An abdominal wall hernia is a protrusion (bulge) through a defect (hole) in the muscles of the abdominal wall. It may contain loops of bowel. The commonest site for this on the abdominal wall is the groin. Depending on the exact location in the groin, they can be described as inguinal (direct or indirect), femoral or Spigelian. There is no need to worry about the exact terminology because they can all be repaired with essentially the same operation particularly when the laparoscopic (key-hole) approach is used.

Inguinal (Indirect, Direct)
Femoral
Spigelian

Umbilical, Paraumbilical

Epigastric
Divarication of the recti (separation of the central abdominal muscles), this causes a protrusion in the midline but is not a 'true' hernia and does not carry the risk of bowel becoming trapped within it and thus does not require repair

Obturator
Lumbar
Gluteal
Sciatic
Incisional

Reducible, Irreducible
Strangulated
 
Sliding (retroperitonal contents in sac)

Littre’s (Meckel’s diverticulum in sac)
Richter’s hernia (Stranulated but not obstructed)
Maydl’s (Strangulated above defect)

Complications following hernia repair include:

Recurrence <2% in the short term but this can increase to 5-10% over a long period of follow-up

Bleeding leading to haematoma which usually resolves spontaneously but occasionally may require aspiration/operation

Spermatic cord damage

Wound infection

Urinary retention

Chronic groin pain - this has been found to be more common in patients who have significant pre-operative pain, younger patients and those who have operations for recurrent hernias

Testicular atrophy

A 2 - 4 inch incision is made in the groin.
The hernia is reduced and a mesh inserted to prevent recurrence of the hernia.