Inguinal Hernia in Children: A Literature Review

2.1 Embriology

According to Ramachandran et al. [4] the processus vaginalis is described as a tongue of the peritoneal membrane present in both males and females, which establishes and perforates the muscle layer of the abdominal wall. In males, the testis precedes the Processus vaginalis’s descent through the tunnel. Initially, the gonad is located near the diaphragm, where it is attached to the craniosuspensory ligament. However, as the abdominal cavity extends and the developing intestines return to the coelomic cavity, the testis drops between 8 and 15 weeks after fertilization. The second stage occurs in males in whom the inguinal canal is a restored passage. The gubernaculum connects to the lower pole of the testis and the processus vaginalis, facilitating the movement of both structures via the inguinal canal.

Literature and evidence have shown that the testes remain undescended until the scrotum has fully formed, often occurring between 25 and 35 weeks of gestation. Some authors claim that a calcitonin gene-related peptide plays a role in this process. After that, the last relevant step is the closure of the processus vaginalis. It has also been shown that the thickening of the peritoneal membrane has been linked to smooth muscle differentiation at the neck of the hernial sac, where it has been suggested that the hepatocyte growth factor is involved. However, embryologic changes seem to be an important factor in the predisposition to developing hernias. As proof of this, evidence shows that the premature closure of the processus vaginalis on the left side, compared to the right side, increases the likelihood of right-sided inguinal hernias [4].

2.2 Epidemiology

Inguinal hernias represent a prevalent concern in pediatric surgery. It is undeniable that this condition is becoming more frequent in the field [4, 5]. According to Khan et al. [6], its incidence is approximately 8 to 50 per 1000 live births in term newborns, reaching nearly 20% in extremely low-birth-weight (<1000 g) neonates. Glick et al. [7] reported evidence that shows differences in the appearance of hernias between males and females, as the reported ratios are around 3:1 and 10:1. Approximately 60% of hernias are right-sided. This is true for both males and females. In males, this is possibly the result of a later descent of the right testicle than the left, but this does not explain the observation in females. The presentation of bilateral hernias occurs approximately 10% of the time. In accordance with multiple authors, patients with left-sided hernias are more likely to develop a right-sided hernia than vice versa [7]. Other differences are related to hernia content. While in boys, the most commonly herniated intra-abdominal content is the small intestines, in female infants, it is the ovaries; nevertheless, after 1 year of age, the bowel becomes more common in both sexes, and a herniated ovary in an adolescent is a rare finding [8].

According to Yeap et al. [5], around 99% of inguinal hernias in children are indirect. It seems to be that direct hernias are more frequent findings in adults. However, they can also be present in children as a bulging in the Hesselbach’s triangle. Furthermore, several authors have found a correlation between the incidence of inguinal and gestational age. It seems to be an indirect proportion, as age decreases, the incidence of inguinal hernias increases. The risk of developing an inguinal hernia in a male infant born at 24 weeks of gestation is 40%. In contrast, the incidence of male infants born after 32 weeks of gestation falls to 4% [4].

The incidence of inguinal hernias is indirectly proportional to birthweight, as it gradually decreases as birthweight increases. Neonates with a birthweight under 1000 g had an incidence of inguinal hernia between 30% and 42%. In contrast, neonates with a birthweight of around 1500 g had a lower incidence of inguinal hernia, being just about 3% [4].

The same association has been found between inguinal hernia occurrence and birthweight. Neonates with a birthweight under 1000 g presented 30 and 42% frequency of inguinal hernia. In contrast, neonates with a birthweight of around 1500 g had a lower incidence of inguinal hernia, being just about 3% [4].

2.3 Associations and risk factors

Inguinal hernias have many associated conditions (Table 1). The most common association is prematurity due to interruption of the normal process of testicular descent as well as comorbidities (e.g., chronic lung disease) in this population [9].

Cystic fibrosis (CF) carries an increased incidence of 15% of inguinal hernia. Interestingly, it has been shown a higher incidence of inguinal hernia in children whose parents or siblings never had one. This may be because of genetic factors as well as the physical effects of chronic lung disease and high intra-abdominal pressure. Cystic fibrosis is also a risk factor for bilaterality and recurrence [9].

A small or absent vas is occasionally found during inguinal hernia repair in males. Renal ultrasound should be electively obtained to evaluate for associated ipsilateral renal agenesis. Congenital absence of the vas is a heterogeneous disorder, largely due to mutations in the cystic fibrosis gene. Holcomb et al. [9] observed varying genotypes, with congenital absence of the vas as an isolated entity versus congenital absence of the vas along with renal anomalies. Moreover, there is a correlation between 15 and 25% of ventriculoperitoneal shunts (VPSs) used for hydrocephalus treatment with a greater occurrence of inguinal hernia, as well as increased rates of bilaterality, incarceration, and recurrence [8, 10, 11]. This is also more common in neonates and boys than in older infants and girls. It is also important to highlight that the average time between the insertion of a VPS and the surgical correction of an inguinal hernia is between 5 and 12 months. Peritoneal dialysis, ascites, and hydrops have similar associations with the present inguinal hernia [11].

