Direct Inguinal Hernia

A direct inguinal hernia protrudes through weakness of the posterior inguinal wall within Hesselbach triangle, medial to the inferior epigastric vessels.

Hesselbach triangle is bounded by:

• Rectus abdominis medially
• Inferior epigastric vessels laterally
• Inguinal ligament inferiorly

Direct hernias are usually acquired and reflect attenuation of the transversalis fascia. They are more common with advancing age.

The neck is generally broader than that of an indirect hernia, making strangulation less common, although acute complications remain possible.

A broad groin bulge appears with standing or straining and usually reduces readily when supine.

Large direct hernias may produce dragging discomfort but rarely descend deeply into the scrotum.

A direct and indirect component can coexist, producing a pantaloon hernia with the inferior epigastric vessels lying between the two defects.

Diagnosis is primarily clinical.

Ultrasound: use when the presence of a hernia is uncertain.

Imaging can demonstrate protrusion medial to the inferior epigastric vessels but is not required simply to classify an obvious hernia.

Symptomatic direct hernias should be repaired using mesh unless there is a specific reason to avoid prosthetic material.

Lichtenstein, TEP and TAPP are effective approaches.

During posterior repair, the direct sac is reduced from the transversalis fascia and a sufficiently large mesh covers the entire myopectineal orifice.

Large direct defects have an increased tendency to postoperative seroma because a substantial residual space remains after sac reduction. Inversion or fixation of lax transversalis fascia can reduce the dead space in selected large defects.

Do not excise the transversalis fascia aggressively. The objective is durable reinforcement of the posterior wall.

Watchful waiting can be used for minimally symptomatic direct hernia in men, with the same counselling regarding eventual symptom progression as other inguinal hernias.