestibulodynia ± constipation, dysmenorrhea, urinary frequency
Women with provoked vestibulodynia showed altered PF muscle behavior compared to controls, providing empirical evidence of PF muscle dysfunction, especially at the superficial layer. A physiotherapy rehabilitation program targeting PF muscle dysfunction normalized PF muscle behavior
Bendana et al. 2009 [41]
USA
Non-RCT (retrospective)
52 (52)
0/52 dropoutsa
Painful PF spasm + urinary urgency/frequency
Combined transvaginal BFB, electrostimulation and behavioral therapy targeting PF relaxation demonstrated statistically significant improvement in urinary symptoms for up to 3 months. Further study for refractory patients is warranted
Philips et al. 1992 [42]
Canada
RCT (randomized yoked design, intervention vs. different vs. no intervention)
10 (30)
n.a.
Urethral syndrome + functional urinary incoordination (pelvic pain: n = 11/30, dyspareunia: n = 9/30)
Both EMG BFB and progressive muscle relaxation proved effective in improving symptomology and psychological state in patients with functional urinary incoordination
Hart et al. 1981 [43]
USA
Non-RCT, 2 arm: 2 different interventions (prospective)
14 (14)
3/14
Spasmodic dysmenorrhea according to MSQ
BFB and temperature training are effective in reducing many of the painful symptoms of primary dysmenorrhea. There was no significant difference between EMG and temperature training
Bennink et al. 1982 [44]
USA
RCT (3 arm: intervention ± different intervention vs. no intervention)
5 (15)
0/15
Primary dysmenorrhea (spasmodic or congestive)
Subjective reports indicated that the symptoms of dysmenorrhea improved for the BFB group but not for the relaxation or control groups
Vagedes et al. 2019 [45]
Germany
RCT (3 arm: 2 different interventions vs. standard care)
20 (60)
12/60 (6/20 in BFB group)
Primary dysmenorrhea
Preliminary evidence suggests that rhythmical massage might improve pain intensity after 12 weeks compared to usual care. No significant differences were found between heart rate variability-based home-BFB and the control group
Starr et al. 2013 [46]
USA
Non-RCT (retrospective)
778 (778)
97/778
PF dysfunction (urinary: n = 694/778, defecatory: n = 187/778, pelvic pain: n = 368/778)
Comprehensive PF rehabilitation including PF muscle training, BFB, EGS, constipation management, behavioral modification, incontinence devices, and pharmacotherapy is effective in treating women with PF dysfunction
Lúcio et al. 2014 [47]
Brazil
RCT, (3 arm: multimodal + sham vs. local vs. distal electrotherapy)
30 (30)
10/30
Woman with multiple sclerosis + sexual dysfunction
PF muscle training with EMG BFB—alone or combined with intravaginal EGS or transcutaneous tibial nerve stimulation—contributes to the improvement of sexual dysfunction in patients with multiple sclerosis
Aalaie et al. 2020 [48]
Iran
RCT (2 arm: 2 different interventions)
11 (22)
1/22 (in BFB group)
Female sexual pain dysfunction (DSM‑5 criteria [49, 50], FSFI) + stress urinary incontinence
Both BFB and EGS increased the FSFI score. Both interventions decreased pain during vaginal penetration similarly. To improve sexual function, women undergoing BFB seem to benefit more than those receiving EGS
Chronic pelvic pain in children
Hoebeke et al. 2004 [51]
Belgium
Non-RCT, single-group (prospective)
21 (21)
n.a.
PF spasms ± detrusor hyperactivity (n = 13/21), ±dysfunctional voiding (n = 5/21), ±constipation (n = 8/21)
Pelvic floor spasms in children (which can be secondary to detrusor overactivity) respond well to pelvic floor relaxation therapy
Ebiloglu et al. 2016 [52]
Turkey
Non-RCT (retrospective)
136 (136)
n.a.
Overactive bladder syndrome
BFB can be thought of as the first-line treatment option when standard urotherapy fails. Success rate was 53% for urgency, 69% for dysuria. The mean LUTSS significantly improved after BFB. Patients without holding maneuvers, daytime incontinence and enuresis had better recovery compared to the opposites
Ergin et al. 2016 [53]
Turkey
Non-RCT, single-group (prospective) + cross-sectional
52 (100) 48 healthy
13/52
Dysfunctional voiding (n = 52/100), +overactive bladder syndrome (n = 27/52)
Urinary nerve growth factor (UNGF) Ievels were higher in children with dysfunctional voiding and decreased after BFB. UNGF Ievels could be used for the diagnosis and the assessment of BFB success in these children
Li et al. 2006 [54]
China
Non-RCT, single-group (prospective) + cross-sectional
25 (40) 15 healthy
0/25
Pubertal chronic prostatitis, NIH type II (n = 1/25), IIIA (n = 3/25), IIIB (n = 21/25)
The main type of chronic prostatitis during puberty is IIIB; the dominating symptom is a voiding disorder. The impact on life and psychological effects are substantial. Pubertal boys with chronic prostatitis have PF dysfunction and several abnormal urodynamic values. The effect of BFB in pubertal chronic prostatitis is satisfactory
Musculoskeletal, low back pain, myofascial pain
Kent et al. 2015 [55]
Denmark
RCT (2 arm: intervention + standard care vs. placebo + standard care)
58 (112)
19/112
Subacute—chronic low back pain
Individualized movement retraining using motion-sensor biofeedback resulted in significant and sustained improvements in low back pain. This pilot trial also refined the procedures and sample size requirements for a fully powered RCT
BFB biofeedback, CPPS chronic pelvic pain syndrome, CP/CPPS chronic prostatitis/chronic pelvic pain syndrome, DSM-5 criteria diagnostic and statistical manual of mental disorders, EGS electrogalvanic stimulation, EMG electromyography, FSFI female sexual function index [56], f/u follow-up, IG intervention goup, LUTSS lower urinary tract symptom score [57], MSQ menstural Symptom questionnaire (MSQ) [58], NIH National Institute of Health, NIH-CPSI National Institute of Health – chronic prostatitis symptom index score, PF pelvic floor, PFD pelvic floor dyssynergia, ↓ significant decrease, ↑ significant increase, RCT randomized controlled trial, vs. versus
amissing outcome data: n = 31/52 for American Urological Association (AUA) symptom score [59], n = 39/52 for visual analog scale (VAS) [60]) symptom severity/effect daily life
Table 3
Patient characteristics
Study
Subgroups according to physiological testing (if applicable)
Mean symptom duration ± SD (range)
Sex %
Mean age IG in years ± SD (range)
Male
Female
Anorectal pain syndrome
Chiarioni et al. 2010 [16]
n.a.
17.1 ± 4.3 months (“high likely” LAS), 18.6 ± 4.8 (“possible” LAS)
19% (“high likely” LAS), 33% (“possible” LAS)b
48%
41.0 ± 10.0 in “high likely” LAS, 41.4 ± 10.3 in “possible” LASb
Heah et al. 1997 [17]
n.a.
32.5 ± 6.7 months
56.3%b
43.6%b
50.5 (39–66)
Ger et al. 1993 [18]
n.a.
54 (2–228) months
42.9%b
57.1%b
71 (n.a.)b
Gilliland et al. 1997a [19]
High resting pressures (manometry): n = 5/14, nonrelaxation or paradoxical PF contraction: n = 7/14, abnormal cinedefecography: n = 14/14
36 (3-lifelong) months
36.0%b
64.0%b
68 (12–96)b
Grimaud et al. 1991 [20]
n.a.
8 ± 6 (3–72) months
66.7%b
33.3%b
54 ± 3 (24–66)b
Constipation, dyssynergic defecation
Chiarioni et al. 2006 [21]
Slow transit constipation was excluded
>12 months
5.6%b
94.4b
33.3 ± 1.5b
Koutsomanis et al. 1994 [22]
Slow transit: n = 2/20, slow transit + pelvic incoordination: n = 11/20, pelvic incoordination: n = 7/20
n.a.
90.0%b
10.0%b
34 (18–53)b
Chiotakakou-Faliakou et al. 1998 [23]
Slow transit: n = 18/100, slow transit + paradoxcial PF contraction: n = 29/100, normal transit: n = 11/100, normal transit + paradoxical PF contraction: n = 15/100
n.a., median age of onset: 21 (0–70)
13.0%b
87.0%b
40 (10–79)b
Battaglia et al. 2004 [24]
PF dyssynergia, n = 14/24, slow transit: n = 10/24
>12 months
16.7%b
83.3%b
n.a., (27–54)b
Wang et al. 2003 [25]
Slow transit: n = 8/50, anorectic outlet obstruction: n = 36/50, both: n = 6/50
55.2 (30–360) months
28.0%b
72.0%b
52.6 (16–71)b
Ba-Bai-Ke-Re et al. 2014 [26]
n.a.
42 months
n.a.
n.a.
54 (n.a.)
Roy et al. 2000 [27]
Rectal prolapse: n = 12/78, rectocele: n = 22/78, slow transit: n = 53/78, paradoxical PF contraction: n = 40/78
Several years
0%b
100%b
n.a. (24–75)b
Chiarioni et al. 2005 [28]
n.a.
168 (24–480) months
05.8%b
94.2%b
34.9 ± 10.2 (23–63)b
Zhu et al. 2011 [29]
n.a.
n.a.
38.9%b
61.1%b
46.4 (21–65)b
Gilliland et al. 1997b [30]
Fixed or dynamic descent: n = 100/194, rectocele: n = 32/194, intussusception: n = 15/194
168 (2–lifelong) months
30.4%b
69.6%b
71 (11–96)b
Parker et al. 2019 [31]
Chronic constipation + dyssynergic defecation n = 53/130, without: n = 3/130
n.a.
20.8%b
79.2%b
57.5 ± 16.4b
Male chronic pelvic pain syndrome, urological chronic pelvic pain syndrome
Clemens et al. 2000 [32]
n.a.
n.a.
100%b
0%b
38 (18–67)b
Cornel et al. 2005 [34]
Detrusor instability: n = 5/19, diminished bladder capacity: n = 4/19, dysfunctional voiding of bladder (pseudodyssynergia): n = 6/19, cystometric abnormalities + pseudodyssynergia n = 3/19
≥3 months
100%b
0%b
45 (23–70)b
Yang et al. 2017 [35]
n.a.
30.4 (6–144) months
100%b
0%b
43.4 (24–68)b
He et al. 2010 [36]
n.a.
>3 months
100%b
0%
n.a.
Female chronic pelvic pain
Schmitt et al. 2017 [37]
n.a.
n.a.
0%
100%
52.2 ± 15.4 in n = 29 with pelvic pain
Glazer et al. 1995 [38]
n.a.
40.8 (24–72) months
0%
100%
31.5 (21–45)
McKay et al. 2001 [39]
n.a.
44.4 (24–60) months
0%
100%
35 (25–48)
Gentilcore-Saulnier et al. 2010 [40]
n.a.
48 ± 12 months
0%
100%
22 ± 2
Bendana et al. 2009 [41]
n.a.
n.a.
0%
100%
45.0 ± 17, (19–76)
Philips et al. 1992 [42]
n.a.
57 (4–240) months
0%b
100%b
25.7 ± 4.7b
Hart et al. 1981 [43]
n.a.
n.a.
0%
100%
26 ± 6.2
Bennink et al. 1982 [44]
n.a.
n.a.
0%a
100%a
19.2 (n.a.)a
Vagedes et al. 2019 [45]
n.a.
>1 year
0%a
100%a
29.7 ± 8.0a
Starr et al. 2013 [46]
n.a.
n.a.
0%b
100%b
51 (18–95)b
Lúcio et al. 2014 [47]
n.a.
4.1 (0.7–10) months
0%b
100%b
44.5 (36–51)b in intervention group 1
Aalaie et al. 2020 [48]
n.a.
n.a.
0%
100%
50.7 ± 6.1
Chronic pelvic pain in children
Hoebeke et al. 2004 [51]
n.a.
3 months
9.5%
90.5%
8.3 (n.a.)
Ebiloglu et al. 2016 [52]
Overactive bladder syndrome + dysfunctional voiding: n = 107/136, overactive bladder syndrome only: n = 29/136
n.a.
29.0%b
71.0%b
8.11 (5–14)b
Ergin et al. 2016 [53]
n.a.
n.a.
23.1%b
76.9%b
8.84 ± 2.54b
Li et al. 2006 [54]
n.a.
>3 months
100%b
0%
16.5 ± 1.1 (15–18)b
Musculoskeletal, low back pain, myofascial pain
Kent et al. 2015 [55]
n.a.
13 (4.25–13) months
48.0b
52.0%b
39 ± 12b
LAS levator ani syndrome, n.a. data not available, PF pelvic floor, IG intervention group, BFB biofeedback
aall study patients
bpatients in IG receiving BFB
Table 4
Intervention characteristics
Study
Interventions performed in longitudinal study arm
Time points of follow-up
BFB device details
BFB treatment details: number of sessions, duration per session (min/, frequency) (times/week), duration of whole intervention (weeks, if available)
Setting of BFB intervention (clinical/home-based), home exercise (=HE) encouraged (yes/not addressed)
Anorectal pain syndrome
Chiarioni et al.2010 [16]
IG 1: BFB + psychological counselling (5 sessions BFB + 4 sessions psychological counselling) (n = 52)
Baseline, 1, 3, 6, 12 months
Anal sEMG probe
5 sessions, 30 min, 1 ×/week
Clinical
IG 2: EGS (9 sessions, 30–45/min, 3 ×/week) + 4 sessions psychological counselling (n = 52)
Baseline, 1, 3, 6, 12 months
IG 3: massage of levator ani muscle (9 sessions, 30–45 min, 3 ×/week) + 4 sessions psychological counselling (n = 53)
Baseline, 1, 3, 6, 12 months
Heah et al. 1997 [17]
BFB
Baseline—2 weeks after treatment, mean f/u 12.8 ± 2.6 months
Anorectal manometry (rectal balloon)
4 sessions, 60 min, 1 ×/week
Clinical (HE: yes)
Ger et al. 1993 [18]
IG 1: EGS (3 sessions, 30–60 min, 7–10 days) (some had failed BFB, epitural caudal block earlier)
Baseline—mean f/u 15 [2–36] months after treatment
IG 2: BFB (50% had failed EGS earlier)
Same as IG1
Anal sEMG probe
≥6 sessions, 30–60 min, 1 ×/week
Clinical (HE: yes)
IG 3: epidural steroid caudal block (some had failed other modalities earlier)
Same as IG1
Gilliland et al. 1997a [19]
BFB including education, stress management and cognitive-behavioral psychotherapy techniques
Baseline—after treatment (time-points varied)
Anal sEMG probe
2–18 sessions (until improvement/persistent failure/self-discharge), 60 min; frequency n.a.
Clinical (HE: yes)
Grimaud et al. 1991 [20]
BFB + education
Baseline—after treatment, long term f/u after 16 ± 1 [10–24] months
Anorectal manometry
5–13 sessions, 30 min, 1 ×/week until pain disappearance (8 ± 1 [5–13] weeks), reeducation sessions over 6 months
Clinical (HE: yes)
Constipation, dyssynergic defecation
Chiarioni 2006 [21]
IG1: BFB
Baseline, 6, 12, 24 months after starting treatment
Anal sEMG probe
5 sessions, 30 min, 1 ×/week
Clinical, laxatives at home
IG2: laxatives (polyethylene glycol 1–2 packets daily + counselling with physician)
Same as IG1
Koutsomanis et al. 1994 [22]
BFB
Baseline, after treatment, 6 weeks after starting treatment, 6–12 months after 6‑week-f/u
sEMG skin electrodes close to anal verge (external anal sphincter), visual + acoustic feedback
Mean 4 [2–6] sessions (until improvement or persistent failure), 30–45 min, 1 ×/week
Clinical (HE: n.a.)
Chiotakakou-Faliakou et al. 1998 [23]
BFB + education, balloon defecation training
Baseline, after treatment, long term f/u (mean 23.4 [12–44]) months after treatment
sEMG skin electrodes close to anal verge (external anal sphincter), visual feedback
Mean 4 [1–10] sessions, duration n.a., 1 ×/1–2 weeks
Clinical (HE: yes)
Battaglia et al. 2004 [24]
BFB + balloon defecation training
Baseline, 3 months, 1 year after treatment
Anal sEMG plug
8 sessions, duration n.a., 2 ×/week, over 4 weeks
Clinical (HE: yes)
Wang et al. 2003 [25]
BFB: EMG vs. manometry based BFB
Baseline, after treatment, long term f/u (mean18 [12–28] months after treatment)
EMG based BFB: surface sEMG electrodes (anal sphincter), auditory + visual feedback; manometry based BFB: visual BFB
5 sessions, 30 min, 1 ×/week
Clinical (HE: yes)
Ba-Bai-Ke-Re et al. 2014 [26]
IG1: BFB
Baseline, 1, 3, 6 months after treatment
Anorectal manometry
4–5 sessions, duration n.a., 1/1–2 week
Clinical (HE: yes)
IG2: laxatives (polyethylene glycol, 17 g 3 ×/day, 2 weeks)
Roy et al. 2000 [27]
BFB
Baseline, after treatment, long-term f/u (mean 28 [12–44] months after treatment)
sEMG skin electrodes close to anal verge (external anal sphincter), visual feedback
4–5 sessions, duration n.a. 1/1–2 week
Clinical (HE: n.a.)
Chiarioni et al. 2005 [28]
BFB + balloon defecation training
Baseline, 1, 6, 12, 24 months after treatment
Anal sEMG plug, visual feedback
5 sessions, 30–45 min, 1 ×/week
Cinical (HE: n.a.)
Zhu et al. 2011 [29]
BFB
Baseline—after treatment (n.a.)
Water-perfused intra-anal instrument, visual + verbal feedback
6–10 sessions, 30–60 min, frequency n.a., over 4–8 weeks
Clinical (HE: yes)
Gilliland et al. 1997b [30]
BFB (+education, stress management, lifestyle modification)
Baseline—after treatment (n.a.)
Anal sEMG probe
2–>30 sessions (until symptom resolution/control over PF muscles in EMG/self-discharge: mean self-discharged: 5, finished: 11), 60 min, further data n.a
Clinical (HE: yes)
Parker et al. 2019 [31]
BFB (+education, exercise instructions, diet)
Baseline—after treatment (n.a.)
Anorectal manometry, visual feedback
Mean 2.9 [2–3] sessions, further data n.a.
Clinical (HE: yes)
Male chronic pelvic pain syndrome, Urological Chronic Pelvic Pain Syndrome
Clemens et al. 2000 [32]
BFB (PF reeducation + bladder training)
Baseline—mean 5.8 [1.6–14.8] months after treatment
sEMG electrodes
≤6 sessions, 60 min, 1 ×/2 week
Clinical (HE: yes)
Cornel et al. 2005 [34]
BFB
Baseline—after treatment (n.a.)
Anal sEMG probe
6–8 sessions, 1 ×/week, later 1 ×/2–4 weeks, duration n.a.
Clinical (HE: n.a.)
Yang et al. 2017 [35]
IG 1: EGS + BFB
Baseline—12 weeks after treatment
Anal sEMG probe
8 sessions, 45 min (15 min BFB, 30 min EGS), 1–2 ×/week, over 6 weeks
Clinical (HE: n.a.)
IG 2: electomagnetic stimulation (18 sessions, 30 min, 3 ×/week, 6 weeks)
Baseline—12 weeks after treatment
He et al. 2010 [36]
BFB
Baseline—10 weeks after treatment
Anal sEMG probe
No. sessions n.a., 30 min, 2–3 ×/week, over several weeks
Clinical (HE: n.a.)
Female chronic pelvic pain
Schmitt et al. 2017 [37]
BFB + vaginal EGS + behavioral modification + pharmacologic therapies for urinary and defecatory management
