Biofeedback combined with percutaneous electrical pudendal nerve stimulation for the treatment of low anterior rectal resection syndrome: a study protocol for a randomized controlled trial.

BACKGROUND: Low anterior resection syndrome (LARS) is a distressing condition that affects approximately 25-80% of patients following surgery for rectal cancer. LARS is characterized by debilitating bowel dysfunction symptoms, including fecal incontinence, urgent bowel movements, and increased frequency of bowel movements. Although biofeedback therapy has demonstrated effectiveness in improving postoperative rectal control, the research results have not fulfilled expectations. Recent research has highlighted that stimulating the pudendal perineal nerves has a superior impact on enhancing pelvic floor muscle function than biofeedback alone. Hence, this study aims to evaluate the efficacy of a combined approach integrating biofeedback with percutaneous electrical pudendal nerve stimulation (B-PEPNS) in patients with LARS through a randomized controlled trial (RCT). METHODS AND ANALYSIS: In this two-armed multicenter RCT, 242 participants with LARS after rectal surgery will be randomly assigned to undergo B-PEPNS (intervention group) or biofeedback (control group). Over 4 weeks, each participant will undergo 20 treatment sessions. The primary outcome will be the LARS score. The secondary outcomes will be anorectal manometry and pelvic floor muscle electromyography findings and the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-Colorectal 29 (EORTC QLQ-CR29) scores. Data will be collected at baseline, post-intervention (1 month), and follow-up (6 months). DISCUSSION: We anticipate that this study will contribute further evidence regarding the efficacy of B-PEPNS in alleviating LARS symptoms and enhancing the quality of life for patients following rectal cancer surgery. TRIAL REGISTRATION: Chinese Clincal Trials Register ChiCTR2300078101. Registered 28 November 2023.

Endovascular stimulation of the pudendal nerve using a stent-mounted electrode array.

Objective. Previous preclinical and clinical studies have demonstrated that pudendal nerve is a promising target for restoring bladder control. The spatial proximity between the pudendal nerve and its accompanying blood vessels in the pudendal canal provides an opportunity for endovascular neurostimulation, which is a less invasive approach compared to conventional chronically implanted electrodes. In this study, we investigated the feasibility of excitatory stimulation and kilohertz-frequency block of the compound pudendal nerve in sheep using a stent-mounted electrode array.Approach. In a set of acute animal experiments, a commercially available hexapolar electrode catheter was introduced in the unilateral internal pudendal artery to deliver bipolar electrical stimulation of the adjacent compound pudendal nerve. The catheter electrode was replaced with a custom-made stent-mounted electrode array and the stimulation sessions were repeated. Global electromyogram activity of the pelvic floor and related sphincter muscles was recorded with a monopolar electrode placed within the urethra concurrently.Main results. We demonstrated the feasibility of endovascular stimulation of the pudendal nerve with both electrode types. The threshold current of endovascular stimulation was influenced by electrode-nerve distance and electrode orientation. Increasing the axial inter-electrode distance significantly decreased threshold current. Endovascular kilohertz-frequency nerve block was possible with the electrode catheter.Significance. The present study demonstrated that endovascular stimulation of the pudendal nerve with the stent-mounted electrode array may be a promising less invasive alternative to conventional implantable electrodes, which has important clinical implications in the treatment of urinary incontinence. Endovascular blocking of pudendal nerve may provide an alternative solution to the bladder-sphincter dyssynergia problem in bladder management for people with spinal cord injury.

Adrenergic relaxations in an in situ urinary bladder model evoked by stimulation of sensory pelvic and pudendal nerves in the rat.

Urinary bladder dysfunction might be related to disturbances at different levels of the micturition reflex arc. The current study aimed to further develop and evaluate a split bladder model for detecting and analysing relaxatory signalling in the rat urinary bladder. The model allows for discrimination between effects at the efferent and the afferent side of the innervation. In in vivo experiments, the stimulation at a low frequency (1 Hz) of the ipsilateral pelvic nerve tended to evoke relaxation of the split bladder half (contralateral side; -1.0 ± 0.4 mN; n = 5), in contrast to high frequency-evoked contractions. In preparations in which the contralateral pelvic nerve was cut the relaxation occurred at a wider range of frequencies (0.5-2 Hz). In separate experiments, responses to 1 and 2 Hz were studied before and after intravenous injections of propranolol (1 mg/kg IV). The presence of propranolol significantly shifted the relaxations into contractions. Also, electrical stimulation of the ipsilateral pudendal nerve evoked relaxations of similar magnitude as for the pelvic stimulations, which were also affected by propranolol. In control in vitro experiments, substances with ß-adrenoceptor agonism, in contrast to a selective α-agonist, evoked relaxations. The current study shows that the split bladder model can be used for in vivo studies of relaxations. In the model, reflex-evoked sympathetic responses caused relaxations at low intensity stimulation. The involvement of ß-adrenoceptors is supported by the sensitivity to propranolol and by the in vitro observations.

