Surgical treatment of chronic pain after inguinal hernia repair

Somatosensory Outcomes Following Re-Surgery in Persistent Severe Pain After Groin Hernia Repair: A Prospective Observational Study

Purpose

After groin hernia repair (globally more than 20 million/year) 2-4% will develop persistent severe pain (PSPG). Pain management is challenging and may require multimodal interventions, including re-surgery. Quantitative somatosensory testing (QST) is an investigational psychophysiological tool with the potential to uncover the pathophysiological mechanisms behind the pain, ie, revealing neuropathic or inflammatory components. The primary objective was to examine and describe the underlying pathophysiological changes in the groin areas by QST before and after re-surgery with mesh removal and selective neurectomy.

Patients and Methods

Sixty patients with PSPG scheduled for re-surgery and with an inflammatory "component" indicated by blunt pressure algometry were examined in median (95% CI) 7.9 (5.8-11.5) months before and 4.0 (3.5-4.6) months after re-surgery. The QST-analyses included standardized assessments of cutaneous mechanical/thermal detection and pain thresholds. Suprathreshold heat stimuli were applied. Deep tissue sensitivity was tested by pressure algometry. Testing sites were the groin areas and the lower arm. Before/after QST data were z-transformed.

Results

Re-surgery resulted in median changes in rest, average, and maximal pain intensity scores of -2.0, -2.5, and -2.0 NRS (0/10) units, respectively (P = 0.0001), and proportional increases in various standardized functional scores (P = 0.0001). Compared with the control sites, the cutaneous somatosensory detection thresholds of the painful groin were increased before re-surgery and increased further after re-surgery (median difference: 1.28 z-values; P = 0.001), indicating a successive post-surgical loss of nerve fiber function ("deafferentation"). Pressure algometry thresholds increased after re-surgery (median difference: 0.30 z-values; P = 0.001).

Conclusion

In this subset of patients with PSPG who underwent re-surgery, the procedure was associated with improved pain and functional outcomes. While the increase in somatosensory detection thresholds mirrors the surgery-induced cutaneous deafferentation, the increase in pressure algometry thresholds mirrors the removal of the deep "pain generator". The QST-analyses are useful adjuncts in mechanism-based somatosensory research.

Risks of therapeutic versus prophylactic neurectomies

INTRODUCTION

Neuralgia due to a peripheral nerve injury may result in chronic pain, requiring a therapeutic surgical neurectomy. Meanwhile, some neurectomies are performed prophylactically, such as during inguinal mesh removal. Outcomes and risks associated with neurectomies are largely unknown despite consensus panels recommending them.

METHODS

All patients who underwent neurectomy 2013-2020 were analyzed. Data collection included demographics, preoperative symptoms, and postoperative outcomes. Indications for neurectomy were categorized as "therapeutic" if the patient had preoperative neuralgia or "prophylactic" if neurectomy was deemed necessary intra-operatively.

RESULTS

66 patients underwent 80 operations and a total of 122 neurectomies. On average, 1.5 neurectomies were performed per operation. Therapeutic neurectomies were performed in 42 (64%) patients and prophylactic in 34 (52%). The most commonly transected nerve was the ilioinguinal nerve. Average preoperative pain score was 5.8/10. On paired analysis, there was a significant reduction in pain after prophylactic neurectomy (2.5 points, p = 0.002) but not after therapeutic neurectomy. None of the nerves transected prophylactically had postoperative neuralgia, whereas 35% of the nerves transected therapeutically resulted in persistent or recurrent neuralgia (p < 0.001). To treat this, 21% required only nerve blocks and 9% required ablation or reoperative neurectomy. Three patients had complex regional pain syndrome (CRPS), a severe complication; all three were diagnosed with chronic pain syndrome pre-operatively.

DISCUSSION

We demonstrate that prophylactic neurectomy is largely safe. In contrast, a therapeutic neurectomy had a 35% risk of persistent or recurrent neuralgia, 9% required additional ablative or reoperative neurectomy. Three patients advanced from chronic pain syndrome to CRPS. We recommend the decision to perform a neurectomy be judicious and selective, especially in patients with known chronic pain syndrome. Prior to planning surgical neurectomy, other less invasive modalities should be exhausted and patients should be aware of its risks.

Robotic mesh explantation (RoME): a novel approach for patients with chronic pain following hernia repair

BACKGROUND

Post-herniorrhaphy pain is common with an estimated 8-10% incidence of mesh-related complications, requiring mesh explantation in up to 6% of cases, most commonly after inguinal hernia repairs. Reoperation for mesh explantation poses a surgical challenge due to adhesions, scarring and mesh incorporation to the surrounding tissues. Robotic technology provides a versatile platform for enhanced exposure to tackle these complex cases. We aim to share our experience with a novel robotic approach to address these complex cases.