Baseline, after 1st, 3rd, final treatment session
sEMG skin electrodes (abdominals), vaginal/rectal sEMG probe
4–7 sessions (until ≥ 80% improvement), BFB + 30 min vaginal EGS, 1 ×/2 week
Clinical (HE: yes)
Glazer et al. 1995 [38]
BFB
Baseline, f/u at 6 clinical evaluation appointments + 6 months after 6th reevaluation
sEMG portable vaginal probe, visual feedback
20 min, 2 ×/day, 7 ×/week, after 6 evaluations: exercises continued without BFB ≥ 3 months
Home-based, 6 × clinical f/u
McKay et al. 2001 [39]
BFB
Baseline, f/u every 4 weeks
sEMG portable vaginal probe, visual feedback
No. sessions n.a., duration n.a., 60 repetitions, 2 ×/day, 7 ×/week, up to 11 months
Home-based, 1 ×/4 weeks clinical f/u
Gentilcore-Saulnier et al. 2010 [40]
BFB + education, manual therapy, EGS, dilator insertion
Baseline—after treatment (n.a.)
sEMG vaginal probe (deep PF), sEMG electrodes (superficial PF)
8 sessions, 60–75 min overall (10–15 min BFB), frequency n.a, over 12 ± 3 weeks
Clinical (HE: yes)
Bendana et al. 2009 [41]
BFB + education, vaginal EGS
Baseline, after treatment, 3 months after treatment
sEMG vaginal probe
6 sessions, 60 min (10 min BFB, 20 min EGS), 1 ×/week
Clinical (HE: n.a.)
Philips et al. 1992 [42]
IG1: BFB (±retention control/pain management techniques)
Baseline, after treatment, 2 months after treatment
Perivaginal sEMG electrodes, visual feedback
Mean 8 [5–12] sessions (until aim reached), further data n.a.
Clinical (HE: yes)
IG2: progressive muscle relaxation (±retention control/pain management), session number same as yoked partner in BFB group
Same as IG1
Comparison group: no intervention (cross-over after 2 months)
Same as IG1
Hart et al. 1981 [43]
IG 1: EMG general relaxation BFB
Baseline, after treatment (8 weeks), 8 weeks after treatment
sEMG electrodes frontalis muscle, aural feedback
Mean: 12.9 [9–15] sessions, 30 min, 2 ×/week, over 2 menstrual cycles
Clinical (HE: yes)
IG2: temperature general relaxation BFB
Same as IG1
Skin temperature, visual + aural feedback
Same as IG1
Same as IG1
Bennink et al. 1982 [44]
IG1: BFB + general relaxation
Baseline (interview), after first menstrual cycle (before treatment) and ~1 week after 3rd or 4th cycle (post treatment)
sEMG electrodes (lower abdomen), aural feedback
5 sessions, 30 min, 3 sessions before, 2 sessions on first 2 days of period
Clinical (HE: yes)
IG2: same general and PF relaxation training without BFB
Same as IG1
CG: no intervention
Same as IG1
Vagedes et al. 2019 [45]
IG1: BFB—slow breathing technique (general relaxation)
Baseline—after treatment (n.a.)
Heart rate variability Qiu (Biosign) device, visual feedback
15 min/day, 7 ×/week, over 12 weeks
Home-based, clinical f/u after 1, 3, then every 4 weeks
IG2: rhythmical massage (anthroposophic medicine) 30–45 min, 1 ×/week, 3 months
Same as IG1
CG: standard care (analgesics, physical exercise, warmth)
Same as IG1
Starr et al. 2013 [46]
Complex PF rehabilitation: instruction, behavioral management, EGS, BFB
2nd BFB treatment—after treatment
sEMG electrodes (abdominals), vaginal sEMG probe, anorectal manometry
5–8 sessions (8 if improvement < 80% after 5 sessions), 1 ×/2 weeks
Clinical (HE: yes)
Lúcio et al. 2014 [47]
IG1: BFB + PF muscle training + placebo EGS
Baseline—after treatment (12 weeks)
sEMG vaginal probe
24 sessions, 30 min, 2 ×/week, 12 weeks
Clinical (HE: yes)
IG2: BFB + PF muscle training + vaginal EGS (30 min, 2 ×/week, 12 weeks)
Same as IG1
Same as IG1
Same as IG1
Same as IG1
IG3: BFB + PF muscle training + transcutaneous tibial nerve stimulation (30 min, 2 ×/week, 12 weeks)
Same as IG1
Same as IG1
Same as IG1
Same as IG1
Aalaie et al. 2020 [48]
IG1: BFB, 100 min, 2 ×/week, 6 weeks + Kegel exercises at home
Baseline—2, 3 months after treatment
sEMG vaginal probe
12 sessions, 100 min, 2 ×/week, over 6 weeks
Clinical (HE: yes)
IG2: vaginal EGS (50 min of stimulation, 2 ×/week, 6 weeks) + Kegel exercises at home
Same as IG1
Chronic pelvic pain in children
Hoebeke et al. 2004 [51]
BFB ± anticholinergics (n = 13/21 with detrusor hyperactivity)
Baseline, after treatment (12 weeks)
Anal plug sEMG, visual BFB
12 sessions, duration n.a., 1 ×/week
Clinical (HE: n.a.)
Ebiloglu et al. 2016 [52]
BFB
Baseline, f/u at 3rd and 6th month (total treatment time: 6 months)
Uroflowmeter + sEMG perineal electrodes (external sphincter), visual feedback
4 sessions, 10 min, 1 ×/week (1st month), then continued without BFB, f/u BFB at 3rd, 6th month
Clinical (HE: yes)
Ergin et al. 2016 [53]
BFB
Baseline, after treatment (6 months)
Uroflowmetry including sEMG
≥6 sessions, over 6 months, further data n.a.
Clinical (HE: n.a.)
Li et al. 2006 [54]
BFB
Baseline, f/u after ~12 weeks
Urodynamic system: anal sEMG probe, abdominal pressure (intra-anal balloon catheter)
No. sessions n.a., 20–30 min, 2–3 ×/week, over several weeks
Clinical (HE: n.a.)
CG: healthy controls, no intervention
Musculoskeletal, low back pain, myofascial pain
Kent et al. 2015 [55]
IG-BFB: BFB based movement modification + education, guidelines-based medical or physiotherapy care
6 × during 10-weeks of treatment (baseline, week 1, 3, 6, 8, 10), f/u at week 12, 26, 52
Motion-sensor movement biofeedback (ViMove device), sEMG sensors, aural + vibrational feedback
6 (subacute pain)–8 (chronic pain) sessions, over 10 weeks, frequency n.a.
Clinical + home-based
IG-placebo: placebo + education, guidelines-based medical or physiotherapy care
Same as IG-BFB
BFB biofeedback, CG control group, EGS electrogalvanic stimulation, EMG electromyography, sEMG surface electromyography, HE home exercise, f/u follow-up, IG intervention group, min minute(s), PF pelvic floor
Outcome data were presented by means of the mean difference within a study group or between groups and their statistical significance (Tables 5, 6 and 7). Few studies provided effect sizes or the corresponding interval estimates (e.g. the confidence intervals) for the mean differences. These values were calculated by the authors if studies provided the relevant data to do so. The criteria for determining effect sizes according to Cohen [61] are listed in the legend of Tables 5 and 7.
Table 5
Primary outcome: effect on pain and overall symptoms
Study
n (total) (group 1, 2)
Group 1 (n1)
Group 2 (n2)
Outcome measure
Mean difference: Group 2 minus Group 1 [CI]
Effect size [strength]
P-value (for difference in means)
Anorectal pain syndrome
Chiarioni et al. 2010 [16]
104
IG1 (BFB) in pat. w LAS (52)
IG2 (EGS) in pat. w LAS (52)
SR: % pat. w adequate pain relief after 1 month
−26.9
n.a.
p<0.01f
104
IG1 (BFB) in pat. w LAS (52)
IG2 (EGS) in pat. w LAS (52)
SR: % pat. w adequate pain relief after 3 months
−18.9
n.a.
p<0.01f
104
IG1 (BFB) in pat. w LAS (52)
IG2 (EGS) in pat. w LAS (52)
SR: % pat. w adequate pain relief after 6 months
−31.2
n.a.
p<0.01f
104
IG1 (BFB) in pat. w LAS (52)
IG2 (EGS) in pat. w LAS (52)
SR: % pat. w adequate pain relief after 12 months
−31.2
n.a.
p<0.01f
105
IG1 (BFB) in pat. w LAS (52)
IG3 (massage) in patients with LAS (53)
SR: % pat. w adequate pain relief after 1 month
−31.3
n.a.
p<0.01f
105
IG1 (BFB) in pat. w LAS (52)
IG3 (massage) in patients with LAS (53)
SR: % pat. w adequate pain ↓ after 3, 6, 12 months
−36.9
n.a.
p<0.01f
104
BFB in pat. w “high likely” LAS (n.a.)
EGS in pat. w “high likely” LAS (n.a.)
SR: % pat. w adequate pain relief after 1, 3, 6, 12 months
In favour of BFB group
n.a.
p<0.025f
105
BFB in pat. w “high likely” LAS (n.a.)
Massage in pat. w “high likely” LAS (n.a.)
n.a.
p<0.025f
104
BFB in pat. w “possible” LAS (n.a.)
EGS in pat. w “possible” LAS (n.a.)
SR: % pat. w adequate pain relief after 1, 3, 6, 12 months
n.a.
p > 0.025f
105
BFB in pat. w “possible” LAS (n.a.)
Massage in pat. w “possible” LAS (n.a.)
n.a.
p > 0.025f
104
BFB in pat. w “high likely” LAS (n.a.)
EGS in pat. w “high likely” LAS (n.a.)
Subjective change in pain to baseline, ordinal scale [−2 to +3: −2 “a lot worse” to +3 “a lot better/cured”] after 1, 3, 6 months
In favour of BFB group
n.a.
p<0.025d
105
BFB in pat. w “high likely” LAS (n.a.)
Massage in pat. w “high likely” LAS (n.a.)
n.a.
p<0.025d
104
BFB in pat. w “possible” LAS (n.a.)
EGS in pat. w “possible” LAS (n.a.)
n.a.
p > 0.025d
105
BFB in pat. w “possible” LAS (n.a.)
Massage in pat. w “possible” LAS (n.a.)
n.a.
p > 0.025d
104
BFB in pat. w “high likely” LAS (n.a.)
EGS in pat. w “high likely” LAS (n.a.)
Number of days/months with rectal pain as stated in symptom log (0–30 days) after 1, 3, 6 months
In favour of BFB group
n.a.
p<0.025d
105
BFB in pat. w “high likely” LAS (n.a.)
Massage in pat. w “high likely” LAS (n.a.)
n.a.
p<0.025d
104
BFB in pat. w “possible” LAS (n.a.)
EGS in pat. w “possible” LAS (n.a.)
n.a.
p > 0.025d
105
BFB in pat. w “possible” LAS (n.a.)
Massage in pat. w “possible” LAS (n.a.)
n.a.
p > 0.025d
104
BFB in pat. w “high likely” LAS (n.a.)
EGS in pat. w “high likely” LAS (n.a.)
Pain: VAS (0–10 cm), average value of worst pain/wk, after 1, 3, 6 months
In favour of BFB group
n.a.
p<0.025d
105
BFB in pat. w “high likely” LAS (n.a.)
Massage in pat. w “high likely” LAS (n.a.)
n.a.
p<0.025d
104
BFB in pat. w “possible” LAS (n.a.)
EGS in pat. w “possible” LAS (n.a.)
n.a.
p > 0.025d
105
BFB in pat. w “possible” LAS (n.a.)
Massage in pat. w “possible” LAS (n.a.)
n.a.
p > 0.025d
Heah et al. 1997 [17]
16
Study group pre-BFB (16)
Study group post-BFB (16)
Pain VAS (0–10)
−6
n.a.
p<0.02
16
Study group pre-BFB (16)
Study group post-BFB (16)
SR: % pat. needing analgesics
−87.5
n.a.
p<0.03
Ger et al. 1993 [18]
14
n/a
IG2 (BFB group) post-BFB (14)
SR: % pat. w complete pain relief
14.3
n.a.
n.a.
14
n/a
IG2 (BFB group) post-BFB (14)
SR: % pat. w improved pain frequency/intensity
28.6
n.a.
n.a.
14
n/a
IG2 (BFB group) post-BFB (14)
SR: % pat. w no improvement
57.1
n.a.
n.a.
Gilliland et al. 1997a [19]
75
BFB in pat. w rectal pain only (47)
BFB in pat. with rectal pain and constipation (28)
SR: % patients reporting symptom improvement
−4.02
n.a.
p = 0.81
46
BFB subgroup of Group 1: pat. who finished trial (7)
BFB subgroup of Group 1: self-discharged early (39)
−57.5
n.a.
p<0.01
28
BFB subgroup of Group 2: pat. who finished trial (n.a.)
BFB subgroup of Group 2: self-discharged early (n.a.)
−46.7
n.a.
p<0.05
Constipation, dyssynergic defecation
Chiarioni et al. 2006 [21]
54
IG1 (BFB) pre-treatment (54)
IG1 (BFB) 6 months after starting treatment (54)
Frequency of abdominal pain/wk (symptom diary)
−0.69 [−0.74;−0.64]
−5.86 [H]
p<0.01c
54
IG1 (BFB) pre-treatment (54)
IG1 (BFB) 12 months after starting treatment (54)
−0.68 [−0.73; −0.63]
−5.78 [H]
p<0.01c
109
IG1 (BFB) 6 months after starting treatment (54)
IG2 (laxatives) 6 months after starting treatment (55)
0.63 [0.57;0.69]
4.85 [H]
p<0.01c
109
IG1 (BFB) 6 months after starting treatment (54)
IG2 (laxatives) 12 months after starting treatment (55)
0.58 [0.52;0.64]
4.26 [H]
p<0.01c
109
IG1 (BFB) 6 + 12 months after starting treatment (54)
IG2 (laxatives) 6 + 12 months after starting treatment (55)
SR: % patients reporting symptom improvement (4 out of a scale 0–4)
−57.8
n.a.
n.a.
54
n/a
IG1 (BFB) 6 + 12 months after starting treatment (54)
79.6
n.a.
n.a.
54
n/a
IG1 (BFB) 24 months after starting treatment (54)
81.5
n.a.
n.a.
Koutsomanis et al. 1994 [22]
20
Study group pre-BFB (20)
Study group immediately post-BFB (20)
SR: % patients reporting abdominal pain ≥ 1/week
−20
n.a.
≥0.05b
18
Study group pre-BFB (20)
Study group 6 weeks after starting BFB (18)
−13.3
n.a.
≥0.05b
20
Study group pre-BFB (20)
Study group 6–12 months after 6‑wk-f/u (20)
−10
n.a.
≥0.05b
20
Study group pre-BFB (20)
Study group immediately post-BFB (20)
Weekly total pain score (daily pain score: 0 = none, 3 = severe)
−5.5
n.a.
≥0.05b
18
Study group pre-BFB (20)
Study group 6 weeks after starting BFB (18)
−8
n.a.
p<0.01b
20
Study group pre-BFB (20)
Study group 6–12 months after 6‑wk-f/u (20)
−9
n.a.
p<0.01b
20
Study group pre-BFB (20)
Study group immediately post-BFB (20)
Weekly overall symptom score (daily score: 0 = better, 1 = same, 2 = worse)
−4
n.a.
p<0.01b
18
Study group pre-BFB (20)
Study group 6 weeks after starting BFB (18)
−4
n.a.
p<0.01b
20
Study group pre-BFB (20)
Study group 6–12 months after 6‑wk-f/u (20)
−6
n.a.
p<0.01b
Chiotakakou-Faliakou et al. 1998 [23]
100
Study group pre-BFB (100)
Study group post-BFB (100)
SR: % patients with abdominal pain
−16
n.a.
p=0.003f
100
Study group pre-BFB (100)
Study group long-term (mean 23.4 months) post-BFB (100)
−20
n.a.
p=0.0004f
100
n/a
Study group post-BFB (100)
SR: % patients stating BFB improved bowel symptoms (a little‑a lot)
66
n.a.
n.a.
100
n/a
Study group long-term (mean 23.4 months) post-BFB (100)
55
n.a.
n.a.
100
n/a
Study group post-BFB (100) in pat. w constipation
SR: % patients reporting sonstipation symptom improvement (a little‑a lot)
50
n.a.
n.a.
100
n/a
Study group long-term (23.4 months) post-BFB (100) in pat. w constipation
57
n.a.
n.a.
Battaglia et al. 2004 [24]
14
Subgroup with PF dyssynergia pre-BFB (14)
This subgroup 3 + 12 months after BFB (14)
SR: % patients with abdominal pain
−21.4
n.a.
n.a.
10
Subgroup with slow transit constipation pre-BFB (10)
This subgroup 3 months post-BFB (10)
−80
n.a.
n.a.
10
Subgroup with slow transit constipation pre-BFB (10)
This subgroup 12 months post-BFB (10)
−20
n.a.
n.a.
Wang et al. 2003 [25]
50
Study group pre-BFB (50)
Study group post-BFB (50)
SR: % patients with perianal pain at defacation
−28
n.a.
≥0.05a
50
Study group pre-BFB (50)
Study group 1‑year post-BFB (50)
−38
n.a.
≥0.05a
50
n/a
Study group post-BFB (50)
SR: % patients reporting overall symptom improvement
62
n.a.
n.a.
8
n/a
Pat. w slow transit constipation post-BFB (8)
37.5
n.a.
n.a.
36
n/a
Pat. w PF dysfunction post-BFB (36)
72.2
n.a.
n.a.
6
n/a
Pat. w combined PF dysf. +slow transit post-BFB (6)
33.3
n.a.
n.a.
Ba-Bai-Ke-Re et al. 2014 [26]
88
IG1 (BFB) 1 month post-treatment (44)
IG2 (laxatives) 1 month post-treatment (44)
SR; % of patients with peri-anal pain at defecation
36.4
n.a.
0.0006a
88
IG1 (BFB) 3 months post-treatment (44)
IG2 (laxatives) 3 months post-treatment (44)
20.5
n.a.
0.0534a
88
IG1 (BFB) 6 months post-treatment (44)
IG2 (laxatives) 6 months post-treatment (44)
20.5
n.a.
0.0375a
88
IG1 (BFB) 1 month post-treatment (44)
IG2 (laxatives) 1 month post-treatment (44)
Symptom score: Wexner constipation summary score (0–30 = worst) [62]
−6.00 [−7.41; −4.59]
−1.45 [VL]
p<0.001a
88
IG1 (BFB) 3 months post-treatment (44)
IG2 (laxatives) 3 months post-treatment (44)
−5.00 [−6.21;−3.78]
−1.40 [VL]
p<0.001a
88
IG1 (BFB) 6 months post-treatment (44)
IG2 (laxatives) 6 months post-treatment (44)
−6.00 [−7.11; −4.89]
−1.84 [VL]
p<0.001a
Roy et al. 2000 [27]
26
Pre-BFB in pat. w constipation, attributed to hysterectomy by patient (26)
Post-BFB in patients with constipation, attributed to hysterectomy by patient (26)
SR: % of patients with abdominal pain
−23.1
n.a.
n.a.
26
Pre-BFB in pat. w constipation, attributed to hysterectomy (26)
Long-term (28 months) post-BFB in patients with constipation, attributed to hysterectomy (26)
−11.5
n.a.
n.a.
27
Pre-BFB in pat. w constipation, not attributed to hysterectomy (27)
Post-BFB in pat. w constipation, not attributed to hysterectomy (27)
−29.6
n.a.
n.a.
27
Pre-BFB in pat. w constipation, not attributed to hysterectomy (27)
Long-term (28 months) post-BFB in pat. w constipation, not attributed to hysterectomy (27)
−29.6
n.a.
n.a.
25
Pre-BFB in pat. w constipation, no history of hysterectomy (25)
Post-BFB in pat. w constipation, no history of hysterectomy (25)
−28.0
n.a.
n.a.
25
Pre-BFB in pat. w constipation, no history of hysterectomy (25)
Long-term (28 months) post-BFB in pat. w constipation, no history of hysterectomy (25)
−36.0
n.a.
n.a.
78
Pre-BFB in all pat. w constipation (78)
Post-BFB in all pat. w constipation (78)
−27.0
n.a.
n.a.
78
Pre-BFB in all pat. w constipation (78)
Long-term (28 months) post-BFB in all pat. w constipation (78)
−25.6
n.a.
n.a.
78
n/a
28 months post-BFB in all pat. w constipation (78)
SR: % patients reporting constipation symptom improvement
61.5
n.a.
n.a.
Chiarioni et al. 2005 [28]
41
Subgroup with PF dysfunction after 1, 6, 12, 24 months after BFB (52, 50, 49, 45)
Subgroup with slow transit only, after 1, 6, 12, 24 months after BFB (52, 50, 49, 45)
