inguinal hernia

Question 1

definition

Answer 1

An inguinal hernia is a protrusion of abdominal or pelvic contents through a dilated internal inguinal ring or attenuated inguinal floor into the inguinal canal and out of the external inguinal ring, causing a visible or easily palpable bulge.

Question 2

direct and indirect hernias

Answer 2

Indirect inguinal hernias usually occur because of a persistent processus vaginalis and failure of normal closure, which leaves an empty peritoneal sac lying in the inguinal canal. The hernia becomes clinically evident when bowel or other abdominal content fills and enlarges the empty sac, creating a visible bulge. The hernia sac follows the spermatic cord down into the scrotal sac in men, or follows the round ligament in women to the pubic tubercle. Indirect hernias may be congenital (closely adherent to the vas deferens) or acquired (anatomically separate from the vas). Most hernias in women are indirect.

Direct hernias are always acquired and therefore unusual under the age of 25. A direct inguinal hernia occurs because of degeneration and fatty changes in the aponeurosis of the transversalis fascia that constitutes the inguinal floor or posterior wall in the Hesselbach triangle area. The Hesselbach triangle is defined inferiorly by the inguinal ligament, laterally by the inferior epigastric artery and vein, and medially by the lateral border of rectus abdominus. Most direct hernias do not have a true peritoneal lining and do not contain bowel, but mainly preperitoneal fat, and occasionally bladder. However, a large, long-standing direct hernia can extend into the scrotum and can harbour bowel or abdominal content.

Strangulation rarely occurs with a direct hernia because the structural defect in a direct hernia is usually a diffuse weakness and stretching of the inguinal floor tissues, rather than a discrete, sharply defined ring-like defect. Strangulation is more common with an indirect hernia, particularly if there is a narrow neck passing through a tight internal ring. As segments of the intestine prolapse through the defect in the anterior abdominal wall, they cause sequestration of fluid within the lumen of the herniated bowel. This initially impairs the lymphatic and venous drainage, which further compounds the swelling. Over time this can impair the arterial supply and cause ischaemia. Gangrene ensues and, if left untreated, perforation occurs. Peritonitis occurs initially within the sac and then spreads to the peritoneal cavity.

Question 3

position of inguinal hernia

Answer 3

superior and lateral to pubic tubercle
(traditional teaching is superior and medial, but nowadays taught to be lateral)

(femoral artery to inferior and lateral to pubic tubercle)

Question 4

symptoms

Answer 4

• groin discomfort or pain with bulge
• groin mass, irreducible/reducible
• can have other cut abdomen symptoms with strangulated hernia

Question 5

risk factors

Answer 5

male
old age
marfan’s syndrome
ehlers-danlos syndrome

Question 6

investigations

Answer 6

1st:
clinical diagnosis (with palpation etc)

others:

• USS groin
• CT contrast (usually for very obese patients)
• herniography
• MRI groin

Question 7

management

Answer 7

acute: (incarcerated or strangulated)
1. surgical repair
+ prophylactic abx (cefazolin + vancomycin)

ongoing: (small asymptomatic)
1. watchful waiting

ongoing: (large symptomatic)
1. open mesh or laparoscopic repair
+ cefazolin + vancomycin

for recurring:
1. mesh laparascopic repair

for non surgical candidate:
1. truss or observation

Question 8

clinical differentiation of indirect and direct inguinal hernia

Answer 8

The deep ring is an opening in the transversalis fascia at which the inguinal canal begins. It lies at the mid-point of the inguinal ligament. To differentiate, reduce the hernia and place 2 fingers over the deep ring. The patient must then cough. If the hernia is controlled (suggesting that it commences at the deep ring) it is an indirect one; if it protrudes it is direct.

A direct hernia is a defect in the posterior wall (in the transversalis fascia) whereas an indirect hernia protrudes through the internal inguinal ring. During surgery the inferior epigastric vessels can also be the only definite way to differentiate between a direct and an indirect inguinal hernia. This is done by noting the position of the neck of the hernial sack in relation to the inferior epigastric vessels. A direct hernia is medial to the vessels whereas an indirect would be lateral.

BASICALLY: PUT UR FINGERS OVER DEEP RING (mid inguinal point) AND PATIENT COUGH -> IF DOES NOT PROTRUDE MEANS INDIRECT