You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Inguinal hernias are not as common in animals as umbilical hernias, but they do occur and require prompt treatment.

The inguinal canal is a gap between the abdominal muscles in the inside of the groin through which the spermatic cord of males passes to enter the scrotum. . A hernia occurs when abdominal contents such as fat or loops of intestine pass through the space into the inguinal canal. The condition can be on one side (unilateral) or on both sides (bilateral). An inguinal hernia can be recognised by one or more of the following signs :

• A soft swelling in one or both groins. The swelling goes down when the contents of the hernia sac are pushed back into the abdomen
• A hard, painful swelling in the groin. If the contents of the sac can not be pushed back this is a very serious situation because the contents of the sac can become strangulated, and the blood supply to the tissue can be cut off.
• Difficulty or discomfort when walking
• Standing and walking with a wide stance between the hindlegs.
• Reluctance to walk - if it is painful
• Inappetance 
• Vomiting - if abdominal contents eg intestine or urinary bladder are obstructed
• Depression - if abdominal contents eg intestine or urinary bladder are obstructed

Sometimes XRays are needed to identify which abdominal contents are involved in the hernia.

Congenital inguinal hernias (present at birth) are more common in males than in females. The following breeds of dog are reported to be predisposed to develop congenital  inguinal hernias :

• Basenji
• Basset Hound
• Cairn Terrier
• Pekingese
• West Highland White Terrier

Congenital inguinal hernias can disappear by 12 weeks of age because of different rates of growth of tissues, and the relative decrease in size of the inguinal canal.

Inguinal hernias that occur later in life (so-called acquired hernias) are more common in entire middle-aged females, and they are rare in neutered females. For this reason it is thought that female sex hormones may play a role in weakening the gap in the muscle at the entrance to the inguinal canal. Cats can be affected as well as dogs. An anatomical weakness may occur in the inguinal gap through the muscles due to  trauma - eg a sudden increase in abdominal pressure such as during a road traffic accident, jumping up and down on the hindlegs (a party piece for some dogs!) -  or by  stretching of the abdominal muscle wall due to obesity or pregnancy.

In the following breeds acquired inguinal hernia is thought to be an inherited defect :

• Cocker Spaniels
• Dachshunds (polygenic*?)
• Golden Retrievers (polygenic?)

* More than one gene is involved. Affected animals in these breeds should not be used for breeding, and should probably be neutered.

Inguinal hernias are treated by surgical repair - the contents of the abdomen are returned to the abdominal cavity and the gap between the muscles is closed off. During the post-operative period the area is tender and the animal may be reluctant to walk. Sometimes a swelling occurs at the operation site due to collection of blood (a haematoma). Rest is essential during the healing period otherwise rcurrence of the hernia may be a complication - requiring a second repair

.Updated October 2013