2.4 Classification

As we have discussed, hernias can be classified into two major categories: direct and indirect [3]. The formation of the inguinal canal is related to the descent of the testis during fetal development or the formation of the labia in females, which is why indirect hernias are more prevalent in children and are often linked with the persistence of processus vaginalis. What characterizes this type of hernia is that the content moves laterally to the inferior epigastric vessels to access the deep inguinal ring [3, 5, 12, 13, 14, 15]. On the other hand, direct hernias are more often observed in adults, related to a weakness in the Hesselbach triangle. Nevertheless, they can sometimes be observed in teenagers as well; frequently, they are acquired in surgery. As an example, there are cases of recurrent inguinal hernia after ligation of a congenital defect during primary repair or metachronous contralateral inguinal hernia after identifying the closed open process vaginalis in males or the open canal of Nuck in females. Therefore, the acquired form of inguinal hernia can also manifest as an indirect hernia. Unilateral and bilateral hernias can be observed as well [3, 16].

Additionally, it is crucial to determine whether the patient’s inguinal hernia is reducible or not, which leads us to define the term strangulation. This denotes the state in which the hernia cannot be effectively reduced with manipulation. It is crucial to ascertain whether the patient requires urgent surgical surgery, since this particular hernia might include the colon, omentum, or the ovary/fallopian tube in females. Incarcerated hernia carries the risk of strangulation, which is the condition when the hernia’s contents have compromised blood flow. That is why this is a clinical emergency that requires immediate surgery. It may cause a blockage in the intestines, reduced blood flow, tissue death, perforation, or testicular atrophy in boys and ovarian injury in girls [3].

According to Kawalec et al. [3], there is a preoperative classification that has been modified from the original Nyhus classification for pediatric patients. Based on this, the first type, pediatric Nyhus type 0 (PN0), is characterized by a persistent process vaginalis without any hernia symptons. Pediatric Nyhus type I (PNI) is a clinical scenario in which the hernia is not detected during the examination and is diagnosed through a reliable history and silk glove sign or during laparoscopy. In the same vein as the PN0, there is no clinical hernia. Pediatric Nyhus type II (PNII) is identified when the hernia takes time to manifest after repeated straining for more than 30 seconds and manipulations are required, and it also encompasses irreducible hernias. In pediatric Nyhus type III (PNIII), hernias manifest promptly upon minor straining or spontaneously and are easily resolved with minimal manipulation [17].

Additionally, other types of hernia can be found, such as pantaloon hernia that is an indirect hernia that may cause dilatation of the deep ring, causing the weakening of the posterior wall, which may cause bulging of the hernia sac on both sides of the inferior epigastric vessels. [18] Amyand’s hernia is when the appendix is trapped within an inguinal hernia, which is only about 1% of all hernias. [19] Littré’s hernia is a clinical entity defined by the presence of Meckel’s diverticulum within a hernia sac [20].

2.5 Clinical findings

Parents typically discover inguinal hernias during bath time; if not, usually the pediatrician discovers them during a physical exam (Figure 1). When taking the history of the present illness, it is important to separate inguinal hernias from communicating hydroceles, undescended testis, and inguinal adenopathy. However, although hernias may manifest right after birth or after days, weeks, months, or even years later, the abnormality usually has been there since birth. This point becomes important to remember when asymptomatic hernias are found, in terms of the timing of surgery and the activities children should be allowed to participate in while awaiting repair.

Usually, hernias are asymptomatic. However, they are frequently mistakenly identified by parents as the cause of the distress symptoms of infants because they commonly appear in conjunction. In fact, in accordance with Glick et al., many of these symptoms, such as inguinal or groin pain during exercise, persist after the surgery [7].

In the same vein, incarceration is one of the primary complications of inguinal hernias in early infancy, which is why they are regarded as high-risk hernias, occasionally leading to intestinal obstruction and strangulation (Figure 2) [21, 22]. Evidence shows that younger gestational age increases the risk of incarceration and is up to 39% in premature and 3–16% in term infants. Other factors with increased risk of incarceration are age less than 1 year and female sex [23]. Although we have already mentioned that this type of hernia is the result of the entrapment of the intestines or other organs, the real question is whether entrapment occurs at the internal or external ring. According to Glick et al. [7], it can occur at both levels, but mainly at the level of the internal ring, leading to intermittent pain and irritability and signs of bowel obstruction (distension, vomiting, and obstipation). They found that in a not-reduced hernia, blood supply to the incarcerated organ may be compromised to the point of infarction (strangulated inguinal hernia) (Figure 3). Glick et al. [7] reported that patients may show peritonitis. This process can occur in as little as 2 hours. Incarceration occurs most commonly in the first 6 months of life, and after age 5, it is a rare finding.

