Benefits and Harms of Electrical Neuromodulation for Chronic Pelvic Pain: A Systematic Review

Effect of different electric stimulation modalities on pain and functionality of patients with pelvic pain: Systematic review with META-analysis

INTRODUCTION

Pelvic pain is located in the anterior abdominal wall, below the umbilical scar. Its treatment includes pharmacological therapy, which can cause adverse effects and is not always sufficient to control symptoms. Thus, the use of adjunct therapies such as electric stimulation has been suggested. Therefore, this review intends to appraise the literature on the effectiveness of electrostimulation in the treatment of pelvic pain.

METHODS

The search for studies was conducted until April 2024 in PubMed, Cochrane Library, ScienceDirect, SciELO, PEDro, CINAHL, BVS, Web of Science, Scopus, and Google Scholar databases using a combination of Mesh terms "Electric Stimulation" and "Pelvic Pain." Risk of bias assessment and meta-analysis were performed with The Cochrane Collaboration tool (RevMan 5.4). Quality of the evidence was assessed with GRADE tool.

RESULTS

From the 3247 studies found, 19 were included. In the qualitative analysis, seven studies showed TENS, electroacupuncture, PTNS, and tDCS reduced pain intensity, one study on PTNS showed increased quality of life, and one on tDCS showed improved functional performance. However, in the meta-analysis, only TENS showed efficacy for the reduction of acute pelvic pain and primary dysmenorrhea.

CONCLUSION

Our results indicate that there is moderate-quality evidence for TENS to reduce pain intensity in primary dysmenorrhea and low-quality evidence for the same outcome in acute pelvic pain. Randomized controlled clinical trials with larger sample size and with better methodological quality are needed to establish the effectiveness of other forms of electrical stimulation in pelvic pain.

Effectiveness of nonpharmacological conservative therapies for chronic pelvic pain in women: a systematic review and meta-analysis

OBJECTIVE

To evaluate the effectiveness of nonpharmacological conservative therapies for women with CPP.

DATA SOURCES

A systematic search of electronic databases (Amed, CINAHL, PsycINFO, SportDiscuss, Medline, PubMed, Embase, and Cochrane Central Register of Controlled Trials) was performed in January 2023, and updated in December 2023.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials comparing a nonpharmacological conservative therapy to inert (eg, placebo, usual care) or nonconservative (eg, surgical, pharmacological) treatment were included. Conservative therapies of interest to this review were: multimodal physical therapy, predominantly psychological approaches, acupuncture, and other tissue-based monotherapies (eg, electrophysical agents, manual stretching).

STUDY APPRAISAL AND SYNTHESIS METHODS

All study data were aggregated, and analyses of the included studies were performed. Effects on pain; sexual measures; psychological and physical function; health-related quality of life; symptom severity/bother; pelvic floor muscle function and morphometry; perceived improvement; and adverse events were analyzed. Meta-analyses (random effects model) were conducted using postintervention scores for data that included similar interventions and outcomes. Standardized mean differences were calculated. A narrative summary of findings that could not be included in the meta-analysis is provided. The quality of the evidence was assessed with the Physiotherapy Evidence Database scale and the certainty of evidence with Grading of Recommendations, Assessment, Development, and Evaluations criteria.

RESULTS

Of 5776 retrieved studies, 38 randomized controlled trials including 2168 women (mean age 35.1±8.6) were included. Meta-analyses revealed that multimodal physical therapy resulted in lower pain intensity compared to inert or nonconservative treatments in both the short (standardized mean difference -1.69, 95% confidence interval -2.54, -0.85; high certainty) and intermediate-terms (standardized mean difference -1.82, 95% confidence interval -3.13, -0.52; moderate certainty), while predominantly psychological approaches resulted in no difference in pain intensity (standardized mean difference -0.18, 95% confidence interval -0.56, 0.20; moderate certainty) and a slight difference in sexual function (standardized mean difference -0.28, 95% confidence interval -0.52, -0.04; moderate certainty). The level of evidence regarding the meta-analysis of the effects of acupuncture on pain intensity (standardized mean difference 1.08, 95% confidence interval -1.38, 3.54, nonstatistically significant results in favor of control treatment) precluded any statement of certainty. A limited number of trials investigated individual tissue-based monotherapies, providing a restricted body of evidence.