Surgical approaches for pudendal nerve entrapment: insights from a systematic review and meta-analysis.

BACKGROUND: Pudendal nerve entrapment (PNE) is an underdiagnosed condition affecting a spectrum of pelvic functions, primarily pain, as outlined by Nantes diagnostic criteria. Although numerous surgical decompression techniques are available for its management, consensus on efficacy and safety is lacking. This study conducts a systematic review and meta-analysis to assess the efficacy and complication rates of the main surgical decompression techniques. METHODS: A comprehensive literature search was conducted in PubMed®, Embase®, Web of Science®, and ClinicalTrails.gov® on 19th of April 2023. Initial screening involved title and abstract evaluation, with subsequent retrieval and assessment of abstracts and full-text articles. Studies assessing pain outcomes before and after surgical release of the pudendal nerve were included. Studies without full-text, focusing on diagnostic methods or with outcomes relating solely to LUTS, digestive symptoms, or sexual dysfunction, were excluded. Risk of bias assessement was conducted using the National Institute of Health (NIH) Study Quality Assessment tool. Studies were categorized based on three surgical techniques: perineal, transgluteal, and laparoscopic transperitoneal. Random-effects meta-analysis with subgroup analysis were used. Meta-regression analyses were conducted to investigate the influence of covariates on the observed outcomes. RESULTS: Nineteen studies, comprising 810 patients, were included. The overall significant pain relief rate across all techniques was estimated at 0.67 (95% CI 0.54 to 0.78) with considerable heterogeneity (I2 = 80.4%). Subgroup analysis revealed success rate for different techniques: laparoscopic (0.91, 95% CI 0.64 to 0.98), perineal (0.69, 95% CI 0.52 to 0.82), and transgluteal (0.50, 95% CI 0.37 to 0.63). The laparoscopic technique exhibited a complication rate of 16.0%. Meta-regression indicated that patient age and median follow-up significantly influenced outcomes. CONCLUSION: While comparing surgical techniques is challenging, this meta-analysis highlights important outcome differences. The laparoscopic technique appears most promising for pain improvement. However, the study also emphasizes the need for further robust, long-term research due to significant heterogeneity across studies and prevelent risk of bias. PROSPERO database: CRD42023496564.

Efficacy of ganglion impar block combined with pudendal nerve pulsed radiofrequency for pudendal neuralgia management-a randomized clinical trial.

BACKGROUND: Pudendal neuralgia is a chronic and debilitating condition. Its prevalence ranges from 5 to 26%. Currently, therapeutic approaches to treat pudendal neuralgia include patient education, medication management, psychological and physical therapy, and procedural interventions, such as nerve block, trigger point injections, and surgery. Drug therapy has a limited effect on pain relief. A pudendal nerve block may cause a significant decrease in pain scores for a short time; however, its efficacy significantly decreases over time. In contrast, pudendal nerve pulsed radiofrequency can provide pain relief for 3 months, and ganglion impar block has been widely used for treating chronic perineal pain and chronic coccygodynia. This study aimed to determine the efficacy and safety of monotherapy (pudendal nerve pulsed radiofrequency) and combination therapy (pudendal nerve pulsed radiofrequency plus ganglion impar block) in patients with pudendal neuralgia. METHODS: This randomized, controlled clinical trial will include 84 patients with pudendal neuralgia who failed to respond to drug or physical therapy. Patients will be randomly assigned into one of the two groups: mono or combined treatment groups. The primary outcome will be a change in pain intensity measured using the visual analog scale. The secondary outcomes will include a Self-Rating Anxiety Scale score, Self-Rating Depression Scale score, the use of oral analgesics, the Medical Outcomes Study Health Survey Short Form-36 Item score, and the occurrence of adverse effects. The study results will be analyzed using intention-to-treat and per-protocol analyses. Primary and secondary outcomes will be evaluated between the mono and combined treatment groups. Subgroup analyses will be conducted based on the initial ailment, age, and baseline pain intensity. The safety of the treatment will be assessed by monitoring adverse events, which will be compared between the two groups. DISCUSSION: This study protocol describes a randomized, controlled clinical trial to determine the efficacy and safety of mono and combination therapies in patients with pudendal neuralgia. The study results will provide valuable information on the potential benefits of this combination therapy and contribute to the development of more effective and safer treatments for patients with pudendal neuralgia. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2200061800).