In accordance with Fraser et al. [11], peritonitis, hemodynamic instability, and septic shock are considered absolute contraindications to attempt reduction, while symptoms of bowel obstruction are considered relatives. According to Fraser et al. [11], “a sudden ‘pop’ of the contents back into the peritoneal cavity usually confirms a successful reduction. Reduction in mass, in which the hernia contents are reduced into the peritoneal cavity but the bowel remains incarcerated internally in the hernia sac, is a very rare occurrence, but the surgeon should be aware of this possibility” [11].

2.6 Diagnosis

The diagnosis is often made through a physical exam and the history of a bulge in the groin accompanied by weeping. In the event that a child is incapable of coughing on command, alternative methods may be implemented to elevate intra-abdominal pressure. Holding the legs and limbs of infants against the examination table in a gentle manner to prevent them from moving always results in crying. For older children, other strategies might be employed, such as blowing bubbles or tickling them to induce laughter. In some cases, despite using this and other methods, the bulge does not show up. In cases where this happens, the silk purse or silk glove sign has been proposed as an alternative to observing the protrusion. The sensation of the sac moving on its own during this maneuver is a positive discovery. The silk purse sign was used with a wide range of diagnostic accuracy in reports published from 1950 to 1970. However, a recent prospective study conducted in China demonstrated that this physical finding had a sensitivity of 91% and a specificity of 97.3% in the diagnosis of inguinal hernias. In other words, this sign should not be considered conclusive to establish a hernia diagnosis [24].

2.7 Radiologic investigations

Ultrasonography, computed tomography, and magnetic resonance imaging are among the several radiologic modalities that are employed for diagnosis. Evidence has shown that ultrasound is the least invasive one, although it is important to take into account that its effectiveness is significantly contingent upon the abilities of the health professional. In addition, it can detect an inguinal hernia with a sensitivity of 86% and a specificity of 77% [24]. Thickening of the spermatic cord generally helps diagnose inguinal hernias in children [25]. However, in cases where the diagnosis is uncertain, computed tomography (CT) imaging is advantageous. It has a sensitivity of 80% and a specificity of 65% for the detection of complex inguinal hernias. On the other hand, despite its high percentage of sensitivity (95%) and specificity (96%) in the detection of inguinal hernias, magnetic resonance is infrequently used due to its cost. Nevertheless, it can be used to assist in the differentiation of sports-related injuries versus inguinal hernias [24].

2.8 Differential diagnosis

An increase in the volume of the groin or scrotum can be caused by other diseases, which is why it may be confused with an inguinal hernia (Table 2) [26, 27]. A few examples may be hydrocele, which can be associated with concomitant viral disease, elevating intraabdominal pressure due to sneezing, and increased fluids. Other examples are inguinal lymphadenopathy and idiopathic scrotal edema, which can be recognized by a subacute redness and swelling that is typically not excruciating. An abscess may also be confused with an incarcerated inguinal hernia, but it is important to observe the presence of purulent fluid [5]. An inguinal hernia or a hydrocele of the cord can also be confused with ectopic testicles with interstitial, preperitoneal, pre-pubic, and inguinocrural. As in all undescended testicles, the gonad will be missing in the scrotum, which will make the diagnosis. Ultrasound is useful as well. In the case of a torsion of an undescended testicle located in the inguinal region, the history of having an empty scrotum since birth and continuous pain in the region can suggest the diagnosis [27]. Uncommon conditions that should be considered include varicoceles, which may be identified by a palpable feeling of a bag of worms upon inspection. A healthcare provider would easily be able to detect and diagnose a testicular tumor, making it impossible to reduce in size [5].

2.9 Time of repair

The surgery is typically conducted promptly following the diagnosis. Sedation and manual reduction are successful in over 80% of cases when attempting to reduce an incarcerated hernia. Typically, an elective operation is performed within 24 hours of the reduction. Re-incarceration is inevitable when surgery is postponed [21, 28]. It is unnecessary to restrict the activities of an asymptomatic infant prior to surgery. Prompt repair may reduce incarcerated hernias in infants [11].

A study conducted in Canada discovered that the risk of incarceration for children under the age of one was doubled when the repair was performed more than 2 weeks after the diagnosis [29].

Inguinal hernias are common in the neonatal intensive care unit, but the timing of repair is widely variable among surgeons and between institutions and is controversial in premature infants. Repair of an inguinal hernia shortly prior to neonatal discharge can be more technically demanding, has higher recurrence and complication rates, may prolong mechanical ventilation and length of stay in the neonatal intensive care unit, and is associated with an increased risk of apnea and bradycardia [30, 31].

Late inguinal hernia repair (after 55-week postconceptual age) carries an increased risk of incarceration (10–30%), more frequent emergency department and clinic visits and readmissions, and potential failure of the family to follow-up [30]. Concerns about the long-term neurodevelopmental risks of anesthesia in premature infants, if substantiated, would favor the late approach. In a recent database survey, approximately 40% of premature infants underwent early repair, but the variability between hospitals was significant [32].

