Histological findings in direct inguinal hernia: Investigating the histological changes of the herniated groin looking forward to ascertain the pathogenesis of hernia disease

A Rare Case of Penoscrotal Webbing and Extensive Hernias: An Anatomical Report With Genetic Insights

During a routine anatomical dissection of an 81-year-old male cadaver received through the Gift Body Program of Saint Louis University School of Medicine (SLU SOM), a massive bulging in the abdominal area was observed that was consistent with numerous hernia repairs noted in the donor's self-reported medical history. Gross anatomical dissection of the cadaveric body revealed extensive herniation of portions of the small intestine and peritoneal sac along the costal margin and extending to the left aspect of the abdomen. Additionally, an uncircumcised phallus was buried within the suprapubic fat pad and demonstrated simple, grade III penoscrotal webbing (PSW), creating an impression of micropenis presence. To gain additional insights into the current case, analysis of the coding regions (exomes) of DNA procured from the body for putative genetic variants was performed using next-generation sequencing (NGS) technology. This analysis revealed 110 rare (minor allele frequency (MAF) ≤ 0.01), pathologic/deleterious genetic mutations. The most relevant variants to this case were the ones associated with male sexual development, BMP1 and BMP4; connective tissue development, COL3A1 and COL5A3; cilia morphogenesis and function, DNAH5 and MAPK15; as well as hormonal homeostasis, ESR1. Direct involvement of BMP1 both in male sexual development and hernia genesis makes it a strong candidate for linking the two pathologies, PSW and multiple hernias, observed in the present case. Yet the presence of a group of mutated genes linked to myopathies (ITGA7, NRAP, POLM, SCN5A, XIRP2) and muscular dystrophy (ITGA7) raises a question about the involvement of these muscular pathologies in hernia genesis and unsuccessful hernia repairs associated with the current case.

Physiologic Cyclical Load on Inguinal Hernia Scaffold ProFlor Turns Biological Response into Tissue Regeneration

Surgical repair of groin protrusions is one of the most frequently performed procedures. Currently, open or laparoscopic repair of inguinal hernias with flat meshes deployed over the hernial defect is considered the gold standard. However, fixation of the implant, poor quality biologic response to meshes and defective management of the defect represent sources of continuous debates. To overcome these issues, a different treatment concept has recently been proposed. It is based on a 3D scaffold named ProFlor, a flower shaped multilamellar device compressible on all planes. This 3D device is introduced into the hernial opening and, thanks to its inherent centrifugal expansion, permanently obliterates the defect in fixation-free fashion. While being made of the same polypropylene material as conventional hernia implants, the 3D design of ProFlor confers a proprietary dynamic responsivity, which unlike the foreign body reaction of flat/static meshes, promotes a true regenerative response. A long series of scientific evidence confirms that, moving in compliance with the physiologic cyclical load of the groin, ProFlor attracts tissue growth factors inducing the development of newly formed muscular, vascular and nervous structures, thus re-establishing the inguinal barrier formerly wasted by hernia disease. The development up to complete maturation of these highly specialized tissue elements was followed thanks to biopsies excised from ProFlor from the short-term up to years post implantation. Immunohistochemistry made it possible to document the concurrence of specific growth factors in the regenerative phenomena. The results achieved with ProFlor likely demonstrate that modifying the two-dimensional design of hernia meshes into a 3D outline and arranging the device to respond to kinetic stresses turns a conventional regressive foreign body response into advanced probiotic tissue regeneration.

Dynamic Responsive Inguinal Scaffold Activates Myogenic Growth Factors Finalizing the Regeneration of the Herniated Groin

BACKGROUND

Postoperative chronic pain caused by fixation and/or fibrotic incorporation of hernia meshes are the main concerns in inguinal herniorrhaphy. As inguinal hernia is a degenerative disease, logically the treatment should aim at stopping degeneration and activating regeneration. Unfortunately, in conventional prosthetic herniorrhaphy no relationship exists between pathogenesis and treatment. To overcome these incongruences, a 3D dynamic responsive multilamellar scaffold has been developed for fixation-free inguinal hernia repair. Made of polypropylene like conventional flat meshes, the dynamic behavior of the scaffold allows for the regeneration of all typical inguinal components: connective tissue, vessels, nerves, and myocytes. This investigation aims to demonstrate that, moving in tune with the groin, the 3D scaffold attracts myogenic growth factors activating the development of mature myocytes and, thus, re-establishing the herniated inguinal barrier.