Pudendal nerve neurolysis outcomes for urogenital and rectal disorders in patients suffering from pudendal nerve entrapment: A systematic review.

PURPOSE: Pudendal neuropathy is an uncommon condition that exhibits several symptoms depending on the site of nerve entrapment. This study aims to evaluate the efficacy of pudendal nerve neurolysis (PNN) in improving lower urinary tract symptoms, anal and/or urinary incontinence, and sexual dysfunctions. MATERIALS AND METHODS: A systematic literature search was performed on 20 May 2023 using Scopus, PubMed, and Embase. Only English and adult papers were included. Meeting abstracts and preclinical studies were excluded. RESULTS: Twenty-one papers were accepted, revealing significant findings in the field. The study identified four primary sites of pudendal nerve entrapment (PNE), with the most prevalent location likely being at the level of the Alcock canal. Voiding symptoms are commonly exhibited in patients with PNE. PNN improved both urgency and voiding symptoms, and urinary and anal incontinence but is less effective in cases of long-standing entrapment. Regarding sexual function, the recovery of the somatic afferent pathway results in an improvement in erectile function early after neurolysis. Complete relief of persistent genital arousal disorder occurs in women, although bilateral PNN is necessary to achieve the efficacy. PNN is associated with low-grade complications. CONCLUSIONS: PNN emerges as a viable option for addressing urinary symptoms, fecal incontinence, erectile dysfunction, and female sexual arousal in patients suffering from PNE with minimal postoperative morbidity.

Lumbosacral plexus and pudendal nerve magnetic resonance tractography: A systematic review of the clinical applications for pudendal neuralgia.

Diffusion tensor imaging (DTI) is commonly used to establish three-dimensional mapping of white-matter bundles in the supraspinal central nervous system. DTI has also been the subject of many studies on cranial and peripheral nerves. This non-invasive imaging technique enables virtual dissection of nerves in vivo and provides specific measurements of microstructural integrity. Adverse effects on the lumbosacral plexus may be traumatic, compressive, tumoral, or malformative and thus require dedicated treatment. DTI could lead to new perspectives in pudendal neuralgia diagnosis and management. We performed a systematic review of all articles or posters reporting results and protocols for lumbosacral plexus mapping using the DTI technique between January 2011 and December 2023. Twenty-nine articles published were included. Ten studies with a total of 351 participants were able to track the lumbosacral plexus in a physiological context and 19 studies with a total of 402 subjects tracked lumbosacral plexus in a pathological context. Tractography was performed on a 1.5T or 3T MRI system. DTI applied to the lumbosacral plexus and pudendal nerve is feasible but no microstructural normative value has been proposed for the pudendal nerve. The most frequently tracking parameters used in our review are: 3T MRI, b-value of 800 s/mm2, 33 directions, 3 × 3 × 3 mm3, AF threshold of 0.1, minimum fiber length of 10 mm, bending angle of 30°, and 3DT2 TSE anatomical resolution. Increased use of DTI could lead to new perspectives in the management of pudendal neuralgia due to entrapment syndrome, whether at the diagnostic, prognostic, or preoperative planning level. Prospective studies of healthy subjects and patients with the optimal acquisition parameters described above are needed to establish the accuracy of MR tractography for diagnosing pudendal neuralgia and other intrapelvic nerve entrapments.

Accuracy of augmented reality-guided needle placement for pulsed radiofrequency treatment of pudendal neuralgia: a pilot study on a phantom model.