2.10 Management

Inguinal hernia surgery is one of the most frequently performed procedures in childhood, with an average operation rate of 5% that can increase to 30% in preterm infants [33, 34]. Surgical closure is always necessary because inguinal hernias do not resolve spontaneously [7, 34]. The American Academy of Pediatrics Surgical Section in 2005 emphasized that the majority of surgeons prefer to perform the operation either before discharge from the neonatal intensive care unit or as early as possible due to the high risk of inguinal hernia incarceration before the age of 6 months and within the first 2 weeks of diagnosis. The exploration of the contralateral groin in the event of unilateral hernia remains a subject of debate. In male infants, most surgeons explore and repair only the clinically evident side, but practice varies for female infants: Some prefer the routine exploration of the contralateral side, others do so only in selected populations, and others do not explore at all or avoid contralateral exploration unless indicated by laparoscopic examination [33].

Routine use of prophylactic antibiotics is not recommended for laparoscopic or elective open repair in low-risk patients. Antibiotic prophylaxis should be considered if risk factors for infection are present. Risk factors include recurrent hernias, immunosuppressed patients, obesity, diabetes, contamination, and urinary catheters [35].

A combination of local anesthesia and peripherally acting agents (paracetamol, non-steroidal antiinflammatory drugs, or a combination) is best treated for postoperative pain. Local infiltration of the wound or regional nerve blocks provide extra pain control and limit the use of analgesics [35].

2.11 Nonoperative management

In the absence of apparent indicators of shock or peritonitis in patients, nonoperative management is initially implemented. If feasible, elevate the child’s feet and attempt to soothe them without feeding them [36]. Furthermore, it is necessary to place the left index and middle fingers on the ipsilateral anterior superior iliac crest and sweep them down along the inguinal canal toward the ipsilateral scrotum while standing on the ipsilateral side of the child or at the feet of an infant, always maintaining the tension in the mass. Mahmood et al. [36] found that traction on the scrotum, or labia majora, helps align the long axis of the hernia sac with the axis of the inguinal canal. Subsequently, apply pressure to the hernia neck on either side using the right index finger and thumb at the ipsilateral internal ring level. It assists in the alignment and maintenance of the external and internal rings, in addition to providing traction on the scrotum. It is beneficial to maintain the alignment and openness of the internal and external rings. Lastly, while maintaining constant pressure on the bottom of the hernia contents, gently walk your left fingers up the groin toward the internal ring, keeping the left hand at the apex of the mass and the right index finger and thumb at the level of the internal ring. The hernia contents will progressively dissolve into the internal ring after taking several minutes to be successful. To confirm whether the hernia has been reduced, compare it to the contralateral side. Sedation may be implemented in the event that this approach proves unsuccessful or the child experiences difficulty enduring it. It is not advisable to reduce the intestine under general anesthesia, as it is possible for the bowel to be injured or for the gangrenous bowel to be reintroduced into the peritoneal cavity without being recognized [13, 28, 37]. The use of sedatives alone may be sufficient to facilitate spontaneous reduction. We advise that the child be monitored in the hospital for 24 hours following a challenging reduction, as gangrenous colon reduction has been documented. Delay the definitive repair of the hernia for a minimum of 24 to 48 hours to allow the edema to subside [7, 37].

2.12 Anesthesia

There have been numerous anesthesia technique combinations that have been reported for the repair of neonate inguinal hernias. These include general anesthesia with or without a regional block, as well as a spinal block or caudal block alone or in conjunction with sedation. However, general anesthesia is the most frequently employed anesthetic technique performed in children, as it possesses many benefits, such as optimal surgical conditions, and is also a technique well-known to clinicians who are frequently involved in the care of neonates [38].

Nevertheless, general anesthesia has been demonstrated to pose substantial risks for neonate inguinal hernia surgery, including prolonged postoperative ventilation and airway complications [38, 39]. This agrees with Massoud et al., who reported a retrospective study of 485 neonates who underwent hernia surgery with general anesthesia. The review revealed an overall respiratory complication rate of 9%, which increased to 35.5% in babies under 45-week postmenstrual age at the time of surgery [38, 40].

Something similar was found in another study conducted on 263 neonates who underwent inguinal hernia surgery. The study revealed an overall postoperative ventilator dependence of 8.3%, reaching 14.7% in infants who underwent the procedure prior to discharge. It has been reported that there is a 25% postoperative ventilator dependence [38, 41].

However, the use of regional methods in conjunction with general anesthesia offers the benefit of decreasing the amount of anesthetic agents and the need for opioids. This is particularly important for term and preterm neonates who are at risk of opioid-induced ventilatory impairment. The addition of caudal anesthesia to general anesthesia has been proven to lower postoperative pain and the amount of opioids that are required after urological surgery in pediatric patients, according to research that was conducted on these patients [38, 42]. A meta-analysis of pediatric inguinal hernia repair conducted in 2023 indicated that there was no significant difference in postoperative pain ratings or rescue analgesia between caudal and nerve block or wound infiltration [38, 39, 42].

