Inguinal hernia is the most frequently diagnosed hernia and during their lifetime one third of males are diagnosed with an inguinal hernia. The age distribution is bimodal with the highest incidence in childhood and after 50 years of age. Diagnosis is usually reached through clinical examination of a lump in the inguinal region although some patients can present with intestinal obstruction. Inguinal hernia repair is the only definitive treatment and is one of the most common surgical procedures performed. It is usually performed as an elective procedure in local, spinal or general anasthesia. The repair constitutes of reinforcing the posterior wall of the inguinal canal, often using a polypropylene mesh; either via an open anterior approach or posteriorly from within the abdomen with laparoscopy. The most common complications following a hernia repair are recurrent hernia and chronic ­discomfort but recurrence rates have improved with the use of mesh and laparoscopic techniques. This evidence based review describes the ­epidemiology and etiology of inguinal hernia together with the most common surgical procedures; focusing on recent innovations.

Table I Groin hernias.

Table II Differential diagnosis of a groin hernia.

Table III Advantages and disadvantages of the most common operationtypes.

Table IV The most common short-term complications following inguinal surgery and their frequency according to major studies.

Table V Randomized controlled trials comparing inguinal hernia recurrence rates after Lichtenstein and TEP operations.

Table VI Randomized controlled trials comparing the rates of chronic pain following Lichtenstein and TEP inguinal hernia repairs.

Figure I (A) Anterior view of the right inguinal region. (B) The right inguinal region as seen from the posterior―or peritoneal―approach, as in a laparoscopic hernia repair. The dotted triangle marks the border of the Hasselbach's triangle. The dotted blue circles show the different entrances of the three types of inguinal hernias: the direct/medial, indirect/lateral, and femoral. See text for details. (Illustrator: Fritz H. Berndsen Jr.)

Figure II During examination the scrotal skin is inverted with the finger towards the external ring of the inguinal canal (red circle). The patient is asked to cough which makes the hernia protrude against the examiners fingertip.

Figure III (A)Schematic illustration of the Lichtenstein operation. A polypropylene mesh is placed to reinforce the transversalis fascia and a new deep ring is constructed. Schematic illustration of the TEP (totally extraperitoneal) hernia repair. A preperitoneal space is created between the abdominal wall and the peritoneum. A mesh is placed that covers the three hernia sites. (Illustrator: Fritz H. Berndsen Jr.)