A hernia is the protrusion of an organ or tissue out of the body cavity in which it normally lies.
The most common hernias, by a generous margin, are inguinal hernias, both direct and indirect. Indirect inguinal hernias are more common in the young as it is due to a congenital defect in the processes vaginalis whilst direct inguinal hernias are more common in the elderly as they are cause by mechanical breakdown of the fascia over many years.
Terms used to describe a hernia:
reducible - the hernial contents can be returned to their normal site
irreducible - duh
incarcerated - a.k.a. irreducible; the contents are fixed within the hernial sac
strangulated - incarcerated hernia with ischaemia of contents; often associated with signs and symptoms of intestinal obstruction
complete - hernia sac and contents protrude all the way through the defect
incomplete - hernial contents do not protrude completely
Types of hernias
Common or important hernia types in bold.
pantaloon hernia
incisional hernia - hernia through an incisional site, most often caused by a wound infection
ventral hernia
Richter's hernia - incarcerated or strangulated hernia involving only one sidewall of the bowel. can result in bowel perforation through ischaemia without causing bowel obstruction.
epigastric hernia - hernia through the linea alba above the umbilicus
umbilical hernia - hernia through the umbilical ring, associated with ascites, pregnancy and obesity
intraparietal hernia
femoral hernia - hernia through the femoral ring
Hesselbach's hernia
Bochdalek's hernia
Morgagni's hernia
propertitoneal hernia
Cooper's hernia
inguinal hernias
hiatal hernia (hiatus hernia) - hernia through the esophageal hiatus
Reference: Surgical recall, 2nd edition, by Lorne. H. Blackbourne, published by Lippincott Williams & Wilkins