Anatomy of the pudendal nerve in clinically important areas: a pictorial essay and narrative review.

PURPOSE: The pudendal nerve is an anatomical structure arising from the ventral branches of the spinal roots S2-S4. Its complex course may be affected by surrounding structures. This may result in irritation or entrapment of the nerve with subsequent clinical symptoms. Aim of this study is to review the anatomy of the pudendal nerve and to provide detailed photographic documentation of the areas with most frequent clinical impact which are essential for surgical approach. METHODS: Major medical databases were searched to identify all anatomical studies investigating pudendal nerve and its variability, and possible clinical outcome of these variants. Extracted data consisted of morphometric parameters, arrangement of the pudendal nerve at the level of roots, formation of pudendal nerve, position according to sacrospinal and sacrotuberal ligaments and its terminal branches. One female cadaver hemipelvis was dissected with common variability of separate course of inferior rectal nerve. During dissection photodocumentation was made to record course of pudendal nerve with focus on areas with recorded pathologies and areas exposed to iatrogenic damage during surgical procedures. RESULTS: Narrative review was done to provide background for photodocumentation. Unique photos of course of the pudendal nerve was made in areas with great clinical significance. CONCLUSION: Knowledge of anatomical variations and course of the pudendal nerve is important for examinations and surgical interventions. Surgically exposed areas may become a site for iatrogenic damage of pudendal nerve; therefore, unique picture was made to clarify topographic relations.

First case-series of robot-assisted pudendal nerve release: technique and outcomes.

OBJECTIVE: Pudendal Nerve Entrapment (PNE) may determine chronic pelvic pain associated with symptoms related to its innervation area. This study aimed to present the technique and report the outcomes of the first series of robot-assisted pudendal nerve release (RPNR). PATIENTS AND METHODS: 32 patients, who were treated with RPNR in our centre between January 2016 and July 2021, were recruited. Following the medial umbilical ligament identification, the space between this ligament and the ipsilateral external iliac pedicle is progressively dissected to identify the obturator nerve. The dissection medial to this nerve identifies the obturator vein and the arcus tendinous of the levator ani, which is cranially inserted into the ischial spine. Following the cold incision of the coccygeous muscle at the level of the spine, the sacrospinous ligament is identified and incised. The pudendal trunk (vessels and nerve) is visualized, freed from the ischial spine and medially transposed. RESULTS: The Median duration of symptoms was 7 (5, 5-9) years. The median operative time was 74 (65-83) minutes. The median length of stay was 1 (1-2) days. There was only a minor complication. At 3 and 6 months after surgery, a statistically significant pain reduction has been encountered. Furthermore, the Pearson correlation coefficient reported a negative relationship between the duration of pain and the improvement in NPRS score, - 0.81 (p = 0.01). CONCLUSIONS: RPNR is a safe and effective approach for the pain resolution caused by PNE. Timely nerve decompression is suggested to enhance outcomes.

Right laparoscopic pudendal release + neurostimulator prosthesis (LION procedure) in pudendal neuralgia.

AIM: Pudendal neuralgia is a highly disabling entity with complex diagnostic and controversial treatment results. Surgical neurolysis has been shown to be the most effective treatment. Sacral root neurostimulation or posterior tibial nerve stimulation are used to rescue patients who either have not responded to surgery or have worsened after an initial improvement. METHODS: Given the excellent visualization of the pudendal nerve during laparoscopic pudendal release, we propose to combine this procedure with neurostimulation, taking advantage of the possibility of in situ placement of the electrode. The abdominal cavity is accessed laparoscopically through four ports, and after identifying and releasing the pudendal nerve a neurostimulation electrode is placed next to the nerve and is connected to a generator located in a subcutaneous pocket. RESULTS: This procedure has been performed in one patient with a satisfactory result. CONCLUSIONS: Laparoscopic pudendal release with neurostimulator prosthesis is an experimental technique that can be promising for the treatment of pudendal neuralgia.

Pudendal Neuromodulation is Feasible and Effective After Pudendal Nerve Entrapment Surgery.