Background: Pudendal neuralgia (PN) is a chronic neuropathy that causes pain, numbness, and dysfunction in the pelvic region. The current state-of-the-art treatment is pulsed radiofrequency (PRF) in which a needle is supposed to be placed close to the pudendal nerve for neuromodulation. Given the effective range of PRF of 5 mm, the accuracy of needle placement is important. This study aimed to investigate the potential of augmented reality guidance for improving the accuracy of needle placement in pulsed radiofrequency treatment for pudendal neuralgia. Methods: In this pilot study, eight subjects performed needle placements onto an in-house developed phantom model of the pelvis using AR guidance. AR guidance is provided using an in-house developed application on the HoloLens 2. The accuracy of needle placement was calculated based on the virtual 3D models of the needle and targeted phantom nerve, derived from CBCT scans. Results: The median Euclidean distance between the tip of the needle and the target is found to be 4.37 (IQR 5.16) mm, the median lateral distance is 3.25 (IQR 4.62) mm and the median depth distance is 1.94 (IQR 7.07) mm. Conclusion: In this study, the first method is described in which the accuracy of patient-specific needle placement using AR guidance is determined. This method could potentially improve the accuracy of PRF needle placement for pudendal neuralgia, resulting in improved treatment outcomes.

Comparison of the effects of ring block and dorsal penile nerve block on parental satisfaction for circumcision operation in children: randomized controlled trial.

PURPOSE: In children, circumcision is a procedure associated with perioperative pain and parental satisfaction is an important parameter in the evaluation of anesthesia procedures. Inadequate dorsal penile nerve block (DPNB) for the ventral shaft of the penis might impact parental satisfaction negatively. To evaluate this hypothesis, we compared the effects of penile ring block (RB) and dorsal penile nerve block (DPNB) on parental satisfaction. Postoperative pain, need for additional analgesia, intraoperative hemodynamic data, recovery status, side effects, and postoperative complications were evaluated as secondary outcomes between the blocks. METHODS: Parental satisfaction and anesthetic effectiveness of RB and DPNB for circumcision in children were compared. 86 patients were randomized 1:1 to Group RB and Group DPNB, which were administered the same dose of anesthesia. Parental satisfaction was evaluated with the Pediatric Anesthesia Parental Satisfaction Questionnaire (PAPS). Postoperative pain evaluations were made with the Face, Legs, Activity, Crying, Consolability Pain Scale (FLACC). RESULTS: In terms of parent satisfaction, no differences were detected between the groups in the pre-anesthesia, pre-anesthesia and post-anesthesia, post-anesthesia, hospital team, and anesthesia team parameters (p > 0.05). The scores of Group DPNB patients were higher only in the "Q11" subparameter in the "anesthesia team" parameter, and this difference was significant (0.024). CONCLUSION: RB and DPNB were compared in circumcision, which is the most common surgical procedure for children. Parental satisfaction, anesthesia, and analgesic effects of both blocks were found to be similar. CLINICAL TRIALS: ACTRN12622001211752.

Short-Term Dorsal Genital Nerve Stimulation Increases Subjective Arousal in Women With and Without Spinal Cord Injury: A Preliminary Investigation.

OBJECTIVES: Female sexual dysfunction (FSD) affects an estimated 40% of women. Unfortunately, FSD is understudied, leading to limited treatment options for FSD. Neuromodulation has shown some success in alleviating FSD symptoms. We developed a pilot study to investigate the short-term effect of electrical stimulation of the dorsal genital nerve and tibial nerve on sexual arousal in healthy women, women with FSD, and women with spinal cord injury (SCI) and FSD. MATERIALS AND METHODS: This study comprises a randomized crossover design in three groups: women with SCI, women with non-neurogenic FSD, and women without FSD or SCI. The primary outcome measure was change in vaginal pulse amplitude (VPA) from baseline. Secondary outcome measures were changes in subjective arousal, heart rate, and mean arterial pressure from baseline. Participants attended one or two study sessions where they received either transcutaneous dorsal genital nerve stimulation (DGNS) or tibial nerve stimulation (TNS). At each session, a vaginal photoplethysmography sensor was used to measure VPA. Participants also rated their level of subjective arousal and were asked to report any pelvic sensations. RESULTS: We found that subjective arousal increased significantly from before to after stimulation in DGNS study sessions across all women. TNS had no effect on subjective arousal. There were significant differences in VPA between baseline and stimulation, baseline and recovery, and stimulation and recovery periods among participants, but there were no trends across groups or stimulation type. Two participants with complete SCIs experienced genital sensations. CONCLUSIONS: To our knowledge, this is the first study to measure sexual arousal in response to short-term neuromodulation in women. This study indicates that short-term DGNS but not TNS can increase subjective arousal, but the effect of stimulation on genital arousal is inconclusive. This study provides further support for DGNS as a treatment for FSD.

