Indirect Inguinal Hernia

An indirect inguinal hernia enters the inguinal canal through the deep inguinal ring lateral to the inferior epigastric vessels.

The sac follows the course of the spermatic cord in men or round ligament in women and may traverse the superficial ring into the scrotum or labium.

Persistence of the processus vaginalis provides the anatomical basis for congenital indirect hernias, although many become clinically apparent only in adulthood.

A complete indirect hernia extends into the scrotum. An incomplete hernia remains within the inguinal canal.

The swelling usually begins in the groin and may extend toward the scrotum.

It increases with coughing or straining and often reduces when supine.

Large indirect hernias may produce a dragging sensation, discomfort during activity or difficulty with manual reduction.

Acute pain with irreducibility, vomiting or abdominal distension indicates acute incarceration or strangulation.

A groin swelling should not be labelled indirect based purely on examination because clinical differentiation from a direct hernia is imperfect.

Diagnosis is usually clinical.

Ultrasound: useful when the hernia is small or occult.

The definitive anatomical relationship to the inferior epigastric vessels is most clearly demonstrated during laparoscopic repair or cross sectional imaging.

The repair principles are the same as for other adult inguinal hernias.

Symptomatic disease should undergo elective repair.

A minimally invasive posterior repair places mesh across the entire myopectineal orifice rather than simply treating the visible indirect defect.

During TEP or TAPP repair, reduce the indirect sac from the cord structures while protecting the vas deferens and gonadal vessels. A large distal scrotal sac does not always need complete excision if aggressive dissection risks cord injury. The proximal sac must be adequately managed.

During open repair, identify the sac anteromedial to the cord structures, separate it carefully and perform a flat mesh repair of the posterior inguinal floor.

The deep ring may be relatively large, but narrowing it excessively risks injury or constriction of the cord.

Emergency operation is required for suspected strangulation or failed reduction of an acutely irreducible hernia. The bowel within an indirect sac can become compromised rapidly when the neck is narrow.