Crural Hernia: What is it? Classification, Causes, Symptoms, Diagnosis, Treatment, Epidemiology and Perspective

Also called femoral hernia, it is a protrusion of the contents of the abdominal cavity.

Hernias, in general, are a condition that occurs when the contents of the abdomen, usually a part of the small intestine, are pushed down from a weak point in the muscle wall or are torn in the thin muscular wall of the abdomen that is responsible for holding the abdominal organs to keep them in place.

It is caused by the protrusion of a viscera (in the case of hernias in the groin, an intra-abdominal organ) through a weakness in the wall that contains it. This weakness may be inherent, as in the case of inguinal, crural, and umbilical hernias.

The crural hernia occurs when the contents of the abdomen are pushed down from the crural canal, resulting in the formation of lumps in the upper part of the thigh near the groin.

It is estimated that about 10 percent of hernia cases are crural hernias. Performing exercises in the crural hernia results in pain that depends mainly on the movements and aggravates the condition by making it worse.

A crural hernia is more common in women than men. It is often the result of being overweight or obese, lifting heavy objects related to daily tasks and exercise, chronic constipation, and frequent and chronic cough.

The hernia often shows no symptoms; however, a lump is seen near the groin. Total intestinal blockage and strangulation can cause nausea, vomiting, and abdominal pain, in which case the patient should be transferred to the emergency room immediately.

 

Some of the crural hernias may be congenital or present at birth but may go unnoticed until later in life.

On the other hand, the weakness may be caused by a surgical incision through the abdominal/thoracic wall muscles. The hernias that occur through these are called incisional hernias.

Crural hernias occur just below the inguinal ligament when the abdominal contents pass through a natural weakness called the crural canal. Crural hernias are relatively uncommon, accounting for only 3% of all hernias.

Although crural hernias can occur in both men and women, almost all develop in women due to the larger bone structure of the female pelvis.

Crural hernias are more common in adults than in children. Those that occur in children are more likely to be associated with a connective tissue disorder or with conditions that increase intra-abdominal pressure.

Some may be congenital or present at birth but may go unnoticed until later in life. Seventy percent of pediatric cases of crural hernias occur in infants under one year of age.

Classification and types of crural hernia

A crural hernia is broadly classified into four types:

  • Hernia crural reducible.
  • Hernia crural irreducible.
  • Hernia crural obstruida.
  • Strangulated crural hernia.
  • Incarcerated crural hernia.

A reducible crural hernia: occurs when a crural hernia can be pushed into the abdominal cavity, either spontaneously or with manipulation, but most likely, spontaneously.

The intestine can be pushed into the cavity so that the opening recovers and does not create more problems. This is the most common type of crural hernia and is usually painless.

An irreducible crural hernia occurs when a crural hernia is stuck in the crural canal, and external manipulation does not help to correct the hernia. This can cause pain and a feeling of illness.

An obstructed crural hernia: occurs when a part of the intestine is intertwined with the hernia, causing an intestinal obstruction. The blockage can grow, and the hernia can be increasingly painful. Vomiting can also result.

A strangulated crural hernia is a condition that occurs when the herniated segment of the intestine has become crooked, and the hernia blocks the blood supply to the intestine and compromises the function of the intestine; the loop of the intestine loses its blood supply.

Strangulation can occur in all hernias, but it is more common in crural and inguinal hernias due to their narrow “necks.” It can cause nausea, vomiting, and severe abdominal pain with a strangulated hernia.

This is a medical emergency. A strangulated intestine can cause necrosis (tissue death) and gangrene (tissue deterioration). This is a life-threatening condition that requires immediate surgery.

A crural hernia can be reducible or irreducible, and each type can also be presented as one (or both) clogged or strangled.

An incarcerated crural hernia is a condition in which a portion of the intestine can be trapped in the hernia. Incarcerated femoral hernia is also a serious condition and should be addressed immediately.

The term ” imprisoned femoral/femoral hernia ” can have different meanings for different authors and doctors. For example, sometimes, the hernia can get trapped in the canal and is called a fundamental or imprisoned crural hernia.

The term ‘imprisoned’ is sometimes used to describe a hernia (obstructed) irreducible but not strangulated. Therefore, a primary and obstructed hernia can also be called an incarcerated.

Hernia imprisoned a hernia that can not be reduced. It can cause intestinal obstruction, but it is not associated with vascular compromise.

A hernia can be described as reducible if the contents inside the sac can be pushed back through the defect into the peritoneal cavity. In contrast, the contents get stuck in the hernia sac with an incarcerated hernia.