The addition of caudal anesthesia to general anesthesia has been proven to lower postoperative pain and the amount of opioids that are required after urological surgery in pediatric patients, according to research that was conducted on these patients [38, 42]. Nevertheless, a meta-analysis reported no significant difference in postoperative pain ratings or rescue analgesia between caudal and nerve block or wound infiltration [38, 39, 42].

Additionally, the majority of full-term neonates and older children undergo the same procedure following hernia surgery. The acceptable age for same-day hernia surgery on an ex-premature neonate is a topic of debate. According to Coran et al., a study demonstrated that preterm infants who were born before 41 to 46 weeks postconceptional age and had a history of neonatal apnea were at an increased risk of developing postoperative apnea. Another extensive study, which employed advanced monitoring techniques to monitor postoperative breathing disturbances, discovered that neonates under the age of 44 postconceptual years were at an elevated risk of experiencing clinically significant episodes of postoperative apnea. In 1995, prospective studies conducted a combined analysis and determined that the incidence of postoperative apnea was not less than 1% with 95% statistical confidence until 56 weeks for a 32-week premature infant and 54 weeks for a 34-week premature infant [7].

2.13 Operative technique

Open-inguinal hernia repair is still the standard approach at present [43]. Nevertheless, the laparoscopic approach is becoming more popular in practice [44]. In 2021, the results of two systematic reviews showed that there is no superiority between the two methods since operation time and complication and recurrence rates are the same for each one [43].

2.14 Open repair

Nowadays, open herniorrhaphy remains the gold standard for primary inguinal hernia repair [45].

The open repair of an indirect inguinal hernia (OHR) in children centers on high ligation of the hernia sac (internal inguinal ring) (Figure 3). A transverse inguinal crease incision is used. The inguinal canal is more lateral than one might expect, a finding made apparent with laparoscopic hernia repairs. It is necessary to open the Scarpa fascia and identify the external oblique aponeurosis. This aponeurosis is opened in the direction of its fibers. It is important to be careful to protect the ilioinguinal nerve, which provides cutaneous sensation to the skin of the anterior thigh. Next, carefully separate the anteromedial hernia sac from the cord structures. The sac may extend down into the scrotum. The sac is clamped after ensuring the absence of the vas and testicular vessels, divided, and followed proximally to the internal inguinal ring, where it is ligated with a doubly absorbable suture. The distal sac should be dilated extensively, but it is unnecessary to remove it. If a hydrocele is present, it is evacuated; however, it is not necessary to perform an excision of the hydrocele sac. In cases of large sacs, they may be everted behind the cord, which is commonly called the bottle procedure. The entire sac can be resected following high ligation in the event of a blind-ending sac. It is uncommon for minors to require formal floor restoration. Inversion ligation is comparatively straightforward to perform after the placement of a proximal purse-string suture in the presence of a sliding hernia [9].

As we have mentioned, there are many differences in the approach to hernia surgery between females and males. In females, it tends to be simpler than in males due to the absence of the necessity of preserving a spermatic cord. The process starts with the identification of the hernia sac and its inspection for contents.

The sac frequently houses the ovary, tube, or mesosalpinx. If the sac is vacant, it is divided between clamps. Following cauterization of the wound’s margins, the distal capsule is reinserted into the cut. The proximal sac is dissected out to the internal ring, contorted, and doubly ligated. The transversalis fascia is then approximated to the shelving edge of the inguinal ligament, and the internal ring is closed using one or two sutures. The inguinal ligament is then closed in the standard manner. According to a study, it is imperative to routinely expose the sac prior to twisting and ligation, as up to 40% of indirect inguinal hernias in females have a sliding component (Figure 4). In the event that the fallopian tube is not readily visible, certain surgeons will apply traction to the round ligament to identify the tube prior to ligating the sac. Additionally, refrain from performing the Bastianelli maneuver, which involves the routine attachment of the sac and the round ligament to the conjoint tendon to restore the uterus’s normal support [34].

No attempt should be made to dissect the fallopian tube from the sac if it is identified as a sliding hernia in the sac wall. Rather, it employs a purse-string closure to close the sac above the fallopian tube, reduce the sac into the internal ring, and close the internal ring with one or two sutures, a procedure referred to as the Bevan repair [7, 46]. Open unilateral hernia correction is the standard of care for adolescents with a unilateral inguinal hernia; contralateral exploration protocols are unnecessary [46, 47].

Contralateral exploration is associated with risks, and not all patent processus vaginalis develop into clinically pertinent hernias; this may be considered an unnecessary surgical risk [46, 48].