Pudendal Block at the Time of Transvaginal Prolapse Repair: A Randomized Controlled Trial.

IMPORTANCE: The utility of pudendal nerve blocks (PNBs) at the time of transvaginal surgery is mixed in the literature. No published study has evaluated the efficacy of PNB since the widespread adoption of Enhanced Recovery After Surgery (ERAS) pathways. OBJECTIVE: This study aimed to determine if PNB, in addition to ERAS measures, at the time of vaginal reconstructive surgery reduces opioid use in the immediate postoperative period. STUDY DESIGN: In this randomized, blinded, controlled trial, women scheduled for transvaginal multicompartment prolapse repair were randomized to bilateral PNB before incision with 20 mL of 0.5% bupivacaine versus usual care. Primary outcome was opioid use in morphine milligram equivalents (MME) for the first 24 hours. The study was powered to detect a 5.57-MME difference in opioid use in the first 24 hours between groups. RESULTS: Forty-four patients were randomized from January 2020 to April 2022. The PNB and control groups were well matched in demographic and surgical data. There was no difference in opioid use in first 24 hours between the control and PNB groups (8 [0-20] vs 6.7 [0-15]; P = 0.8). Median pain scores at 24 and 48 hours did not differ between groups (4 ± 2 vs 3 ± 3; P = 0.44) and 90% of participants were satisfied with pain control across both groups. Time to return to normal activities (median, 10 days) was also not different between the groups. CONCLUSIONS: Because pain satisfaction after transvaginal surgery in the era of ERAS is high, with overall low opioid requirements, PNB provides no additional benefit.

Nerve transfer for restoration of lower motor neuron-lesioned bladder, urethral and anal sphincter function. Part 4: Effectiveness of the motor reinnervation.

In pilot work, we showed that somatic nerve transfers can restore motor function in long-term decentralized dogs. We continue to explore the effectiveness of motor reinnervation in 30 female dogs. After anesthesia, 12 underwent bilateral transection of coccygeal and sacral (S) spinal roots, dorsal roots of lumbar (L)7, and hypogastric nerves. Twelve months postdecentralization, eight underwent transfer of obturator nerve branches to pelvic nerve vesical branches, and sciatic nerve branches to pudendal nerves, followed by 10 mo recovery (ObNT-ScNT Reinn). The remaining four were euthanized 18 mo postdecentralization (Decentralized). Results were compared with 18 Controls. Squat-and-void postures were tracked during awake cystometry. None showed squat-and-void postures during the decentralization phase. Seven of eight ObNT-ScNT Reinn began showing such postures by 6 mo postreinnervation; one showed a return of defecation postures. Retrograde dyes were injected into the bladder and urethra 3 wk before euthanasia, at which point, roots and transferred nerves were electrically stimulated to evaluate motor function. Upon L2-L6 root stimulation, five of eight ObNT-ScNT Reinn showed elevated detrusor pressure and four showed elevated urethral pressure, compared with L7-S3 root stimulation. After stimulation of sciatic-to-pudendal transferred nerves, three of eight ObNT-ScNT Reinn showed elevated urethral pressure; all showed elevated anal sphincter pressure. Retrogradely labeled neurons were observed in L2-L6 ventral horns (in laminae VI, VIII, and IX) of ObNT-ScNT Reinn versus Controls in which labeled neurons were observed in L7-S3 ventral horns (in lamina VII). This data supports the use of nerve transfer techniques for the restoration of bladder function.NEW & NOTEWORTHY This data supports the use of nerve transfer techniques for the restoration of bladder function.

Contribution of pudendal nerve injury to stress urinary incontinence in a male rat model.