METHODS

Biopsy samples excised from the 3D scaffold at different postoperative stages were stained with H&E and Azan-Mallory; immunohistochemistry for NGF and NGFR p75 was performed to verify the degree of involvement of muscular growth factors in the neomyogenesis.

RESULTS

Histological evidence of progressive muscle development and immunohistochemical proof of NFG and NFGRp75 contribution in neomyogenesis within the 3D scaffold was documented and statistically validated.

CONCLUSION

The investigation appears to confirm that a 3D polypropylene scaffold designed to confer dynamic responsivity, unlike the fibrotic scar plate of static meshes, attracts myogenic growth factors turning the biological response into tissue regeneration. Newly developed muscles allow the scaffold to restore the integrity of the inguinal barrier.

Fixation free laparoscopic obliteration of inguinal hernia defects with the 3D dynamic responsive scaffold ProFlor

Laparoscopic TAPP/TEP approaches are well-established options for the cure of inguinal hernias. As in the open approach, mesh fixation and poor-quality biologic response represent controversial questions and are a source of concerns. Furthermore, hernia defect patency represents another problem which seems not well acknowledged among surgeons. These problems are considered the cause of frequent intra and postoperative complications. To overcome these concerns, recently a different concept of cure has emerged. Based on a newly developed dynamic responsive 3D scaffold named ProFlor, a permanent hernia defect obliteration has been finalized. Following its inherent centrifugal expansion due to its dynamic responsivity, this hernia device is positioned fixation free within the defect and induces a probiotic biological response allowing for the re-establishment of the degenerated inguinal barrier. A laparoscopic approach with the 3D scaffold has been tested on 71 patients to demonstrate its effectiveness in reducing intra and postoperative complications. The operated patients presented with bilateral and/or recurrent inguinal hernia. Overall, 122 hernia defects were obliterated with 119 dynamic responsive scaffolds. The procedures were carried out from January 2018 to January 2022 with a defined protocol and detailed procedural steps. The laparoscopic technique with the 3D hernia scaffold allowed for fixation free placement, permanent defect obliteration and dynamically induced regenerative effects. The technique proved effective in reducing intra and postoperative complications. In particular, early postoperative pain and discomfort significantly decreased. No chronic pain and no recurrences were reported during follow up. The results achieved with the described laparoscopic technique seem to embody an innovative concept for inguinal hernia repair. Fixation free, dynamic responsive, permanent defect obliteration, histologically proven regenerative effects are the distinctive features of this 3D scaffold. It seems to embody a more physiological and pathogenetically coherent concept of cure, thus improving treatment results of this widespread disease.

A regenerative 3D scaffold for inguinal hernia repair. MR imaging and histological cross evidence. Qualitative study

BACKGROUND

Inguinal hernia is a degenerative disease occurring in a high motile surround. Stopping degeneration and promoting tissue regeneration should be the treatment goal. Groin hernias are conventionally managed with static flat meshes, mostly fixated to the delicate inguinal environment. Far from a regenerative effect, the biologic response of conventional hernia meshes is characterized by a foreign body reaction leading to a stiff/shrunken scar plate, which is often the source of unpleasant complications. Recently, a newly engineered 3D device for inguinal hernia repair - ProFlor-has been developed to produce a regenerative biological response. Unlike conventional hernia meshes, this regenerative 3D hernia scaffold seems to demonstrate suitable features for a pathogenetical and physiological coherent treatment of the disease. The aim of this manuscript is to cross evidence these features through magnetic resonance imaging (MRI) and histology.

STUDY DESIGN

The biological response of ProFlor at three defined post-implantation stages has been evaluated through MRI signal intensity and compared to neighbouring muscles and fat. As additional proof, histology of tissue specimens excised at the same post-implantation periods from porcine models during an experimental attempt were also evaluated.