Pain frequency (in favour of subgroup PF dyssynergia)
n.a.
n.a.
p<0.05a
Zhu et al. 2011 [29]
36
Study group pre-BFB (36)
Study group post-BFB (36)
SF-36 subscale pain (0–100: best)
10.3 [−1.31;21.91]
0.48 [S]
p=0.001a
36
Study group pre-BFB (36)
Study group post-BFB (36)
Symptom score (0–15 : 0 = none, 3 = severe for 5 symptoms)
−5.77 [−7.29;−4.25]
−2.04 [H]
p<0.001a
Gilliland et al. 1997b [30]
178
n/a
Study group post-BFB (178)
SR: % patients with ≥ 3 bowel movements/wk without aid (“complete success”)
35.0
n.a.
n.a.
178
n/a
Study group post-BFB (178)
SR: % patients with < 3 bowel movements/wk with reduced aid (“partial success”)
13.5
n.a.
n.a.
178
n/a
Study group post-BFB (178)
SR: % patients with no improvement (“failed”)
51.1
n.a.
n.a.
60
n/a
Study group post-BFB, pat. attended 2–4 sessions (60)
SR: % patients with ≥ 3 bowel movements/wk without aid (“complete success”)
18.0
n.a.
n.a.
118
n/a
Study group post-BFB, pat. attended ≥ 5 sessions (118)
44.0
n.a.
n.a.
178
n/a
Study group post-BFB, pat. attended 2–4 sessions (60)
−26.0
n.a.
p<0.001
52
n/a
Study group post-BFB, pat. completed BFB (52)
63.0
n.a.
n.a.
126
Study group post-BFB, pat. not completed BFB (126)
(25.0)
n.a.
n.a.
178
Study group post-BFB, pat. completed BFB (52)
Study group post-BFB, pat. not completed BFB (126)
−38.0
n.a.
n.a.
Parker et al. 2019 [31]
130
n/a
Whole study group post-BFB (130)
SR: % patients reporting symptom improvement (±improvement in anorectal manometry profile)
(55.4)
n.a.
n.a.
53
n/a
Subgroup with constipation + dys. defecation post-BFB (53)
(45.3)
n.a.
n.a.
3
n/a
Subgroup with rectal pain post-BFB (3)
(0.0)
n.a.
n.a.
Male chronic pelvic pain syndrome, Urological Chronic Pelvic Pain Syndrome
Clemens et al. 2000 [32]
16
Study group pre-BFB (19)
Study group 6 months post-BFB (16)
Pain VAS (0–9)
−4
n.a.
p=0.001b
16
Study group pre-BFB (19)
Study group 6 months post-BFB (16)
Symptom score: AUA [59]
−7.5
n.a.
p=0.001b
Cornel et al. 2005 [34]
31
Pstudy group re-BFB (33)
Study group post-BFB (31)
Symptom score: NIH-CPSI subdomain pain (0–21)
−5.3
n.a.
p=0.001b
31
Study group pre-BFB (33)
Study group post-BFB (31)
Symptom score: NIH-CPSI
−12.2
n.a.
p=0.001b
Yang et al. 2017 [35]
22
IG1 (BFB + EGS) pretreatment (24)
IG1 (BFB + EGS) 12 weeks post-treatment (22)
Pain VAS (0–10)
−3.5 [−4.91;−2.09]
−1.74 [VL]
p=0.001b
45
IG1 (BFB + EGS) 12 weeks post-treatment (22)
IG2 (PEMF) 12 weeks post-treatment (23)
0.6 [−1.44;0.24]
−0.34 [S]
p = 0.084a
22
IG1 (BFB + EGS) pretreatment (24)
IG1 (BFB + EGS) 12 weeks post-treatment (22)
NIH-CPSI subdomain pain (0–21)
−8.3 [−10.91;−5.70]
−2.23 [H]
p<0.001a
45
IG1 (BFB + EGS) 12 weeks post-treatment (22)
IG2 (PEMF) 12 weeks post-treatment (23)
0.1 [−1.98;1.78]
−0.03 [VS]
p = 0.035a
22
IG1 (BFB + EGS) pretreatment (24)
IG1 (BFB + EGS) 12 weeks post-treatment (22)
Symptom score: NIH-CPSI total score (0–43)
−14.3 [−19.82;−8.78]
−1.81 [VL]
p<0.001a
45
IG1 (BFB + EGS) 12 weeks post-treatment (22)
IG2 (PEMF) 12 weeks post-treatment (23)
0.5 [−3.98;2.98]
−0.07 [VS]
p=0.009a
22
IG1 (BFB + EGS) pretreatment (24)
IG1 (BFB + EGS) 12 weeks post-treatment (22)
Symptom score: IPPS
−4.6 [−8.64;−0.56]
−0.80 [M]
p=0.004a
45
IG1 (BFB + EGS) 12 weeks post-treatment (22)
IG2 (PEMF) 12 weeks post-treatment (23)
1.80 [−3.57;−0.03]
−0.49 [S]
p = 0.663a
He et al. 2010 [36]
21
Study group pre-BFB (21)
Study group 10 weeks post-BFB (21)
NIH-CPSI subdomain pain (0–21)
−1.80 [−3.13;−0.47]
−0.97 [L]
p<0.05b
21
Study group pre-BFB (21)
Study group 10 weeks post-BFB (21)
Symptom score: NIH-CPSI total score (0–43)
−13.3 [−16.7;−9.92]
−2.83 [H]
p<0.05b
Female chronic pelvic pain
Schmitt 2017 et al. [37]
26
Subgroup w pelvic pain/dyspareunia pre-treatment (29)
Subgroup w pelvic pain/dyspareunia after 3rd treatment (26)
Pelvic pain VAS (0–10)
−1
n.a.
p = 0.99b
27
Subgroup w pelvic pain/dyspareunia pre-treatment (29)
Subgroup w pelvic pain/dyspareunia after final treatment (27)
−3
n.a.
p = 0.27b
26
Subgroup w pelvic pain/dyspareunia after 3rd treatment (26)
Subgroup w pelvic pain/dyspareunia after final treatment (27)
−2
n.a.
p=0.02b
27
Subgroup w pelvic pain/dyspareunia after 3rd treatment (28)
Subgroup w pelvic pain/dyspareunia after final treatment (27)
Rating treatment success pelvic pain (0: none–10: very successful)
2
n.a.
p = 0.51b
14
Subgroup w pelvic pain/dyspareunia after 3rd treatment (14)
Subgroup w pelvic pain/dyspareunia after final treatment (16)
Rating treatment success dyspareunia (0: none–10: very successful)
3
n.a.
p = 0.20b
79
Subgroup w urinary symptoms after 3rd treatment (80)
Subgroup w urinary symptoms after final treatment (79)
Rating treatment success urinary symptoms (0: none–10: very successful)
2
n.a.
p<0.001b
15
Subgroup w defecatory symptoms after 3rd treatment (16)
Subgroup w defecatory symptoms after final treatment (15)
Rating treatment success defecatory symptoms (0: none–10: very successful)
1
n.a.
p = 0.003b
Glazer et al. 1995 [38]
33
Study group pre-BFB (33)
Study group after 6th clinical reevaluation with BFB (33)
Pelvic pain VAS (0–10)
−5.7
n.a.
p<0.001b
33
Study group pre-BFB (33)
Study group 6 months after 6th clinical reevaluation (33)
−6
n.a.
p<0.001b
33
Study group pre-BFB (33)
Study group after 6th clinical reevaluation + 6 months later (33)
SR: % of patients reporting intercrouse ≥ 1/month
66.67
n.a.
p<0.001b
McKay et al. 2001 [39]
11
Study group 1 month post-BFB (19)
Study group 6 months post BFB (11)
Pelvic pain VAS (0–10)
−6.8
n.a.
n.a.
11
Study group 1 month post-BFB (19)
Study group 6 months post BFB (11)
SR: % patients reporting intercourse
88.9
n.a.
n.a.
Gentilcore-Saulnier et al. 2010 [40]
11
IG pre-BFB in pat. with provoked vestibulodynia (11)
IG post-BFB in pat. w provoked vestibulodynia (11)
Pain NRS (0–10) during digital intravaginal assessment of superficial + deep PF
−2.00 [−3.33;−0.67]
−1.56 [VL]
p=0.007a
22
IG pre-BFB in pat. w provoked vestibulodynia (11)
Healthy CG without intervention (11)
−2.13 [−1.27;−2.99]
−1.73 [VL]
p=0.002a
22
IG post-BFB in pat. w provoked vestibulodynia (11)
Healthy CG without intervention (11)
−0.13 [−0.26;0.52]
0.23 [S]
p = 0.58a
11
IG pre-BFB in pat. w provoked vestibulodynia (11)
IG post-BFB in pat. w provoked vestibulodynia (11)
“unpleasantness” NRS (0–10) during manual assessment
−1.63 [−3.03;−023]
−1.21 [VL]
p=0.0009a
22
IG pre-BFB in pat. w provoked vestibulodynia (11)
Healthy CG without intervention (11)
−0.54 [−0.50;1.58]
0.36 [S]
p = 0.40a
22
IG post-BFB in pat. w provoked vestibulodynia (11)
Healthy CG without intervention (11)
−1.09 [−2.01;−0.17]
−0.83 [L]
p = 0.07a
11
IG pre-BFB in pat. w provoked vestibulodynia (11)
IG post-BFB in pat. w provoked vestibulodynia (11)
Painful pressure stimulus intensity levels (pressure to induce pain NRS 6/10, g/cm2)
92.00 [−162.25;346.25]
0.37 [S]
p = 0.07a
22
IG pre-BFB in pat. w provoked vestibulodynia (11)
Healthy CG without intervention (11)
201.00 [−366.64;−35.36]
−0.85 [L]
p=0.001a
22
IG post-BFB in pat. w provoked vestibulodynia (11)
Healthy CG without intervention (11)
109.00 [−246.63;28.63]
−0.56 [M]
p=0.03a
Bendana et al. 2009 [41]
21
Study group pre-BFB (52)
Study group 3 months post-BFB (21)
AUA symptom score—total score (0–35)
−7.97 [−12.25;−4.62]
−1.10 [L]
p<0.001a
21
Study group pre-BFB (52)
Study group 3 months post-BFB (21)
American Urological Association bother score (0–6)
−1.53 [−2.33; −0.87]
−1.13 [L]
p<0.001a
13
Study group pre-BFB (52)
Study group 3 months post-BFB (13)
VAS for symptom severity (1 = lowest 10 = most severe)
−2.44 [n.a.]
n.a.
p<0.001a
Philips et al. 1992 [42]
10
IG1 (BFB group) pre-BFB (10)
IG1 (BFB group) post-BFB (10)
Pain score: self-monitored
−1.30 [−29.40;26.80]
−0.05 [VS]
n.a.
10
IG1 (BFB group) pre-BFB (10)
IG1 (BFB group) 2 months post-BFB (10)
−11.40 [−26.55;3.75]
−0.82 [L]
n.a.
Hart et al. 1981 [43]
5
IG1: EMG BFB (5) baseline
IG1: EMG BFB (5) posttreatment
Symptom score: SSS total score: total of 15 symptoms (1 best −5 worst)
−7.00 [−11.85; −2.15]
−2.51 [H]
n.a.
5
IG1: EMG BFB (5) baseline
IG1: EMG BFB (5) 8 weeks posttreatment
−9.30 [−12.61; −6.00]
−4.89 [H]
n.a.
6
IG2: BFB skin temperature baseline (6)
IG2: BFB skin temperature posttreatment (6)
−2.00 [−8.86;4.86]
−0.44 [S]
n.a.
6
IG2: BFB skin temperature baseline (6)
IG2: BFB skin temperature 8 weeks posttreatment (6)
−8.10 [−14.25; −1.95]
−2.00 [H]
n.a.
Bennink et al. 1982 [44]
5
IG1 (relaxation + EMG BFB) pretreatment (5)
IG1 (relaxation + EMG BFB) posttreatment (5)
Symptom score: SSS total of 15 symptoms (1 best −5 worst)
−3.6 [−14.27;7.07]
−0.59 [M]
n.a.
5
IG1 (relaxation + EMG BFB) pretreatment (5)
IG1 (relaxation + EMG BFB) posttreatment (5)
SSS of subdomain cramps, backache, abdominal pain (1–5 = very severely)
−1.6 [−4.63;1.43]
−0.92 [L]
n.a.
5
IG1 (relaxation + EMG BFB) pretreatment (5)
IG1 (relaxation + EMG BFB) posttreatment (5)
SSS of subdomain cramps only (1–5 = very severely)
−0.6 [−1.47;0.27]
−1.19 [L]
n.a.
Vagedes et al. 2019 [45]
20
IG1 (BFB group) pre-BFB (20)
IG1 (BFB group) post-BFB (20)
Mean NRS (0–10) pain during menstruation
−0.3 [−1.2/0.6]g
−0.2 [VS]g
n.a.
37
IG1 (BFB group) postBFB (20)
No treatment CG (17)
0.9 [−2.10/0.30]g
−0.51 [M]g
p = 0.211
43
IG1 (BFB group) postBFB (20)
IG2 (rhythmical massage) post treatment (23)
−0.6 [−1.82/0.40]g
−0.34 [S]g
p = 0.361
20
IG1 (BFB group) pre-BFB (20)
IG1 (BFB group) post-BFB (20)
Maximum NRS (0–10) pain during menstruation
−0.5 [−1.4/0.3]g
−0.2 [S]g
n.a.
37
IG1 (BFB group) post-BFB (20)
No-treatment CG (17)
0.6 [−2.18/0.74]g
−0.40 [S]g
p > 0.05
43
IG1 (BFB group) post-BFB (20)
IG2 (rhythmical massage) post treatment (23)
−0.6 [−1.94/0.76]g
−0.23 [S]g
p > 0.05
Starr et al. 2013 [46]
694
Pre-BFB in pat. w urinary symptoms (694)
Post-BFB in pat. w urinary symptoms (n.a.)
% subjective global urinary symptom improvement since initial session (0: none–100%: perfect)
Mean 80–85% improvementh
n.a.
n.a.
187
Pre-BFB in pat. w bowl symptoms (187)
Post-BFB in pat. w bowl symptoms (n.a.)
% subjective global bowel symptom improvement since initial session (0: none–100%: perfect)
Mean 80–85% improvementh
n.a.
n.a.
368
Pre-BFB in pat. w pelvic pain symptoms (368)
Post-BFB in pat. w pelvic pain symptoms (n.a.)
% subjective global pelvic pain symptom improvement since the initial session (0: none–100%: perfect)
Mean 50–90% improve-menth
n.a.
p > 0.05
Lúcio et al. 2014 [47]
6
IG1 pre BFB, PFM training and sham-electro-stimulation (6)
IG1 post BFB, PFM training and sham electrostimulation (6)
Symptom score: FSFI subdomain pain
1.6
n.a.
p > 0.05b
6
IG1 pre BFB, PFM training and sham-electro-stimulation (6)
IG1 post BFB, PFM training and sham-electro-stimulation (6)
Symptom score: FSFI total score (2.0–36.0 = best)
−10
n.a.
p<0.05b
Aalaie et al. 2020 [48]
9
IG1 (BFB group) pre-treatment (10)
IG1 (BFB group) 3 months post-treatment (9)
Symptom score: FSFI subdomain pain
0.9 [0.1;1.6]g
η2 = 0.66 [L]g
p=0.026
20
IG1 (BFB group) 3 months post-treatment (9)
IG2 (EGS) 3 months post-treatment (11)
n.a.
η2 = 0.01 [S]g
p = 0.985
9
IG1 (BFB group) pre-treatment (10)
IG1 (BFB group) 3 months post-treatment (9)
Symptom score: FSFI total score (2.0–36.0 = best)
8.9 [7.0; 10.9]g
η2 = 0.96 [L]g
p<0.001
20
IG1 (BFB group) 3 months post-treatment (9)
IG2 (EGS) 3 months post-treatment (11)
n.a.
η2 = 0.64 [L]g
p=0.002
Chronic pelvic pain in children
Hoebeke et al. 2004 [51]
21
n/a
Study group post BFB (21)
SR: % patients reporting complete pain relief
80.95
n.a.
n.a.
21
n/a
Study group long-term f/u (16 months) (21)
66.67
n.a.
n.a.
Ebiloglu et al. 2016 [52]
136
Whole study group pre-BFB [136]
Whole study group post BFB (6 months) (136)
SR: % patients with dysuria
−19.85
n.a.
p=0.007c
107
Subgroup OBS and dysf. voiding pre-BFB (107)
Post BFB (6 months) in this subgroup (107)
−20.56
n.a.
p<0.001c
29
Subgroup OBS only pre-BFB (29)
Post BFB (6 months) in this subgroup (29)
−17.24
n.a.
p<0.001c
136
Whole study group pre-BFB (136)
Whole study group post BFB (6 months) (136)
Symptom score: LUTDSS
−8.2
n.a.
p<0.001c
Ergin et al. 2016 [53]
39
IG pat. w dysfunctional voiding pre-BFB in (52)
IG post BFB (6th month) (39)
SR: % patients with dysuria
−83.3
n.a.
p = 0.063c
39
IG pat. w dysfunctional voiding pre-BFB (52)
IG post BFB (6th month) (39)
Symptom score: DVISSS
−8.3
n.a.
p=0.019
Li et al. 2006 [54]
25
IG pat. w chronic prostatitis pre-BFB (25)
IG post BFB (after ~12 weeks) (25)
Symptom score: NIH-CPSI subdomain pain (0–21)
−2
n.a.
p=0.001b
25
IG pat. w chronic prostatitis pre-BFB (25)
IG post BFB (after ~12 weeks) (25)
Symptom score: NIH-CPSI total score (0–43)
−17
n.a.
p<0.001b
Musculoskeletal, low back pain, myofascial pain
Kent et al. 2015 [55]
58
IG pre-BFB (58)
IG 3 months post-BFB (58)
Pain VAS (0–10)
−20.5 [−30.45;−10.55]
−0.87 [VL]
n.a.
54
IG pre-Guidelines Care (54)
IG 3 months post-Guidelines care (54)
−6.5 [−9.34;−3.61]
−0.98 [VL]
n.a.
effect sizes are Cohen’s d if not marked otherwise; criteria for determining effect sizes for Cohen’s d calculated by the authors: [VS]: very small effect size, [S]: small effect size, [M]: medium effect size, [L]: large effect size, [VL] very large effect size, [H] huge effect size; criteria for determining effect sizes for Cohen’s d calculated by the authors: [VS]: dz 0.01–< 0.20, [S]: dz < 0.5, [M]: dz < 0.8, [L]: dz < 1.2, [VL]: dz < 2.0, [H]: dz ≥ 2.0 according to [61, 63]
AUA symptom score: Americal Urological Association Symptom Score [59]; BFB biofeedback; CG control group; CI confidence interval; DVISSS Dysfunctional Voiding and Incontinence Symptom Scoring System (DVISSS) [64]; EGS electrogalvanic stimulation; FSFI Female Sexual Function Index total score [56]; f/u follow-up; IG intervention group; IPPS International Prostate Symptom Score [65]; LAS levator ani syndrome; LUTDSS Lower Urinary Tract Dysfunction Symptom Score [57]; MD mean difference, n/a not applicable; n.a. not available; NIH-CPSI National Institutes of Health Chronic Prostatitis Symptom Index [66]; NMES neuromuscular electrical stimulation; NRS Numeric Rating Scale [60]; OBS overactive bladder syndrome; pat. patient; pat. w patients with; PEMF pulsed electromagnetic field therapy; PF pelvic floor; PFM pelvic floor muscle; QoL quality of life; SF-36 Short Form 36 [67]; SR success rate; SSS Symptom Severity Score [58]; UCPPS Urological Chronic Pelvic Pain Syndrome, VAS Visual Analog Scale [60]; w with
at‑test, bWilcoxon, cMcNemar, dANOVA, eANCOVA; fχ2, %: percent, geffect sizes and confidence intervals stated by authors of original studies (not marked: values calculated by review authors), hInconsistent charting in source data according to study authors
Table 6
Primary outcome: effect of biofeedback interventions on quality of life
Study
n (total group 1, 2)
Group 1 (n1)
Group 2 (n2)
Outcome measure
MD: group 2 minus group 1
95% CI lower bound
95% CI upper bound
Effect size [strength]
P-value (for difference in means)
Constipation, dyssynergic defecation
Ba-Bai-Ke-Re et al. 2014 [26]
88
IG1 (BFB) (44)
IG2 (laxatives) (44)
PAC-QoL 1 month post
12.00
10.904
13.096
3.731
H
p<0.001a
88
IG1 (BFB) (44)
IG2 (laxatives) (44)
PAC-QoL 3 months post
14.00
13.077
14.923
5.173
H
p<0.001a
88
IG1 (BFB) (44)
IG2 (laxatives) (44)
PAC-QoL 6 months post
16.00
15.299
16.701
7.784
H
p<0.001a
Zhu et al. 2011 [29]
36
Study group pre-BFB (36)
Study group post-BFB (36)
SF-36: physical functioning
7.30
−0.679
15.279
0.494
S
p=0.001a
36
Pre-BFB (36)
Post-BFB (36)
SF-36: role physical
23.80
2.347
45.253
0.599
M
p<0.001a
36
Pre-BFB (36)
Post-BFB (36)
SF-36: bodily pain
10.30
−1.301
21.901
0.479
S
p=0.001a
36
Pre-BFB (36)
Post-BFB (36)
SF-36: vitality
8.00
−3.932
19.932
0.362
S
p=0.042a
36
Pre-BFB (36)
Post-BFB (36)
SF-36: role emotional
19.50
0.387
38.613
0.551
M
p=0.001a
36
Pre-BFB (36)
Post-BFB (36)
SF-36: mental health
11.00
0.368
21.632
0.559
M
p=0.003a
36
Pre-BFB (36)
Post-BFB (36)
SF-36: social function
10.90
−0.701
22.510
0.507
M
p=0.014a
36
Pre-BFB (36)
Post-BFB (36)
SF-36: general health
10.50
−1.705
22.704
0.465
S
p=0.008a
36
Pre-BFB (36)
Post-BFB (36)
PAC-QOL: physical discomfort
−0.99
−1.561
−0.419
−0.937
L
p<0.001a
36
Pre-BFB (36)
Post-BFB (36)
PAC-QOL: psycho-social discomfort
−0.37
−0.784
0.044
−0.482
S
p<0.001a
36
Pre-BFB (36)
Post-BFB (36)
PAC-QOL: worries, concerns
−0.98
−1.420
−0.540
−1.201
VL
p<0.001a
36
Pre-BFB (36)