BACKGROUND: Patients with intractable pain in the pudendal nerve distribution may benefit from pudendal neuromodulation; however, some may have previously undergone pudendal nerve entrapment surgery (PNES), potentially altering nerve anatomy and function. AIM: We examined pudendal neuromodulation outcomes in patients with prior PNES. METHODS: Patients with a history of PNES and quadripolar, tined pudendal lead placement for urogenital pain were reviewed. Symptoms and outcomes were collected from existing medical records. OUTCOMES: Patients with pudendal neuromodulation and prior PNES were compared to patients with no prior PNES who had pudendal lead placement. RESULTS: Fifteen patients with a history of 1, 2, or 3 prior PNES (n = 13, 1, and 1, respectively) were evaluated. Most (10; 67%) were female, with bilateral pain (9; 60%), and symptoms of 5-26 years. After trialing the lead, bladder symptoms and pain were improved in 8 of 12 and 9 of 14 patients, respectively, and 80% of patients (12/15) underwent permanent generator implantation. When prior PNES patients were compared to those with no prior PNES (n = 43), gender (67% vs 77% female; P = .50) and age (median 63 vs 58 years; P = .80), were similar; however, BMI differed (mean 24 vs 29; P = .008) and a lower proportion (12/15; 80% vs 42/43; 98%; P = .049) had generator implantation. Importantly, median lead implant time (48 vs 50 minutes; P = .65) did not differ between the 2 groups. CLINICAL IMPLICATIONS: Pudendal neuromodulation has the potential to provide pain relief for a very difficult-to-treat population; furthermore, it does not appear that prior PNES surgery made lead placement significantly more challenging. STRENGTHS & LIMITATIONS: Study strengths include being a tertiary referral center for urogenital pain and having a single surgeon perform all procedures in a regimented way. Limitations include the retrospective study design, small sample size and various approaches to PN CONCLUSION: Chronic pudendal neuromodulation can be a viable option even after prior PNES. Kristen M. Meier, Patrick M. Vecellio, Kim A. Killinger, Judith A. Boura, Kenneth M. Peters. Pudendal Neuromodulation is Feasible and Effective After Pudendal Nerve Entrapment Surgery. J Sex Med 2022;19:995-1001.

Surgical management of pudendal nerve entrapment after sacrospinous ligament fixation.

OBJECTIVE: To analyse the efficacy of sacrospinous ligament (SSL) suture removal on the reduction of pain symptoms in the case of suspected pudendal nerve entrapment after sacrospinous ligament fixation (SSLF). DESIGN: Retrospective cohort study. SETTING: Tertiary referral centre, the Netherlands. POPULATION: A cohort of 21 women having their SSLF sutures removed because of SSLF-related pain symptoms. METHODS: Clinical record review. MAIN OUTCOME MEASURES: The primary outcome was reduction of pain after SSL suture removal. Secondary outcome measures were time interval between suture placement and suture removal, complete suture removal, adverse events and recurrence of pelvic organ prolapse (POP). RESULTS: A total of 21 women underwent SSL suture removal for severe and/or persistent pain, which was confirmed on clinical examination: 95% of the women (20/21) reported pain reduction after suture removal, and 57% reported complete pain relief. The time interval between suture placement and suture removal was at a median of 414 days (range 8-1855 days). Sutures could be completely removed in 86% of cases (18/21). One woman had excessive blood loss (520 ml) without blood transfusion. At 6-8 weeks after surgery, 10% of the women (2/21) had renewed symptomatic POP, stage ≥ 2, for which additional POP surgery was indicated. CONCLUSIONS: When performed by an experienced clinician, SSL suture removal is feasible and efficacious, with low morbidity. In addition, the risk of recurrent POP in the short term appeared to be low. TWEETABLE ABSTRACT: The surgical removal of sacrospinous ligament sutures is safe and efficacious for pain relief, even remote from initial placement.

Is pudendal nerve entrapment a potential cause for weak ejaculation?

Ejaculatory dysfunction is one of the most common complaints of patients with sexual disorders. While it encompasses several ejaculatory disorders, weak ejaculation is seldom described in the literature. Since the pudendal nerve is the main nerve of ejaculation, we aim to hypothesize that pudendal nerve entrapment could be a cause of weak ejaculation, and that pudendal nerve release could contribute to the improvement of the ejaculatory stream. We presented two cases suffering from a weak ejaculatory stream and sensation of incomplete semen emptying, accompanied with clinical features of pudendal nerve entrapment. Both cases improved after pudendal nerve block and then laparoscopic transperitoneal pudendal release, with a sustained amelioration of the ejaculatory stream after 3 weeks of surgery. Pudendal canal entrapment is therefore a potentially curable cause for weak ejaculation.

Pudendal nerve block: a safe, simple and effective approach in surgical proctological patients.