However, the term “incarcerated” always seems to imply that the crural hernia is at least irreducible.

Anatomy

The crural canal lies below the inguinal ligament on the lateral aspect of the pubic tubercle. It is limited by the anterior inguinal ligament, the pectineal ligament on the back, the lacunar ligament medially, and the lateral crural vein.

It usually contains some lymphatics, loose areolar tissue, and occasionally a lymph node called the Cloquet nodule.

The function of this channel seems to be to allow the crural vein to expand when necessary to accommodate a greater venous return of the leg during periods of activity. Crural hernias are more common in women than in men.

Causes and risk factors of femoral hernia

Although, in many cases, it is challenging to discover the exact cause of the femoral hernia, suspected causes may include:

  • Lifting of weighty objects.
  • Effort when urinating, probably due to enlargement of the prostate.
  • Chronic constipation
  • Obesity.
  • Women are often more affected.
  • Chronic cough.

Signs and symptoms

Although, in many cases, the femoral hernia does not present any symptoms, there are some reasons and experiences that help indicate the signs.

They usually present when they are erect as a lump or bulge of the groin, which can vary in size during the day, depending on the variations in the internal pressure of the intestine. The swelling or lump is usually more minor or may not be visible in a prone position.

They may or may not be associated with pain. They often present various complications ranging from irreducibility through bowel obstruction to frank gangrene of the contained bowel.

The incidence of strangulation in the crural hernias is high. Frequently, it has been discovered that a crural hernia is the cause of an unexplained obstruction of the small intestine.

The apparent finding may be a lump in the groin. The urge to cough is often absent, and you should not rely solely on the diagnosis of a crural hernia. The projection is more rounded than the pear-shaped bulge of the inguinal hernia.

Most of a crural hernia lies below an imaginary line drawn between the anterior superior iliac spine and the pubic tubercle (representing the inguinal ligament). In contrast, an inguinal hernia begins above this line.

However, it is often impossible to distinguish the two before the operation.

Diagnosis

The diagnosis is mainly clinical, usually performed through the physical, objective, and subjective examination of the groin to diagnose a femoral hernia. However, in obese patients, images in ultrasonography, computed tomography, or magnetic resonance imaging can help diagnose.

An abdominal x-ray that shows small bowel obstruction in a patient with a painful lump in the groin does not need further investigation.

Several other conditions have a similar presentation and should be considered when diagnosing: inguinal hernia, enlarged lymph node, crural artery aneurysm, saphenous varicella, and psoas abscess.

Treatment

Femoral hernia treatment options depend on the symptoms. All femoral hernias present as a lump approximately in the middle of the thigh or below the inguinal fold.

Femoral hernias that are small and asymptomatic may not require specific treatment. Your doctor may monitor your condition to see if the symptoms progress. Moderate to large femoral hernias require surgical repair, mainly if they cause discomfort.

A thorough examination should be performed to verify if the femoral hernia can be manipulated externally to reposition it in its correct place or if it should be corrected surgically. Ideally, this should be an elective procedure (other than an emergency procedure).

However, due to the high incidence of complications, crural hernias often need emergency surgery.

This surgery is minor and does not involve many risks. However, it can involve risks, such as other surgeries, infection, and reaction to pain medications. Crural hernias, like most other hernias, need surgical intervention for sure.

Femoral hernias are more often found enclosed than other types of hernias, so they should be treated surgically to avoid any medical emergency because this tissue may disappear if left untreated.

Surgery helps relieve this discomfort. Surgical repair consists of repositioning the herniated contents in their place and repairing the defect in the abdominal wall.

The area is stitched, or placed a piece of plastic mesh known as a hernia patch is surgically placed to repair the defect present in the abdominal wall to prevent the recurrence of the hernia.

The following steps can be followed for the prevention of femoral hernia:

  • Avoid constipation by increasing fiber intake and drinking enough fluid.
  • Maintain a healthy body weight
  • Avoid putting too much stress on the abdominal wall.
  • Avoid forcing when urinating or defecating.
  • Avoid lifting heavy objects.

Choose a surgical approach:

While all surgeons perform repairs of open groin hernias, some also perform laparoscopic repairs. In general, surgeons must choose the approach with which they feel most comfortable and experienced.

For surgeons who are equally easy with both repairs, a surgical approach depends on the characteristics of the hernia and the patient. The process described below and the accompanying algorithm reflect the author’s preferences and should not be considered the only approach.

Surgery:

The repair of the surgical hernia is done under general anesthesia. This means that you will be asleep for the procedure and will not be able to feel pain.