CONCLUSION

This systematic review with meta-analysis revealed that multimodal physical therapy is effective in women with chronic pelvic pain with a high certainty of evidence.

Chronic Primary Pelvic Pain Syndrome in Men

BACKGROUND

Chronic primary pelvic pain syndrome in men (CPPPSm) can be associated with urogenital pain, urinary symptoms, sexual dysfunction, and emotional disturbance. Its clinical heterogeneity and incompletely understood pathogenesis make it more difficult to treat. This article is intended to familiarize the reader with basic aspects of the manifestations, pathophysiology, diagnostic evaluation, differential diagnosis, and treatment of this condition.

METHODS

This article is based on relevant publications retrieved by a selective search of the literature, including the current guidelines of the European Association of Urology. The features of this disease pertaining to urology, psychosomatic medicine, and pain medicine are illuminated from an interdisciplinary perspective.

RESULTS

Chronic pelvic pain appears to arise through a complex interaction of inflammatory, infectious, neurological, musculoskeletal, and psychosomatic factors. A comprehensive diagnostic work-up should be carried out to evaluate and exclude the numerous differential diagnoses. Treatment strategies are based on the clinical phenotype. Randomized controlled trials have shown that significant relief can be achieved with a variety of drugs and non-pharmacological treatments, selected according to the manifestations of the condition in the individual case. Attention must be paid to treatment-specific adverse effects.

CONCLUSION

The management of patients with CPPPSm should consist of a comprehensive differential diagnostic evaluation and an individually oriented treatment strategy.

Sacral neuromodulation in the management of chronic pelvic pain: A systematic review and meta-analysis

INTRODUCTION

Sacral neuromodulation (SNM) is a treatment approved for use in several conditions including refractory overactive bladder (OAB) and voiding dysfunction. Chronic pelvic pain (CPP) is a debilitating condition for which treatment is often challenging. SNM shows promising effect in patients with refractory CPP. However, there is a lack of clear evidence, especially in long-term outcomes. This systematic review will assess outcomes of SNM for treating CPP.

METHODS

A systematic search of MEDLINE, Embase, Cochrane Central and clinical trial databases was completed from database inception until January 14, 2022. Studies using original data investigating SNM in an adult population with CPP which recorded pre and posttreatment pain scores were selected. Primary outcome was numerical change in pain score. Secondary outcomes were quality of life assessment and change in medication use and all-time complications of SNM. Risk of bias was assessed using the Newcastle Ottawa Tool for cohort studies.

RESULTS

Twenty-six of 1026 identified articles were selected evaluating 853 patients with CPP. The implantation rate after test-phase success was 64.3%. Significant improvement of pain scores was reported in 13 studies; three studies reported no significant change. WMD in pain scores on a 10-point scale was -4.64 (95% confidence interval [CI] = -5.32 to -3.95, p < 0.00001) across 20 studies which were quantitatively synthesized: effects were maintained at long-term follow-up. Mean follow-up was 42.5 months (0-59). Quality of life was measured by RAND SF-36 and EQ-5D questionnaires and all studies reported improvement in quality of life. One hundred and eighty-nine complications were reported in 1555 patients (Clavien-Dindo Grade I-IIIb). Risk of bias ranged from low to high risk. Studies were case series and bias stemmed from selection bias and loss to follow-up.

CONCLUSION

Sacral Neuromodulation is a reasonably effective treatment of Chronic Pelvic Pain and significantly reduces pain and increases patients' quality of life with immediate to long-term effects.

Comparison of transcutaneous tibial nerve stimulation versus percutaneous tibial nerve stimulation in category IIIB chronic prostatitis/chronic pelvic pain syndrome: A randomized prospective trial

BACKGROUND

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a heterogenous condition that impacts the Quality of life severely, and it has multimodal complex treatment options. We aimed to compare the efficacy of two well-described neuromodulation therapies, transcutaneous tibial nerve stimulation (TTNS) versus percutaneous tibial nerve stimulation (PTNS) in the treatment of category IIIB CP/CPPS.