BACKGROUND: Pudendal nerve block (PNB) is commonly used in pudendal neuralgia (PN) and, as anesthesiological technique, in obstetrical and urological procedures. The purpose of this retrospective study was to compare the efficacy of PNB with other anesthesiolocal techniques in proctological surgery. METHODS: A total of 362 patients were seen from a 22-month-time interval. Surgical indication was placed after a conservative therapy. Seventy-eight patients underwent surgery: 42 with spinal anesthesia with PNB and 36 with PNB alone according to their anatomical characteristics. All the patients underwent PNB in lithotomy position and with a perirectal approach. The success rate of PNB was evaluated in postoperative pain control with the VAS score, after the first and the second evacuation. The follow-up also included a third check on the seventh day after surgery. RESULTS: In postoperative period, the mean VAS score found after the first evacuation in patients undergoing PNB was 2.66, after the second evacuation was 1.55, while the VAS score on the seventh day was 0.38. The mean VAS score in the group who underwent spinal anesthesia and PNB were respectively 3.71 and 1.80 after the first and second evacuation. The VAS score calculated on the seventh day was 0.50. There were no statistically significant differences in the VAS score between the 2 groups (P>0.05). CONCLUSIONS: PNB may be a valid alternative to spinal anesthesia in proctological patients. PNB has proven to be both safe and effective technique.

Post-traumatic double crush pudendal nerve entrapment syndrome after fracture of the pelvis: A case report.

Pudendal syndrome is primarily characterized by stress urinary incontinence, dysuria, sexual arousal syndrome, painful erections, and anal incontinence. The syndrome occurs when the pudendal nerve or one of its branches is compressed, stretched, or injured. Double crush is the compression of a peripheral nerve at two or more separate areas with various signs and symptoms. We, herein, aimed to introduce the case of a 42-year-old male who underwent the distal release procedure due to the diagnosis of "double crush pudendal syndrome" following a proximal release surgery previously performed elsewhere. The patient's history revealed a pelvic fracture with urethral injury 27 years ago. Throughout the years, the patient had been evaluated by various medical disciplines and undergone several treatments. In 2017, an orthopedic surgeon performed proximal pudendal nerve release using transgluteal approach, and then rectal pain and defecation complaints relieved. However, in 2019, the patient was referred to our clinic because of the persistence of erection and perineal complaints after the proximal pudendal nerve release. Based on a detailed clinical and laboratory assessment, the diagnosis of double crush neuropathy was established, and distal release of the pudendal nerve using transperineal approach was performed. To determine the efficiency of the surgical treatment, International Index of Erectile Function (IIEF) and Quality of Erection Questionnaire (QAQ) tests were used preoperatively and at the first postoperative year. Furthermore, to assess the perineal pain, erection pain, and pain during intercourse Visual Analog Scale (VAS) was used. The erectile dysfunction improved from the severe degree (9 points) to the mild degree (22 points) postoperatively. The patient's general and sexual satisfaction scores, and erection quality score improved compared to the preoperative baseline. According to VAS, the perineal pain, erectile pain,and pain during intercourse decreased postoperatively. (from 7 to 2 out of 10, from 8 to 3 out of 10, from 7 to 2 out of 10, respectively). When perineal and sexual complaints are encountered following pelvic trauma, the pudendal nerve-related problems, especially double crush syndrome, should be kept in mind in differential diagnosis. A multidisciplinary approach must be established in order to avoid any delay in diagnosis and treatment. Surgical intervention may provide a significant improvement in clinical and functional status.

Pudendal Neurolysis: 6-Step Laparoscopic Approach.

OBJECTIVE: To demonstrate the safety and feasibility of the laparoscopic approach to perform pudendal neurolysis in a case of pudendal nerve entrapment syndrome [1-3]. DESIGN: A video tutorial that highlights the laparoscopic steps to performing pudendal neurolysis, with a focus on the main anatomic landmarks [4,5]. SETTING: A tertiary care regional hospital. INTERVENTIONS: This video shows a 6-step approach to laparoscopic pudendal neurolysis for the treatment of pudendal nerve entrapment between the sacrospinous and sacrotuberous ligaments [2,6-8]. Step 1: Identification of the umbilical artery. Step 2: Dissection and development of the lateral paravesical space until the pelvic floor. Step 3: Identification of the arcus tendineus of the endopelvic fascia. Step 4: Identification of the ischial spine and the sacrospinous ligament covered by the coccygeus muscle. Step 5: Coagulation and section of the coccygeus muscle and the sacrospinous ligament. Step 6: Medialization of the pudendal nerve until its entrance into the Alcock canal. CONCLUSION: This video demonstrates the safety, feasibility, and reproducibility of laparoscopic pudendal neurolysis in 6 steps. A minimally invasive approach is adequate to treat the pudendal compression until the Alcock canal [2].

Laparoscopic treatment of pudendal nerve and artery entrapment improves erectile dysfunction in healthy young males.

