Hernias in The Dog              


A Hernia is a ball of tissue or bodily organ that has passed through a tear in a muscular wall.  They are either congenital (heriditary) defect or aquired.  In acquired hernias, there is usually damage caused from some type of trauma for example during birth when the umbilical cord is cut to short or their is an excessive pull on the cord during the cutting process but it may also occur in road accidents.  Most others occur when some normal opening has either failed to close properly or when the opening is stretched or widened by some other means. The main problem with hernias is that, in some cases, organs do pass through the opening and become trapped and/or compressed leading to serious compromise of that organ's function.

The most common type of hernia in a dog is an umbilical hernia; these usually pose no risk, as fatty tissue is usually the only item that protrudes through the opening.  Many umbilical hernias resolve on their own in young animals, or stay small and aren't corrected until the animal is neutered.  Spontaneous closure may occur as late as 6 months of age.  Nearly all types hernias that do not resolve themselves will need to be surgically repaired.  If the hernia is small, surgical correction is often done at the same time as neutering. 

Congenital hernias may involve the diaphragm or the abdominal wall. Hernias involving the abdominal wall include umbilical, inguinal, or scrotal. There are three main types of hernias involving the diaphragm

Peritoneopericardial, in which abdominal contents are found extending into the pericardial sac

Pleuroperitoneal, in which abdominal contents are found within the pleural cavity

Hiatal, in which the abdominal esophagus, gastroesophageal junction, and/or portions of the stomach protrude through the esophageal hiatus of the diaphragm into the thoracic cavity.  Hiatal hernias may be "sliding" and result in clinical signs of reflux esophagitis (anorexia, salivation, and/or vomiting) that may come and go. Definitive diagnosis is done through radiology, and contrast studies are need for confirmation.

Diaphragmatic Herniation
The diaphragm, which separates the chest and abdominal cavities, contracts and relaxes to cause respiration. If a defect or tear occurs in the diaphragm, abdominal organs can move into the chest cavity. While congenital (birth) defects can occur, most often some type of traumatic injury such as jumping down from a great hight - an act which throws the full weight of the abdominal contents forward against the diaphragm when the animal lands on its feet, will lead to a tear in the diaphragm. Clinical signs will vary with the size/severity of the tear and may include trouble breathing, blue lips and gums and inability to get comfortable and death. Diagnosis is based on history, physical examination, X-rays and blood counts with organ chemistries.
Hiatal Hernia
A Hiatal hernia is the result of the abdominal part of the esophagus and/or part of the stomach poking back through the hiatus. The stomach may also fold back into the esophagus. Treatment may be medical or surgical depending on the severity and cause.
Inguinal hernia

These hernias can be congenital or aquired and are often due to Trauma.  It may be caused by the abdominal muscle stretching during pregnancy or atrophy of the abdominal wall due to old age.  These hernias present as skin covered bulges in the groin area.   In the groin area where the leg meets the body, a ring of fibrous tissue exists to allow nerves, blood vessels and in the male dog, the spermatic cord, to pass from inside the body. Most commonly found in females, this ring may be too large and signs of fat or intestine may fill the groin area. In some cases, herniation occurs on both left and right sides. There are three types:
1:  reducible-when the protrusion can be pushed back into the abdomen
2:  Incarcerated-when the bulge cannot be pushed back into the abdomen
3:  strangulated-If the contents of the hernia do not receive adequate blood supply it is called a strangulated hernia.
Umbilical Hernia
A condition in which abdominal contents protrude through the abdominal wall at the area of the umbilicus.  Most present as a soft, ventral abdominal mass at the navel. Dogs, just like humans, have a navel that tends to be flat, smooth and hidden by hair. If this junction either fails to close properly or the mother is too rough tearing off the umbilical cord, the opening can be wider than normal. With smaller hernias, signs include fat or omentum protruding under the skin. With larger hernias, the intestines or liver can protrude. Diagnosis is based on physical examination and X-ray
Scrotal Hernia
This type of inguinal hernia occurs in male dogs and fat or intestine passes clear into the scrotum. Diagnosis is based on physical examination and X-rays.  It is thought to be a heritable condition normally seen as a painless swelling in the scrotum. Treatment is to castrate.
Perineal Hernias
These occur just lateral to the pets anus.  Most common in older male uncastrated dogs secondary to an enlarged prostate. Perianal hernias occur as muscular and connective tissues seem to deteriorate with age in the area between the anus and point of the pelvis nearest the tail. Many dogs will show signs of a swelling near the anus that makes defecation difficult as, in many cases, the rectum and urinary bladder pass into the hernia. This can be so severe as to even block urination or defecation completely. Hernias on both sides also occur in some cases. Diagnosis is based on physical examination and X-rays.
Femoral Hernias
Femoral Hernias are very rare and sometimes occur in performing dogs which have been trained to walk on their hind legs for a considerable amount of time.  The vertical position of the body imposes an unusual strain on the muscles at the fold of the thigh and they give way.  They are always aquired.
Anomalous development of the diaphragm and pleuropericardial membranes that allows herniation of variable amounts of abdominal contents into the pericardial sac. May cause dyspnea, tachypnea, vomiting, diarrhea, cardiac tamponade and congestive heart failure, but some cases are only detected incidentally at postmortem examination. Seen in dogs and cats.
Incisional Hernias.