METHODS

A descriptive, retrospective analysis of patients undergoing a robotic mesh explantation (RoME) for mesh-related chronic pain, or recurrent ventral hernia by two surgeons between the period of March 2016 and January of 2020. The patients were evaluated for resolution of mesh related abdominal pain as well as early post-operative complications. RoME was performed with concomitant hernia repair in cases of recurrences.

RESULTS

Twenty-nine patients underwent a robotic mesh explantation (RoME) for mesh-related chronic pain, or recurrent ventral hernia between March 2016 and January of 2020. Nineteen patients (65.5%) had a prior inguinal hernia repair and 10 patients (34.5%) had a prior ventral hernia repair. Indications for mesh removal included chronic pain with or without hernia recurrence. Seventeen patients (58.6%) reported improvement or resolution of pain postoperatively (63% with a prior inguinal hernia repair and 50% of patients with a prior ventral hernia repair). Five patients (17.2%) required mesh reinforcement after explantation. Nineteen patients (65.5%) underwent mesh explantation with primary fascial closure or no mesh reinforcement. The mean follow-up was 36.4 days. The most common postoperative complication was seroma formation (6.8%), with one reported recurrence (3.4%).

CONCLUSION

Robotic mesh explantation in challenging cases due to the effect of chronic scarring, adhesions and mesh incorporation to the surrounding tissues is safe and provides an advantageous platform for concomitant hernia repair in these complex cases.

Surgical treatment for chronic pain after inguinal hernia repair: a systematic literature review

PURPOSE

Chronic postoperative inguinal pain (CPIP) is a frequent complication after inguinal surgery with a significant decrease in quality of life. There is still no clear algorithm regarding surgical treatment. The aim of this systematic review was to provide an overview on the principles and outcome of surgical interventions for CPIP based on the available literature.

MATERIALS AND METHODS

A literature search was performed using the databases PubMed and SCOPUS following the PRISMA statement. Used Mesh terms and keywords were "postoperative pain," "chronic pain," "inguinal hernia," and "surgical treatment." All articles were reviewed regarding surgical technique and outcome. MINORS criteria for the assessment of the methodological quality of non-randomized surgical studies were applied.

RESULTS

Eighteen articles, of which 17 cohort studies and one randomized controlled trial (RCT), described the surgical management of CPIP. Selective as well as triple neurectomy, often in combination with mesh removal and removal of suture material, was performed. Success rate, defined as significant or complete relief of pain, ranged from 33 until 100%, with most articles reaching success rates above 70%, showing a clear advantage of surgical therapy for chronic pain.

CONCLUSIONS

The use of surgical triple neurectomy seems effective and helpful in a high percentage of patients with CPIP. Surgical treatment should only be considered after adequate preoperative diagnostic evaluation of which the dermatome sensory mapping seems a useful tool for detailed neurophysiological assessment of patients with persistent post-herniorrhaphy pain undergoing remedial neurectomy.

A Simplified clinical algorithm for standardized surgical treatment of chronic pain after inguinal hernia repair: A quality assessment study

BACKGROUNDS

The optimal surgical strategy for the treatment of chronic pain after inguinal hernia repair is controversial and based on relatively weak evidence. The purpose of this study was to analyze pain-related functional impairment using a simplified clinical treatment algorithm for a standardized surgical treatment. The algorithm was predefined, and the indication to operate was based on strict criteria.

METHODS

This was a prospective, non-controlled, explorative study. The pain operation was either open triple neurectomy with total mesh removal or laparoscopic retroperitoneal triple neurectomy. A clinically relevant postoperative change was defined as ⩾25% change from the baseline level. Primary outcome was pain-related impairment of physical function using the Activity Assessment Scale. Secondary outcomes included Individual Patient-Reported Outcome Measures, Hospital Anxiety and Depression Scale, and PainDETECT Questionnaire.

RESULTS

A total of 240 patients were referred (2016-2019). Sixty-six patients were included for the analysis. A total of 25% of referred patients were offered a pain operation. Follow-up was a median 3 months (range: 3-13). Activity Assessment Scale scores were clinically relevant improved in 43 patients (68%), not clinically relevant different in 19 (30%), and clinically relevant worsened in one (2%). Secondary outcome scores were all significantly improved (P < 0.05) except for the risk of postoperative depression (P = 0.092). Fifty-one patients (77%) reported that chronic groin pain was reduced after the operation.