Erectile dysfunction (ED) is increasingly becoming more common in young healthy males and is attributed mainly to psychogenic causes in these patients. Recent studies have reported that ED could be secondary to pudendal nerve or artery entrapment. This perspective assessed the efficacy of laparoscopic pudendal nerve and artery decompression in young patients suffering from refractory ED, associated to a pudendal nerve entrapment syndrome. After excluding patients with psychological ED and venous leakage, five young male patients with a history of both ED and pudendal nerve entrapment syndrome diagnosed based on the Nantes criteria were recruited. Pudendal nerve and artery release was performed using a laparoscopic transperitoneal approach. International Index for Erectile Function (IIEF-5) and erectile hardness score (EHS) improved significantly in all patients, 3 months after surgery. Pudendal nerve and artery entrapment could be therefore a reversible cause of ED in young healthy males, and its treatment by laparoscopic pudendal nerve and artery decompression seems to be safe and effective.

Pudendal Neurolysis by Laparoscopy.

STUDY OBJECTIVE: To show how pudendal neurolysis can be managed safely with a laparoscopic approach. DESIGN: Stepwise demonstration of the technique with narrated video footage. SETTING: The pudendal nerve is formed from spinal roots at levels S2, S3, and S4. It passes through the pelvis parallel to the pudendal vein and artery. This nerve exits the pelvis between the sacrospinous and sacrotuberous ligaments then passes through Alcock's canal. It can be compressed and responsible for pain in the gluteal and perineal regions. After confirmation of the diagnosis by positive analgesic block with computed tomography infiltration of the pudendal nerve, surgical decompression may be considered. The usual access procedures are the transglutal and transischiorectal ways. INTERVENTIONS: This video shows a total laparoscopic approach for a right pudendal neurolysis. It is a step-by-step didactic video. This technique of decompression of the right pudendal nerve by laparoscopy by means of dissection of the ischiorectal fossa along the right internal obturator muscle, after visualization of the obturator vessels and identification of the pudendal nerve, allowed the section of the right sacrospinous ligament and complete removal with repositioning of the nerve in its path. The nerve was followed until it passed freely through Alcock's canal. The procedure went well and without complications, with clinical improvement on waking up. CONCLUSION: Pudendal nerve neurolysis by laparoscopic technique is a reproducible and safe method for treating pudendal neuralgia, allowing good visualization and dissection of the entire pelvis toward the ischiorectal fossa.

Endoscopic trans gluteal minimal-invasive approach for nerve liberation (ENTRAMI technique) in case of pudendal and/or cluneal neuralgia by entrapment: One-year follow-up.

BACKGROUND: Chronic neuropathic perineal pain syndrome is a collective term that encompasses several diagnoses. In patients where the neuropathic pain syndrome is caused by pudendal or cluneal nerve entrapment, surgical release can be proposed if other measures have failed. The aim of this study is to evaluate the clinical outcome of patients suffering from pudendal and/or cluneal nerve entrapment at 1 year after this minimal invasive surgery, which is based on the open trans gluteal approach who has proven its efficacy compared to medical treatment in a randomized control trial. METHODS: Patients eligible for inclusion had chronic perineal neuropathic pain for at least 3 months in the area served by the pudendal and/or cluneal nerve, refractory to conservative measurements. Patients met all five of the Nantes criteria. RESULTS: Fifteen patients underwent the ENTRAMI technique. At 1 year after surgery, overall reduction of the average maximal Numeric Pain rating Scale (NPRS-score) was from 9 (range, 7-10) at baseline to 5 (range, 0-10; P-value <.05). At 1 year 73% of patients declared to have a "good treatment response" (patient global impression of change [PGIC] >30%) and optimal treatment response (PGIC ≥90%) was found in 40% (P-value <.05). No complications were recorded. CONCLUSION: This study clearly shows that the technique is feasible with promising long-term results in a difficult to manage patient group.

A minimally invasive, endoscopic transgluteal procedure for pudendal nerve and inferior cluneal nerve neurolysis in case of entrapment: 3- and 6-month results. The ENTRAMI technique for neurolysis.