An incisional hernia occurs in the abdomen in the area of an old surgical scar. A part of an organ in the abdomen, such as the bowel or intestines, protrudes through the weakened area of the abdominal wall.  Incisional hernias are caused by thinning or stretching of scar tissue that forms after surgery. This weakened scar tissue then creates a weakness in the abdominal wall. Excessive weight gain, physical activity that places pressure on the abdomen, pregnancy, straining during bowel movements because of constipation, severe vomiting causes the scar tissue to thin or stretch. Because the abdominal wall is weak, the hernia occurs during abdominal strain.
Blacks Veterinary Dictionary
Saunders Comprehensive Veterinary Dictionary, 3 ed.


Diaphragmatic Hernias (dog)

The large muscle which separates the chest and lungs from the liver and other abdominal organs is called the diaphragm. As the diaphragm contracts and relaxes, it enlarges and compresses the chest cavity. This forces air to move in and out of the lungs.

Types of diaphragmatic hernias

Acquired Diaphragmatic Hernia
An acquired diaphragmatic hernia is a rupture of the diaphragmatic muscle. This is the result of trauma to a dog or cat such as a severe fall or blow to the abdomen. As the abdominal contents such as the stomach and liver are forced against the diaphragm, a tear or rupture of the muscle occurs. Once an opening in the muscle occurs, abdominal contents such as the liver, stomach, or intestines may herniate through the rupture, enter the chest, and put pressure upon the lungs. The diaphragm muscle is now compromised, as it cannot properly expand and contract. In the authors’ experience, most acquired diaphragmatic hernias in dogs are the result of being struck by automobiles.

Congenital Diaphragmatic Hernia
Some puppies are born with an incomplete diaphragm muscle. The muscle was not ruptured as in acquired diaphragmatic hernia described previously, but rather was formed incompletely. This results in an abnormal opening or openings within the diaphragm. Congenital diaphragmatic hernias are uncommon and are diagnosed and managed similarly to acquired diaphragmatic hernias. It appears that German Shepherds and Weimarners are most affected with the congenital forms.

What are the symptoms?
Signs associated with acquired diaphragmatic hernias may occur immediately after trauma or may not be noted for weeks. Signs of congenital diaphragmatic hernias may appear early in life or at several years of age. Difficulty in breathing is the most common symptom. The degree depends on the extent of the damage and may vary from unnoticeable to extremely labored. In severe cases, the tongue, gums, and lips may appear blue. Gastrointestinal upsets such as vomiting or not eating may also be noted when the stomach or intestines herniate through the diaphragm (move through the opening of the diaphragm into the chest). The organs can then become “strangulated” or pinched off by the muscle and other organs.

What are the risks?
The risk depends on the size and location of the hernia within the diaphragm. A small hernia in the diaphragm may go unnoticed and the dog or cat will live a normal life. Dogs with severe hernias in the diaphragm, may develop symptoms quickly and die if left unattended.

What is the management?
Anytime a diaphragmatic hernia is suspected, a veterinary exam should be sought at once. Radiographs (X-rays) will often lead to immediate diagnosis. If a diaphragmatic hernia is suspected, surgical correction is the only treatment and should be attempted as soon as the pet is stabilized.


Umbilical Hernias
Perineal Hernias in the Dog and Cat
Surgery to Repair a Unilateral Perineal Hernia
Inguinal, Umbilical and Diaphragmatic Hernias in Dogs
Perineal Hernias
Hernias in Canines

chloebutton    talabutton

The above information is simply informational. It's intent is not to replace the advice of a veterinarian nor to assist you in making a diagnosis of your pet. Please consult with your own veterinarian for confirmation of any diagnosis. Your pets life may depend on it.