RESULTS

MRI of newly ingrown tissue in ProFlor demonstrated similar signal intensity of muscles while fat tissue showed remarkably higher values. These data matched with the histology of ProFlor biopsies excised from pigs.

CONCLUSIONS

The motile compliance to groin movements of ProFlor appears to induce a probiotic biologic response comparable to a regenerative scaffold, allowing to physiologically resolve the degenerative source of inguinal hernia disease.

Inguinal Hernia: Defect Obliteration with the 3D Dynamic Regenerative Scaffold Proflor™

Prosthetic inguinal hernia repair presents significant challenges. Some of these, such as mesh fixation and quality of the biologic response, are still debated among surgeons. For example, there is no strong consensus regarding a specific condition that characterizes the surgical procedure during herniorrhaphy. This issue concerns management of the hernia defect, which in conventional hernia repair with flat meshes remains patent. However, a critical analysis of typical postoperative complications after inguinal hernia repair reveals that some of these adverse events are related to patency of the hernial opening. Postoperative discomfort, pain with specific movements and even hernia recurrence can be caused by incomplete or defective management of the hernia defect. For this reason, a deeper understanding of this topic would be useful for improving postoperative outcomes. A recently updated concept for inguinal hernia repair takes this technical aspect into consideration. It is based on the use of a newly developed 3D scaffold-ProFlor™ (Insightra Medical, Inc., Clarksville, TN, USA)-that is intended to be deployed into the defect. This novel hernia repair device has interesting and original features, such as dynamic responsivity in compliance with inguinal movement, fixation-free mode and regenerative behavior that counteracts the degenerative effects of the disease. Another additional proprietary feature of this 3D scaffold is the full and permanent obliteration of the defect, which is a crucial aspect to improve outcomes by avoiding the typical adverse effects of this surgical procedure. Obliteration of the hernia defect with the 3D dynamic regenerative scaffold ProFlor™ appears to be superior to coverage by means of static (passive) flat meshes/plugs used in conventional hernia repair. This report highlights the principles of this procedural approach.

Enhanced angiogenesis in the 3D dynamic responsive implant for inguinal hernia repair ProFlor

Biologic response to hernia prostheses represents a continuous source of debate. Conventional hernia meshes, in their typical static, passive configuration have been used for decades to reinforce the herniated abdominal wall. These flat implants, mainly fixated with sutures or tacks, induce poor quality fibrotic ingrowth that shrinks the mesh. In groin hernia repair, flat meshes are applied in the delicate inguinal surrounding where uncontrolled development of a scar plate can impair movement and may incorporate the sensitive nerves crossing this area. Complications deriving from mesh fixation and nerve entrapment are frequent and unpleasant for patients. To remedy these problems, a multilamellar shaped 3D device with a dynamic responsive behavior has recently been developed to repair inguinal hernia. Its inherent dynamic compliance during inguinal movements has shown to induce enhanced biological response with ingrowth of newly formed connective tissue, muscle fibers, and nerves. The function of these highly specialized tissue structures is supported by the contextual development of newly formed arteries and veins. The scope of the study was to assess quantity and quality of vessels, which had ingrown in the 3D hernia device in the short-term, medium-term, and long-term post-implantation, in biopsy specimens gathered from inguinal hernia patients operated with the 3D device. Starting from an early stage, widespread angiogenesis was evident within the 3D structure. Arteries and veins increased in quantity showing progressive development until full maturation of all specific vascular components throughout the mid-term, to long-term, post-implantation. High quality biologic ingrowth in hernia prosthetics needs an adequate vascular support. The broad network of mature arteries and veins evidenced herewith seems to confirm the enhanced biological features of the dynamic responsive 3D device whose features resemble a regenerative scaffold, an ideal feature for the treatment of the degenerative source of inguinal hernia disease.