METHODS

This study was designed as a randomized prospective clinical trial. We randomized category IIIB CP/CPPS patients into two treatment groups as TTNS and PTNS groups. Category IIIB CP/CPPS was diagnosed by two or four-glass Meares-Stamey test. All patients included in our study were antibiotic/anti-inflammatory resistant. Transcutaneous and percutaneous treatments were applied 30 min sessions for 12 weeks. Patients were evaluated by Turkish-validated National Health Institute Chronic Prostatitis Symptom Index (NIH-CPSI) and visual analogue scale (VAS) initially and after treatment. Treatment success was evaluated within each group and also compared with each other.

RESULTS

A total of 38 patients in the TTNS group and 42 patients in the PTNS group were included in the final analysis. The mean VAS scores of the TTNS group were lower than the PTNS group initially (7.11 and 7.43, respectively), (p = 0.03). The pretreatment NIH-CPSI scores were similar between groups (p = 0.07). VAS scores, total NIH-CPSI, NIH-CPSI micturation, NIH-CPSI pain, and NIH-CPSI QoL scores decreased significantly at the end of the treatment in both groups. We found a significantly higher VAS and NIH-CPSI scores decrease in the PTNS group compared to the TTNS group (p < 0.01).

CONCLUSION

Both PTNS and TTNS are effective treatment methods in category IIIB CP/CPPS. Comparing the two methods, PTNS provided a higher level of improvement in terms of pain and quality of life.

Transcutaneous electrical nerve stimulation for pelvic pain: A scoping review of treatment protocols, practical indications, and caveats

BACKGROUND

Neuromodulation (NM) is a family of therapies based on electrical stimulation to target specific nerves that control LUTS (Lower Urinary Tract Symptoms) and pain. The aim is to modulate what is happening within the nervous system to achieve therapeutic effects. A particular type of neuromodulation, called TENS (Transcutaneous Electrical Nerve Stimulation), has proven effective for treating pelvic pain. The available evidence provides indications regarding the many aspects of TENS that influence therapeutic effects, but a comprehensive review has yet to be conducted.

METHODS

Scoping review on Pubmed, CINAHL, Embase, Scopus, and Web of Science, including clinical trials, reviews, case studies or series, and other descriptive studies, according to the Joanna Briggs and PRISMA methodology.

RESULTS

The 31 papers retrieved allowed the formulation of precise indications about the DOs and DON'Ts of electrode placement, waveform, pulse duration, pulse frequency, amplitude, session duration, and frequency of sessions. This paper also discusses the biochemical and neuro urological mechanisms of TENS.

CONCLUSION

TENS effectiveness is influenced by many factors, some self-evident, others subtle, which this paper elucidates. Pelvic pain requires a multimodal approach, of which TENS is just a part. TENS should therefore be viewed as one of the components of the rehabilitation program in the frame of thorough and continuous patient assessment.

Effect of high-frequency repetitive transcranial magnetic stimulation under different intensities upon rehabilitation of chronic pelvic pain syndrome: protocol for a randomized controlled trial

INTRODUCTION

Nearly one in seven women worldwide suffers from chronic pelvic pain syndrome (CPPS) each year. Often, CPPS necessitates a combination of treatments. Studies have shown the good therapeutic effects of repetitive transcranial magnetic stimulation (rTMS) upon CPPS. We wish to undertake a randomized controlled trial (RCT) to observe the effect of high-frequency rTMS at different intensities upon CPPS.

METHODS AND ANALYSES

In this prospective, double-blinded RCT, 63 female CPPS participants will be recruited and randomized (1:1:1) to high-intensity rTMS, low-intensity rTMS, or sham rTMS. The control group will receive a 10-day course of conventional pelvic floor (PF) rehabilitation (neuromuscular stimulation, magnetic therapy, or light therapy of the PF). On the basis of conventional treatment, participants in the high-intensity rTMS group will receive pulses of 10 Hz with a resting motor threshold (RMT) of 110% for a total of 15,000 pulses. Participants in the low-intensity rTMS group will receive pulses of 10 Hz with an RMT of 80% with 15,000 pulses. The sham rTMS group will be subjected to sham stimulation with the same sound as produced by the real magnetic stimulation coil. The primary outcome will be determined using a visual analog scale, the Genitourinary Pain Index, Zung Self-Rating Anxiety Scale, and Zung Self-Rating Depression Scale. The secondary outcome will be determined by electromyography of the surface of PF muscles at baseline and after treatment completion.