CONCLUSIONS

Pain-related functional impairment was improved with clinical relevance in roughly 70% of patients through a simplified clinical algorithm for surgical treatment of severe chronic pain after an inguinal hernia repair.

Chronic postoperative inguinal pain: A narrative review

Inguinodynia or chronic postoperative inguinal pain is a growing problem between patients who undergo surgical repair of an inguinal hernia. The change in results measurement proposed by many authors towards Patient Reported Outcome Measurement has underlined the importance of chronic postoperative inguinal pain, because of the great limitations in everyday life and the huge socioeconomic impact that it causes. In this article a narrative review of the available literature in PUBMED, EMBASE and Cochrane Library is performed and the most relevant aspects about epidemiology, etiology prevention, diagnosis and treatment of chronic postoperative inguinal pain are discussed. A new management algorithm is also proposed. The variability in its incidence and clinical presentation makes diagnosis of chronic postoperative inguinal pain a very challenging issue. There is no standardized therapy and an adequate etiological diagnosis is key point for a successful treatment. There are many treatment options that have to be sequentially used and adjusted to each patient and their clinical features.

Pain during and after-hernioplasty in raquidian or locorregional anesthesia by locking peripheral nerves

PURPOSE

To analyze pain scores after surgery in a group of patients submitted to inguinal hernia repair under peripheral nerve block with local or spinal anesthesia.

METHODS

Fifty patients were divided into two groups (both with 25 patients each). In the first group the patients were submitted to herniorrhaphy under peripheral block and local anesthesia (LG) and in the other group the patients were submitted to the same procedure under spinal anesthesia (RG). The pain was assessed using the international visual analog pain scale at four different moments. The analysis cost of the procedure was performed using the hospital's average final cost, without including medical expenses.

RESULTS

The groups were homogeneous in relation to the epidemiological and clinical features. There was no significant difference between the pain in the intraoperative period and in the return visit for both groups (p = 0.17 and p = 0.18). In the immediate postoperative period, both groups reported no pain at all. In general, the RG reported a greater pain score (16% for RG and 12% for LG). Complications were more frequent in patients submitted to spinal anesthesia (40% versus 8%) (p = 0.008). The surgical time was higher in the LG (39.3 ± 9.2 min) versus (28.7 ± 7.5 min) (p = 0.01). The average final cost of the procedure was US$ 100.98 for the LG and US$ 166.19 for the RG (p = 0.00).

CONCLUSION

The inguinal hernioplastia under local anesthesia plus sedation is a safe method, with a low incidence of complications, great acceptance by patients and less expensive.

International guidelines for groin hernia management

INTRODUCTION

Worldwide, more than 20 million patients undergo groin hernia repair annually. The many different approaches, treatment indications and a significant array of techniques for groin hernia repair warrant guidelines to standardize care, minimize complications, and improve results. The main goal of these guidelines is to improve patient outcomes, specifically to decrease recurrence rates and reduce chronic pain, the most frequent problems following groin hernia repair. They have been endorsed by all five continental hernia societies, the International Endo Hernia Society and the European Association for Endoscopic Surgery.