High-resolution ultrasound of spigelian and groin hernias: a closer look at fascial architecture and aponeurotic passageways

From the clinical point of view, a proper diagnosis of spigelian, inguinal and femoral hernias may be relevant for orienting the patient's management, as these conditions carry a different risk of complications and require specific approaches and treatments. Imaging may play a significant role in the diagnostic work-up of patients with suspected abdominal hernias, as the identification and categorization of these conditions is often unfeasible on clinical ground. Ultrasound imaging is particularly suited for this purpose, owing to its dynamic capabilities, high accuracy, low cost and wide availability. The main limitation of this technique consists of its intrinsic operator dependency, which tends to be higher in difficult-to-scan areas such as the groin because of its intrinsic anatomic complexity. An in-depth knowledge of the anatomy of the lower abdominal wall is, therefore, an essential prerequisite to perform a targeted ultrasound examination and discriminate among different types of regional hernias. The aim of this review is to provide a detailed analysis of the fascial architecture and aponeurotic passageways of the abdominal wall through which spigelian, inguinal and femoral hernias extrude, by means of schematic drawings, ultrasound images and video clips. A reasoned landmark-based ultrasound scanning technique is described to allow a prompt and reliable identification of these pathologic conditions.

First-in-man permanent laparoscopic fixation free obliteration of inguinal hernia defect with the 3D dynamic responsive implant ProFlor-E®. Case report

INTRODUCTION

In the case of inguinal hernia recurrence after primary anterior repair, international guidelines strongly suggest a posterior laparoscopic approach. The 3D dynamic-responsive prosthesis for inguinal hernia repair ProFlor-E® has recently been introduced to the market. The present report describes the results of the first-in-man laparoscopic inguinal hernia repair carried out with ProFlor-E®.

PRESENTATION OF CASE

A 71-year-old male Caucasian presented with recurrent inguinal hernia after primary anterior repair. A fixation free TAPP procedure with ProFlor-E® was planned. Implant delivery and placement to obliterate the defect was quick and safe. Postoperatively, starting from 2nd postop day, pain was practically absent allowing quick return to normal activities. During follow up, US and MRI scans confirmed the permanence of ProFlor-E® in the hernial gap. During 16-month follow-up no complications were reported.

DISCUSSION

Flat meshes used to reinforce the herniated inguinal area is a well-established concept. Notwithstanding, such static and passive implants leave the defect patent and cause specific complications related to mesh fixation and uncontrolled poor quality fibrotic ingrowth. ProFlor-E® respects the inguinal physiology resolving these issues. Its centrifugal expansion and dynamic responsivity allows for fixation-free defect obliteration, thus avoiding complications, above all tissue tear, bleeding, mesh invagination, discomfort and chronic pain. In accord with the degenerative pathogenesis of hernia disease, by acting as a regenerative scaffold, ProFlor-E® restores the inguinal barrier promoting the regeneration of the typical inguinal components.

CONCLUSION

This initial experience seems to prove that ProFlor-E® can also be used with the laparoscopic approach achieving excellent results.

Inguinal Ring RNA Sequencing Reveals Downregulation of Muscular Genes Related to Scrotal Hernia in Pigs

Scrotal hernias (SH) are common congenital defects in commercial pigs, characterized by the presence of abdominal contents in the scrotal sac, leading to considerable production and animal welfare losses. Since the etiology of SH remains obscure, we aimed to identify the biological and genetic mechanisms involved in its occurrence through the whole transcriptome analysis of SH affected and unaffected pigs’ inguinal rings. From the 22,452 genes annotated in the pig reference genome, 13,498 were expressed in the inguinal canal tissue. Of those, 703 genes were differentially expressed (DE, FDR < 0.05) between the two groups analyzed being, respectively, 209 genes upregulated and 494 downregulated in the SH-affected group. Thirty-seven significantly overrepresented GO terms related to SH were enriched, and the most relevant biological processes were muscular system, cell differentiation, sarcome reorganization, and myofibril assembly. The calcium signaling, hypertrophic cardiomyopathy, dilated cardiomyopathy, and cardiac muscle contraction were the major pathways possibly involved in the occurrence of the scrotal hernias. The expression profile of the DE genes was associated with the reduction of smooth muscle differentiation, followed by low calcium content in the cell, which could lead to a decreased apoptosis ratio and diminished muscle contraction of the inguinal canal region. We have demonstrated that genes involved with musculature are closely linked to the physiological imbalance predisposing to scrotal hernia. According to our study, the genes MYBPC1, BOK, SLC25A4, SLC8A3, DES, TPM2, MAP1CL3C, and FGF1 were considered strong candidates for future evaluation.

