Inguinal hernia is a hernia formed by the protrusion of intra-abdominal organs through a defect in the inguinal region to the body surface, commonly known as “hernia”. The inguinal region is the triangle located at the junction of the lower abdominal wall and the thigh.
Disease description
Inguinal hernia is a hernia formed by the protrusion of intra-abdominal organs through a defect in the inguinal region to the body surface, commonly known as “hernia”. The inguinal region is the triangle located at the junction of the lower abdominal wall and the thigh. Inguinal hernias protrude from the deep ring of the inguinal canal (transversus abdominis fascialis ovalis), located lateral to the inferior abdominal wall artery, and travel inward, forward obliquely through the inguinal canal and then through the superficial inguinal ring (subcutaneous ring), which can enter the scrotum and account for 95% of inguinal hernias. There are two types of inguinal hernias, congenital and acquired. Straight inguinal hernias protrude directly from the inguinal triangle medial to the inferior abdominal wall from posterior to anterior, without passing through the internal ring and barely entering the scrotum, and account for only 5% of inguinal hernias. Inguinal hernias occur in the majority of males. The ratio of male to female incidence is 15:1, with the right side being more common than the left. The incidence of straight hernias has increased in elderly patients, but hiatal hernias are still the most common. With the advent of an aging society, hernias are plaguing more and more elderly people and are prone to serious complications if not treated promptly.
Causes of morbidity
There are many causes of inguinal hernia, mainly reduced abdominal strength, and increased intra-abdominal pressure. Muscle atrophy and weakness of the abdominal wall in the elderly, and even more weakness in the inguinal region, combined with the passage of blood vessels, spermatic cord or round ligament of the uterus, provide a channel for hernia formation. In addition, elderly people tend to have coughing and asthma, constipation, and difficulty in urination due to prostate enlargement, resulting in elevated abdominal pressure, which provides the impetus for hernia formation. The possibility of inguinal hernia should be considered if there is a reversible mass in the inguinal region, i.e. it appears when standing, walking, coughing or working and disappears when resting flat.
Pathogenesis
I. Inguinal hernia: In the early embryonic stage, the testis is located in the retroperitoneum next to the 2nd to 3rd lumbar vertebrae, and then gradually descends, while driving the peritoneum, transverse abdominal fascia and various layers of muscle paths down the inguinal canal at the future inner ring of the inguinal canal and pushing the skin to form the scrotum. The descending peritoneum then forms a sheath, and the testes are placed immediately behind the sheath’s posterior wall. Soon after birth, the sphincter atrophies and atresizes on its own, leaving a fibrous cord behind, except for the part of the scrotum that becomes the intrinsic sheath of the testis. If the ring is not occluded, a congenital hiatal hernia can be formed and the unclosed sphincter becomes the hernia sac of the congenital hiatal hernia. Sometimes, the unclosed sphincter is just a very small duct, which does not present clinically as a hernia, but only as a traffic testicular syringomyelia. If the lower part of the sphincter is atretic and the upper part is not closed, a hiatal hernia may also be induced; if the two ends are atretic and the middle part is not closed, the clinical manifestation is a spermatic sphingomyelia. The right side of the testis descends slightly later than the left side, and the atresia of the sphincter is also later; therefore, right inguinal hernia is more common.
Acquired hiatal hernias are more frequent than congenital ones, and their pathogenesis is completely different. In this case, the peritoneal sphincter is already atretic and a new hernia sac is formed via the groin.
Direct inguinal hernia: The majority of direct inguinal hernias are acquired, and the main etiological factors are incomplete development of the abdominal wall and weakness of the muscles and fascia in the inguinal triangle. When the intra-abdominal pressure increases due to chronic cough, habitual constipation or difficulty in urination, the transverse abdominal fascia repeatedly suffers from the impact of intra-abdominal pressure, resulting in damage and thinning, and the abdominal viscera are gradually pushed forward and protrude, forming a straight hernia.
Clinical manifestations
Inguinal hernia
1. Repeatable hernia: It may vary depending on the size of the hernia sac or the presence or absence of complications. The basic manifestation is the appearance of a reversible mass in the inguinal region, which is small at first and appears only when the patient is standing, working, walking, running, coughing or crying. There is generally no special discomfort, only occasional local swelling and involvement pain. With the development of the disease, the mass may gradually increase in size and descend from the groin to the scrotum or labia majora, making walking difficult and affecting labor. The mass is pear-shaped with a stalk, narrow at the upper end and wide at the lower end. The mass may disappear on its own when lying down or it may disappear by gently pushing the mass outward and upward with the hand and retracting into the abdominal cavity, often with a grunting sound because the contents of the hernia are small intestine. After the hernia mass is retracted, the examiner can use the tip of the index finger to gently reach upward through the scrotal skin along the spermatic cord into the enlarged external ring and ask the patient to cough, then the fingertip feels impact. In some cases of occult inguinal hernia, the presence of the hernia can be determined by this test. The examiner presses the finger against the internal ring of the inguinal canal and then asks the patient to cough hard, the hiatal hernia mass does not appear, but if the finger is removed, the mass is seen to bulge out from the midpoint of the groin from the external superior to the internal inferior. This compression test can be used to distinguish a hiatal hernia from a straight hernia, which can still appear when the patient is asked to cough after the hernia mass is retracted by pressing the finger firmly on the internal ring.