Post-BFB (36)
PAC-QOL: satisfaction
−1.33
−1.834
−0.826
−1.425
VL
p<0.001a
36
Pre-BFB (36)
Post-BFB (36)
PAC-QOL: overall
−0.92
−1.277
−0.563
−1.393
VL
p<0.001a
Male chronic pelvic pain syndrome, Urological Chronic Pelvic Pain Syndrome
Cornel et al. 2005 [34]
31
Study group pre-BFB (31)
Study group post-BFB (31)
NIH-CPSI: QoL (0–12 points)
−3.80
n.a.
n.a.
n.a.
n.a.
p<0.001b
Yang et al. 2017 [35]
22
IG1 (BFB + NMES) pretreatment (22)
IG1 12 weeks post-treatment (22)
NIH-CPSI: QoL
−5.20
−7.523
−2.870
−1.564
VL
p<0.001a
45
BFB + NMES (22)
PEMF (23)
NIH-CPSI: QoL 12 wks post
1.20
−0.382
2.782
0.365
S
p=0.012a
He et al. 2009 [36]
21
Study group pre-BFB (21)
Study group 10 weeks post-BFB (21)
NIH-CPSI: life impact
−6.70
−8.605
−4.795
−2.528
H
p<0.05b
Female chronic pelvic pain
Gentilcore-Saulnier et al. 2010 [40]
11
IG (provoked vestibulodynia) pre-BFB (11)
IG post-BFB (11)
Perceived impact on QoL (0 = no to 10 = worst)
−1.55
−3.367
0.267
−0.882
L
p=0.003a
Bendana et al. 2009 [41]
13
Strudy group pre-BFB (52)
Study group 3 months post-BFB (13)
VAS (0–10)
−2.56
n.a.
n.a.
n.a.
n.a.
p<0.001a
Vagedes et al. 2019 [45]
20
IG1 (BFB) pre-BFB (20)
IG1 post-BFB (20)
SF-12: mental score
4.1c
−0.3c
8.4c
0.4c
S
n.a.
20
IG1 (BFB) pre-BFB (20)
IG1 post-BFB (20)
SF-12: physical score
4.4c
0.4c
8.5c
0.5c
S
n.a.
20
IG1 (BFB) pre-BFB (20)
IG1 post-BFB (20)
SF-12: sum score
8.7c
3.5c
13.8c
0.6c
M
n.a.
37
IG1 (BFB) post-BFB (20)
CG (usual care) (17)
SF-12: sum score
6.13c
−3.09c
15.35c
0.41c
S
p > 0.05
43
IG1 (BFB) post-BFB (20)
IG2 (massage) post-treatment (23)
SF-12: sum score
−0.57c
−9.18c
8.03c
−0.04c
VS
p > 0.05
Chronic pelvic pain in children
Li et al. 2006 [54]
22
IG patients with chronic prostatitis post-BFB (25)
IG post-BFB (22)
NIH-CPSI: life impact
8
n.a.
n.a.
n.a.
n.a.
p<0.001b
effect size strength: [VS]: very small effect size, [S]: small effect size, [M]: medium effect size, [L]: large effect size, [VL] very large effect size, [H] huge effect size; criteria for determining effect sizes for Cohen’s d calculated by the authors (c): [VS]: dz 0.01–<0.20, [S]: dz < 0.5, [M]: dz < 0.8, [L]: dz < 1.2, [VL]: dz < 2.0, [H]: dz ≥ 2.0 according to [61, 63]; criteria for determining effect sizes not calculated by the authors are stated in the respective studies; effect sizes and confidence intervals which were calculated by the review authors are not marked, those effect sizes and confidence intervals that are stated in respective paper are marked with (c)
BFB biofeedback, CG control group, CI confidence interval, IG intervention group, MD mean difference, n.a. data not available, NIH-CPSI National Institutes of Health Chronic Prostatitis Symptom Index [66], NMES neuromuscular electrical stimulation, PEMF pulsed electromagnetic field therapy, QoL quality of life, SF-12 Short Form-12 [68], SF-36 Short Form 36 [67], UCPPS Urological Chronic Pelvic Pain Syndrome, VAS visual analog scale; wk/wks week(s)
at‑test, bWilcoxon
Table 7
Secondary outcome: Effect of biofeedback interventions on physiological parameters
Study
Secondarily evaluated outcome measure
Domain, subgroup
f/u
IG pre-post
IG vs. IG /IG vs. CG
Significant improvement in subdomains, significant difference between IG/IG or IG/CG (p-value)
No significant improvement in subdomains or no significant difference between IG/IG, IG/CG (p-value)
Anorectal pain syndrome
Chiarioni et al. 2010 [16]
Anorectal manometry
IG1 BFB group: patients with high likely LAS
Baseline–1 month
x
Anal pressure with straining (% relaxing), balloon defecation (% successful), urge threshold (ml), maximum tolerable volume (ml), compliance (mm Hg) (p < 0.025)
Resting anal canal pressure (mm Hg), rectoanal inhibitory reflex threshold (ml) (p ≥ 0.025)
Baseline–3 month
x
Anal pressure with straining (% relaxing), balloon defecation (% successful), rectoanal inhibitory reflex threshold (ml), urge threshold (ml), maximum tolerable volume (ml) (p < 0.025)
Resting anal canal pressure (mm Hg), compliance (mm Hg) (p ≥ 0.025)
IG1 BFB group: patients with possible LAS
Baseline—1 month, baseline—3 months
x
Anal pressure with straining (% relaxing), balloon defecation (% successful) (p < 0.025)
Resting anal canal pressure (mm Hg), rectoanal inhibitory reflex threshold (ml), urge threshold (ml), maximum tolerable volume (ml), compliance (mm Hg) (p < 0.025)
IG1 BFB group (n = 52) vs. IG2 EGS (n = 52) or IG3 massage group (n = 53) (in favour of BFB) in patients with high likely LAS
After 1 month, after 3 months
x
Anal pressure with straining (% relaxing), balloon defecation (% successful) (p < 0.025)
Resting anal canal pressure (mm Hg), rectoanal inhibitory reflex threshold (ml), urge threshold (ml), maximum tolerable volume (ml), compliance (mm Hg) (p < 0.025)
Heah et al. 1997 [17]
Anorectal manometry
Study group (n = 16)
Baseline—after treatment
x
None (p < 0.052)
Anal canal mean resting/maximum squeeze pressure (mm Hg), rectum volume first sensation (ml)/maximum tolerable volume (ml)/compliance (ml/mm Hg), perineal descent rest/strain (cm) (p > 0.05)
Grimaud et al. 1991 [20]
Anorectal manometry
Study group (n = 12)
Baseline—after treatment
x
Anal canal resting pressure (mm Hg), p < 0.01 (no significant difference any more compared to healthy controls without BFB intervention)
Constipation, dyssynergic defecation
Chiarioni et al. 2006 [21]
Anorectal manometry
BFB group (n = 54/109)
Baseline—6 months, baseline—12 months after starting treatment
x
Increased anal pressure (n, %), (paradoxical) EMG increase (n, %), unable to evacuate balloon (n, %), anal squeeze pressure (mm Hg), rectoanal inhibitory reflex threshold (ml), urge threshold (ml), maximum tolerable volume (ml), compliance (mm Hg) (p < 0.01)
Anal resting pressure (mm Hg) (p ≥ 0.01)
Baseline—24 months after starting treatment
x
Increased anal pressure (n, %), (paradoxical) EMG increase (n, %), unable to evacuate balloon (n, %), anal squeeze pressure (mm Hg), urge threshold (ml), maximum tolerable volume (ml) (p < 0.01)
Anal resting pressure (mm Hg), rectoanal inhibitory reflex threshold (ml), compliance (mm Hg) (p ≥ 0.01)
BFB group vs. laxative group, in favour BFB group (n = 109)
6 and after 12 months after starting treatment
x
Increased anal pressure (n, %), (paradoxical) EMG increase (n, %), unable to evacuate balloon (n, %) (p < 0.01)
Anal resting pressure (mm Hg), anal squeeze pressure (mm Hg), rectoanal inhibitory reflex threshold (ml), urge threshold (ml), maximum tolerable volume (ml), compliance (mm Hg)
24 months after starting treatment
x
No parameter (p < 0.01)
All parameters (p ≥ 0.01)
Koutsomanis et al. 1994 [22]
Anorectal manometry
Study group (n = 20)
Baseline—after treatment
x
Paradoxical contraction on evacuation straining (n pre: n = 15/20, n post: n = 0/20, (p : n.a.))
Anal resting pressure, anal squeeze pressure, anorectal sensation (p : n.a.)
Battaglia et al. 2004 [24]
Anorectal manometry
Patients with PF dyssynergia (n = 14/24)
Baseline—3 months after treatment
x
Sensation threshold (mm Hg; p = 0.042), paradoxical increase in intra-anal pressure during straining (p : n.a.)
Maximum basal pressure of internal anal sphincter, maximum rectum tolerable volume (p ≥ 0.05)
Patients with slow transit (n = 10/24)
Baseline—3 months after treatment
x
Maximum rectum tolerable volume (ml), (p = 0.008)
Maximum basal pressure of internal anal sphincter (mm Hg), sensation threshold (mm Hg) (p ≥ 0.05)
Wang et al. 2003 [25]
Anorectal manometry
Study group (n = 50)
Baseline—after treatment
x
Anal canal average rest pressure (mm Hg) rectum: initial sense (ml), (p < 0.05)
Anal canal voluntary squeeze (mm Hg), rectum: maximum tolerable volume (ml) and compliance (ml/mm Hg), (p ≥ 0.05)
Ba-Bai-Ke-Re et al. 2014 [26]
Anorectal manometry
BFB group vs. laxative group, in favor BFB group (n = 88)
Baseline—after treatment
x
Anorectal resting pressure, anorectal squeeze pressure (mm Hg) (p < 0.05)
Chiarioni et al. 2005 [28]
Gut transit time
PF dyssynergia (n = 34) vs. slow transit only (n = 12)
Baseline—1/6/12/24 months after treatment
x
% of patients with abnormal transit test: baseline: 100%; at all f/u: PF dyssynergia vs. slow-transit-only: sign. smaller % of patients with abnormally delayed transit, p < 0.05
Balloon defecation test
Patients with PF dyssynergia (n = 34)
Baseline—after treatment (1, 6, 12, 24 months)
x
Baseline: 0%, after treatment (1–24 months): 82–85% could defecate the balloon within 5 min (p : n.a.)
Anorectal manometry
Patients with PF dyssynergia (n = 34)
Baseline—after treatment (1, 6 months)
x
Urge threshold (ml), maximum tolerable pressure (mm Hg), straining rectal pressure (mm Hg), dyssynergia (balloon defecation test) (p < 0.05)
Anal canal resting pressure (ml), rectoanal inhibitory reflex threshold (ml), compliance (mm Hg100ml) p ≥ 0.05
Patients with slow transit only (n = 12)
Baseline—after treatment (1, 6 months)
x
Urge threshold (ml) (p < 0.05)
Anal canal resting pressure (ml), rectoanal inhibitory reflex threshold (ml), maximum tolerable pressure (mm Hg), compliance (mm Hg100ml), straining rectal pressure (mm Hg) (p ≥ 0.05)
Patients with PF dyssynergia (n = 34) vs. slow transit only (n = 12) in favour of PF dyssynergia
After 1, 6 months
x
Rectoanal inhibitory reflex threshold (ml; only after 1 month), after 1, 6 months: urge threshold (ml), maximum tolerable pressure (mm Hg), p < 0.01
Rectoanal inhibitory reflex threshold (ml, only after 6 months), after 1, 6 months: anal canal resting pressure (ml), rectoanal inhibitory reflex threshold (ml, only after 6 months), compliance (mm Hg100ml), straining rectal pressure (mm Hg) (p ≥ 0.01)
Parker et al. 2019 [31]
Anorectal manometry
Whole study group (constipation, fecal incontinence, rectal pain) (n = 130)
Baseline—after treatment
x
Resolved dyssynergic manometric pressure profile, balloon expulsion test < 1 min in n = 27/130, (p : n.a.)
Constipation + dyssynergic defecation (n = 33/130)
Baseline—after treatment
x
Resolved dyssynergic manometric pressure profile, balloon expulsion test < 1 min in n = 13/53, (p : n.a.)
Constipation without dyssynergic defecation (n = 3/130)
Baseline—after treatment
x
Improvement in anorectal manometry profile (resolved dyssynergic manometric pressure profile, balloon expulsion test < 1 min) in n = 2/3, (p : n.a.)
Rectal pain (n = 3/130)
Baseline—after treatment
x
Resolved dyssynergic manometric pressure profile, balioon expulsion test < 1 min in n = 2/3, (p : n.a.)
Male chronic pelvic pain syndrome, Urological Chronic Pelvic Pain Syndrome
Cornel et al. 2005 [34]
Levator ani EMG
Study group (n = 18)
Baseline—after treatment
x
Mean pelvic muscle tonus↓ (mcV, p < 0.0012)
He et al. 2010 [36]
Urodynamics (uroflowmetry + EMG)
Study group (n = 21)
Baseline—10 wks after treatment
x
Max. flow rate (ml/s), max. detrusor pressure-storage phase (cmH2O), max. urethra closure pressure (cmH2O), max. urethral pressure (cmH2O) (p < 0.05)
Female chronic pelvic pain
Glazer et al. 1995 [38]
PF EMG
Study group (n = 33)
Baseline—after treatment (=after 6th assessment)
x
Muscle contractile strength = mean contraction amplitude (mcV) ↑, mean relaxation amplitude ↓ (mcV) (p < 0.0001), SD: measure of the stability of the muscle at rest improved (p : n.a.)
McKay et al. 2001 [39]
PF EMG
Study group (n = 29)
After 1 month—after 6 months
x
Mean maximum contractile strength ↑ (mcV): after 1st month: 16.42 in n = 29, after 6th month: 42.73 in n = 11 (dropout n = 18), (p : n.a.)
Gentilcore-Saulnier et al. 2010 [40]
PF EMG
IG (provoked vestibulodynia, n = 11)
Baseline—after treatment
x
Tonic surface EMG resting activity: deep (p = 0.86) or superficial (p = 0.32) PF muscle layer
Baseline—after treatment
x
PF muscle maximum voluntary contractile activity: deep: p = 0.82; superficial: p = 0.50
Baseline—after treatment
x
Superficial PFM EMG activity pain responses ↓ (mcV), (p < 0.0001)
Deep PF layer EMG activity pain response (mcV), (p = 0.72)
IG (provoked vestibulodynia, n = 11) vs. healthy CG (n = 11)
Baseline, pretreatment
x
Sign. greater superficial PFM EMG activity pain responses (mcV) in pretreatment IG compared to CG (p = 0.003); sign. higher tonic activity in superficial PFM in pretreatment IG compared to CG (p = 0.04)
No sign. difference pretreatment IG vs. CG for: PFM maximum voluntary contractile activity for deep (p = 0.81) and superficial (p = 0.36) PFM; EMG pain responses of the deep PFM (p = 0.89); deep PFM tonic activity (p = 0.18)
IG (provoked vestibulodynia, n = 11) vs. healthy CG (n = 11)
After treatment
x
No sign. difference between posttreatment IG and CG: tonic surface EMG resting activity at both superficial (p = 0.82) and deep (p = 0.31) PFM; PFM maximum voluntary contractile activity for deep (p = 0.54) and superficial (p = 0.90) PFM; EMG activity pain response (mcV) for deep (p = 0.98) or superficial (p = 0.18) PFM
Digital intravaginal assessment
IG (n = 11 with pelvic floor dyssynergia)
Baseline—after treatment
x
PFM tone ↓ (p < 0.001), PFM flexibility ↑ (p = 0.01), PFM post-contraction relaxation capacity ↑ (p = 0.05), PFM strength ↑ (p = 0.04)
IG (n = 11 with provoked vestibulodynia) vs. healthy CG (n = 11)
Baseline
x
Pretreatment PVD group vs. CG: PFM tone: sign. higher in PVD group (p = 0.005), PFM flexibility: sign. lower in PVD group (p = 0.01), PFM relaxation: sign. less ability to relax PFM in PVD group (p = 0.02) compared to CG
Pretreatment PVD group vs. CG: no significant difference in PFM strength (p = 0.54)
IG (n = 11 patients with provoked vestibulodynia) vs. healthy CG (n = 11)
After treatment
x
posttreatment PVD group vs. CG: no sign. difference in PFM tone (p = 0.30), PFM flexibility (p = 1.00), PFM relaxation (p = 0.47), PFM strength (p = 0.12)
Philips et al. 1992 [42]
Perivaginal EMG
IG 1 (BFB group, n = 10)
Baseline—after treatment
x
Mean EMG scores (seated to void, tensing, relaxing, voiding; mcV) p > 0.05
Bennink et al. 1982 [44]
EMG lower abdomen
IG1 (n = 5) vs. IG2 (n = 5)
x
BFB group maintained a significantly lower level of EMG muscle tone (mcV/s) of lower abdomen on 1st day of menstruation compared to massage group (p < 0.05)
Vagedes et al. 2019 [45]
Heart rate variability
BFB group (n = 20)
Baseline—after treatment
x
SDNNl, RMSSD, LF/HF ratio (p > 0.05)
BFB (n = 20) vs. CG (n = 17)/BFB vs. massage (n = 23)
After treatment
x
Same values: BFB vs. CG/massage vs. BFB group post treatment: p > 0.05
Lúcio et al. 2014 [47]
Intravaginal digital examination
IG1: EMG BFB + PF training + sham NMES (n = 6)
Baseline—after treatment
x
PF muscle function according to PERFECT scheme ↑ [69]: power (0–5 = max. strength), endurance (sec), dynamic endurance (no. of repetitions), fast contractions (no. of repetitions): p < 0.05
PF muscle palpation score: PF muscle tone (score: −3 to +3 = very hypertonic), flexibility (score 0–4 = very flexible), ability to relax PF muscles (Score 0–4 = spastic): p > 0.05
Chronic pelvic pain in children
Ebiloglu et al. 2016 [52]
Urodynamics
Study group (n = 136)
Baseline—after treatment (6 months)
x
No. of patients with positive perineal EMG activity while urinating (p < 0.001)
Urodynamics
Study group (n = 136)
Baseline—after treatment (6 months)
x
Mean voided volume (ml, p = 0.019), mean maximum flow rate (ml/s, p = 0.012)
Mean average flow rate (ml/s, p = 0.209), mean voiding time (s, p = 0.345), post-void residual volume (ml, p = 0.374)
Ergin et al. 2016 [53]
Urodynamics
Intervention group (n = 39)
Baseline—after treatment (6 months)
x
Uroflowmetry—EMG, post-void residual volume (p < 0.001)
Li et al. 2006 [54]
Urodynamics
IG (n = 25)
Baseline—after treatment
x
Maximum urinary flow rate (ml/s), p = 0.001
Postvoid residual urine volume (ml), p = 0.08
BFB biofeedback, CG control group (no intervention), EGS electrogalvanic stimulation, EMG electromyography, f/u follow-up, IG intervention group, LAS levator ani syndrome, LF/HF ratio  ratio of two bands from frequency domain analysis: LF band (0.04–0.15 Hz) indicating sympathetic and parasympathetic activity, HF band (0.15–0.40 Hz) indicating parasympathetic activity; mcV microvolt, ml mililiter, ml/ mililiter per second, no. number(s), PF pelvic floor, PFM pelvic floor muscle(s), RMSSD root mean square of successive differences; s second(s), SD standard deviation, SDNN standard deviation of normal to normal, vs. versus, wk, wks week(s)