Deep SSI after mesh-mediated groin hernia repair: management and outcome in an Emergency Surgery Department

AIM

Mesh-mediated groin hernia repair is considered the goldstandard procedure. It has low recurrence rate. Rarely a deep Surgical Site Infection (SSI) is seen when a synthetic prosthesis is used.

CASE REPORT

We describe a rare case of bilateral deep SSI after mesh-mediated groin hernia repair. Diagnosis was performed through the physical examination and radiological exams. Microbiological samples identified a methicillin-resistant Staphylococcus aureus responsible of the infection. Target therapy was performed and re-operation performed in order to remove the infected prosthesis and to apply a biological one to create the fibrous scaffold. During follow-up time, right side recurrence was observed. Tru-cut biopsy of fascia was obtained in order to identify the responsible of the recurrence.

CONCLUSION

Combination of antibiotic therapy and surgical reoperation seems to be the correct way to approach the deep SSI after mesh-mediated groin hernia repair. The use of biological mesh after synthetic removal seems to improve the final outcome.

[Sportsmen's groin : Definition, differential diagnosis and treatment]

Groin pain in athletes is a common problem and can have extensive consequences for professional athletes. The anatomical and functional complexity of the groin as well as radiating pain from remote anatomical regions can make the differential diagnosis a challenge and requires special attention. As there are a wide variety of possible causes for groin pain, a multidisciplinary approach is required. The treating orthopedic surgeon needs to pay special attention to pre-arthritic hip deformities to avoid irreversible damage of the hip joint. By a meticulous patient history and identification of the pain character, followed by clinical, sonographic and radiographic investigations, a differential diagnosis can usually be achieved. Besides typical orthopedic causes, pathological findings particularly in the area of the groin need to be considered, clarified and adequately treated; therefore, a clear terminology of the different diseases is necessary. Sportsmen's groin is not a hernia but should be perceived as a separate entity due to its typical pain character and detection of a measurable protrusion of the posterior wall of the inguinal canal by ultrasound.

The Septum Inguinalis: A Clue to Hernia Genesis?

Purpose: Double ipsilateral inguinal ("pantaloon") hernias and also the more advanced "combined" inguinal hernia involve disruption of the inguinal floor. In the case of pantaloon hernias, the medial boundary of the internal ring remains intact but in combined hernias this is fully disrupted, producing a single hernial protrusion. Deepening the pathophysiology of these hernias may be helpful in addressing hernia genesis, thus improving strategies for the treatment of this disease. Materials and Methods: A cohort of 22 patients who underwent inguinal hernia repair showed double ipsilateral (pantaloon) hernia, comprising distinct direct and indirect protrusions separated by a tissue septum. In 19 patients, the septal arrangement dividing the 2 hernias showed macroscopically evident structural damages, then excised and histologically studied. Different tissue markers were used for the identification of the structural damages. Results: Macroscopically, the divisor septum represents the boundary between internal ring and Hesselbach's triangle. Anteriorly it is composed by fibers of the internal oblique and transverse muscles, which form a complex with the inferior epigastric vessels on the corresponding posterior side of the inguinal floor. In the patient cohort studied, this anatomical structure showed a progressive sufferance characterized by chronic compressive damage. Conclusion: The anatomical structure which separates the indirect and direct components of a pantaloon hernia, herein referred to as the "septum inguinalis", has been shown progressively alter in both macro- and microscopically until it f undergoes disruption with development of a combined hernia. Understanding of this anatomical concept may help surgeons to perform sound repairs of these complex hernias.