BACKGROUND: Pudendal and cluneal nerve entrapment can cause a neuropathic pain syndrome in the sensitive areas innervated by these nerves. Recently, a new endoscopic minimal invasive approach for pudendal and inferior cluneal nerve neurolysis has been published in a cadaver study. The aim of our study was to describe the feasibility of this new approach and to evaluate the clinical outcome. METHODS: Fifteen patients underwent the ENTRAMI technique. The Numeric Pain Rating Scale (NPRS) and Patient Global Impression of Change (PGIC) were recorded at baseline and at 3 and 6 months after surgery. RESULT: The average duration of intervention (skin to skin) was 139 min (range 50-270 min) for bilateral pudendal neurolysis and/or cluneal neurolysis and 113 min (range 100-130 min) for unilateral pudendal and/or cluneal neurolysis. No perioperative blood loss occurred. At 3 months, 50% of patients declared a more than 30% improvement of their PGIC, increasing to 57% at 6 months; 31% reported more than 90% improvement of PGIC at 6 months. Overall reduction of the average maximal NPRS score was from 9 (range 7-10) to 6 at 3 months (range 0-10; p value < 0.05) and to 5 at 6 months (range 0-10; p value < 0.05). There were no postoperative complications. CONCLUSIONS: The ENTRAMI technique is feasibly in patients suffering from pudendal and/or cluneal neuralgia and preliminary results are promising. CLINICAL TRIAL NUMBER: NCT03883178.

Successful Treatment of Penile Numbness and Erectile Dysfunction Resulting From Pudendal Nerve Entrapment.

Pudendal nerve decompression surgery has not been studied or reported for the treatment of penile numbness in the absence of pain. Herein, we report a case of a male patient with chronic numbness of the penis and erectile dysfunction in the absence of pelvic pain who was found to have pudendal nerve entrapment. This patient was treated with surgical decompression of the pudendal nerves that resulted in the return of genital sensation and erections. Thus, we propose that pudendal nerve entrapment may be considered as a cause of penile numbness and that pudendal nerve decompression surgery in these patients may be effective.

Initial experience of CT-guided pulsed radiofrequency ablation of the pudendal nerve for chronic recalcitrant pelvic pain.

AIM: To evaluate initial experience with computed tomography (CT)-guided pulsed radiofrequency ablation (pRFA) of the pudendal nerve in cases of recalcitrant neuropathic pelvic pain. Endpoints include technical feasibility, safety, and efficacy of therapy. MATERIALS AND METHODS: Ten patients who underwent pRFA ablation for neuropathic pudendal nerve pain during the trial period were followed for response to treatment for 6 months. Each patient was treated with pRFA under CT-guidance with concurrent perineural injection of anaesthetic and/or corticosteroid. Pain scores were then measured using a numeric rating scale at fixed intervals up to 6 months. RESULTS: All procedures were considered technically successful with no immediate complications. pRFA demonstrated improved duration of pain improvement compared to the most recent perineural injection (p=0.0195), but not compared to the initial injection (p=0.64). Reported pain scores were lower with pRFA than with both the first and most recent injection but this did not reach statistical significance (p=0.1094 and p=0.7539, respectively). CONCLUSION: Overall, pRFA of the pudendal nerve using CT-guidance can be a safe and effective therapy. This technique provides direct visualisation of the nerve to maximise safety and efficacy while offering a novel form of therapy for patients with chronic, recalcitrant pelvic pain.

Vascular Entrapment of Both the Sciatic and Pudendal Nerves Causing Persistent Sciatica and Pudendal Neuralgia.

STUDY OBJECTIVE: To demonstrate the laparoscopic approach to malformed branches of the vessels entrapping the nerves of the sacral plexus. DESIGN: A step-by-step explanation of the surgery using video (educative video) (Canadian Task force classification II). The university's Ethics Committee ruled that approval was not required for this video. SETTING: Kocaeli Derince Education and Research Hospital, Kocaeli, Turkey. PATIENT: A 26-year-old patient who had failed medical therapy and presented with complaints of numbness and burning pain on the right side of her vagina and pain radiating to her lower limbs for a period of approximately 36 months. INTERVENTION: The peritoneum was incised along the external iliac vessels, and these vessels were separated from the iliopsoas muscle on the right side of the pelvis. The laparoscopic decompression of intrapelvic vascular entrapment was performed at 3 sites: the lumbosacral trunk, sciatic nerve, and pudendal nerve. The aberrant dilated veins were gently dissected from nerves, and then coagulated and cut with the LigaSure sealing device (Medtronic, Minneapolis, Minn). MEASUREMENTS AND MAIN RESULTS: The operation was completed successfully with no complications, and the patient was discharged from the hospital 24 hours after the operation. At a 6-month follow-up, she reported complete resolution of dyspareunia and sciatica (visual analog scale score 1 of 10). CONCLUSION: A less well-known cause of chronic pelvic pain is compression of the sacral plexus by dilated or malformed branches of the internal iliac vessels. Laparoscopic management of vascular entrapment of the sacral plexus has been described by Possover et al [1,2] and Lemos et al [3]. This procedure appears to be feasible and effective, but requires significant experience and familiarity with laparoscopy techniques and pelvic nerve anatomy.