Urinary incontinence is a common complication following radical prostatectomy, as the surgery disturbs critical anatomical structures. This study explored how pudendal nerve (PN) injury affects urinary continence in male rats. In an acute study, leak point pressure (LPP) and external urethral sphincter electromyography (EMG) were performed on six male rats with an intact urethra, the urethra exposed (UE), the PN exposed (NE), and after PN transection (PNT). In a chronic study, LPP and EMG were tested in 67 rats 4 days, 3 weeks, or 6 weeks after sham PN injury, PN crush (PNC), or PNT. Urethras were assessed histologically. Acute PNT caused a significant decrease in LPP and EMG amplitude and firing rate compared to other groups. PNC resulted in a significant reduction in LPP and EMG firing rate 4 days, 3 weeks, and 6 weeks later. EMG amplitude was also significantly reduced 4 days and 6 weeks after PNC. Neuromuscular junctions were less organized and less innervated after PNC or PNT at all timepoints compared to sham injured animals. Collagen infiltration was significantly increased after PNC and PNT compared to sham at all timepoints. This rat model could facilitate preclinical testing of neuroregenerative therapies for post-prostatectomy incontinence.

Combined Decompression of Pudendal and Inferior Cluneal Nerves for Entrapment Neuralgias Using Transperitoneal Robotic Laparoscopy: Feasibility and Our Four-Step Technique.

OBJECTIVE: To demonstrate the feasibility of a combined decompression of pudendal and inferior cluneal nerves for entrapment syndrome using a transperitoneal robotic laparoscopy. DESIGN: Demonstration of our 4-step technique with narrated video footage. SETTING: Pudendal and inferior cluneal neuralgias caused by an entrapment syndrome are both responsible for perineal pain [1]. Although more precise data are lacking, these 2 neuralgias are frequently associated. Failure of surgical pudendal nerve decompression in the early 2000 has driven to discover the entity of a potential entrapment syndrome of the posterior cutaneous nerve of the tight and its inferior cluneal branches between the ischium bone and the sacrotuberous ligament [2]. The corresponding neuralgia is responsible for a neuropathic pain to a more posterior part of the perineum and the thigh, without any neurovegetative symptom. In case of failure of medical treatment, surgery can be proposed using an invasive open transgluteal approach as a standard treatment [3-5]. INTERVENTIONS: Transperitoneal robotic laparoscopy for a mini-invasive releasing of both pudendal and inferior cluneal nerves, following a 4-step technique: 1. Opening of the peritoneum between the external iliac vessels and the umbilical ligament 2. Dissection of the internal iliac and pudendal arteries up to the pudendal nerve 3. Section of the sacrospinous ligament and release of the pudendal nerve 4. Section of the sacrotuberous ligament and release of the inferior cluneal nerve CONCLUSION: Previously, pudendal and inferior cluneal neuralgias have been managed with an invasive open transgluteal surgery. Here, we demonstrate the feasibility of a mini-invasive transperitoneal robotic laparoscopy, with a standardized 4-step surgical technique. VIDEO ABSTRACT.

Pudendal nerve blockade for persistent genital arousal disorder (PGAD): A clinical review and case report.

BACKGROUND: Persistent genital arousal disorder (PGAD) is a condition characterized by unwanted and potentially painful genital sensations or spontaneous orgasms without stimulation. We present a case of a 55-year-old woman with refractory genital arousal disorder that was treated with serial pudendal nerve blocks. CASE: RW is a 55-year-old woman with chronic pelvic pain, pudendal neuralgia, MDD, SI, GAD, CRPS, and persistent genital arousal disorder for 11 years. Her PGAD was refractory to conservative management, physical therapy, and bilateral clitoral artery embolization. We performed bilateral pudendal nerve blocks with Kenalog and Bupivacaine, which provided almost complete relief for 2-3 months. We performed a bilateral pudendal nerve radiofrequency ablation; however, there was minimal benefit. RW continues to have significant relief with serial pudendal nerve blocks. SUMMARY AND CONCLUSION: Persistent genital arousal disorder is often refractory to medication and physical therapy requiring significant intervention such as entrapment surgery or artery embolization. Our case demonstrates pudendal nerve blocks as a potential treatment modality with minimal side effects.

Can nerve monitoring during radical prostatectomy improve functional outcomes? A randomised trial.