Data synthesis

An attempt was made to bundle data for a meta-analysis; however, due to the substantial heterogeneity of study designs, patient characteristics, interventions and effect measures, a meta-analysis was not possible as results are considered unreliable when a small number of heterogeneous studies are assessed [70]. Rather, a narrative synthesis of study results was performed [71], and findings were juxtaposed in the respective tables to provide a comprehensive overview of the current literature.

Quality assessment

As trials differed in their study design, the McMaster Critical Review Form—Quantitative Studies [72, 73] was chosen for assessing the methodological quality of all studies included. This critical appraisal tool allows comparisons across different types of quantitative study designs due to its generic composition [5, 74, 75]. It comprises 15 items that evaluate method rigor and bias and has a guideline for completing the questionnaire that facilitates consistency in interpretation and application [72, 74]. In its original form, the tool did not provide a numerical summation. Based on previous reviews [5, 74, 75], for better comparability between included studies, a sum score of the respective subdomains was established. Each question is rated with either “yes” (1 point), “no”, “not addressed” or “not applicable (N/A)” (0 points). In this arbitrary scoring system, higher scores indicate higher methodological quality, resulting in a possible total score of 14 points [5].
In addition, studies with an RCT design were evaluated using the Physiotherapy Evidence Database—PEDro score, a valid and reliable tool for assessing the methodological quality and completeness of statistical reporting of randomized and quasi randomized controlled trials in physiotherapy [12, 7681]. The tool evaluates internal validity and interpretability [82]. Eleven items are rated yes or no (1 or 0 points) according to whether the criterion is clearly satisfied in the study. A total PEDro score is achieved by adding the ratings of items 2–11 for a total score between 0 and 10. Higher scores indicate superior methodological quality. Studies with 9–10 points are considered excellent, 6–8 good, 4–5 fair and < 4 poor quality [80].

Results

Study selection

A total of 651 studies published between 1978 and 29 July 2020 were found and screened for eligibility by title and abstract. After eliminating duplicates, 389 studies were rejected as non-includable, 83 studies were selected for full-text analysis and 37 articles corresponded to the inclusion criteria. Details on the systematic literature search and the selection process are presented in Fig. 1.

Study characteristics

Quality assessment

Table 8 shows the quality assessment using the Mc Master Critical Review Form—Quantitative Studies Tool for assessing the risk of bias of all studies included.
Table 8
Methodological quality assessment: evaluating all studies included (n = 37): McMaster Critical Review Form (CRF)—Quantitative Studies [72]
Study
Study design
Was the purpose stated clearly?
Was relevant background literature reviewed?
Was the sample described in detail?
Was sample size justified?
Were the outcome measures reliable?
Were the outcome measures valid?
Intervention was described in detail?
Contamination was avoided?
Cointerventiona was avoided?
Results were reported in terms of statistical significance?
Were the analysis method(s) appropriate?
Clinical importance was reported?
Drop-outs were reported?
Conclusions were appropriate given study methods and results?
Total score (sum score)
Anorectal pain syndrome
Chiarioni et al. 2010 [16]
RCT, 3 arms
Yes
Yes
Yes
Yes
N.add.a
N.add.a
Yes
Yes
No
Yes
Yes
Yes
No
Yes
10
Heah et al. 1997 [17]
Non-RCT
Yes
Yes
No
No
N.add.a
N.add.a
Yes
N/A
No
Yes
Yes
Yes
No
Yes
7
Ger et al. 1993 [18]
Non-RCT
Yes
Yes
Yes
No
N.add.
N.add.
Yes
No
N.add.
No
No
Yes
Yes
Yes
7
Gilliland et al. 1997a [19]
Non-RCT, retrospective
Yes
Yes
Yes
No
N.add.
N.add.
No
N/A
N.add.
Yes
Yes
Yes
Yes
Yes
8
Grimaud et al. 1991 [20]
Non-RCT
Yes
Yes
Yes
No
N.add.a
N.add.a
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
11
Constipation
Chiarioni et al. 2006 [21]
RCT, 2 arms
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
13
Koutsomanis et al. 1994 [22]
Non-RCT
Yes
Yes
No
No
N.add.a
N.add.a
Yes
N/A
No
Yes
Yes
Yes
Yes
No
7
Chiotakakou-Faliakou et al. 1998 [23]
Non-RCT, retrospective
Yes
Yes
Yes
No
N.add.
N.add.
Yes
N/A
No
Yes
Yes
Yes
Yes
Yes
9
Battaglia et al. 2004 [24]
Non-RCT
Yes
Yes
Yes
No
N.add.a
N.add.a
Yes
N/A
No
Yes
Yes
Yes
No
Yes
8
Wang et al. 2003 [25]
Non-RCT
Yes
Yes
Yes
No
N.add.a
Yes
Yes
Yes
No
Yes
Yes
Yes
No
Yes
10
Ba-Bai-Ke-Re et al. 2014 [26]
RCT, 2 arms
Yes
Yes
no
Yes
N.add.a
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
11
Roy 2000 [27]
Non-RCT, retrospective
Yes
Yes
Yes
No
N.add.
N.add.
Yes
N/A
No
Yes
Yes
Yes
No
Yes
8
Chiarioni et al. 2005 [28]
Non-RCT
Yes
Yes
Yes
No
N.add.a
N.add.a
Yes
N/A
No
Yes
Yes
Yes
Yes
Yes
9
Zhu et al. 2011 [29]
Non-RCT
Yes
Yes
Yes
Yes
Yes
Yes
Yes
N/A
No
Yes
Yes
Yes
Yes
No
11
Gilliland et al. 1997b [30]
Non-RCT, retrospective
Yes
Yes
Yes
No
N.add.
N.add.
No
N/A
No
Yes
Yes
Yes
Yes
No
7
Parker et al. 2019 [31]
Non-RCT, retrospective
Yes
Yes
No
No
N.add.
No
No
N/A
N.add.
No
No
Yes
Yes
Yes
5
Male chronic pelvic pain syndrome, Urological Pelvic Pain Syndrome
Clemens et al. 2000 [32]
Non-RCT
Yes
Yes
No
No
N.add.
N.add.
Yes
N/A
N.add.
Yes
Yes
Yes
Yes
Yes
8
Cornel et al. 2005 [34]
Non-RCT
Yes
Yes
Yes
No
Yes
Yes
Yes
N/A
N.add.
Yes
Yes
Yes
Yes
Yes
11
Yang et al. 2017 [35]
Non-RCT, retrospective
Yes
Yes
Yes
No
N.add.a
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
12
He et al. 2010 [36]
Non-RCT, retrospective
Yes
No
No
No
N.add.a
N.add.a
No
N/A
Yes
Yes
Yes
Yes
No
Yes
6
Female chronic pelvic pain
Schmitt et al. 2017 [37]
Non-RCT
Yes
Yes
No
No
N.add.a
Yes
Yes
N/A
N.add.
Yes
Yes
Yes
Yes
Yes
9
Glazer et al. 1995 [38]
Non-RCT
No
Yes
Yes
No
N.add.a
N.add.a
Yes
N/A
No
Yes
Yes
Yes
No
Yes
7
McKay et al. 2001 [39]
Non-RCT
Yes
Yes
Yes
No
N.add.a
N.add.a
Yes
N/A
N.add.
Yes
Yes
Yes
Yes
Yes
9
Gentilcore-Saulnier et al. 2010 [40]
Non-RCT
Yes
Yes
Yes
Yes
Yes
Yes
Yes
N/A
Yes
Yes
Yes
Yes
No
Yes
12
Bendana et al. 2009 [41]
Non-RCT, retrospective
Yes
Yes
Yes
No
N.add.
No
Yes
N/A
N.add.
Yes
Yes
Yes
Yes
Yes
9
Philips 1992 [42]
RCT
Yes
Yes
Yes
No
N.add.a
N.add.a
No
Yes
N.add.
Yes
Yes
Yes
No
Yes
8
Hart et al. 1981 [43]
Non-RCT, 2 arms
Yes
Yes
Yes
No
N.add.
N.add.
Yes
Yes
N.add.
Yes
N.add.
Yes
Yes
No
8
Bennink 1982 [44]
RCT, 3 arms
Yes
Yes
No
No
N.add.
N.add.
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
9
Vagedes et al. 2019 [45]
RCT, 3 arm
Yes
Yes
Yes
Yes
Yes
N.add.a
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
12
Starr et al. 2013 [46]
Non-RCT, retrospective
Yes
Yes
Yes
Yes
N.add.
No
Yes
N/A
No
Yes
Yes
Yes
Yes
Yes
10
Lúcio et al. 2014 [47]
RCT, 3 arms
Yes
Yes
Yes
No
N.add.a
Yes
Yes
Yes
N.add.
Yes
Yes
Yes
Yes
Yes
11
Aalaie et al. 2020 [48]
RCT, 2 arms
Yes
Yes
Yes
Yes
Yes
N.add.a
Yes
Yes
N.add.
Yes
Yes
Yes
Yes
Yes
12
Chronic pelvic pain in children in children
Hoebeke et al. 2004 [51]
Non-RCT
Yes
Yes
Yes
No
N.add.
N.add.
Yes
N/A
No
No
N.add.
Yes
No
No
5
Ebiloglu et al. 2016 [52]
Non-RCT, retrospective
Yes
Yes
Yes
Yes
N.add.a
N.add.a
Yes
N/A
N.add.
Yes
Yes
Yes
No
Yes
9
Ergin et al. 2016 [53]
Non-RCT
Yes
Yes
Yes
No
N.add.a
Yes
No
N/A
N.add.
Yes
Yes
Yes
Yes
Yes
9
Li et al. 2006 [54]
Non-RCT
Yes
Yes
Yes
No
N.add.a
Yes
No
N/A
Yes
Yes
Yes
Yes
Yes
Yes
10
Musculoskeletal, low back pain, myofascial pain
Kent et al. 2015 [55]
RCT, 2 arms
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
13
McMaster CRF: 15 items; total score = 14; study design item does not contribute to total score; codes: yes = 1, no = 0, N/A (not applicable) = 0, N.add not addressed (no information provided in the study) = 0 [5]; anot addressed in respective paper, but at least one main outcome tool was judged to be valid/reliable by review authors (described in the literature)
Total score: higher scores indicate higher methodological quality, resulting in a possible total score of 14 points.
All studies but one were judged to have clearly stated the purpose of the study [38] and to have reviewed the relevant background literature [36]. The majority of the studies (29/37) gave enough detail on important sample characteristics. Only 10/37 studies stated how they arrived at the sample size. A minority of studies explicitly stated to have used reliable [21, 29, 34, 40, 45, 48, 55] and valid [21, 25, 26, 34, 35, 37, 40, 47, 5355] outcome measures. For several tools, however, the psychometric properties are described in the literature. If at least one main outcome tool was used that is described in the literature, studies were marked with an asterisk. The majority of the studies (30/37) was judged to have described the intervention in detail. Where applicable/where addressed, most studies (13/14) were assessed to have avoided contamination through inadvertent treatment but not to have avoided co-interventions (17/23) as in many cases, subjects were taking medication during the study period (e.g. analgesics, laxatives in anorectal disorders). Most studies (34/37) reported results in terms of statistical significance, chose analysis methods appropriate for the study and the outcomes (32/35) and reported on drop-outs (26/37). All studies (37/37) were assessed to have discussed the relevance of the results to clinical practice and the majority of the studies (32/37) were judged to draw appropriate conclusions, given the study methods and results. The arbitrary sum score ranged between 5 and 13 (mean 9.2).
Table 9 shows the quality assessment of the 9 RCTs according to the PEDro scale [81], resulting in 2 studies of fair [26, 55] and 7 studies of good [16, 21, 42, 44, 45, 47, 48] quality. The mean PEDro score of these studies was 6 (range 5–8). All studies were randomized (9/9), analyzed the between-group difference (9/9), reported point estimate and variability (9/9) and had similar groups at baseline (9/9). Some studies had a concealed allocation (4/9), 4 out of 9 studies reported adequate follow-up. The majority of the studies did not have blinded participants (8/9), blinded therapists (9/9) or blinded assessors (5/9). In 7 out of 9 studies all subjects for whom outcome measures were available received the treatment or control condition as allocated or, if this was not possible, data for at least one key outcome were analyzed by intention to treat [81].
Table 9
Methodological quality assessment, evaluating the included randomized controlled trials (n = 9): Physiotherapy Evidence Database (PEDro) scale [81]
Criteria
Eligibility criteria and source
Random allocation
Concealed allocation
Baseline comparability
Blinding of subjects
Blinding of therapists
Blinding of assessors
Adequate follow-up (>85%)
Intention-to-treat analysis
Between-group statistical comparisons
Reporting of point measures and measures of variability
Total score
Quality
Chiarioni et al. 2010 [16]
Yes
Yes
Yes
Yes
No
No
Yes
Yes
Yes
Yes
Yes
8
Good
Chiarioni et al. 2006 [21]
Yes
Yes
Yes
Yes
No
No
Yes
No
No
Yes
Yes
6
Good
Ba-Bai-Ke-Re et al. 2014 [26]
Yes
Yes
No
Yes
No
No
No
No
Yes
Yes
Yes
5
Fair
Philips et al. 1992 [42]
Yes
Yes
No
Yes
No
No
Yes
Yes
Yes
Yes
Yes
7
Good
Bennink et al. 1982 [44]
Yes
Yes
No
Yes
No
No
No
Yes
Yes
Yes
Yes
6
Good
Vagedes et al. 2019 [45]
Yes
Yes
Yes
Yes
No
No
No
No
Yes
Yes
Yes
6
Good
Lúcio et al. 2014 [47]
No
Yes
No
Yes
Yes
No
Yes
No
No
Yes
Yes
6
Good
Aalaie et al. 2020 [48]
Yes
Yes
Yes
Yes
No
No
No
Yes
Yes
Yes
Yes
7
Good
Kent et al. 2015 [55]
Yes
Yes
No
Yes
No
No
No
No
Yes
Yes
Yes
5
Fair
PEDro scale: 11 items; total score: 10; eligibility criteria item does not contribute to total score; codes: yes = 1, no = 0; quality score: < 4 = poor quality, 4–5 = fair quality, 6–8 = good quality, 9–10 = excellent quality [80]
Table 2 gives an overview of the characteristics of the included studies, additionally outlining study design, comparison characteristics and sample sizes.