2.15 Laparoscopic repair

Since 1975, minimally invasive surgery has been shown to be feasible and safe for pediatric patients. Laparoscopic surgery was first used to treat a small bowel obstruction [49]. El-Gohary in 1997 described laparoscopic repair of inguinal hernias in pediatric patients [49]. Operation was initially performed only in female patients because the safety of the vas and vessels is of concern in males. Monteput and Esposito [50] were involved in the repair of inguinal hernias in male children and were the first to use laparoscopy using an intracorporeal purse-string suture to close the inguinal ring. According to a literature review by Smith et al., Schier described intracorporeal Z-suture closure first in girls only (1998) [33] and then in boys (2000) [51, 52]. Chan and Tam described intracorporeal hydrodissection as a technique to prevent damage to the vas and vessels in males [53]. Also, other modifications of the intracorporeal method include the incision of the peritoneum [54], using it to cover the patent processus vaginalis [55], or making an excision of the sac laparoscopically [56].

Prasad et al. [57] described the use of extracorporeal suturing. After that, there have been multiple changes in medical practice to make the extracorporeal suture more accessible from a technical point of view [58]. Hydrodissection has used both intracorporeally and extracorporeally [59]. The latest improvements are related to the reduction in the number of incisions required to make the surgery [60]. Diagnostic laparoscopy has been used to confirm the hernia’s presence in order to make a smaller incision for an otherwise relatively standard open repair [61].

The laparoscopic method includes several benefits. A cohort study where children underwent laparoscopic herniotomy reported similar pain scores, complications, and recurrence as open herniotomy. Similarly, they reported excellent results in the same age group, with a mean age of 19.1 months in phase I and a mean age of 17.6 months in phase II. In literature reports, recurrence rates are similar between the two studied laparoscopic methods [62].

Literature recommends that the patient be positioned in the Trendelenburg position. The monitor is situated at the foot of the operating table, while the surgeon and assistant are situated at the top of the table. CO₂ is insufflated into the abdomen at a pressure of 5–8 mmHg through an umbilical incision, and a 3-mm trocar is inserted. Two 2-mm apertures are positioned superiorly and medially to the anterior apical iliac spine in telescopic vision [63, 64].

The internal aperture of the hernia is verified by examining the contralateral side. Up to 40% of cases exhibit a contralateral patent processus vaginalis. The decision to close these during the same operation is a matter of debate, as not all of them will develop into a clinical hernia in the future, potentially exposing certain patients to superfluous operative risk. However, the majority of the parents ask for its repair [63, 64].

2.16 Intraperitoneal purse-string closure

The secure application of a purse-string suture is facilitated by the subperitoneal injection of normal saline for boys, which separates the vas deferens and testicular vessels from the peritoneum. A laparoscopic grasper is used to lift the peritoneum that covers the testicular vessels and vas deferens [28].

The peritoneum is elevated away from the vas deferens and testicular vessels by injecting 2 mL of normal saline and using either normal saline or local anesthestic to conduct hydrodissection. A needle is introduced, and the space beneath the distended peritoneum is entered under visual observation. To guarantee the appropriate isolation of the vas and testicular vessels from the peritoneum, saline is injected laterally around the ring and subsequently medially. The injector is subsequently withdrawn. Certain surgeons also employ a diathermy hook to diathermize or incise the collar of the hernia sac. As the literature says, this has been demonstrated in a rabbit model to produce an even more lasting repair [28].

Coran et al. [28] affirm that the technique should be implemented with a non-absorbable monofilament suture that is introduced into the peritoneal cavity by passing it through the abdominal wall. The purse-string suture is initiated at the 2 o’clock position of the internal hernia opening. As they say, the needle should be observed to traverse the subperitoneal space, free of the vas and testicular vessels, with each successive bite of the peritoneum around the hernia ring.

2.17 Burnia technique

Authors such as Mendoza et al. [65] emphasize that the burnia technique has become a very recommendable surgical treatment for inguinal hernias in girls, as its advantages offer better postoperative results, the chance to revise the contralateral inguinal canal, and also better esthetic results. Nevertheless, it is necessary for further investigation to establish it as a gold standard of surgery, as it requires extensive experience to be conducted efficiently.

According to Mendoza et al. [65], “the Burnia technique is performed with the patient in the supine position and using laparoscopic materials such as a 3.5 and 5.3 mm 30° lens, as well as laparoscopic forceps and monopolar energy.” The Hasson technique is used to make a 0.5-cm incision in the umbilical region. It starts with a disposable 5-mm trocar that is used to insert the laparoscopic vision lens. CO₂ is used to produce pneumoperitoneum, with different pressures correlated with the age of the patient but usually between 10 and 12 mmHg. It is important to make a panning of the abdominal cavity and inguinal region to identify where the lesion is located and to assess the contralateral side. Next, a second cut is made on the right flank for a second 3-mm trocar. Then, a work clamp with a 3-mm monopolar connector is introduced to find vaginal peritoneum with the lesion. Then, the hernial sac is pulled away from the peritoneal wall with the Babcock fórceps and without content. When the procedure is finally done, the pneumoperitoneum is evacuated, and the trocars are removed under direct vision [65].

