Incarcerated Inguinal Hernia · What Is It, Diagnosis, and More

An inguinal hernia is a defect or weakness in the abdominal wall that allows the passage of abdominal contents through the lower abdominal wall into the inguinal region. In uncomplicated hernias, the content can be reduced back into the abdomen by pressing on the hernial sac. However, sometimes the contents cannot be pushed back in, leading to incarceration, since the contents are “locked out” of the abdomen. This results in decreased venous and lymphatic flow and, as a consequence, swelling of the incarcerated tissue. 

Inguinal hernias can be classified anatomically as either direct or indirect. A direct inguinal hernia protrudes medially to the inferior epigastric vessels within Hesselbach’s triangle, which is a weak area in the lower abdominal wall formed inferiorly by the inguinal ligament, laterally by the inferior epigastric vessels, and medially by the rectus abdominis muscle. On the other hand, indirect inguinal hernias occur in the internal inguinal ring, lateral to the inferior epigastric vessels. In males, this is the site where the spermatic cord exits, while in females it’s the site where the round ligament exits the abdomen.  

Indirect inguinal hernias are the most common type of hernia, and they occur more frequently on the right side of the abdomen. Males are more prone to this type of hernias because their inguinal canal is wider due to the descent of the testicles during fetal development, which leaves a natural weak point. Both direct and indirect hernias can present as either asymptomatic, symptomatic, incarcerated, or strangulated. 

An incarcerated inguinal hernia occurs when a hernia becomes trapped and cannot be reduced or pushed back into the abdomen. This occurs because the opening in the abdominal wall is too tight, preventing the herniated tissue from sliding back into place. 

Incarceration is more likely to occur with increased abdominal pressure, which can happen from activities like heavy lifting, straining during bowel movements, chronic coughing, or pregnancy. Over time, increased abdominal pressure can force more tissue into the hernia, making it more difficult to return. Additionally, untreated hernias can enlarge and become more difficult to reduce, leading to incarceration.  

Treatment of incarcerated inguinal hernias depends on the onset of the symptoms. Individuals with an acutely incarcerated inguinal hernia will usually require urgent surgical repair, whereas in individuals with chronically incarcerated hernias, a clinician might attempt to reduce the hernia first. Manual reduction is performed by placing the individual in a Trendelenburg position, lying on their back with the table tilted downwards so the feet are raised, and the head is lowered. This lowers pressure within the abdominal cavity, making it easier to reduce the hernia. Reduction will then be attempted, in which a clinician will put gentle pressure on the hernia to guide its contents back into the abdominal cavity. Sedation and pain medications are usually administered to reduce pain during this process. Reducible incarcerated hernias require elective repair.  

If reduction is not successful, individuals may require consultation with the surgical team to decide further management. Children often require referrals for emergency surgery even before incarceration occurs because they have a high risk of recurrence. Surgical approaches to repair a hernia may vary and are generally categorized as open or laparoscopic repairs.