Participants

A total of 2913 patients with pelvic pain conditions and 75 healthy subjects were included in 37 studies, of whom 2489 patients were assigned to groups receiving biofeedback. The other subjects received different treatment, no intervention or standard care (Table 4).
Table 3 (and Table 2) present the patient characteristics: 5 studies investigated patients with anorectal pain syndromes [1620], 11 studies evaluated patients with constipation [2131], 4 studied men with nonbacterial chronic prostatitis [32, 3436], 12 investigated females with CPP (vulvar vestibulitis syndrome/dyspareunia, pelvic floor dysfunction, dysmenorrhea, sexual dysfunction, or urethral syndrome) [3745, 47, 48], 1 evaluated patients with low back pain [55] and 4 studied children with pelvic floor spasm [51], overactive bladder syndrome [52], dysfunctional voiding [53] or pubertal chronic prostatitis [54]. Overlapping diagnoses were common. The literature search only revealed chronic (no acute) pelvic pain conditions treated with biofeedback. The majority of the studies (24/37) stated that a secondary cause of pelvic pain had been excluded [1620, 2228, 30, 32, 3436, 38, 41, 42, 48, 5254]. One study enrolled patients with multiple sclerosis as an underlying disease [47], 6 studies [18, 20, 23, 25, 27, 30] indicated that the included subjects suffered from some kind of psychopathology (anxiety, depression, emotional trauma), 3 studies explicitly excluded patients with a psychopathologic disorder [16, 45, 48]. A total of 15 studies [18, 20, 21, 2328, 32, 35, 38, 39, 42, 52] stated that conventional treatment including medication, changes in diet and interventions had failed prior to biofeedback.
Age ranged between 11 and 96 years in studies mainly enrolling adults. The mean age for trials involving children was 8.4 years [5153] and 16.5 years for the study investigating adolescents [54].

Intervention

Table 4 presents an overview of the study intervention characteristics. 27 study protocols applied biofeedback only (together with counselling/education, pelvic floor exercises and home exercises, which are counted as part of the biofeedback intervention) [17, 18, 2032, 34, 36, 38, 39, 4245, 48, 51, 53, 54], others applied biofeedback as a multimodal treatment component (including psychological techniques [16, 19], electrotherapy [35, 37, 40, 41, 46, 47], medication [37], manual therapy [40] or guidelines-based care [51, 55]). Most studies evaluated outcome after the treatment, some (re)evaluated 2–3 months after the end of the treatment [16, 21, 24, 26, 35, 36, 4143, 48], some had a long-term follow-up (6–mean 28 months) [16, 18, 2128, 32, 38, 51].
Anorectal manometric systems and surface EMG techniques were the commonly applied anorectal physiological assessment tools in studies dealing with anorectal disorders. Male chronic pelvic pain syndromes used EMG-guided training [32, 3436]. In urogenital phenotypes in children and adolescents, both urodynamics and perineal EMG were used. In female chronic pelvic pain syndromes, most studies used pelvic floor EMG to evaluate pelvic floor function. Three studies on patients with dysmenorrhea [4345] aimed at increasing general relaxation by using heart rate variability training, skin temperature training and EMG of the frontalis and lower abdominal muscles.
Overall, the biofeedback training extent was largely heterogeneous, 2–30 sessions were administered, lasting between 10 and 60 min, for up to 6 months. Most designs applied biofeedback weekly, less often sessions were scheduled twice or three times a week or once every 2 weeks. Biofeedback in a home-based setting was applied daily in 3 studies on gynecological disorders [38, 39, 45]. Treating anorectal disorders, four large trials by Chiarioni et al. [16, 21, 28] and Ba-Bai-Ke-Re et al. [26] proved 5 weekly biofeedback sessions of 30min to be successful (Table 4).
Of the studies 11 reported that no biofeedback-related side effects had occurred [1619, 21, 25, 29, 30, 35, 48, 52] and 1 study noted a transient skin irritation related to the use of a tape [55].

Outcome

Primarily evaluated outcomes: pain intensity, overall symptom improvement, quality of life
Heterogeneous assessment methods were used to evaluate primary outcome measures within a certain phenotype (Tables 5 and 7). Pain was assessed using either visual analog scale (VAS) or numeric rating scale (NRS) [16, 17, 32, 35, 3740, 45, 55, 60] or subdomains of relevant questionnaires [29, 3436, 47, 48, 54]. In terms of overall symptom improvement, several studies used symptom scores [26, 32, 3436, 41, 43, 44, 47, 48, 5254]. Apart from using standardized questionnaires, many studies reported the success rate, given as the number or percentage of patients who stated subjective pain or symptom improvement. Definitions regarding the extent of symptom improvement differed between studies (Tables 5, 6 and 7).
Quality of life was only assessed in 9 studies [26, 29, 3436, 40, 41, 45, 54], applying questionnaires, subdomains of validated symptom scores or impact on quality of life on a VAS or NRS scale [60].
Outcome tools together with references of the respective questionnaires are outlined in Tables 5 and 7.
Secondarily evaluated outcomes: physiological parameters
Pelvic floor function was assessed using manometric devices, urodynamic devices as well as surface EMG techniques and digital examination. One study observed general relaxation through heart rate variability measures [45].

Effect of biofeedback interventions on pain, overall symptoms

Table 5 presents the effect of biofeedback-assisted interventions on pain and overall symptom improvement in detail. To provide a better overview, the main conclusions drawn by the respective authors are additionally subsumed in Table 2.
Only three [16, 17, 19] out of five studies evaluating anorectal pain syndrome provided p-values for pain outcomes. Significant anorectal pain relief could be shown, whereby patients who finished had superior results compared to those who discharged themselves before completion of treatment [19]. A large RCT of good quality by Chiarioni et al. 2010 found biofeedback to be superior to electrogalvanic stimulation and local massage therapy both in the short and long term, whereby these differences were only significant in patients with a highly likely levator ani syndrome (tenderness of the levator ani muscle on the rectal examination) [16].
Eleven studies investigated patients with constipation: 2 RCTs of adequate sample size studied patients with dyssynergic defecation [21, 26] and found that biofeedback significantly decreased abdominal pain compared to laxatives (polyethylene glycol) [21, 26] with long-term effects and huge effect sizes significantly different from zero [21]. The same two RCTs found biofeedback superior to laxatives in terms of constipation symptom improvement with very large effect sizes [26].
Several of the remaining nine non-RCTs found pain [2224, 27, 29] and constipation symptoms [22, 23, 25, 27, 29, 31] improved after biofeedback, at least for certain subgroups. Studies showed contradictory results regarding the question of whether biofeedback only benefited patients with PF dyssynergia or also patients with prolonged transit time. Some studies found that biofeedback improved (long term) symptoms for pelvic floor dyssynergia [22, 24, 28] but not for slow transit constipation [24, 28], others found that both phenotypes benefited equally from treatment [23, 25, 27].
With respect to the 11 studies on female chronic pelvic pain, several could improve pain [3740, 48] or symptoms [38, 39, 41, 43, 44, 4648], at least in the longer term. Again, several studies lacked p-values or measures of clinical relevance.
The 4 urogenital studies on children and adolescents and 4 studies on men with chronic prostatitis mostly found improvements in pain [32, 3436, 51, 52, 54] and urological symptoms [32, 3436, 5254], with medium to huge effect sizes in Yang et al. [35].

Effect of biofeedback interventions on quality of life

Nine studies used biofeedback to improve pelvic floor function and found a significant improvement in the quality of life postintervention in eight trials (Table 6). The findings came along with small [29, 35] to huge [26, 36] effect sizes, with 5 studies showing a significant effect for at least some outcomes [26, 29, 35, 36, 45]. A home-based heart rate variability training failed to significantly improve quality of life compared to standard care [45].

Effect of biofeedback interventions on physiological parameters

Table 7 presents significant changes in physiological outcome assessment following biofeedback interventions. Biofeedback training could significantly improve at least some manometric values in 9 [16, 2022, 2426, 28, 31] out of 10 studies on anorectal dysfunction. In Heah et al. [17] manometric values did not significantly change posttreatment. Six [16, 17, 21, 22, 24, 28] out of 9 studies did not improve resting anal canal pressures. Studies on constipation and dyssynergic defecation found that paradoxical contraction on evacuation [21, 22, 24, 28, 31] and the ability to defecate a balloon [21, 28, 31] could be improved. Patients with dyssynergic defecation could improve more manometric values than patients with slow transit constipation [28]. A landmark trial on anal pain syndrome showed that patients with a tenderness of the levator ani muscle on digital palpation could improve more manometric values than patients without tenderness on the rectal examination [16].
In female chronic pelvic pain, four studies did improve EMG values of the pelvic floor or lower abdomen [38, 39, 44, 52] whereas two (mostly) failed to do so [40, 42].
In urologic phenotypes all [36, 53] or some [52, 54] urodynamic measures could be significantly improved.

Discussion

Quality

This systematic review included 37 quantitative studies and found tentative evidence that biofeedback-assisted training interventions can improve the primarily evaluated outcomes pain, overall symptoms, and quality of life. Results should be considered with caution due to quality issues of many of the included trials. Only 9 studies had an RCT design, out of which 7 were judged to be of good quality according to PEDro assessment. Many studies were likely underpowered and did not provide a sample size calculation.
Biofeedback is a modality to improve self-efficacy and learning based on operant conditioning [83]. Biofeedback is not used as an intervention on its own but is rather an adjunctive tool to other standard interventions (e.g. pelvic floor exercises, education, lifestyle modification [84]). At times, studies applied biofeedback together with additional physical modalities. Besides, patients were often under medication during the study period for symptom control. Therefore, the single effect of biofeedback intervention is difficult to extract. Biofeedback protocols are difficult to compare between institutions as treatment protocols, biofeedback devices and training amount varied considerably.
Most studies compare improvements within an intervention group which reduces the strength of evidence. Most authors drew their conclusions based on the statistical significance, only two papers [45, 48] reported on effect sizes and confidence intervals of pain and symptom outcomes. Ten studies [21, 26, 29, 35, 36, 4044] provided data to calculate effect sizes and confidence intervals to evaluate the clinical relevance of the results [85]. The majority of the studies did not perform a post hoc analysis or a correction for multiple testing. Some studies used nonvalidated outcomes to evaluate pain and overall improvement.
The impossibility to fulfil certain quality requirements such as blinding of participants or the administration of placebo treatment, which are standard in pharmacological studies, is immanent to the biofeedback training method and setting.
Given these limitations, the statements that were drawn conducting this review should be understood as tentative evidence and should be considered with caution. Three RCTs of above-average quality with respect to sample size, study design, and reporting [16, 21, 45] are given special attention in the subsequent discussion.

Efficacy of biofeedback in certain phenotypes and existing recommendations of guidelines

For anorectal disorders, such as dyssynergic defecation and levator ani syndrome, guidelines exist that state that biofeedback is the preferred treatment for chronic anal pain syndrome (level of evidence IA), [2] and is considered useful in the short-term treatment of levator ani syndrome with dyssynergic defecation (level of evidence IIB) [83]. Biofeedback is recommended for the short-term and long-term treatment of constipation with dyssynergic defecation (level of evidence IA), which is the most common defecation disorder, affecting about 40% of patients with chronic constipation [83]. Biofeedback seems to benefit patients with dyssynergic defecation above other types of constipation [24, 28, 83, 86]. In PF dyssynergia, a landmark trial by Chiarioni et al. [21] found biofeedback to be superior to laxatives (polyethylene glycol), two other RCTs [87, 88] (not considered in this review) also considered it superior to alternative treatments (diazepam), placebo, sham feedback and standard treatment [86]. The pathophysiology of levator ani syndrome seems to be similar to that of dyssynergic defecation, thus similar techniques and protocols have been used [16]. Both EMG and pressure-based biofeedback therapy protocols appear to be efficacious in restoring a normal pattern of defecation, but larger comparative trials are lacking [83]. Surface EMG probes are cheaper, more durable and usually provide a one or two-channel display [83]. Manometric systems are more expensive, have a multiple channel display and can facilitate rectoanal coordination and sensory training because they have a balloon and rectal sensor [83, 86].
In patients with vulvar vestibulitis syndrome (vulvodynia, dyspareunia), preliminary evidence has suggested that altered muscle abnormalities (as shown by altered EMG activity such as elevated resting activity, reduced muscle contraction strength, muscle instability) are present and EMG biofeedback muscle rehabilitation, therefore, is beneficial [1, 38]. According to Mariani, biofeedback should be used as a first-line treatment in moderate to severe vulvar vestibulitis (together with antidepressants and psychological counseling) [89]. Two uncontrolled studies by Glazer et al. and McKay at al. using portable EMG biofeedback devices showed promising results with this indication [38, 39]. Bergeron et al. (not considered in this review) applied the home-based Glazer protocol in an RCT design. They confirmed that EMG biofeedback as well as cognitive-behavioral therapy and vestibulectomy, could improve sexual function and reduce pain (greatest pain reduction in the vestibulectomy group [1, 90, 91]) in the short and long term.

Pros and cons of biofeedback in pelvic pain conditions and criteria to improve treatment success

Biofeedback is a safe method, which has not shown any significant adverse effects. This might make biofeedback an attractive treatment option even in indications with a smaller success rate. As biofeedback is a labor-intensive approach [83] and quite time-consuming for both therapist and patient, it is important to preselect those patients who have a high chance of benefitting from the intervention.
The use of biofeedback to treat pelvic pain is based on the idea that these pain conditions may result from, or are associated with, pelvic floor muscle dysfunction. Digital palpation of pelvic floor muscles should be integrated into routine examination to identify myofascial pain as a primary or contributing source of pelvic pain condition [2, 8]. In anorectal pain conditions, tenderness on rectal examination has shown to be a valid criterion of treatment success [16]. Shoskes et al. identified and grouped six clinical phenotypes (urinary, psychosocial, organ-specific, infection, neurologic, tenderness of skeletal muscles) in the UPOINT classification in patients with urologic CPPS [2, 92, 93]. This classification was implemented to help direction therapy according to phenotypes, thereby improving outcomes [93]. Thus, patients with a musculoskeletal phenotype can be selected who most likely benefit from biofeedback interventions.
In patients with constipation, biofeedback therapy seems to benefit especially patients with dyssynergic defecation [21, 24, 28, 83, 8688].
Another criterion of success might be a center’s capacities to administer a certain amount of training sessions and the patient’s willingness to complete the course of therapy as suggested by the therapist [19]. In patients with chronic constipation and dyssynergic defecation, consensus guidelines on biofeedback therapy [83] recommend 4–6 biofeedback sessions to manage dyssynergic defecation accordingly: 3 sessions [31] achieved a symptom improvement of only 45.3% compared to e.g. 80% achieved by 5 sessions in Chiarioni et al. [21], hence following existing consensus recommendations improves outcome. As biofeedback requires commitment on the patient’s part to take responsibility for their own health, the patient’s motivation and adequate encouragement to complete the course of therapy through the therapist are other important requirements for the therapeutic success [29, 36]. Cognitive impairment in the older population might lead to slower learning and the need for a higher number of treatment sessions [30]. Medical staff should be capable of demonstrating and explaining the method according to the patient’s comprehension and education levels [36]. Similarly, counteracting problems of comprehension by using appropriate explanations and psychological approaches are important in the work with children [54].
The effectiveness of pelvic floor biofeedback training also depends in part on the skills and experience of the biofeedback therapist and the particular techniques that are used to perform the training [28], which is why it is recommended to follow existing consensus guidelines [83].
As the access to biofeedback remains limited in many areas [31] and only a few centers offer biofeedback therapy, home-based self-training program is desirable and is a promising approach in anorectal and gynecologic (vulvar vestibulitis syndrome) disorders [38, 39, 83], at least to continue training after initial training at a center.
With somatoform disorders and related syndromes, the etiology is still not fully understood but evidence supports an interaction of physiological, psychological and interpersonal factors [1]. Therefore, a multimodal treatment strategy can be promoted, using biofeedback, relaxation training and stress management to address physiological and emotional arousal as well as cognitive techniques, psychoeducation and attention training to alter cognitive-perceptual factors, a modification of illness behavior and graded activity [1]. Multidisciplinary management, which is a common approach to many chronic conditions, is still not commonly available in gynecology because of cost factors and limited availability of interested specialists [7]. Yet multidisciplinary, multimodal and phenotype-oriented approaches have been increasingly proposed to deal with gynecologic phenotypes, such as provoked vestibulodynia and myofascial pain as well as with other chronic pelvic pain conditions such as bladder or prostate pain syndrome [2, 8, 90, 93].
Hence, biofeedback is not a complementary or alternative but an additive method for both diagnostic and therapeutic purposes. It should be used in addition to standard care, based on a state of the art concept, if the physician in charge gives the indication.

Limitations of the present review

The authors decided to include any quantitative study type of primary research to present a comprehensive overview of the current literature. This reduces the methodological quality of the trials and thereby the significance of the results.
The search term “pelvic pain” is wide-ranging, yet there are many terms used in literature to describe pain syndromes which are perceived in a certain organ [94] and specific pathologies that cause pelvic pain. Therefore, our pragmatic and generalized search strategy carries the risk of missing relevant articles. Studies evaluating biofeedback on constipated patients were included, yet constipation was not the primary focus of this paper as the pain component is not paramount; however, this phenotype has been researched in depth, and our search term did not reveal all relevant studies available in the literature. As with the phenotype of dyspareunia, the reader is referred to the respective relevant literature [14, 83, 86, 90].
Due to language restrictions, studies that would have otherwise fulfilled the inclusion criteria could not be included.

Conclusion

Several landmark studies demonstrated the efficacy of biofeedback for anorectal disorders. For other phenotypes of chronic pelvic pain, there is tentative evidence that biofeedback-assisted training interventions can improve the outcomes on pain, overall symptoms, and quality of life. Clinical improvements came along with improvements in certain physiological parameters in several studies. Many trials were characterized by methodological limitations, such as a very small sample size, nonvalidated outcomes and a lack of control group. The preliminary positive findings should be investigated further in robust and well-designed randomized controlled trials. Certain factors have been identified that might be relevant for improving biofeedback treatment success.