Shift from androgen to estrogen action causes abdominal muscle fibrosis, atrophy, and inguinal hernia in a transgenic male mouse model

Inguinal hernia is one of the most common disorders that affect elderly men. A major pathology underlying inguinal hernia is the fibrosis and other degenerative changes that affect the lower abdominal muscle strength adjacent to the inguinal canal. Here we describe a critical role of estrogen and its nuclear receptor that enhance fibroblast proliferation and muscle atrophy, leading to inguinal hernia. Further research may reveal a potential role of estrogen ablation to prevent muscle fibrosis or hernia in a subset of elderly men.

Inguinal hernia develops primarily in elderly men, and more than one in four men will undergo inguinal hernia repair during their lifetime. However, the underlying mechanisms behind hernia formation remain unknown. It is known that testosterone and estradiol can regulate skeletal muscle mass. We herein demonstrate that the conversion of testosterone to estradiol by the aromatase enzyme in lower abdominal muscle (LAM) tissue causes intense fibrosis, leading to muscle atrophy and inguinal hernia; an aromatase inhibitor entirely prevents this phenotype. LAM tissue is uniquely sensitive to estradiol because it expresses very high levels of estrogen receptor-α. Estradiol acts via estrogen receptor-α in LAM fibroblasts to activate pathways for proliferation and fibrosis that replaces atrophied myocytes, resulting in hernia formation. This is accompanied by decreased serum testosterone and decreased expression of the androgen receptor target genes in LAM tissue. These findings provide a mechanism for LAM tissue fibrosis and atrophy and suggest potential roles of future nonsurgical and preventive approaches in a subset of elderly men with a predisposition for hernia development.

Mannheim Peritonitis Index (MPI) and elderly population: prognostic evaluation in acute secondary peritonitis

INTRODUCTION

Acute Secondary Peritonitis due to abdominal visceral perforation is characterized by high mortality and morbidity risk. Risk stratification allows prognosis prediction to adopt the best surgical treatment and clinical care support therapy. In Western countries elderly people represent a significant percentage of population Aim. Evaluation of Mannheim Peritonitis Index (MPI) and consideration upon old people.

PATIENTS AND METHODS

Retrospective study on 104 patients admitted and operated for "Acute Secondary Peritonitis due to visceral perforation". MPI was scored. In our study we want to demonstrate efficacy of MPI and the possibility to consider older age an independent prognostic factor.

RESULTS

Mortality was 25.96%. Greatest sensitivity and specificity for the MPI score as a predictor of mortality was at the score of 20. MPI score of <16 had 0.15 times lower risk of mortality compared to patients with MPI score 17 - 21 and 0.61 lower than patients with MPI >22. Patients with MPI score 17-21 had 0.46 times lower risk of mortality compared to patients with MPI score >21. In the group of patients with MPI score of >20 the mortality rate was 48.5% for patients older than 80 years old and 12.1% for younger patients (p < 0.005); in the group with MPI score of < 20 mortality rate was respectively 8.4% and 1.4% (p < 0.005).

DISCUSSION AND CONCLUSIONS

Data confirm the accuracy of the test. MPI score and age over 80 years old resulted independent predictors of mortality at multivariate analysis.

[Sportsmen's groin. Definition, differential diagnostics and therapy]

Groin pain in athletes is a common problem and can have extensive consequences for professional athletes. The anatomical and functional complexity of the groin as well as radiating pain from remote anatomical regions can make the differential diagnostic a challenge and requires special attention. As there are a wide variety of possible causes for groin pain, a multidisciplinary approach is required. The treating orthopedic surgeon needs to pay special attention to prearthritic hip deformities to avoid irreversible damage of the hip joint. By a meticulous patient history and identification of the pain character, followed by clinical, sonographic and radiographic investigations, a differential diagnosis can usually be achieved. Besides typical orthopedic causes pathological findings particularly in the area of the groin need to be considered, clarified and adequately treated; therefore, a clear terminology of the different diseases is necessary. Sportsmen's groin is not a hernia but should be perceived as a separate entity due to its typical pain character and detection of a measurable protrusion of the posterior wall of the inguinal canal by ultrasound.