OBJECTIVE: To explore how the use of the ProPep® Nerve Monitoring System (ProPep Surgical, Austin, TX, USA) for intraoperative specific sparing of the pudendal nerve fibres influences postoperative functional outcomes after unilateral nerve-sparing (UNS) or non-nerve-sparing (NNS) robot-assisted radical prostatectomy (RARP). PATIENTS AND METHODS: We randomised 100 men undergoing UNS or NNS RARP to ProPep nerve monitoring during RARP (intervention) or standard of care RARP (control). Functional outcomes were assessed at 3, 6, and 12 months using the International Consultation on Incontinence Questionnaire Short Form (ICIQ-SF), the International Prostate Symptom Score, the Danish Prostate Symptom Score, the International Index of Erectile Function, the Erection Hardness Scale, and 24-h pad tests. The primary outcome was the difference in ICIQ-SF score between the groups at 12 months. Secondary outcomes included differences in the remaining outcome measures and continence rates at all time points. Continence was defined as the use of no pads and the answer 'Never' to the question: 'How often do you experience urinary incontinence?' or a urine loss of <8 g on the 24-h pad test. RESULTS: A total of 82 patients were included in the per-protocol analysis at 12 months with 41 in each group. At 12 months the mean ICIQ-SF scores were 5.37 (95% confidence interval [CI] 3.71-7.03) and 5.66 (95% CI 4.05-7.27) for the intervention and control groups, respectively (P = 0.8). There were no statistically significant differences in any of the remaining outcomes. However, the continence rate was higher in the intervention group at 6 months (63% vs 44%, P = 0.09). CONCLUSIONS: Intraoperative nerve monitoring did not result in better functional outcomes following UNS or NNS RARP. Larger studies are needed to explore if ProPep can reduce the time to continence after RARP.

Use of pudendal nerve blocks in rubber band ligation of haemorrhoids: an Australia-wide cross-sectional analysis.

BACKGROUND: Surgeons vary in their approach to preventing pain post rubber band ligation (RBL) of haemorrhoids, with pudendal nerve blocks (PNB) being one analgesic strategy. No data exists on how commonly PNBs are used in RBL in Australia, and whether use varies by year and patient and hospital characteristics. METHODS: Aggregate data from the National Hospital Morbidity Database was obtained for all admissions for RBL in Australia from 2012 to 2021, with and without a PNB, overall and in relation to sex, age group, hospital remoteness, hospital sector, and year of procedure. Adjusted relative risks (adj. RR) of PNB were estimated using Poisson regression, mutually adjusting for all variables. RESULTS: Of the 346 542 admissions for RBL, 14013 (4.04%) involved a PNB. The proportion of patients receiving a PNB increased between 2012-2013 and 2020-2021, from 1.62% to 6.63% (adj. RR 3.99, CI 3.64-4.36). Patients most likely to receive a PNB were female (adj. RR 1.10; CI 1.07-1.14) aged 25-34 years (adj. RR 1.13; CI 1.01-1.26); in major-city (adj. RR 1.25 CI 1.20-1.30) and private hospitals (adj. RR 3.28 CI 3.13-3.45). CONCLUSION: This is the first published analysis of the use of PNB in RBL. Pudendal nerve block use has increased over time, with substantial variation in practice. Blocks were more than three times as likely to be used in private compared to public hospitals. If evidence supporting PNB use is established, equitable access to the procedure should be pursued.

Anatomical Relationships of the Sciatic Nerve and Pudendal Nerve to the Ischial Spine as They Exit the Greater Sciatic Foramen.

OBJECTIVE: Deep gluteal syndrome is a clinical condition in which discomfort may arise due to the pathoanatomy of the subgluteal space. We conducted an anatomical exploration to categorize the relationship of the piriformis muscle, sciatic nerve (SN), and pudendal nerve (PN) to the ischial spine (IS) and sacrospinous ligament. METHODS: We analyzed 22 cadavers. The piriformis muscle, SN, and PN were exposed through either a transgluteal approach or a gluteal flap. The relationship of the neural structures to the IS, sacrospinous ligament, and ischial bone as they exit the greater sciatic foramen was observed, and the exit zones were classified as zone A, medial to the IS (entirely on sacrospinous ligament); zone B, on the IS; and zone C, lateral to the IS (entirely on ischial bone). RESULTS: The SN was observed either in zone B or zone C in all specimens. The PN was found to be in either zone A or zone B in 97.6% of specimens. The most common combinations were SN in zone B and PN in zone A (type I), and SN in zone C and PN in zone B (type II). CONCLUSIONS: The results from this study show clear anatomical differences in the SN-PN relationship, which may play a role in pain seen in deep gluteal syndrome. Moreover, classification of the SN-IS and PN-IS relationships described in this article will help describe different pathologies affecting the deep gluteal area.