METHODS

An expert group of international surgeons (the HerniaSurge Group) and one anesthesiologist pain expert was formed. The group consisted of members from all continents with specific experience in hernia-related research. Care was taken to include surgeons who perform different types of repair and had preferably performed research on groin hernia surgery. During the Group's first meeting, evidence-based medicine (EBM) training occurred and 166 key questions (KQ) were formulated. EBM rules were followed in complete literature searches (including a complete search by The Dutch Cochrane database) to January 1, 2015 and to July 1, 2015 for level 1 publications. The articles were scored by teams of two or three according to Oxford, SIGN and Grade methodologies. During five 2-day meetings, results were discussed with the working group members leading to 136 statements and 88 recommendations. Recommendations were graded as "strong" (recommendations) or "weak" (suggestions) and by consensus in some cases upgraded. In the Results and summary section below, the term "should" refers to a recommendation. The AGREE II instrument was used to validate the guidelines. An external review was performed by three international experts. They recommended the guidelines with high scores. The risk factors for inguinal hernia (IH) include: family history, previous contra-lateral hernia, male gender, age, abnormal collagen metabolism, prostatectomy, and low body mass index. Peri-operative risk factors for recurrence include poor surgical techniques, low surgical volumes, surgical inexperience and local anesthesia. These should be considered when treating IH patients. IH diagnosis can be confirmed by physical examination alone in the vast majority of patients with appropriate signs and symptoms. Rarely, ultrasound is necessary. Less commonly still, a dynamic MRI or CT scan or herniography may be needed. The EHS classification system is suggested to stratify IH patients for tailored treatment, research and audit. Symptomatic groin hernias should be treated surgically. Asymptomatic or minimally symptomatic male IH patients may be managed with "watchful waiting" since their risk of hernia-related emergencies is low. The majority of these individuals will eventually require surgery; therefore, surgical risks and the watchful waiting strategy should be discussed with patients. Surgical treatment should be tailored to the surgeon's expertise, patient- and hernia-related characteristics and local/national resources. Furthermore, patient health-related, life style and social factors should all influence the shared decision-making process leading up to hernia management. Mesh repair is recommended as first choice, either by an open procedure or a laparo-endoscopic repair technique. One standard repair technique for all groin hernias does not exist. It is recommended that surgeons/surgical services provide both anterior and posterior approach options. Lichtenstein and laparo-endoscopic repair are best evaluated. Many other techniques need further evaluation. Provided that resources and expertise are available, laparo-endoscopic techniques have faster recovery times, lower chronic pain risk and are cost effective. There is discussion concerning laparo-endoscopic management of potential bilateral hernias (occult hernia issue). After patient consent, during TAPP, the contra-lateral side should be inspected. This is not suggested during unilateral TEP repair. After appropriate discussions with patients concerning results tissue repair (first choice is the Shouldice technique) can be offered. Day surgery is recommended for the majority of groin hernia repair provided aftercare is organized. Surgeons should be aware of the intrinsic characteristics of the meshes they use. Use of so-called low-weight mesh may have slight short-term benefits like reduced postoperative pain and shorter convalescence, but are not associated with better longer-term outcomes like recurrence and chronic pain. Mesh selection on weight alone is not recommended. The incidence of erosion seems higher with plug versus flat mesh. It is suggested not to use plug repair techniques. The use of other implants to replace the standard flat mesh in the Lichtenstein technique is currently not recommended. In almost all cases, mesh fixation in TEP is unnecessary. In both TEP and TAPP it is recommended to fix mesh in M3 hernias (large medial) to reduce recurrence risk. Antibiotic prophylaxis in average-risk patients in low-risk environments is not recommended in open surgery. In laparo-endoscopic repair it is never recommended. Local anesthesia in open repair has many advantages, and its use is recommended provided the surgeon is experienced in this technique. General anesthesia is suggested over regional in patients aged 65 and older as it might be associated with fewer complications like myocardial infarction, pneumonia and thromboembolism. Perioperative field blocks and/or subfascial/subcutaneous infiltrations are recommended in all cases of open repair. Patients are recommended to resume normal activities without restrictions as soon as they feel comfortable. Provided expertise is available, it is suggested that women with groin hernias undergo laparo-endoscopic repair in order to decrease the risk of chronic pain and avoid missing a femoral hernia. Watchful waiting is suggested in pregnant women as groin swelling most often consists of self-limited round ligament varicosities. Timely mesh repair by a laparo-endoscopic approach is suggested for femoral hernias provided expertise is available. All complications of groin hernia management are discussed in an extensive chapter on the topic. Overall, the incidence of clinically significant chronic pain is in the 10-12% range, decreasing over time. Debilitating chronic pain affecting normal daily activities or work ranges from 0.5 to 6%. Chronic postoperative inguinal pain (CPIP) is defined as bothersome moderate pain impacting daily activities lasting at least 3 months postoperatively and decreasing over time. CPIP risk factors include: young age, female gender, high preoperative pain, early high postoperative pain, recurrent hernia and open repair. For CPIP the focus should be on nerve recognition in open surgery and, in selected cases, prophylactic pragmatic nerve resection (planned resection is not suggested). It is suggested that CPIP management be performed by multi-disciplinary teams. It is also suggested that CPIP be managed by a combination of pharmacological and interventional measures and, if this is unsuccessful, followed by, in selected cases (triple) neurectomy and (in selected cases) mesh removal. For recurrent hernia after anterior repair, posterior repair is recommended. If recurrence occurs after a posterior repair, an anterior repair is recommended. After a failed anterior and posterior approach, management by a specialist hernia surgeon is recommended. Risk factors for hernia incarceration/strangulation include: female gender, femoral hernia and a history of hospitalization related to groin hernia. It is suggested that treatment of emergencies be tailored according to patient- and hernia-related factors, local expertise and resources. Learning curves vary between different techniques. Probably about 100 supervised laparo-endoscopic repairs are needed to achieve the same results as open mesh surgery like Lichtenstein. It is suggested that case load per surgeon is more important than center volume. It is recommended that minimum requirements be developed to certify individuals as expert hernia surgeon. The same is true for the designation "Hernia Center". From a cost-effectiveness perspective, day-case laparoscopic IH repair with minimal use of disposables is recommended. The development and implementation of national groin hernia registries in every country (or region, in the case of small country populations) is suggested. They should include patient follow-up data and account for local healthcare structures. A dissemination and implementation plan of the guidelines will be developed by global (HerniaSurge), regional (international societies) and local (national chapters) initiatives through internet websites, social media and smartphone apps. An overarching plan to improve access to safe IH surgery in low-resource settings (LRSs) is needed. It is suggested that this plan contains simple guidelines and a sustainability strategy, independent of international aid. It is suggested that in LRSs the focus be on performing high-volume Lichtenstein repair under local anesthesia using low-cost mesh. Three chapters discuss future research, guidelines for general practitioners and guidelines for patients.