ETHICS AND DISSEMINATION

This study is approved by the Ethics Committee of Bao'an People's Hospital, Shenzhen, Guangdong Province (approval number: BYL20211203). The results will be submitted for publication in peer-reviewed journals and disseminated at scientific conferences (Protocol version 1.0-20220709).

TRIAL REGISTRATION

Chictr.org.cn, ID: ChiCTR2200055615. Registered on 14 January 2022, http://www.chictr.org.cn/showproj.aspx?proj=146720 . Protocol version 1.0-20220709.

Neuromodulation in Chronic Pelvic Pain: A Narrative Review

Chronic primary pelvic pain syndrome (CPPPS) is a heterogeneous disease with unknown pathogenesis and a lack of distinct pathological features, which complicates diagnosis and therapy and has a significant impact on patients' daily life. Because pharmacological management is ineffective and long-term use may result in additional system damage, developing a more effective treatment is critical. Neuromodulation has advanced rapidly over the last few decades, and various types of neuromodulations have demonstrated efficacy in the treatment of CPPPS. In this article we discuss the evolution of neuromodulation technology in the treatment of chronic pelvic pain, its application to various subtypes of chronic pelvic pain, and the comparison of relevant efficacy and parameter differences, as well as assess the relative advantages and disadvantages of sacral neuromodulation, percutaneous tibial nerve stimulation , transcutaneous electrical nerve stimulation, electroacupuncture, and pudendal neuromodulation. Furthermore, it was noted that chronic pelvic pain should be evaluated in terms of pain, associated symptoms, psychological problems, and quality of life. Although neuromodulation approaches have been shown to be effective in treating chronic pelvic pain, more extensive multicenter trials are required to confirm this.

Efficacy of transcutaneous tibial nerve stimulation in the treatment of bladder pain syndrome

Background

This study aimed to demonstrate the effectiveness of transcutaneos tibial nerve stimulation (TTNS) in the treatment of bladder pain syndrome (BPS).

Materials and methods

The data of 16 female patients, diagnosed with BPS in our clinic between 2019 and 2021 and had TTNS twice a week for 12 weeks, were retrospectively analyzed.

Results

The mean age of the patients was 46.00 ± 13.11 years, and the mean body mass index was 26.43 ± 3.07 kg/m². After the treatment, the median day time frequency of the patients decreased from 13.37 (3.69) to 10.25 (4.56) (p < 0.001). Nocturia also decreased after treatment from 4.37 (1.81) to 3.00 (1.94) (p = 0.001). The median voiding volume increased by 26.5 mL (p = 0.001). The median of the patients' visual analog scale scores decreased after treatment (median of visual analog scale score changed from interquartile range 8 [1] to 7 [4]) (p = 0.001). In addition, the median interquartile range interstitial cystitis symptom index scores decreased from 17 (4) to 15 (10) (p = 0.002).

Conclusions

In this study it was demonstrated that TTNS is an alternative method that can be successfully applied before invasive methods in the treatment of BPS.

Effects of neuromodulation on treatment of recurrent anal fissure: A systematic review

BACKGROUND

Anal fissure is a linear tear in the distal anoderm most frequently occurring in the posterior midline. Lateral internal sphincterotomy is considered the gold standard for the treatment of this condition. To this date, several pharmacological and neuromodulatory therapies have been tried out as alternative non-invasive treatments for anal fissures, however, the efficacy of some of these methods remains to be understood.

OBJECTIVE

the primary aim of this study was to review available literature on neuromodulatory treatments for recurrent anal fissure as a potentially effective cure for this condition.

DATA SOURCES

A search was conducted among five main online databases Embase, PubMed, Web of Science, Scopus, and Scholar.

STUDY SELECTION

All published human studies in English literature addressing neuromodulation for the treatment of recurrent anal fissure were selected.

INTERVENTION

neuromodulation for the treatment of anal fissure. We chose to include all articles in which the authors stated that the procedure they performed was via neuromodulation technique, or that the described technique used in their study resembled the technique.

RESULT

Among a total of 3487 evaluated studies, seven represented the effects of neuro modulation on treatment of recurrent anal fissure, among which two were randomized controlled trials and the rest were prospective studies. A total of 186 patient were evaluated in these studies. The mean age of the participants was 46.97 ± 8.2. The average VAS score before intervention was 7.77 ± 2.13, which decreased to 0.31 ± 1.13 after intervention.