These are the clinical characteristics of a reducible hernia. If the contents of the hernia are intestinal collaterals, the mass is soft, with a smooth surface and a drumming sound on percussion. When retracted, there is often resistance first; once retraction starts, the mass disappears more quickly and often makes a grunting sound when the intestinal collaterals enter the abdominal cavity. If the contents are large omentum, the mass is tough and inelastic, with a turbid sound on percussion and slow retraction. In addition to slightly heavier distension and pain, the main feature of refractory hiatal hernia is that the hernia mass cannot be completely retracted.
2. Sliding hiatal hernia: It is often a large and difficult hernia that cannot be completely retracted. The cecum that slides out of the abdominal cavity often adheres to the anterior wall of the hernia sac. Clinically, in addition to the incomplete retraction of the mass, there are also symptoms such as dyspepsia and constipation. This particular type of hernia should be recognized in clinical work, otherwise the slipped cecum or sigmoid colon may be mistaken as part of the hernia sac and cut open during surgical repair.
3. Incarcerated hernia: It often occurs when there is a sudden increase in intra-abdominal pressure such as strong labor or defecation, and is usually a hiatal hernia. Clinically, it often manifests as a sudden increase in size of the hernia mass with significant pain. The mass cannot be retracted by lying down or pushing it by hand. The mass is tense and hard with marked tenderness. If the embedded content is the greater omentum, the local pain is often mild; if it is an intestinal collaterals, not only the local pain is obvious, but also the signs of mechanical intestinal obstruction such as paroxysmal abdominal cramps, nausea, vomiting, constipation, and abdominal distension. Once the hernia is embedded, there is less chance of self-retraction; most patients’ symptoms gradually worsen, and if left untreated, it will eventually become a strangulated hernia. In the case of intestinal wall hernia, it is easy to be ignored because the local mass is not obvious and there is not necessarily a manifestation of intestinal obstruction.
4, strangulated hernia: the clinical symptoms are more serious. Patients have severe and persistent abdominal pain; frequent vomiting, vomit containing coffee-like blood or bloody stool; asymmetric abdominal distension, signs of peritoneal irritation, diminished or absent bowel sounds; hemorrhagic fluid on abdominal puncture or lavage; isolated distended intestinal mix or tumor-like shadow on X-ray; gradual rise in body temperature, pulse rate, white blood cell count, and even signs of shock.
Direct inguinal hernia
It is mainly a reversible mass in the inguinal region, located just above the pubic symphysis, with a hemispherical shape, mostly without pain or other discomfort. When standing, the mass appears immediately and disappears when lying down. The mass does not enter the scrotum, and because of the wide neck of the hernia, it rarely becomes entrapped. The abdominal wall defect can be directly felt in the inguinal triangle after retraction, and there is a swelling sensation of impact on the fingertips when coughing. The hernia mass can be distinguished from a hiatal hernia by pressing the inner ring with the finger outside the abdominal wall and allowing the patient to rise and cough, which still appears. Bilateral straight hernia and hernia masses are often close to each other on both sides of the midline.
Disease diagnosis
Most inguinal hernias can be diagnosed based on the clinical symptoms of the patient and the physician’s examination. If the hernia is small and the performance is atypical, the diagnosis can be basically confirmed by ultrasound examination.
Treatment
Surgical treatment
There is a misconception about the treatment of inguinal hernia that it is not life-threatening and therefore can be treated or not. However, once the inguinal hernia fails to retract and forms an incarcerated hernia, it can lead to intestinal obstruction, even intestinal necrosis, perforation, and even death, with a mortality rate of about 15%. Treatment of inguinal hernia includes conservative and surgical treatment. Conservative treatment includes hernia belt, hernia brace, Chinese medicine and herbal medicine, etc. These methods can relieve the symptoms or delay the development of the disease, but they cannot cure it, and even some inappropriate conservative treatments can aggravate the disease.
Adult inguinal hernia is not self-healing, and surgery is the only reliable method to treat adult inguinal hernia, which is less likely to recur. Surgery should be selected for an appropriate period for easily recurring hernias, and should be limited to a short period for refractory hernias, while emergency surgical treatment must be taken for incarcerated and strangulated hernias to avoid more serious consequences. Surgical treatment is divided into traditional tissue-to-tissue tension suture repair and tension-free hernia repair techniques, which are currently internationally recognized as tension-free hernia repair techniques, including open surgery and laparoscopic surgery.