CONCLUSIONS

The HerniaSurge Group has developed these extensive and inclusive guidelines for the management of adult groin hernia patients. It is hoped that they will lead to better outcomes for groin hernia patients wherever they live. More knowledge, better training, national audit and specialization in groin hernia management will standardize care for these patients, lead to more effective and efficient healthcare and provide direction for future research.

Mesh Removal and Selective Neurectomy for Persistent Groin Pain Following Lichtenstein Repair

BACKGROUND

Some patients with persistent inguinodynia following a Lichtenstein hernia repair fail all non-surgical treatments. Characteristics of mesh-related pain are not well described whereas a meshectomy is controversial. Aims were to define mesh-related pain symptoms, to investigate long-term effects of a meshectomy and to provide recommendations on meshectomy.

METHODS

Consecutive patients undergoing open meshectomy with/without selective neurectomy for chronic inguinodynia following Lichtenstein repair were analysed including a follow-up questionnaire. Outcome measures were complications, satisfaction (excellent, good, moderate, poor) and hernia recurrence rate. Recommendations for meshectomy are proposed based on a literature review.

RESULTS

Seventy-four patients (67 males, median age 56 years) underwent mesh removal (exclusively mesh, 26%; combined with tailored neurectomy, 74%) between June 2006 and March 2015 in a single centre. Complications were intraoperatively recognized small bowel injury (n = 1) and testicular atrophy (n = 2). A 64% excellent/good long-term result was attained (median 18 months). Success rates of a meshectomy (63%) or combined with a neurectomy (64%) were similar. Five hernia recurrences occurred during follow-up (7%). A patient with a pure mesh-related groin pain characteristically reports a 'foreign body feeling'. Pain intensifies during hip flexion (car driving) and is attenuated following hip extension or supine position. Palpation is painful along the inguinal ligament whereas neuropathic characteristics (hyperpathic skin, trigger points) are lacking.

CONCLUSIONS

Mesh removal either or not combined with tailored neurectomy is beneficial in two of three patients with characteristics of mesh-related inguinodynia following Lichtenstein hernia repair who are refractory to alternative pain treatments.

Primary inguinal hernia: The open repair today pros and cons

Open anterior repair for inguinal hernia offers several distinct advantages over endoscopic repair, especially when real-world effectiveness is taken into account. The learning curve for endoscopic techniques is long, whereas the Lichtenstein and other open tension-free techniques are easier to teach and replicate at all levels. The outcomes of Lichtenstein repairs for primary inguinal hernia as performed by non-experts and supervised residents are comparable to those of experts. Moreover, open tension-free repair does not require expensive instruments or dedicated equipment, other than the prosthetic mesh. As such, it is feasible in any operating room anywhere in the world with limited costs. In our opinion, the most important advantage offered by open tension-free repair is that it can be performed under local anesthesia. Nevertheless, local anesthesia has some disadvantages: it requires training, excellent knowledge of the anatomy and the necessary technique, patience, and gentle handling of the tissues. Open inguinal hernia repair is a procedure that every surgeon should know and be able to perform because it is necessary to treat two conditions, groin hernia recurrence after a posterior approach (both laparoscopic and open) and pubic inguinal pain syndrome.

Efficacy of retroperitoneal triple neurectomy for refractory neuropathic inguinodynia

BACKGROUND

Refractory neuropathic inguinodynia following inguinal herniorrhaphy is a common and debilitating complication. This prospective study evaluated long-term outcomes associated with laparoscopic retroperitoneal triple neurectomy.

