What is a perineal hernia?
The perineal hernia corresponds to a weakness of the perineal or pelvic diaphragm, a set of muscles and connective tissues which constitute a wall normally capable of retaining the pelvic and abdominal organs in the abdominal cavity.
If this wall collapses, organs such as the rectum, bladder, colon, prostate and sometimes even the small intestine pass through it and then find themselves under the animal's skin, forming a mass under it.
What causes a perineal hernia in dogs?
In dogs, perineal hernia is due to partial or total atrophy of the muscles that make up the pelvic diaphragm coupled with weakening of the pelvic diaphragm.
The causes of this condition remain unknown to this day, although several hypotheses have been put forward among:
- poor male sex hormone receptors in the muscles of the perineal diaphragm in some dogs,
- primary degeneration of these muscles,
- increased expulsive efforts during defecation or urination related to prostate disease, anal gland disease, recurrent cystitis or urinary tract obstruction,
- atrophy of the levator tail muscle, linked to a naturally short tail in dogs or tail docking,
- an interruption of the muscular innervation of the pelvic diaphragm,
- a decrease in muscle tone linked to the dog's advanced age.
Uncastrated and elderly males are more affected by perineal hernia, as are certain breeds of dogs such as the Boxer, the Collie, the Boston Terrier, the Poodle, the Bichon M altese, the Bichon Frisé or even the Dachshund .
Perineal hernia in dogs: symptoms
A perineal hernia is usually manifested by the appearance of a mass in the perineum, located in most cases on the right side near the anus.
Its presence can be accompanied by constipation, tenesmus (constant urge to have a bowel movement with painful tension in the anus), decreased appetite and difficulty defecating and/ or to urinate.
Apart from these symptoms, a perineal hernia has no significant impact on the dog's general condition unless:
- the bladder engages in the hernia, which makes the perineal mass very painful for the dog and constitutes a surgical emergency,
- an intestinal loop is involved in the hernia, which causes vomiting and a significant depression of the animal.
Diagnosis of perineal hernia in dogs
The diagnosis of perineal hernia is based on:
- a clinical examination of the dog by the veterinarian looking for swelling in the dog's perineal region,
- a digital rectal examination by the veterinarian, allowing him to assess the tone of the pelvic diaphragm and to highlight the presence of lesions on the organs involved in the hernia,
- imaging examinations (radiography and/or ultrasound) in order to characterize the contents of the hernia sac (precisely identify the organs involved in the hernia),
- blood tests prior to surgical treatment.
What treatment for perineal hernia in dogs?
The treatment of perineal hernia is essentially surgical.
The surgery is generally done in two stages:
- the first step is to identify the organs involved in the hernia to put them back in their anatomical place,
- the second stage consists of a reconstruction of the dog's pelvic diaphragm.
If the procedure is performed on an entire male, the surgeon will "take advantage" of the procedure to castrate the animal. This precaution is intended to reduce the size of the dog's prostate which, when too large, causes excessive straining during defecation, which weakens the pelvic diaphragm.
Surgical treatment is successful in 70 to 80% of cases even if complications or recurrences can sometimes occur.Complications can take the form of surgical site infection or the appearance of transient faecal and/or urinary incontinence in most cases.
After the operation, the dog will have to wear a collar and its owner will have to take care to keep the operated area very clean and that the dog avoids making too much effort during defecation. To do this, the veterinarian may administer laxatives to the dog during its post-operative recovery period.