Perineal hernia

A perineal hernia happens when the pelvic “support wall” beside the anus weakens and abdominal/ pelvic tissues bulge outward.

It is seen mostly in older, intact male dogs.

Surgery is the definitive treatment; the most common repair uses an internal obturator muscle flap to rebuild the pelvic diaphragm. Castration is usually recommended at the same time to reduce hormonal/prostate-related recurrence risk.

What’s going on inside? The muscles that normally support the rectum weaken or separate. This allows fat, rectum, prostate, bladder, or sometimes small intestine to bulge into the perineal area beside the anus. Dogs may strain because the rectum bends or dilates, creating a painful cycle of constipation and worsening herniation.

Signs owners notice? Common signs include swelling beside the anus, straining to pass stool, constipation, scooting, discomfort, and a “soft bulge” that may change size. If the bladder becomes trapped, the dog may strain to urinate or be unable to pass urine—this is an emergency