METHODS

Sixty-two consecutive patients (51 male; mean age, 47); all failing pain management; prior reoperation in 35, prior neurectomy in 26; average follow-up 681 days (range: 90 days to 3 years). Measured outcomes include numeric pain ratings, dermatomal mapping, histologic confirmation, quantitative sensory testing, complications, narcotic usage, and activity level.

RESULTS

Mean numerical pain scores were significantly decreased (baseline, 8.6) at all postoperative time points (POD 1, 3.6; P < .001: POD 90, 2.3, P < .001) with durable efficacy from POD 90 to 3 years (P < .001). Quantitative sensory testing showed marked group-level increases of sensory thresholds. Narcotic dependence decreased in 57/62 and was eliminated in 44/62 and activity level improved in 58/62.

CONCLUSIONS

Retroperitoneal triple neurectomy is an effective and durable treatment for refractory neuropathic inguinodynia.

Factors Determining Outcome After Surgery for Chronic Groin Pain Following a Lichtenstein Hernia Repair

BACKGROUND

Some patients develop chronic groin pain after a Lichtenstein hernia repair. Previous studies have demonstrated beneficial effects of removal of entrapped inguinal nerves or a meshectomy in patients with chronic pain after open inguinal hernia mesh repair. Factors determining success following this remedial surgery are unknown. The aim of the study was to identify potential patient- or surgery-related factors predicting the surgical efficacy for inguinodynia following Lichtenstein repair.

METHODS

Consecutive adult patients with a history of persistent pain following Lichtenstein repair who underwent remedial surgery were analysed using univariate analysis. Significant confounders (p < 0.05) were combined in a multivariate logistic regression model using a backward stepwise regression method.

RESULTS

A total of 136 groin pain operations were available for analysis. Factors contributing to success were removal of a meshoma (OR 4.66) or a neuroma (OR 5.60) and the use of spinal anaesthesia (OR 4.38). In contrast, female gender (OR 0.30) and preoperative opioid use (OR 0.38) were significantly associated with a less favourable outcome. Using a multivariate analysis model, surgery under spinal anaesthesia (OR 4.04), preoperative use of opioids (OR 0.37), and meshoma removal (OR 5.31) greatly determined surgical outcome.

CONCLUSIONS

Pain reduction after remedial surgery for chronic groin pain after Lichtenstein repair is more successful if surgery is performed under spinal anaesthesia compared to general anaesthesia. Removal of a meshoma must be considered as success rates are optimized following these measures. Patients using opioids preoperatively have less favourable outcomes.

Management of Postherniorrhaphy Chronic Neuropathic Groin Pain: A Role for Dorsal Root Ganglion Stimulation

Chronic neuropathic groin pain is a sequela of hernia surgery that occurs at unacceptably high rates, causing widespread impacts on quality of life. Although the medical community is beginning to recognize the role of surgical technique in the initiation and maintenance of postherniorrhaphy neuropathic pain, little information exists regarding pain management strategies for this condition. This review presents a summary of the pain condition state, its treatment options, and treatment recommendations. Both literature review and clinical experience were used to develop a proposed a treatment algorithm for the treatment of postherniorrhaphy pain. The development of chronic pain may be prevented via a number of perioperative measures. For pain that is already established, some surgical approaches including inguinal neurectomy can be effective, in addition to standard pharmacological treatments and local infiltrations. An unmet need may still exist with these options, however, leaving a role for neuromodulation for the treatment of intractable cases. A pain management algorithm for iterative interventions including stimulation of the dorsal root ganglion (DRG) is described. It is expected that cross-disciplinary awareness of surgeons for nonsurgical pain management options in the treatment of chronic neuropathic postherniorrhaphy pain will contribute to better clinical outcomes.

Risk factors for reoperation due to chronic groin postherniorrhaphy pain

BACKGROUND

Chronic groin postherniorrhaphy pain (CGPP) is common and sometimes so severe that surgical treatment is necessary. The aim of this study was to identify risk factors for being reoperated due to CGPP.

METHODS

All 195,707 repairs registered in the Swedish Hernia Register between 1999 and 2011 were included in the study. Out of these, 28,947 repairs were excluded since they were registered as procedures on the same patient after a previous repair. Age, gender, hernia anatomy (indirect reference), method of repair (anterior sutured repair reference) and postoperative complications were included in a multivariate Cox analysis with reoperation due to CGPP as endpoint.