LIMITATIONS

limitations of this study include the lack of related articles, and data regarding this subject.

CONCLUSION

Posterior tibial nerve stimulation (PTNS) provides rapid pain relief and fissure healing especially in short-to mid-terms with little to no complications, however, using this treatment, symptoms of anal fissure do not improve as well as LIS, especially in the long-term.

Parametric Assessment of Spinal Cord Stimulation on Bladder Pain-Like Responses in Rats

OBJECTIVES

Spinal cord stimulation (SCS) for the treatment of pelvic visceral pains has been understudied and underused. The goal of the current study was to examine multiple stimulation parameters of SCS to determine optimal settings for the inhibition of responses to urinary bladder distension (UBD) in animal models of bladder pain as a guide for human studies.

MATERIALS AND METHODS

Adult, female isoflurane/urethane-anesthetized rats underwent a T13/L1 mini-laminectomy sufficient to implant an SCS paddle lead for neuromodulation. Silver wire electrodes were inserted into the external oblique musculature. A 22-gauge angiocatheter was placed transurethrally into the bladder and used to deliver phasic, air UBDs at pressures of 10 to 60 mm Hg and visceromotor (abdominal contractile) electromyographic responses to UBD measured in the presence and absence of SCS. Electromyographic activity was quantified using standard differential amplification and rectification. Parameter settings for SCS included both conventional (10, 50, 100 Hz) and high frequency (1,000, 5,000, and 10,000 Hz) biphasic square wave pulses with 50 to 200 μs durations. To create states of hypersensitivity, pretreatment of adult rats included an intravesical zymosan infusion 24 hours before testing with and without a preceding episode of neonatal bladder inflammation.

RESULTS

Low frequency (10, 50, and 100 Hz) 200 μs biphasic pulses at submotor thresholds demonstrated inhibition of visceromotor responses (VMRs) to UBD in rats made hypersensitive to UBD by a protocol that included neonatal cystitis. Onset of inhibitory effects occurred within 20 minutes of beginning SCS. Otherwise, SCS at all other parameters studied and in other tested rat models produced either no significant effect or augmentation of VMRs.

CONCLUSIONS

Demonstration of inhibitory effects of SCS in a clinically relevant model of bladder pain suggests the potential utility of this therapy in patients with painful bladder disorders.

Spinal cord stimulation in the approach to chronic pelvic pain: A case report and literature review

RATIONALE

Chronic pelvic pain (CPP) is a pain related to pelvic structures that arise from posttraumatic pain, postsurgical pain, or somatic or visceral pain syndromes. Despite the available treatment options, CPP remains mostly untreated, due to difficulties in covering such a large area.

PATIENT CONCERNS

A 46-year-old woman presented chronic low back pain and CPP for more than 1 year and 6 months respectively after multiple pelvic fractures.

DIAGNOSIS

Pelvic fractures and a severe lumbar facet arthrosis were revealed through computed tomography and lumbosacral nuclear magnetic resonance imaging. Evidence of a reduced amplitude in the left femoral nerve and a demyelinating neuropathy in the left pudendal nerve were also detected.

INTERVENTION

A pharmacologic treatment was prescribed, consisting of celecoxib, fluoxetine, gabapentin, and morphine. Since no pain relief was achieved, spinal cord stimulation was performed using spectra WaveWriter system, placing 2 octopolar linear leads over the bilateral T8 and T9 vertebras with the help of a 3-dimensional neural targeting program.

OUTCOMES

Two weeks after the intervention a reduction of 80% of the pain was achieved, which led to the removal of the pharmacologic treatment. Additionally, both EuroQOL-5D and visual analogue scale scores improved after the intervention.

LESSON

Through the combination of spinal cord stimulation Spectra Wavewriter and 3D programming technology, both lumbar and leg pain and CPP were successfully relieved, along with an improvement in the quality of life of the patient.