Implications for future research

Future studies should aim to:
  • conduct a systematic literature review using MeSH terms that more thoroughly evaluate the effect of biofeedback therapy in a certain phenotype (e.g. anorectal disorders, urological chronic pelvic pain syndrome, bladder pain syndrome, gynecologic pelvic pain conditions);
  • list the term “pelvic pain” in the keywords of studies on certain pelvic pain subtypes so that these trials are detected by a literature search on the umbrella term (as chronic pelvic pain comprises many phenotypes);
  • improve the quality of future studies, e.g. by choosing an RCT study design that is based on a sample size calculation, performing a post hoc analysis or a correction for multiple testing;
  • report on the effect size and an estimate of their precision such as the confidence interval to describe the clinical relevance of results;
  • conduct future trials with more homogeneous outcome assessment (to allow future meta-analysis). Ideally, validated questionnaires or pain scales should be used to measure outcome. For stating success rates, an international consensus on the graduation of these rating scales would be beneficial to standardize outcome and improve comparability between study results;
  • continue to evaluate the optimum type and extent of biofeedback interventions for the certain phenotypes;
  • evaluate changes in quality of life and psychological parameters, such as anxiety and depression (as psychological disorders are common comorbidities in patients with chronic pain conditions).

Conflict of interest

B. Wagner, M. Steiner, D.F.X. Huber and R. Crevenna declare that they have no competing interests.
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Literatur
1.
Zurück zum Zitat Nanke A, Rief W. Biofeedback in somatoform disorders and related syndromes. Curr Opin Psychiatry. 2004;17(2):133–8. Nanke A, Rief W. Biofeedback in somatoform disorders and related syndromes. Curr Opin Psychiatry. 2004;17(2):133–8.
3.
Zurück zum Zitat Latthe P, Latthe M, Say L, Gülmezoglu M, Khan KS. WHO systematic review of prevalence of chronic pelvic pain: a neglected reproductive health morbidity. BMC Public Health. 2006;6(1):177. PubMedPubMedCentral Latthe P, Latthe M, Say L, Gülmezoglu M, Khan KS. WHO systematic review of prevalence of chronic pelvic pain: a neglected reproductive health morbidity. BMC Public Health. 2006;6(1):177. PubMedPubMedCentral
4.
Zurück zum Zitat Ahangari A. Prevalence of chronic pelvic pain among women: an updated review. Pain Physician. 2014;17(2):E141–7. PubMed Ahangari A. Prevalence of chronic pelvic pain among women: an updated review. Pain Physician. 2014;17(2):E141–7. PubMed
5.
Zurück zum Zitat Klotz SGR, Schön M, Ketels G, Löwe B, Brünahl CA. Physiotherapy management of patients with chronic pelvic pain (CPP): a systematic review. Physiother Theory Pract. 2019;35(6):516–32. Klotz SGR, Schön M, Ketels G, Löwe B, Brünahl CA. Physiotherapy management of patients with chronic pelvic pain (CPP): a systematic review. Physiother Theory Pract. 2019;35(6):516–32.
6.
Zurück zum Zitat Krieger JN, Lee SWH, Jeon J, Cheah PY, Liong ML, Riley DE. Epidemiology of prostatitis. Int J Antimicrob Agents. 2008;31(Suppl 1):S85–S90. PubMed Krieger JN, Lee SWH, Jeon J, Cheah PY, Liong ML, Riley DE. Epidemiology of prostatitis. Int J Antimicrob Agents. 2008;31(Suppl 1):S85–S90. PubMed
8.
Zurück zum Zitat Pastore EA, Katzman WB. Recognizing myofascial pelvic pain in the female patient with chronic pelvic pain. J Obstet Gynecol Neonatal Nurs. 2012;41(5):680–91. PubMedPubMedCentral Pastore EA, Katzman WB. Recognizing myofascial pelvic pain in the female patient with chronic pelvic pain. J Obstet Gynecol Neonatal Nurs. 2012;41(5):680–91. PubMedPubMedCentral
9.
Zurück zum Zitat Jarrell JF, Vilos GA, Allaire C, Burgess S, Fortin C, Gerwin R, et al. No. 164-consensus guidelines for the management of chronic pelvic pain. J Obstet Gynaecol Can. 2018;40(11):e747–87. PubMed Jarrell JF, Vilos GA, Allaire C, Burgess S, Fortin C, Gerwin R, et al. No. 164-consensus guidelines for the management of chronic pelvic pain. J Obstet Gynaecol Can. 2018;40(11):e747–87. PubMed
11.
Zurück zum Zitat Calhoun EA. The economic impact of chronic prostatitis. Arch Intern Med. 2004;164(11):1231. PubMed Calhoun EA. The economic impact of chronic prostatitis. Arch Intern Med. 2004;164(11):1231. PubMed
12.
Zurück zum Zitat Fuentes-Márquez P, Cabrera-Martos I, Valenza MC. Physiotherapy interventions for patients with chronic pelvic pain: a systematic review of the literature. Physiother Theory Pract. 2019;35(12):1131–8. PubMed Fuentes-Márquez P, Cabrera-Martos I, Valenza MC. Physiotherapy interventions for patients with chronic pelvic pain: a systematic review of the literature. Physiother Theory Pract. 2019;35(12):1131–8. PubMed
13.
Zurück zum Zitat Loving S, Nordling J, Jaszczak P, Thomsen T. Does evidence support physiotherapy management of adult female chronic pelvic pain? A systematic review. Scand J Pain. 2012;3(2):70–81. PubMed Loving S, Nordling J, Jaszczak P, Thomsen T. Does evidence support physiotherapy management of adult female chronic pelvic pain? A systematic review. Scand J Pain. 2012;3(2):70–81. PubMed
14.
Zurück zum Zitat Koh CE, Young CJ, Young JM, Solomon MJ. Systematic review of randomized controlled trials of the effectiveness of biofeedback for pelvic floor dysfunction. Br J Surg. 2008;95(9):1079–87. PubMed Koh CE, Young CJ, Young JM, Solomon MJ. Systematic review of randomized controlled trials of the effectiveness of biofeedback for pelvic floor dysfunction. Br J Surg. 2008;95(9):1079–87. PubMed
15.
Zurück zum Zitat Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gøtzsche PC, Ioannidis JPAA, et al. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. PLoS Med. 2009;6(7):e1000100. PubMedPubMedCentral Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gøtzsche PC, Ioannidis JPAA, et al. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. PLoS Med. 2009;6(7):e1000100. PubMedPubMedCentral
16.
Zurück zum Zitat Chiarioni G, Nardo A, Vantini I, Romito A, Whitehead WE. Biofeedback is superior to electrogalvanic stimulation and massage for treatment of levator ani syndrome. Gastroenterology. 2010;138(4):1321–9. PubMed Chiarioni G, Nardo A, Vantini I, Romito A, Whitehead WE. Biofeedback is superior to electrogalvanic stimulation and massage for treatment of levator ani syndrome. Gastroenterology. 2010;138(4):1321–9. PubMed
17.
Zurück zum Zitat Heah SM, Ho YH, Tan M, Leong AF. Biofeedback is effective treatment for levator ani syndrome. Dis Colon Rectum. 1997;40(2):187–9. PubMed Heah SM, Ho YH, Tan M, Leong AF. Biofeedback is effective treatment for levator ani syndrome. Dis Colon Rectum. 1997;40(2):187–9. PubMed
18.
Zurück zum Zitat Ger GC, Wexner SD, Jorge JMN, Lee E, Amaranath LA, Heymen S, et al. Evaluation and treatment of chronic intractable rectal pain – a frustrating endeavor. Dis Colon Rectum. 1993;36(2):139–45. PubMed Ger GC, Wexner SD, Jorge JMN, Lee E, Amaranath LA, Heymen S, et al. Evaluation and treatment of chronic intractable rectal pain – a frustrating endeavor. Dis Colon Rectum. 1993;36(2):139–45. PubMed
19.
Zurück zum Zitat Gilliland R, Heymen JS, Altomare DF, Vickers D, Wexner SD. Biofeedback for intractable rectal pain: outcome and predictors of success. Dis Colon Rectum. 1997a;40(2):190–6. PubMed Gilliland R, Heymen JS, Altomare DF, Vickers D, Wexner SD. Biofeedback for intractable rectal pain: outcome and predictors of success. Dis Colon Rectum. 1997a;40(2):190–6. PubMed
20.
Zurück zum Zitat Grimaud JC, Bouvier M, Naudy B, Guien C, Salducci J. Manometric and radiologic investigations and biofeedback treatment of chronic idiopathic anal pain. Dis Colon Rectum. 1991;34(8):690–5. PubMed Grimaud JC, Bouvier M, Naudy B, Guien C, Salducci J. Manometric and radiologic investigations and biofeedback treatment of chronic idiopathic anal pain. Dis Colon Rectum. 1991;34(8):690–5. PubMed
21.
Zurück zum Zitat Chiarioni G, Whitehead WE, Pezza V, Morelli A, Bassotti G. Biofeedback is superior to laxatives for normal transit constipation due to pelvic floor dyssynergia. Gastroenterology. 2006;130(3):657–64. PubMed Chiarioni G, Whitehead WE, Pezza V, Morelli A, Bassotti G. Biofeedback is superior to laxatives for normal transit constipation due to pelvic floor dyssynergia. Gastroenterology. 2006;130(3):657–64. PubMed
22.
Zurück zum Zitat Koutsomanis D, Lennard-Jones JE, Kamm MA. Prospective study of biofeedback treatment for patients with slow and normal transit constipation. Eur J Gastroenterol Hepatol. 1994;6(2):131–7. Koutsomanis D, Lennard-Jones JE, Kamm MA. Prospective study of biofeedback treatment for patients with slow and normal transit constipation. Eur J Gastroenterol Hepatol. 1994;6(2):131–7.
23.
Zurück zum Zitat Chiotakakou-Faliakou E, Kamm MA, Roy AJ, Storrie JB, Turner IC. Biofeedback provides long-term benefit for patients with intractable, slow and normal transit constipation. Gut. 1998;42(4):517–21. PubMed Chiotakakou-Faliakou E, Kamm MA, Roy AJ, Storrie JB, Turner IC. Biofeedback provides long-term benefit for patients with intractable, slow and normal transit constipation. Gut. 1998;42(4):517–21. PubMed
24.
Zurück zum Zitat Battaglia E, Serra AM, Buonafede G, Dughera L, Chistolini F, Morelli A, et al. Long-term study on the effects of visual biofeedback and muscle training as a  therapeutic modality in pelvic floor dyssynergia and slow-transit constipation. Dis Colon Rectum. 2004;47(1):90–5. PubMed Battaglia E, Serra AM, Buonafede G, Dughera L, Chistolini F, Morelli A, et al. Long-term study on the effects of visual biofeedback and muscle training as a  therapeutic modality in pelvic floor dyssynergia and slow-transit constipation. Dis Colon Rectum. 2004;47(1):90–5. PubMed
25.
Zurück zum Zitat Wang J, Luo M‑H, Qi Q‑H, Dong Z‑L. Prospective study of biofeedback retraining in patients with chronic idiopathic functional constipation. World J Gastroenterol. 2003;9(9):2109–13. PubMedPubMedCentral Wang J, Luo M‑H, Qi Q‑H, Dong Z‑L. Prospective study of biofeedback retraining in patients with chronic idiopathic functional constipation. World J Gastroenterol. 2003;9(9):2109–13. PubMedPubMedCentral
26.
Zurück zum Zitat Ba-Bai-Ke-Re M‑MT-JA, Wen N‑R, Hu Y‑L, Zhao L, Tuxun T, Husaiyin A, et al. Biofeedback-guided pelvic floor exercise therapy for obstructive defecation: an effective alternative. World J Gastroenterol. 2014;20(27):9162–9. PubMedPubMedCentral Ba-Bai-Ke-Re M‑MT-JA, Wen N‑R, Hu Y‑L, Zhao L, Tuxun T, Husaiyin A, et al. Biofeedback-guided pelvic floor exercise therapy for obstructive defecation: an effective alternative. World J Gastroenterol. 2014;20(27):9162–9. PubMedPubMedCentral
27.
Zurück zum Zitat Roy AJ, Emmanuel AV, Storrie JB, Bowers J, Kamm MA. Behavioural treatment (biofeedback) for constipation following hysterectomy. Br J Surg. 2000;87(1):100–5. PubMed Roy AJ, Emmanuel AV, Storrie JB, Bowers J, Kamm MA. Behavioural treatment (biofeedback) for constipation following hysterectomy. Br J Surg. 2000;87(1):100–5. PubMed
28.
Zurück zum Zitat Chiarioni G, Salandini L, Whitehead WE. Biofeedback benefits only patients with outlet dysfunction, not patients with isolated slow transit constipation. Gastroenterology. 2005;129(1):86–97. PubMed Chiarioni G, Salandini L, Whitehead WE. Biofeedback benefits only patients with outlet dysfunction, not patients with isolated slow transit constipation. Gastroenterology. 2005;129(1):86–97. PubMed
29.
Zurück zum Zitat Zhu F‑F, Lin Z, Lin L, Wang M‑F. Changes in quality of life during biofeedback for people with puborectalis dyssynergia: generic and disease-specific measures. J Adv Nurs. 2011;67(6):1285–93. PubMed Zhu F‑F, Lin Z, Lin L, Wang M‑F. Changes in quality of life during biofeedback for people with puborectalis dyssynergia: generic and disease-specific measures. J Adv Nurs. 2011;67(6):1285–93. PubMed
30.
Zurück zum Zitat Gilliland R, Heymen S, Altomare DF, Park UC, Vickers D, Wexner SD. Outcome and predictors of success of biofeedback for constipation. Br J Surg. 1997b;84(8):1123–6. PubMed Gilliland R, Heymen S, Altomare DF, Park UC, Vickers D, Wexner SD. Outcome and predictors of success of biofeedback for constipation. Br J Surg. 1997b;84(8):1123–6. PubMed
31.
Zurück zum Zitat Parker CH, Henry S, Liu LWC. Efficacy of biofeedback therapy in clinical practice for the management of chronic constipation and fecal incontinence. J Can Assoc Gastroenterol. 2019;2(3):126–31. PubMed Parker CH, Henry S, Liu LWC. Efficacy of biofeedback therapy in clinical practice for the management of chronic constipation and fecal incontinence. J Can Assoc Gastroenterol. 2019;2(3):126–31. PubMed
32.
Zurück zum Zitat Clemens JQ, Nadler RB, Schaeffer AJ, Belani J, Albaugh J, Bushman W. Biofeedback, pelvic floor re-education, and bladder training for male chronic pelvic pain syndrome. Urology. 2000;56(6):951–5. PubMed Clemens JQ, Nadler RB, Schaeffer AJ, Belani J, Albaugh J, Bushman W. Biofeedback, pelvic floor re-education, and bladder training for male chronic pelvic pain syndrome. Urology. 2000;56(6):951–5. PubMed
34.
Zurück zum Zitat Cornel EB, Van Haarst EP, Browning-Groote Schaarsberg RWM, Geels J, Schaarsberg RWMB‑G, Geels J. The effect of biofeedback physical therapy in men with chronic pelvic pain syndrome type III. Eur Urol. 2005;47(5):607–11. PubMed Cornel EB, Van Haarst EP, Browning-Groote Schaarsberg RWM, Geels J, Schaarsberg RWMB‑G, Geels J. The effect of biofeedback physical therapy in men with chronic pelvic pain syndrome type III. Eur Urol. 2005;47(5):607–11. PubMed
35.
Zurück zum Zitat Yang MH, Huang YH, Lai YF, Zeng SW, Chen SL. Comparing electromagnetic stimulation with electrostimulation plus biofeedback in treating male refractory chronic pelvic pain syndrome. Urol Sci. 2017;28(3):156–61. Yang MH, Huang YH, Lai YF, Zeng SW, Chen SL. Comparing electromagnetic stimulation with electrostimulation plus biofeedback in treating male refractory chronic pelvic pain syndrome. Urol Sci. 2017;28(3):156–61.
36.
Zurück zum Zitat He W, Chen M, Zu X, Li Y, Ning K, Qi L. Chronic prostatitis presenting with dysfunctional voiding and effects of pelvic floor biofeedback treatment. BJU Int. 2010;105(7):975–7. PubMed He W, Chen M, Zu X, Li Y, Ning K, Qi L. Chronic prostatitis presenting with dysfunctional voiding and effects of pelvic floor biofeedback treatment. BJU Int. 2010;105(7):975–7. PubMed
37.
Zurück zum Zitat Schmitt JJ, Singh R, Weaver AL, Mara KC, Harvey-Springer RR, Fick FR, et al. Prospective outcomes of a pelvic floor rehabilitation program including vaginal electrogalvanic stimulation for urinary, defecatory, and pelvic pain symptoms. Female Pelvic Med Reconstr Surg. 2017;23(2):108–13. PubMedPubMedCentral Schmitt JJ, Singh R, Weaver AL, Mara KC, Harvey-Springer RR, Fick FR, et al. Prospective outcomes of a pelvic floor rehabilitation program including vaginal electrogalvanic stimulation for urinary, defecatory, and pelvic pain symptoms. Female Pelvic Med Reconstr Surg. 2017;23(2):108–13. PubMedPubMedCentral
38.
Zurück zum Zitat Glazer HI, Rodke G, Swencionis C, Hertz R, Young AW. Treatment of vulvar vestibulitis syndrome with electromyographic biofeedback of pelvic floor musculature. J Reprod Med. 1995;40(4):283–90. PubMed Glazer HI, Rodke G, Swencionis C, Hertz R, Young AW. Treatment of vulvar vestibulitis syndrome with electromyographic biofeedback of pelvic floor musculature. J Reprod Med. 1995;40(4):283–90. PubMed
39.
Zurück zum Zitat McKay E, Kaufman RH, Doctor U, Berkova Z, Glazer H, Redko V. Treating vulvar vestibulitis with electromyographic biofeedback of pelvic floor musculature. J Reprod Med. 2001;46(4):337–42. PubMed McKay E, Kaufman RH, Doctor U, Berkova Z, Glazer H, Redko V. Treating vulvar vestibulitis with electromyographic biofeedback of pelvic floor musculature. J Reprod Med. 2001;46(4):337–42. PubMed
40.
Zurück zum Zitat Gentilcore-Saulnier E, McLean L, Goldfinger C, Pukall CF, Chamberlain S. Pelvic floor muscle assessment outcomes in women with and without provoked vestibulodynia and the impact of a physical therapy program. J Sex Med. 2010;7(2 PART 2):1003–22. PubMed Gentilcore-Saulnier E, McLean L, Goldfinger C, Pukall CF, Chamberlain S. Pelvic floor muscle assessment outcomes in women with and without provoked vestibulodynia and the impact of a physical therapy program. J Sex Med. 2010;7(2 PART 2):1003–22. PubMed
41.
