Interparietal hernia

An interparietal hernia has a hernial sac that passes between the layers of the anterior abdominal wall. The sac may be associated with, or communicate with, the sac of a concomitant inguinal or femoral hernia.

Varieties include:

• properitoneal (20%) - the sac takes the form of a diverticulum from a femoral or inguinal hernia
• intermuscular (60%) - the sac passes between the muscular layers of the abdominal wall, usually between the external and internal oblique muscles. The sac is usually bilocular. It is associated with an inguinal hernia.
• inguino-superficial (20%) - the sac expands beneath the superficial abdominal wall or the thigh. It is usually, associated with an incompletely descended testis.

Most patients are male. They present with intestinal obstruction due to obstruction or strangulation of the hernia. Swelling is often absent in the properitoneal variety causing the condition often to be missed or diagnosed late. This is one reason for the relatively high mortality associated with this hernia.

Treatment is by operation.