Inguinal Hernia: The Complete Guide

What is an inguinal hernia?

An inguinal hernia is a protrusion of bowel or fat through a weakness in the inguinal canal, a natural passage in the lower abdominal wall that carries the spermatic cord in men and the round ligament in women. Together with femoral hernia it forms the group of groin hernias. See the complete hernia guide for the big picture.

Types

• Indirect inguinal hernia: the most common at all ages and the type seen in children. Usually congenital — a patent processus vaginalis — and may descend into the scrotum.
• Direct inguinal hernia: an acquired weakness of the posterior wall (Hesselbach's triangle), typical of older men; rarely enters the scrotum and has a lower strangulation risk.
• Pantaloon hernia: direct and indirect components together.

Surgeons use the European Hernia Society (EHS) classification: L (lateral/indirect), M (medial/direct), F (femoral), with defect size 1 (≤1.5 cm), 2 (1.5–3 cm), 3 (>3 cm).

Who is at risk?

• Men (lifetime risk ~27% vs 3% in women).
• Age, with peaks in infancy and after 50.
• Family history, prematurity, previous contralateral hernia.
• Chronic cough, constipation, prostate enlargement, heavy work, smoking, connective tissue disorders.
• Interestingly, lower body mass index has been associated with higher inguinal hernia risk in large studies.

Symptoms

• A groin bulge on one or both sides that appears when standing or coughing and disappears when lying down.
• Heaviness, dragging or burning, worse at the end of the day.
• Pain with lifting, bending or sport.
• Scrotal swelling in men.
• In women the bulge may be small, with pain in the lower abdomen or labia.
• About one third of patients have no symptoms.

More: Hernia symptoms and diagnosis.

Diagnosis

1. Clinical examination standing, with a cough test — sufficient in most cases.
2. Dynamic ultrasound for doubtful or occult hernias, and to exclude lymph nodes, varicocele or hydrocele.
3. MRI for unexplained groin pain or suspected sportsman's hernia.
4. CT for complex cases or suspected strangulation.

Treatment

Is watchful waiting acceptable?

According to HerniaSurge, men with an asymptomatic or minimally symptomatic inguinal hernia may choose watchful waiting, as the strangulation risk is low (under 1 per 1000 patient-years in trials). Most, however, eventually need surgery. Symptomatic hernias and hernias in women should be repaired. Read: Treatment without surgery.

Surgical options

Mesh repair is the recommended standard for most adults:

1. Lichtenstein (open): 5–7 cm incision, tension-free mesh over the posterior wall, possible under local anaesthesia — ideal for elderly or high-risk patients.
2. Laparoscopic TAPP or TEP: three small ports; a large mesh covers all groin openings (direct, indirect and femoral). Recommended especially for bilateral hernias, recurrence after open repair, women, and patients wanting a faster return to activity.
3. Shouldice: a non-mesh suture repair for patients who decline mesh, in specialist hands.
4. Robotic repair in selected centres.

Children are treated differently — sac ligation without mesh. See hernia in children.

Results

• Recurrence after specialist mesh repair is low (under 5% in most modern series).
• Chronic pain (>3 months) affects about 10%, but is significant in only 1–3%, and is lower after laparoscopy with careful nerve handling.
• Other complications: seroma, bruising, temporary urinary retention, temporary scrotal swelling.

See hernia surgery, recovery and hernia mesh.