Zurück zum Zitat Bendaña EE, Belarmino JM, Dinh JH, Cook CL, Murray BP, Feustel PJ, et al. Efficacy of transvaginal biofeedback and electrical stimulation in women with urinary urgency and frequency and associated pelvic floor muscle spasm. Urol Nurs. 2009;29(3):171–6. PubMed Bendaña EE, Belarmino JM, Dinh JH, Cook CL, Murray BP, Feustel PJ, et al. Efficacy of transvaginal biofeedback and electrical stimulation in women with urinary urgency and frequency and associated pelvic floor muscle spasm. Urol Nurs. 2009;29(3):171–6. PubMed
42.
Zurück zum Zitat Philips HC, Fenster HN, Samsom D. An effective treatment for functional urinary incoordination. J Behav Med. 1992;15(1):45–63. PubMed Philips HC, Fenster HN, Samsom D. An effective treatment for functional urinary incoordination. J Behav Med. 1992;15(1):45–63. PubMed
43.
Zurück zum Zitat Hart AD, Mathisen KS, Prater JS. A comparison of skin temperature and EMG training for primary dysmenorrhea. Biofeedback Self Regul. 1981;6(3):367–73. PubMed Hart AD, Mathisen KS, Prater JS. A comparison of skin temperature and EMG training for primary dysmenorrhea. Biofeedback Self Regul. 1981;6(3):367–73. PubMed
44.
Zurück zum Zitat Bennink CD, Hulst LL, Benthem JA. The effects of EMG biofeedback and relaxation training on primary dysmenorrhea. J Behav Med. 1982;5(3):329–41. PubMed Bennink CD, Hulst LL, Benthem JA. The effects of EMG biofeedback and relaxation training on primary dysmenorrhea. J Behav Med. 1982;5(3):329–41. PubMed
45.
Zurück zum Zitat Vagedes J, Fazeli A, Boening A, Helmert E, Berger B, Martin D. Efficacy of rhythmical massage in comparison to heart rate variability biofeedback in patients with dysmenorrhea—A randomized, controlled trial. Complement Ther Med. 2019;42:438–44. PubMed Vagedes J, Fazeli A, Boening A, Helmert E, Berger B, Martin D. Efficacy of rhythmical massage in comparison to heart rate variability biofeedback in patients with dysmenorrhea—A randomized, controlled trial. Complement Ther Med. 2019;42:438–44. PubMed
46.
Zurück zum Zitat Starr JA, Drobnis EZ, Lenger S, Parrot J, Barrier B, Foster R. Outcomes of a comprehensive nonsurgical approach to pelvic floor rehabilitation for urinary symptoms, defecatory dysfunction, and pelvic pain. Female Pelvic Med Reconstr Surg. 2013;19(5):260–5. PubMed Starr JA, Drobnis EZ, Lenger S, Parrot J, Barrier B, Foster R. Outcomes of a comprehensive nonsurgical approach to pelvic floor rehabilitation for urinary symptoms, defecatory dysfunction, and pelvic pain. Female Pelvic Med Reconstr Surg. 2013;19(5):260–5. PubMed
47.
Zurück zum Zitat Lúcio AC, D’Ancona CAL, Lopes MHBM, Perissinotto MC, Damasceno BP, Ancona CALD, et al. The effect of pelvic floor muscle training alone or in combination with electrostimulation in the treatment of sexual dysfunction in women with multiple sclerosis. Mult Scler J. 2014;20(13):1761–8. Lúcio AC, D’Ancona CAL, Lopes MHBM, Perissinotto MC, Damasceno BP, Ancona CALD, et al. The effect of pelvic floor muscle training alone or in combination with electrostimulation in the treatment of sexual dysfunction in women with multiple sclerosis. Mult Scler J. 2014;20(13):1761–8.
50.
Zurück zum Zitat Pacik PT, Geletta S. Vaginismus treatment: clinical trials follow up 241 patients. Sex Med. 2017;5(2):e114–e23. PubMedPubMedCentral Pacik PT, Geletta S. Vaginismus treatment: clinical trials follow up 241 patients. Sex Med. 2017;5(2):e114–e23. PubMedPubMedCentral
51.
Zurück zum Zitat Hoebeke P, Van Laecke E, Renson C, Raes A, Dehoorne J, Vermeiren P, et al. Pelvic floor spasms in children: an unknown condition responding well to pelvic floor therapy. Eur Urol. 2004;46(5):651–4. PubMed Hoebeke P, Van Laecke E, Renson C, Raes A, Dehoorne J, Vermeiren P, et al. Pelvic floor spasms in children: an unknown condition responding well to pelvic floor therapy. Eur Urol. 2004;46(5):651–4. PubMed
52.
Zurück zum Zitat Ebiloglu T, Kaya E, Köprü B, Topuz B, Irkilata HC, Kibar Y. Biofeedback as a first-line treatment for overactive bladder syndrome refractory to standard urotherapy in children. J Pediatr Urol. 2016;12(5):290.e1–290.e7. Ebiloglu T, Kaya E, Köprü B, Topuz B, Irkilata HC, Kibar Y. Biofeedback as a first-line treatment for overactive bladder syndrome refractory to standard urotherapy in children. J Pediatr Urol. 2016;12(5):290.e1–290.e7.
53.
Zurück zum Zitat Ergin G, Kibar Y, Ebiloǧlu T, Irkilata HC, Kopru B, Kaya E, et al. The role of urinary nerve growth factor for the diagnosis and assessment of the biofeedback success in children with dysfunctional voiding. J Pediatr Urol. 2016;12(2):118.e1–118.e6. Ergin G, Kibar Y, Ebiloǧlu T, Irkilata HC, Kopru B, Kaya E, et al. The role of urinary nerve growth factor for the diagnosis and assessment of the biofeedback success in children with dysfunctional voiding. J Pediatr Urol. 2016;12(2):118.e1–118.e6.
54.
Zurück zum Zitat Li Y, Qi L, Wen JG, Zu XB, Chen ZY. Chronic prostatitis during puberty. BJU Int. 2006;98(4):818–21. PubMed Li Y, Qi L, Wen JG, Zu XB, Chen ZY. Chronic prostatitis during puberty. BJU Int. 2006;98(4):818–21. PubMed
55.
Zurück zum Zitat Kent P, Laird R, Haines T. The effect of changing movement and posture using motion-sensor biofeedback, versus guidelines-based care, on the clinical outcomes of people with sub-acute or chronic low back pain‑a multicentre, cluster-randomised, placebo-controlled, pilot trial. BMC Musculoskelet Disord. 2015. https://​doi.​org/​10.​1186/​s12891-015-0591-5. Kent P, Laird R, Haines T. The effect of changing movement and posture using motion-sensor biofeedback, versus guidelines-based care, on the clinical outcomes of people with sub-acute or chronic low back pain‑a multicentre, cluster-randomised, placebo-controlled, pilot trial. BMC Musculoskelet Disord. 2015. https://​doi.​org/​10.​1186/​s12891-015-0591-5.
57.
Zurück zum Zitat Akbal C, Şahan A, Şener TE, Şahin B, Tinay I, Tarcan T, et al. Diagnostic value of the pediatric lower urinary tract symptom score in children with overactive bladder. World J Urol. 2014;32(1):201–8. PubMed Akbal C, Şahan A, Şener TE, Şahin B, Tinay I, Tarcan T, et al. Diagnostic value of the pediatric lower urinary tract symptom score in children with overactive bladder. World J Urol. 2014;32(1):201–8. PubMed
60.
Zurück zum Zitat Karcioglu O, Topacoglu H, Dikme O, Dikme O. A systematic review of the pain scales in adults: which to use? Am J Emerg Med. 2018;36(4):707–14. PubMed Karcioglu O, Topacoglu H, Dikme O, Dikme O. A systematic review of the pain scales in adults: which to use? Am J Emerg Med. 2018;36(4):707–14. PubMed
61.
Zurück zum Zitat Cohen J. Statistical power analsis of the behavioral sciences. New Jersey: Lawrence Earlbaum; 1988. Cohen J. Statistical power analsis of the behavioral sciences. New Jersey: Lawrence Earlbaum; 1988.
62.
Zurück zum Zitat Agachan F, Chen T, Pfeifer J, Reissman P, Wexner SD. A constipation scoring system to simplify evaluation and management of constipated patients. Dis Colon Rectum. 1996;39(6):681–5. PubMed Agachan F, Chen T, Pfeifer J, Reissman P, Wexner SD. A constipation scoring system to simplify evaluation and management of constipated patients. Dis Colon Rectum. 1996;39(6):681–5. PubMed
64.
Zurück zum Zitat Akbal C, Genc Y, Burgu B, Ozden E, Tekgul S. Dysfunctional voiding and incontinence scoring system: Quantitative evaluation of incontinence symptoms in pediatric population. J Urol. 2005;173(3):969–73. PubMed Akbal C, Genc Y, Burgu B, Ozden E, Tekgul S. Dysfunctional voiding and incontinence scoring system: Quantitative evaluation of incontinence symptoms in pediatric population. J Urol. 2005;173(3):969–73. PubMed
65.
Zurück zum Zitat Selekman RE, Harris CR, Filippou P, Chi T, Alwaal A, Blaschko SD, et al. Validation of a visual prostate symptom score in men with lower urinary tract symptoms in a health safety net hospital. Urology. 2015;86(2):354–8. PubMed Selekman RE, Harris CR, Filippou P, Chi T, Alwaal A, Blaschko SD, et al. Validation of a visual prostate symptom score in men with lower urinary tract symptoms in a health safety net hospital. Urology. 2015;86(2):354–8. PubMed
66.
Zurück zum Zitat Clemens JQ, Calhoun EA, Litwin MS, McNaughton-Collins M, Dunn RL, Crowley EM, et al. Rescoring the NIH chronic prostatitis symptom index: nothing new. Prostate Cancer Prostatic Dis. 2009;12(3):285–7. PubMedPubMedCentral Clemens JQ, Calhoun EA, Litwin MS, McNaughton-Collins M, Dunn RL, Crowley EM, et al. Rescoring the NIH chronic prostatitis symptom index: nothing new. Prostate Cancer Prostatic Dis. 2009;12(3):285–7. PubMedPubMedCentral
67.
Zurück zum Zitat Ware JE, Sherbourne CD. The MOS 36-item short-form health survey (Sf-36): I. conceptual framework and item selection. Med Care. 1992;30(6):473–83. Ware JE, Sherbourne CD. The MOS 36-item short-form health survey (Sf-36): I. conceptual framework and item selection. Med Care. 1992;30(6):473–83.
68.
Zurück zum Zitat Resnick B, Parker R. Simplified scoring and psychometrics of the revised 12-item short-form health survey. Outcomes Manag Nurs Pract. 2001;5(4):161–6. Resnick B, Parker R. Simplified scoring and psychometrics of the revised 12-item short-form health survey. Outcomes Manag Nurs Pract. 2001;5(4):161–6.
69.
Zurück zum Zitat Laycock J, Jerwood D. Pelvic floor muscle assessment: the PERFECT scheme. Physiotherapy. 2001;87(12):631–42. Laycock J, Jerwood D. Pelvic floor muscle assessment: the PERFECT scheme. Physiotherapy. 2001;87(12):631–42.
70.
Zurück zum Zitat Gonnermann A, Framke T, Großhennig A, Koch A. No solution yet for combining two independent studies in the presence of heterogeneity. Stat Med. 2015;34(16):2476–80. PubMedPubMedCentral Gonnermann A, Framke T, Großhennig A, Koch A. No solution yet for combining two independent studies in the presence of heterogeneity. Stat Med. 2015;34(16):2476–80. PubMedPubMedCentral
74.
Zurück zum Zitat Briggs AM, Smith AJ, Straker LM, Bragge P. Thoracic spine pain in the general population: prevalence, incidence and associated factors in children, adolescents and adults. A systematic review. BMC Musculoskelet Disord. 2009;10(1):77. PubMedPubMedCentral Briggs AM, Smith AJ, Straker LM, Bragge P. Thoracic spine pain in the general population: prevalence, incidence and associated factors in children, adolescents and adults. A systematic review. BMC Musculoskelet Disord. 2009;10(1):77. PubMedPubMedCentral
75.
Zurück zum Zitat Daly AE, Bialocerkowski AE. Does evidence support physiotherapy management of adult Complex Regional Pain Syndrome Type One? A systematic review. Eur J Pain. 2009;13(4):339–53. PubMed Daly AE, Bialocerkowski AE. Does evidence support physiotherapy management of adult Complex Regional Pain Syndrome Type One? A systematic review. Eur J Pain. 2009;13(4):339–53. PubMed
76.
Zurück zum Zitat Maher CG, Sherrington C, Herbert RD, Moseley AM, Elkins M. Reliability of the PEDro scale for rating quality of randomized controlled trials. Phys Ther. 2003;83(8):713–21. PubMed Maher CG, Sherrington C, Herbert RD, Moseley AM, Elkins M. Reliability of the PEDro scale for rating quality of randomized controlled trials. Phys Ther. 2003;83(8):713–21. PubMed
77.
Zurück zum Zitat De Morton NA. The PEDro scale is a valid measure of the methodological quality of clinical trials: a demographic study. Aust J Physiother. 2009;55(2):129–33. PubMed De Morton NA. The PEDro scale is a valid measure of the methodological quality of clinical trials: a demographic study. Aust J Physiother. 2009;55(2):129–33. PubMed
78.
Zurück zum Zitat Bhogal SK, Teasell RW, Foley NC, Speechley MR. The PEDro scale provides a more comprehensive measure of methodological quality than the Jadad scale in stroke rehabilitation literature. J Clin Epidemiol. 2005;58(7):668–73. PubMed Bhogal SK, Teasell RW, Foley NC, Speechley MR. The PEDro scale provides a more comprehensive measure of methodological quality than the Jadad scale in stroke rehabilitation literature. J Clin Epidemiol. 2005;58(7):668–73. PubMed
79.
Zurück zum Zitat Yamato TP, Maher C, Koes B, Moseley A. The PEDro scale had acceptably high convergent validity, construct validity, and interrater reliability in evaluating methodological quality of pharmaceutical trials. J Clin Epidemiol. 2017;86:176–181 Yamato TP, Maher C, Koes B, Moseley A. The PEDro scale had acceptably high convergent validity, construct validity, and interrater reliability in evaluating methodological quality of pharmaceutical trials. J Clin Epidemiol. 2017;86:176–181
80.
Zurück zum Zitat Cashin AG, McAuley JH. Clinimetrics: physiotherapy evidence database (PEDro) scale. J Physiother. 2020;66:59. PubMed Cashin AG, McAuley JH. Clinimetrics: physiotherapy evidence database (PEDro) scale. J Physiother. 2020;66:59. PubMed
83.
Zurück zum Zitat Rao SSC, Benninga MA, Bharucha AE, Chiarioni G, Di Lorenzo C, Whitehead WE. ANMS-ESNM position paper and consensus guidelines on biofeedback therapy for anorectal disorders. Neurogastroenterol Motil. 2015;27(5):594–609. PubMedPubMedCentral Rao SSC, Benninga MA, Bharucha AE, Chiarioni G, Di Lorenzo C, Whitehead WE. ANMS-ESNM position paper and consensus guidelines on biofeedback therapy for anorectal disorders. Neurogastroenterol Motil. 2015;27(5):594–609. PubMedPubMedCentral
86.
Zurück zum Zitat Narayanan SP, Bharucha AE. A practical guide to biofeedback therapy for pelvic floor disorders. Curr Gastroenterol Rep. 2019;21(5):21. PubMed Narayanan SP, Bharucha AE. A practical guide to biofeedback therapy for pelvic floor disorders. Curr Gastroenterol Rep. 2019;21(5):21. PubMed
88.
Zurück zum Zitat Heymen S, Scarlett Y, Jones K, Ringel Y, Drossman D, Whitehead WE. Randomized, controlled trial shows biofeedback to be superior to alternative treatments for patients with pelvic floor dyssynergia-type constipation. Dis Colon Rectum. 2007;50(4):428–41. PubMed Heymen S, Scarlett Y, Jones K, Ringel Y, Drossman D, Whitehead WE. Randomized, controlled trial shows biofeedback to be superior to alternative treatments for patients with pelvic floor dyssynergia-type constipation. Dis Colon Rectum. 2007;50(4):428–41. PubMed
89.
Zurück zum Zitat Mariani L. Vulvar vestibulitis syndrome: an overview of non-surgical treatment. Eur J Obstet Gynecol Reprod Biol. 2002;101(2):109–12. PubMed Mariani L. Vulvar vestibulitis syndrome: an overview of non-surgical treatment. Eur J Obstet Gynecol Reprod Biol. 2002;101(2):109–12. PubMed
90.
Zurück zum Zitat Morin M, Carroll M‑SS, Bergeron S. Systematic review of the effectiveness of physical therapy modalities in women with provoked vestibulodynia. Sex Med Rev. 2017;5(3):295–322. PubMed Morin M, Carroll M‑SS, Bergeron S. Systematic review of the effectiveness of physical therapy modalities in women with provoked vestibulodynia. Sex Med Rev. 2017;5(3):295–322. PubMed
91.
Zurück zum Zitat Bergeron S, Binik YM, Khalifé S, Pagidas K, Glazer HI, Meana M, et al. A randomized comparison of group cognitive-behavioral therapy, surface electromyographic biofeedback, and vestibulectomy in the treatment of dyspareunia resulting from vulvar vestibulitis. Pain. 2001;91(3):297–306. PubMed Bergeron S, Binik YM, Khalifé S, Pagidas K, Glazer HI, Meana M, et al. A randomized comparison of group cognitive-behavioral therapy, surface electromyographic biofeedback, and vestibulectomy in the treatment of dyspareunia resulting from vulvar vestibulitis. Pain. 2001;91(3):297–306. PubMed
92.
Zurück zum Zitat Shoskes DA, Nickel JC, Rackley RR, Pontari MA. Clinical phenotyping in chronic prostatitis/chronic pelvic pain syndrome and interstitial cystitis: a management strategy for urologic chronic pelvic pain syndromes. Prostate Cancer Prostatic Dis. 2009;12(2):177–83. PubMed Shoskes DA, Nickel JC, Rackley RR, Pontari MA. Clinical phenotyping in chronic prostatitis/chronic pelvic pain syndrome and interstitial cystitis: a management strategy for urologic chronic pelvic pain syndromes. Prostate Cancer Prostatic Dis. 2009;12(2):177–83. PubMed
94.
Zurück zum Zitat Fall M, Baranowski AP, Elneil S, Engeler D, Hughes J, Messelink EJ, et al. EAU guidelines on chronic pelvic pain. Eur Urol. 2010;57(1):35–48. PubMed Fall M, Baranowski AP, Elneil S, Engeler D, Hughes J, Messelink EJ, et al. EAU guidelines on chronic pelvic pain. Eur Urol. 2010;57(1):35–48. PubMed
Metadaten
Titel
The effect of biofeedback interventions on pain, overall symptoms, quality of life and physiological parameters in patients with pelvic pain
A systematic review
verfasst von
Dr. Barbara Wagner
Mag. Margarete Steiner
Dr. Dominikus Franz Xaver Huber
MBA MMSc Univ. Prof. Dr. Richard Crevenna
Publikationsdatum
22.03.2021
Verlag
Springer Vienna
Erschienen in
Wiener klinische Wochenschrift / Ausgabe Sonderheft 1/2022
Print ISSN: 0043-5325
Elektronische ISSN: 1613-7671
DOI
https://doi.org/10.1007/s00508-021-01827-w