RESULTS

Of the patients included in the study cohort, 218 (0.13%) later underwent reoperation due to CGPP, including 31 (14%) women. Median age at the primary repair was 61.5 years. Risk factors for being reoperated were age < median [hazard ratio (HR) 3.03, 95% confidence interval (CI) 2.22-4.12], female gender (HR 2.13, CI 1.41-3.21), direct hernia (HR 1.35, CI 1.003-1.81), other hernia (HR 6.03, CI 3.08-11.79), Lichtenstein repair (HR 2.22, CI 1.16-4.25), plug repair (HR 3.93, CI 1.96-7.89), other repair (HR 2.58, CI 1.08-6.19), bilateral repair (HR 2.58, CI 1.43-4.66) and postoperative complication (HR 4.40, CI 3.25-5.96).

CONCLUSIONS

Risk factors for being reoperated due to CGPP in this cohort included low age, female gender, a direct hernia, a previous Lichtenstein or plug repair, bilateral repair and postoperative complications. Further research on how to avoid CGPP and explore the effectiveness of surgery for CGPP is necessary.

Biologic mesh versus synthetic mesh in open inguinal hernia repair: system review and meta-analysis

BACKGROUND

Biologic meshes are mostly used for abdominal wall reinforcement in infected fields, but no consensus has been reached on its use for inguinal hernia repairing. The purpose of this study was to compare biologic mesh with synthetic mesh in open inguinal herniorrhaphy.

METHODS

A systematic literature review and meta-analysis was undertaken to identify studies comparing the outcomes of biologic mesh and synthetic mesh in open inguinal hernia repair. Published studies were identified by the databases PubMed, EMBASE and the Cochrane Library.

RESULTS

A total of 382 patients in five randomized controlled trials were reviewed (179 patients in biologic mesh group; 203 patients in synthetic mesh group). The two groups did not significantly differ in chronic groin pain (P = 0.06) or recurrence (P = 0.38). The incidence of seroma trended higher in biologic mesh group (P = 0.03). Operating time was significantly longer with biologic mesh (P = 0.03). There was no significant difference in hematomas (P = 0.23) between the two groups.

CONCLUSIONS

From the data of this study, biologic mesh had no superiority to synthetic mesh in open inguinal hernia repair with similar recurrence rates and incidence of chronic groin pain, but higher rate of seroma and longer operating time. However, this mesh still needs to be assessed in a large, multicentre, well-designed randomized controlled trial.

Retroperitoneal anatomy of the iliohypogastric, ilioinguinal, genitofemoral, and lateral femoral cutaneous nerve: consequences for prevention and treatment of chronic inguinodynia

PURPOSE

Chronic inguinodynia is one of the most frequent complications after groin herniorrhaphy. We investigated the retroperitoneal anatomy of the iliohypogastric, ilioinguinal, genitofemoral, and lateral femoral cutaneous nerve to prevent direct nerve injury during hernia repairs and to find the most advantageous approach for posterior triple neurectomy.

METHODS

We dissected the inguinal nerves in 30 human anatomic specimens bilaterally. The distances from each nerve and their entry points in the abdominal wall were measured in relation to the posterior superior iliac spine, anterior superior iliac spine, and the midpoint between the two iliac spines on the iliac crest. We evaluated our findings by creating high-resolution summation images.

RESULTS

The courses of the iliohypogastric and ilioinguinal nerve are most consistent on the anterior surface of the quadratus lumborum muscle. The genitofemoral nerve always runs on the psoas muscle. The entry points of the nerves in the abdominal wall are located as follows: the iliohypogastric nerve is above the iliac crest and lateral from the anterior superior iliac spine, the ilioinguinal nerve is with great variability, either above or below the iliac crest and lateral from the anterior superior iliac spine, the genital branch is around the internal inguinal ring, the femoral branch is either cranial or caudal to the iliopubic tract, and the lateral femoral cutaneous nerve is either medial or lateral to the anterior superior iliac spine.

CONCLUSION

Nerve injury during inguinal hernia repairs can be avoided by taking the topographic anatomy of the inguinal nerves into consideration. The most advantageous plane to look for the iliohypogastric and ilioinguinal nerve during posterior neurectomy is on the anterior surface of the quadratus lumborum muscle. For the surgical treatment of severe chronic inguinodynia, especially after posterior open or endoscopic mesh repair (TAPP/TEP), the retroperitoneoscopic or open retroperitoneal approach for posterior triple neurectomy can be considered.