2.18 Alternative technique

On the other hand, the flip-flap technique is an alternative approach that entails an incision in the peritoneum that is 1 cm lateral to the internal inguinal ring. In the manner of a trap door, the hernia orifice is concealed by raising a flap of peritoneum and flipping it across to the internal inguinal ring. A continuous suture should be used to secure the closure of the hernia ring between the free border of the peritoneal membrane and the contiguous hernia ring. The closure of extensive hernias is achieved without tension through the use of a peritoneal membrane [21, 28].

2.19 Extraperitoneal closure

The extracorporeal approach is about placing a suture circumferentially around the internal ring and tying the knot using percutaneous techniques. There have been many variations of this approach. Ostlie and Ponsky reviewed the literature and stated that there was insufficient evidence to support one approach over another [9]. An umbilical incision is made to introduce a 3-mm telescope into the peritoneal cavity, and pneumoperitoneum is established. Under telescopic guidance, a stab incision is made in the lower abdomen, midway between the umbilicus and suprapubic tubercle, to introduce a 2- or 3-mm grasper. Position this port on the ipsilateral side of the hernia; however, the authors consistently position it in the left lower abdomen [28].

Next, it is required to make a small stab wound just at the 12 o’clock position of the internal inguinal ring lateral to the internal inguinal ring. Utilize a 25-gauge finder needle to perform a hydrodissection by first performing it laterally and then medially through the stab incision. Inject either normal saline or a local anesthetic to separate the peritoneum from the vas deferens and testicular vessels. A deeper incision is made in the preperitoneal compartment [28].

To assist in the creation of scar tissue and increase the durability of the repair performance, thermal energy is applied through a stab incision at this point around the internal ring [28].

Place a spinal needle through the stab incision at the 12 o’clock position and pass laterally around the internal ring in the hydrodissection plane, over the cord structures. Use a Maryland dissector to assist in lifting the peritoneum off the cord structures while passing the spinal needle. After the spinal needle has passed over the cord structures, it should be pushed through the peritoneum into the abdominal cavity. The looped monofilament suture is then pushed out partially from the needle, and the needle is removed, leaving the suture in place [21, 28].

To access the prior hook entrance point in the peritoneum, it is recommended to re-insert the hook into the anteromedial portion of the preperitoneal region. Dissect the medial semicircle of the internal inguinal ring in the same way as previously. Back into the peritoneal cavity, the hook goes. A suture is passed through the hook’s eye. The suture will fully wrap the internal inguinal ring when the hook is withdrawn. By compressing the distal hernia sac, the pneumoperitoneum may be freed. Reintroducing pneumoperitoneum ensures that the hernia closure is airtight when the circumferential suture is knotted extracorporeally [21, 28].

2.20 Robotic repair

Additional problems, such as a lack of instrument diversity and an adequate size for younger patients, have slowed the introduction of robotic surgery into pediatric operations. Some have voiced worries about patient safety, citing factors such as the lengthened operation time and limited access for anesthetic patients caused by the size of the robotic system. Robotic surgery has seen a significant increase in its use on juvenile patients during the last decade, despite these restrictions. Robotic pediatric surgical treatments, according to Cundy et al. [66], saw a case volume rise of over 100% between April 2011 and March 2021. The biggest increases were seen in urologic and foregut operations.

The size of the surgical robot and its equipment is the main concern highlighted by Denning et al. [67] in 2020 about robotic surgical technology in pediatric surgery. Compared to the 3-mm instruments often used in conventional laparoscopic operations, the only two sizes of robotic tools that have been authorized for use in pediatrics, 8 mm and 5 mm, are much bigger. Additionally, a 5-mm robotic endoscope was removed due to poor usage; therefore, the only accessible diameters are 12.0 mm and 8.5 mm. The intercostal gap of a youngster weighing 5 kg or less would be too vast for the 8.5-mm scope, even if it could be used with larger children. So, according to the da Vinci surgical platform maker, you should space the ports 8 cm apart. Due to their tiny stature, infants and toddlers would have a hard time covering this distance [39, 68].

2.21 Recurrent inguinal hernias

Recurrent inguinal hernias rarely represent an emergency. This allows the medical professional to assess the best options for treatment. Nevertheless, it is one of the most important concerns after a primary repair. Fortunately, the rise of new techniques and the increasing scientific advances in the matter have allowed the medical community to choose between several approaches that include the open and laparoscopy approach [3, 10, 69, 70, 71].

Literature shows that open repair is the recommended option in cases where the recurrent hernia is concomitant to incarceration, ascended testis, sliding hernia containing the ovary, previous open intra-abdominal surgery, or if the peritoneum at the inner orifice is scarred. However, according to evidence, laparoscopy has gained in popularity for its low rates of complications related to infection. Not only represents a non-invasive procedure but also has improved the incidence of pain, hematomas, and time in the hospital. In our opinion, despite its benefits, it should be taken into account the expertise of the surgeon and the specific case of the patient [72].