The femoral hernia repair can be performed as open or laparoscopic surgery. An available procedure requires a larger incision and a more extended recovery period.

The type of surgery chosen depends on some factors, including:

  • The experience of the surgeon.
  • The size of the hernia and any anticipated complication.
  • Early recovery time
  • Cost.

Some surgeons choose to perform laparoscopic surgery; this uses three to four incisions the size of the “keyhole” (also called minimally invasive surgery) that minimizes blood loss rather than conventional “open” surgery.

With minimally invasive surgery, one or more small incisions allow the surgeon to use a surgical camera and small tools to repair the hernia.

Laparoscopic surgery, for example, involves less pain and scarring than open surgery and a shorter time required for healing. However, it is a more expensive procedure than open surgery.

Open or minimally invasive surgery can be performed under general or regional anesthesia, depending on the extent of the intervention needed. Three approaches have been described for open surgery:

  • Enfoque infrainguinal de Lockwood.
  • Lotheissen’s translingual approach.
  • The high focus of McEvedy.

The infrainguinal approach is the preferred method for elective repair. The translingual process involves dissection through the inguinal canal and risks weakening the inguinal canal. McEvedy’s approach is preferred in emergencies when strangulation is suspected.

This allows better access and visualization of the intestine for possible resection. In any approach, care must be taken to avoid injuries to the urinary bladder, which is often part of the medial part of the hernia sac.

The repair is done by suturing the inguinal ligament to the pectoral ligament using strong nonabsorbable sutures or placing a mesh plug in the crural ring. Care must be taken to avoid pressure on the crural vein with either technique.

Your surgeon will make incisions in the groin area to access the hernia in both surgeries. The bowel or other tissue that protrudes from the femoral area is returned to its correct position.

The surgeon will sew the hole again and can reinforce it with a piece of mesh. The mesh strengthens the wall of the canal. Some “tension-free repairs” procedures are minimally invasive and do not require general anesthesia.

Contraindications to surgical repair:

Inguinal or femoral hernia repair can be performed with minimal morbidity and mortality in almost all patients, including the elderly, who have medical comorbidities (e.g., advanced liver disease).

Most patients enjoy a rapid recovery to presurgical health shortly after surgery.

Therefore, there is no contraindication for the urgent repair of complicated hernias.

However, pregnant women should not have elective inguinal or femoral hernia repair until four weeks after delivery.

For patients who can not tolerate general anesthesia, inguinal or femoral hernias can be repaired under local anesthesia using one of the open techniques.

Mesh placement is contraindicated for patients with an active inguinal infection or systemic sepsis, but groin hernias can be repaired using non-mesh techniques.

Postoperative result:

Patients who undergo elective surgical repair do very well and may be able to go home the same day. However, emergency repair entails a higher morbidity and mortality rate, which is directly proportional to the degree of intestinal commitment.

Femoral hernia in pregnancy

The prevalence of inguinal hernias during pregnancy is low, estimated at 1 in 2,000 patients. Elective repair of an inguinal hernia during pregnancy is usually contraindicated.

Expectant management during the peripartum period has been associated with few serious complications related to the hernia.

In one study, seven women with inguinal hernias were treated non-surgically, and each of them had hernias repaired after delivery.

Although combined cesarean delivery and hernia repair have been reported, elective hernia repair should generally be deferred for at least four weeks after delivery to allow the loose abdominal wall to return to its baseline.

An emergency repair of the hernia may be required during pregnancy if the patient develops severe discomfort or complications, such as acute imprisonment, strangulation, or intestinal obstruction.

In one study, such complications were rare and only accounted for <5 percent of bowel obstructions observed during pregnancy.

Epidemiology

Crural hernias are more common in multiparous women, resulting from elevated intra-abdominal pressure that dilates the crural vein and, in turn, stretches the crural ring.

Such constant pressure causes the preperitoneal fat to impinge on the crural ring due to the development of the crural peritoneal sac.

Perspective

Femoral hernias are usually not life-threatening medical conditions.

However, strangulation of the hernia can be life-threatening and should be treated by emergency surgery. The British Hernia Center estimates that the intestine will only survive approximately 8 to 12 hours after strangulation, making it imperative to seek immediate medical attention if you have symptoms.

The repair itself is very safe with few risks. Most people can return to light activities in two weeks. Most people recover fully within six weeks.

The recurrence of a femoral hernia is very low. The National Health Service (NHS) in the United Kingdom estimates that only 1 percent of people who have had a femoral hernia will have a recurrent hernia.