[Diagnostics and therapy of chronic pain following hernia operation]

The frequency of chronic pain after hernia repair is currently much higher than the recurrence rate. For inguinal hernias it has been shown that mesh-based techniques are comparable to mesh-free techniques concerning chronic pain. Risk factors could be clearly identified for inguinal hernia repair and include open repair, meshes with small pores, mesh fixation with sutures or tacks, pre-existing pain and severe pain during the early postoperative period. The last two risk factors are also important for incisional hernias. For laparoscopic incisional hernia repair, the width (> 10 cm) of the gap seems to correlate with chronic pain. The diagnostic measures are restricted to the identification of a segmental problem in terms of nerve entrapment which can be blocked by local anesthesia or definite neurectomy. In some cases of chronic pain after inguinal hernia repair removal of the mesh will be advisable. After incisional hernia repair a segmental involvement is rarely seen. Localized pain may be induced by stay sutures which can be removed. Mesh removal is, however, a complex procedure especially after open repair resulting in hernia recurrence and therefore represents a salvage technique. The prophylaxis of chronic pain is therefore of utmost importance as is the identification of patients at risk which is now possible. These patients for example with inguinal hernias should be treated laparoscopically with an adequate technique including meshes with big pores and without fixation or fixation with glue only.

Surgical approach to abdominal wall defects: history and new trends

We briefly outline the history of hernia surgery development from the Ebers Papyrus to modern prosthetic repairs. The rapid evolution of anatomical, physiological and pathogenetic concepts has involved the rapid evolution of surgical treatments. From hernia sack cauterization to sack ligation, posterior wall repair (Bassini), and prosthetic reinforcement there has been an evident improvement in surgical treatment results that has stimulated surgeons to find new technical solutions over time. The introduction of prosthetic repair, the laparoscopic revolution, the impact of local anesthesia and the diffusion of day surgery have been the main advances of the last 50 years. Searching for new gold standards, the introduction of new devices has also led to new complications and problems. Research of the last 10 years has been directed to overcome prosthetic repair complications, introducing every year new meshes and materials. Lightweight meshes, composite meshes and biologic meshes are novelties of the last few years. We also take a look at future trends.

Self-gripping mesh versus sutured mesh in open inguinal hernia repair: system review and meta-analysis

BACKGROUND

The objective of this article was to compare the outcomes of self-gripping mesh (GM) with sutured mesh (SM) in open inguinal hernia repair.

METHODS

A systematic review and meta-analysis were taken to compare the outcomes of GM and SM in open inguinal hernia repair.

RESULTS

A total of 1,353 patients in 6 randomized controlled trials and 2 observational studies were reviewed (666 patients in GM group; 687 patients in SM group). The 2 groups did not significantly differ in chronic groin pain (P = .23) or recurrence (P = .59). The operating time was significantly shorter in GM group (P < .00001). There was no significant difference in infection (P = .18), seromas (P = .35), hematomas (P = .87), or discomfort (P = .58) between the 2 groups.

CONCLUSIONS

The data showed that GM was equivalent to SM in open inguinal hernia repair. However, this new mesh still needs to be confirmed in large, multi-center, well-designed randomized controlled trials.

Incidence of pain after inguinal hernia repair in the elderly. A retrospective historical cohort evaluation of 18-years' experience with a mesh & plug inguinal hernia repair method on about 3000 patients

Background

Chronic pain after prosthetic inguinal hernioplasty is one of the most important current issues in the current literature debate. Mechanisms related to pain development are only partially known. Influence of age as well as other factors is still unclear. The aim of this work was to evaluate whether development of chronic pain after open prosthetic plug and mesh inguinal hernioplasty is influenced by age.

Methods

Analysis was retrospectively conducted, dividing our cohort of patients (2,902) who had undergone prosthetic open plug&mesh inguinal hernioplasty from Jannuary 1994 to May 2012, following only the age criterion (cut-off 65 yrs.), into two groups (Gr.A<65 yrs, Gr.B>65 yrs.). All patients were routinely submitted to a postoperative questionnaire. Complications such as analgesic assumption were registered in both groups. Pain intensity was classified following the Visual Analogic Scale (VAS). Incidence of chronic pain, discomfort, and numbness, was assessed in both groups. Statistical significance was assessed by X₂-test.

Results

Only 0.2% of patients suffered from a recurrence in our cohort. Postoperative chronic pain was observed in Gr. A in 0.12% of patients vs Gr.B 0.09% (p>0.05). Incidence of other postoperative symptoms such as discomfort or numbness were slightly prevalent on young patients (respectively p = 0.0286 and p = 0.01), while for hyperesthesia and sensation of foreign body no statistically significant difference of incidence between groups was observed.

Conclusions

Real chronic pain after inguinal hernioplasty is a rare clinical entity. Other causes of chronic pain should be accurately researched and excluded. In young patients psychological factors seem to show a slight influence. There was no influence of age on chronic postoperative pain incidence after inguinal hernioplasty.