Peripheral Nerve Stimulation for Chronic Pain: A Systematic Review of Effectiveness and Safety

Peripheral nerve stimulation (PNS) was the first application of neuromodulation. Widespread application of PNS was limited by technical concerns. Recent advances now allow the percutaneous placement of leads with ultrasound or fluoroscopic guidance, while the transcutaneous powering of these leads removes the need for leads to cross major joints. This systematic review was written to assess the current status of high-quality evidence supporting the use of PNS for pain conditions treated by interventional pain physicians. The available literature on PNS, limited to conditions treated by interventional pain physicians, was reviewed and the quality assessed. Literature from 1966 to June 2021 was reviewed. The outcome measures were pain relief and functional improvement. One hundred and two studies were identified. Five randomized controlled trials (RCT) and four observational studies, all case series, met the inclusion criteria. One RCT was of high quality and four were of moderate quality; all four case series were of moderate quality. Three of the RCTs and all four case series evaluated peripheral nerve neuropathic pain. Based upon these studies, there is level II evidence supporting the use of PNS to treat refractory peripheral nerve injury. One moderate-quality RCT evaluated tibial nerve stimulation for pelvic pain, providing level III evidence for this indication. One moderate-quality RCT evaluated surgically placed cylindrical leads for cluster headaches, providing level III evidence for this indication. The evidence suggests that approximately two-thirds of patients with peripheral neuropathic pain will have at least 50% sustained pain relief. Adverse events from PNS are generally minor. A major advantage of PNS over spinal cord stimulation is the absence of any risk of central cord injury. The study was limited by the paucity of literature for some indications. No studies dealt with joint-related osteoarthritic pain.

Does TENS Reduce the Intensity of Acute and Chronic Pain? A Comprehensive Appraisal of the Characteristics and Outcomes of 169 Reviews and 49 Meta-Analyses

Background and Objectives: Uncertainty about the clinical efficacy of transcutaneous electric nerve stimulation (TENS) to alleviate pain spans half a century. There has been no attempt to synthesise the entire body of systematic review evidence. The aim of this comprehensive review was to critically appraise the characteristics and outcomes of systematic reviews evaluating the clinical efficacy of TENS for any type of acute and chronic pain in adults. Materials and Methods: We searched electronic databases for full reports of systematic reviews of studies, overviews of systematic reviews, and hybrid reviews that evaluated the efficacy of TENS for any type of clinical pain in adults. We screened reports against eligibility criteria and extracted data related to the characteristics and outcomes of the review, including effect size estimates. We conducted a descriptive analysis of extracted data. Results: We included 169 reviews consisting of eight overviews, seven hybrid reviews and 154 systematic reviews with 49 meta-analyses. A tally of authors' conclusions found a tendency toward benefits from TENS in 69/169 reviews, no benefits in 13/169 reviews, and inconclusive evidence in 87/169 reviews. Only three meta-analyses pooled sufficient data to have confidence in the effect size estimate (i.e., pooled analysis of >500 events). Lower pain intensity was found during TENS compared with control for chronic musculoskeletal pain and labour pain, and lower analgesic consumption was found post-surgery during TENS. The appraisal revealed repeated shortcomings in RCTs that have hindered confident judgements about efficacy, resulting in stagnation of evidence. Conclusions: Our appraisal reveals examples of meta-analyses with 'sufficient data' demonstrating benefit. There were no examples of meta-analyses with 'sufficient data' demonstrating no benefit. Therefore, we recommend that TENS should be considered as a treatment option. The considerable quantity of reviews with 'insufficient data' and meaningless findings have clouded the issue of efficacy. We offer solutions to these issues going forward.

Interventional treatment options for women with pelvic pain

Purpose of review

I.To provide an overview of current interventional treatment options for women with chronic pelvic pain (CPP).

Recent findings

II.Accessibility of CT imaging, ultrasound, and fluoroscopy have assisted the development of novel interventional techniques. Similarly, neuromodulation techniques have improved with the development of novel stimulation patterns and device implants.

Summary

III.Numerous small-scale studies report high success rates with injection intervention therapies in CPP but there are limited well designed large-scale studies that demonstrate superiority of treatment. Female pelvic pain is difficult to diagnose due to the multifactorial etiology and the variable presentation causing delay in accurate diagnosis and lack of response to conventional medical and initial interventional therapies. Despite the shortfalls of current studies, collectively our understanding of chronic pain conditions and helpful injection interventions are improving. Undoubtedly the breadth of current research will provide a rich foundation for future large-scale well-designed studies involving multiple disciplines with more uniform methods and criteria to produce reliable and reproducible results.