A hernia is an abnormal opening or a defect in a body cavity that allows structures that are normally contained within the walls of that cavity to protrude or stick out. The abdominal cavity is surrounded by a combination of muscles, bony structures (ribs, spine, and pelvic bones), and fibrous tissue (fascia or aponeurosis) which holds the structures together. There are natural openings in the abdominal cavity which are there to allow structures like blood vessels and parts of the gastrointestinal tract to pass in and out of the cavity. Some of these are places where hernias can occur. For instance, a hernia that occurs where the esophagus enters the abdomen from the chest is called a hiatal hernia, and a hernia that occurs in the area where the femoral blood vessels pass from the abdomen into the legs is called a femoral hernia.
OTHER HERNIA RELATED DEFINITIONS:
HERNIA DEFECT: The actual weakness or opening in the abdominal wall.
HERNIA CONTENTS: The organs or fat coming through the defect.
HERNIA SAC: The lining of the hernia may have an extension of the inside of the abdominal cavity (peritoneum) into which the contents of the hernia can come out and go back inside.
HERNIORRHAPHY or HERNIOPLASTY: The operation to repair a hernia.
HERNIA SIZE: This can refer to either the size of the defect or to how much of the intra-abdominal contents are herniating through the defect – more contents coming through create a larger bulge. Generally, hernias that are not repaired will increase in size over time.
SCROTAL HERNIA: A hernia which has contents that drop into the scrotum is called a scrotal hernia.
REDUCIBLE HERNIA: A hernia which can be pushed back in is called a reducible hernia.
INCARCERATED HERNIA: A hernia which has contents that are stuck outside the defect and cannot be pushed back inside is an incarcerated hernia. This may occur over a long period of time. Sometimes it occurs suddenly and may lead to strangulation of the hernia contents – this may require emergency surgery.
STRANGULATION: An incarcerated hernia in which the blood supply to the contents has been cut off by pressure inside the hernia, leading to death of the tissues.
RECURRENT HERNIA: A hernia which has been repaired before and has come back again.
DIASTASIS RECTI: A separation of the rectus muscles that causes a linear bulge in the mid-line of the abdomen when one sits up.