2.22 Hernia repair with mesh

In their study, Reistrup et al. said there is a lack of long-term follow-up data and data comparing mesh vs. non-mesh repairs in teenagers. In 2024, researchers looked at data from 4000 groin hernia surgeries and found that open procedures were more common and mesh was seldom employed in teenage cases. There were zero high-quality randomized controlled trials, and the majority of the research was small retrospective cohort studies with no prospective data. Both the mesh and non-mesh procedures had minimal recurrence occurrences (<2%), according to a meta-analysis. All surgical procedures seem to have a tolerable risk of chronic pain, which ranges from 0–11%. A case-based survey demonstrated that for surgeons, surgical approaches to teenagers differed depending on whether they mostly dealt with adult or pediatric patients. It seems that there is a lack of consistency in the treatment of adolescents, depending on the surgeon who is treating them. Pediatric physicians used high ligation, whereas adult surgeons employed either mesh or non-mesh procedures [73].

Due to the high recurrence incidence and inadequacy of standard hernia sac ligation surgery, Chen et al. [74] suggested a biological patch for youngsters aged 13–18. Furthermore, the posterior wall of the inguinal canal should also be repaired and strengthened in order to prevent a recurrence. At present, it is not advocated for children with hernia, from 13 to 18 years old, to be treated with a non-biological synthetic patch (polypropylene) because they are still in the growth and development stage [14]. For children and adolescents, their muscle and fascia tissue will gradually become stronger as the growth and development stage. The absorbable biological materials can rely on their own characteristics to repair defects in the early stages and generate new tissue plates through tissue replacement to prevent the recurrence of hernias in the long term.

Lichtenstein, in 1984, proposed the open “tension-free” mesh repair technique, which is still considered the method of choice for primary inguinal hernia. Lichtenstein hernioplasty with the biological patch was used to treat inguinal hernias in children and adolescents between 13 and 18 years old. This procedure involves placing a biological patch in front of the transversalis fascia to strengthen the back wall of the inguinal canal [19].

2.23 Special cases

3.1 Inherited disorders of connective tissue

Patients with inherited disorders such as Hunter-Hurler, Ehlers-Danlos, and Marfan síndromes present higher rates of inguinal hernia incidence and recurrence. However, this can be prevented by repairing the floor of the inguinal canal with ligation of the sac. In research conducted by Coran and Eraklis, it was found that 36% of the 50 patients with Hunter-Hurler syndrome developed an inguinal hernia. When the high ligation was performed alone, the recurrence rate was as high as 56%. Several studies recommend this technique be combined with floor repair with mesh [9].

3.2 Cystic fibrosis

The prevalence of cystic fibrosis has risen by 6%, while inguinal hernia cases have surged by 15%. The occurrence of missing vas deferens in the overall population ranges from 0.5 to 1%, as indicated by research on vasectomy. Irregularities in the vas deferens in individuals with cystic fibrosis, which can vary from blockages to total absence, are always found and typically affect both sides. Consequently, if the vas deferens cannot be identified, it should prompt an assessment for cystic fibrosis. The absence of the vas deferens is linked to kidney malformation in individuals without cystic fibrosis; therefore, it is advised to assess the upper urinary system in these cases [9].

3.3 Intersex

On very rare occasions, a phenotypic female may be genetically male suffering from androgen insensitivity syndrome or a genuine hermaphrodite. The presence of testicular tissue, sometimes called “the ovotestis,” should prompt a thorough evaluation of any ovary found inside a female patient’s hernia sac. Males who suffer from androgen insensitivity syndrome have smaller testis but no uterus or fallopian tubes. Upon inspection of the gonad, an asymmetric ovotestis is seen, and hermaphrodites may have a fallopian tube inside the hernia sac. It is not necessary to remove an aberrant gonad in either case. It involves removing a little wedge-shaped piece from each pole, replacing the gonad, and fixing the hernia.

3.4 Splenogonadal Fusión

The fusion of splenic tissue with a healthy testis is known as splenotesticular fusion. The typical preoperative diagnosis for a scrotal mass presentation is a testicular tumor. Having an orchidectomy is not required; a frozen section during surgery can give the diagnosis and enable the testis to be saved. The fusion of the spleen and ovaries may also be observed. The fusion of the spleen and gonads can also manifest as a testis that has not descended or a mass within the abdomen. The use of laparoscopy is beneficial for both diagnosing and treating this ailment [9].

3.5 Adrenal rests

Ectopic adrenal tissue is not rare and has been found in 10 of 385 operations for inguinal hernia (2.6%), an incidental finding in each case, appearing as a small mass of yellowish tissue in the apex of the hernia sac. In another series, however, the incidence was 0.2% in 1077 sacs analyzed. The adrenal tissue at this site is likely the result of the attachment of developing adrenal cells to the testis before descent from the retroperitoneum to the scrotum during fetal development [9].

3.6 Postoperative care

Except for newborns who need extended time to be monitored, the majority of patients may usually be sent home within 2 hours following surgical repair. However, while newborns have no activity limitations, older kids should wait to ride bikes or engage in other strenuous physical activities until the discomfort disappears [21].

3.7 Postoperative complications