A perineal hernia is a protrusion of intraperitoneal or extraperitoneal contents into the perineum, resulting in the displacement of pelvic and/or abdominal organs (prostate, rectum, bladder, or fat) into the region surrounding the anus through a congenital or acquired defect of the pelvic diaphragm.
Perineal hernia results from weaknesses or defects in the muscular pelvic diaphragm (levator ani and coccygeal muscles) to support the rectal wall leading to herniation of pelvic and/or abdominal viscera into the subcutaneous perineal region.
The first case was reported by a French surgeon called Rene Jacques Croissant de Garengeot in 1743. Perineal hernias may occur posteriorly or anteriorly to the superficial transverse transversus perinei profundus (perineal muscles).
The underlying cause for failure or weakening of the pelvic musculature is unclear at this time. However, many theories are proposed to explain the reason for pelvic diaphragm weakening or failure. Mostly, the condition affects older pets above 7 years of age. Male dogs particularly those that are not castrated are over-represented.
Symptoms Of Perineal Hernia
Non-painful, unilateral, or bilateral swelling beside or below the anus.
Symptoms that arise from the swelling include:
- Rectal Prolapse
- Stranguria, or Anuria
- Change in the tail carriage.
Perineal Hernia Systemic signs:
- Abdominal Pain
- Topical Skin Erosion
- Lethargy/ Depression
Treatment Options For Perineal Hernia
Surgery: There are many different surgical techniques are involved, but the most common treatment consists of two main steps:
- Reduce the herniated contents - This usually involves an abdominal incision to pull organs out of the hernia sac and surgically fused into the body wall so they cannot retreat into the hernia again. This is most commonly performed on the urinary bladder (called cystopexy) and large intestine (called colopexy).
- Repair the hernia - The aim of this is to recreate the pelvic diaphragm using the internal obturator muscle flap technique. A new pelvic diaphragm is created using this surgical procedure with the transposed muscle flap. Mostly this involves using a synthetic mesh to close the defect or suturing muscles in the area together.
- Castration: In conjunction with perineal hernia surgery, castration (desex) of the dogs under the same anesthetic is recommended. The prostates will shrink and this removes the source of excessive hormones that contribute to the development of a hernia.
- Stool Softeners
- A high fiber diet to relieve the strain of defecation.
- Decompression of bladder with a catheter.
Home Remedies For Perineal Hernia
Follow the instructions given to you by your veterinarian for the entire recommended time period. No matter how badly you want relief for your dogs or what you hear from other dog owners, talk with your vet before trying any home remedy.
Make sure to provide plenty of drinking water.
If any specific diet has been suggested to your dog, follow the diet very strictly, and never provide or allow others to give your dog treats or other food.
Follow all of the veterinarian’s instructions and adhere to your dog's drug schedule properly (don’t miss a dose or overdose).
Prevention Of Perineal Hernia
Early castration in dogs not chosen for breeding purposes is recommended as the condition is rarely seen in castrated male dogs.
Early detection is the only way of prevention.
Check with your veterinarian for post-treatment testing and follow-up visits to make certain that the condition is well under control.
Affected Breeds Of Perineal Hernia
Additional Facts For Perineal Hernia
Congenital Perineal Hernia: This is a rare type and caused due to failure of regression of the peritoneal cul de sac of the embryo.
Acquired Perineal Hernias:
Primarily Acquired Perineal Hernias: Intra-abdominal pressure is the main reason for primarily acquired hernias. Female dogs are overrepresented due to the broader female pelvis and the attenuation by pregnancy-induced adaptations acquired by the pelvic floor muscle.
Secondarily Acquired Perineal Hernias: Incisional hernias are secondarily acquired that occur in close proximity to a surgical incision. They are connected with extensive pelvic surgery such as pelvic exenteration and abdominoperineal resection (APR) of the anorectum (used to treat rectal cancers).
Based on location, Four types of perineal hernias have been described- the dorsal, caudal, sciatic, and ventral.
The most common is the caudal type which occurs between the levator ani and the external anal sphincter.
A canine perineal hernia is not life-threatening in itself, but if the extraperitoneal contents such as the bladder or intestine move through the rupture, it may require an emergency response. The displaced organs obstruct urination and these trapped contents may lead to loss of blood supply and strangulation of the bowel. Life-threatening damage may occur if the pelvic contents herniate into this region.
- Digital Rectal Palpation
- X-rays and ultrasound of the abdomen.
- Prostate Gland Investigation / Biopsy
For the majority of cases, the prognosis is excellent with appropriate treatment. Recurrence of the hernia and wound infection is the major problems reported. Recurrence of perineal hernia may occur within a year in 10-15% of the dogs.
Additional complications include fecal or urinary incontinence, rectal prolapse, fistula formation/ perineal abscessation, and sciatic nerve injury (rare).
Rectal prolapse/ eversion can occur immediately after surgery.
When To See A Vet
Contact your vet right away, if you notice any of the following:
- Swelling beside or below the anus.
- Constipation / Tenesmus
- Change in the tail carriage.
Food Suggestions For Perineal Hernia
Diet high in protein, high fiber, and low carb foods.
- Low fat, high protein foods- White-Fleshed Fish, Skinless, White-Meat Poultry, Beans, Peas, and Lentils.
- Protein - Chicken breasts, turkey breasts, liver, ½ Cup Raw Salmon (or cooked).
- Lean Meats, such as Chicken Breast, Sirloin, or Pork.
- High fiber - Beet Pulp, Brown Rice, Sweet Potatoes, and Pumpkin.
- DHA - Mackerel, Salmon, Herring, Sardines, and Caviar.
The prognosis for a perineal hernia is typically good; however, there is a possibility of recurrence following surgery. Rupture of the other side, Infection, and Faecal incontinence are the most common complications that need to be taken care of after surgery.