I. Traditional surgery
Traditional surgery requires patients to fast before and after surgery, to be bedridden for several days after surgery, to receive fluids, and to be placed under a urinary catheter. Patients have severe postoperative pain, slow recovery, and high recurrence rate, and many patients with cardiac, pulmonary, and cerebrovascular comorbidities cannot operate because they cannot tolerate general anesthesia or hemianesthesia. With the emergence of new materials and technologies, the most widely performed hernia surgery is tension-free hernia repair surgery using artificial materials, which includes open and laparoscopic procedures.
Open tension-free hernia repair: Open tension-free hernia repair was introduced from abroad to China in 1997 and became rapidly popular. It has a low recurrence rate, is less painful, can be done under local anesthesia, and generally requires only 2-5 days of hospitalization, or can even be done on an outpatient basis without hospitalization, and the patient recovers quickly after surgery. The open tension-free hernia repair methods commonly used in China are summarized as follows.
1. flat tension-free repair method (Lichtenstein surgery): Lichtenstein surgery involves suturing the patch to the wall of the inguinal canal and the spermatic cord is led out through the perforation of the patch. Until 1997, it was recognized worldwide as the most classic procedure for hernia surgery. Many hospitals still have many surgeons performing this procedure.
2.Gilbert, mesh plug & patch: This procedure is a combination of mesh plug (1994) and Lichtenstein’s procedure, in which the hernia ring defect is filled with polypropylene rolled into an umbrella shape, then the posterior wall of the inguinal canal is reinforced with a flat patch, and at one time the umbrella filling and the flat patch are not fixed. Later, Rutkow and Robbines suggested to fix the umbrella filling and the flat sheet separately, which is a popular hernia repair procedure abroad and the most rapidly developing procedure in recent years.
The procedure applies a specially designed hernia repair patch, which consists of three parts: an underlying piece placed in front of the peritoneum to repair the pubococcygeal muscle hole; a plug-like intermediate to repair the hernia ring; and a superficial piece to repair the posterior wall of the inguinal canal. This is a method introduced in recent years, and there are many hospitals in China performing such surgery.
4. Tension-free hernia repair method of lining the anterior peritoneal space: This is a new tension-free hernia repair method proposed in 2000, in which the transversus abdominis membrane is opened during open surgery, the anterior peritoneal space is freed and the patch is placed in the anterior peritoneal space to repair the pubococcygeal muscle foramen. With the rapid development of synthetic material science, the patch material has reached the ideal requirement to achieve the overall repair of the three potential defects of the internal ring, direct hernia triangle, and femoral ring, which is the concept of total inguinal repair.
Laparoscopic inguinal hernia repair
(Laparascopic repair of inginal hernia: In 1982, Dr. Ger performed the first laparoscopic inguinal hernia repair in the United States and succeeded in doing so. In recent years, with the improvement of medical devices and surgical techniques, significant progress has been made in laparoscopic surgery. The human abdominal wall is divided into several layers, and the innermost layer is called the peritoneum. The impact on the person can be much reduced if the surgery can be performed without entering the abdominal cavity for therapeutic purposes. Laparoscopic total extraperitoneal repair (TEP for short) can do this with only two 0.5M and one 1M wounds, without entering the abdominal cavity and completely outside the peritoneum, where the hernia pouch is pulled back into the abdominal cavity and the herniated gap is covered with artificial mesh according to endoscopic TV images.
The advantages of this method are as follows: firstly, because of the posterior approach to repair, the anterior peritoneal space can be freed large enough by operating under direct laparoscopic vision; secondly, because of the use of the patch to fully repair and replace the local transverse abdominal muscle membrane at the weakest point, the patch can soon fuse with the abdominal wall tissue to form an extremely tension-resistant union, and because the placed patch is 10M×15M in size, it can cover both hiatal hernia The recurrence rate is low, generally around 1%, and can be further reduced to 0.1% by surgeons with extensive laparoscopic experience. Because of the smaller wound, the postoperative pain is light, the discomfort reaction is small, the recovery is fast, the chance of wound infection is low, and the patient can go home for daily life on the second day after surgery, and can return to work 1-2 weeks after surgery.
In addition, laparoscopic total extraperitoneal repair is most suitable for bilateral inguinal hernias and recurrent hernias. This surgical approach has been accepted by more and more patients because of its advantages of less trauma, faster recovery and lower recurrence, and because the gap between the treatment cost and that of open artificial mesh repair is gradually narrowing.
Rational choice of procedure: Both open and lumpectomy are currently internationally recognized treatments. The open procedure is simple and quick, and local anesthesia expands the indications for surgery, making it a more affordable option. The lumpectomy is a minimally invasive procedure without large incisions and is less invasive. General anesthesia allows patients to have no intraoperative discomfort, less postoperative pain and shorter return to work, but it is more expensive. Whether a patient with inguinal hernia is suitable for laparoscopic or open surgery, the doctor should fully inform the patient of the respective risks and advantages of open and lumpectomy surgery and should be part of the consent form for the surgery, which should be chosen by the patient according to his or her situation combined with the professional advice of the doctor he or she sees.