This condition is rare. Strangulation is often encountered in untreated cases. Although firm evidence of inherited predisposition is lacking, an affected animal should probably be castrated unless a trauma etiology can be confirmed. The characteristic scrotal enlargement is usually unilateral, The contents of the hernia can often be reduced toward the inguinal canal, especially when the animal is placed on its back, with the hindquarters elevated.
Tumors of the testes may resemble the appearance of a scrotal hernia. Distinguishing them from a hydrocele or other testicular swellings may be accomplished by grasping the upper part of the scrotum between the thumb and finger. If the skin on both sides can be apposed above the swelling with nothing between it but the spermatic cord, the possibility of hernia can be eliminated,Repair of Scrotal Hernia
This repair involves excising the skin over the external inguinal ring, isolating the hernial sac and reducing its contents through the inguinal canal into the abdominal cavity. If castration is intended, a chromic gut ligature of suitable size is transfixed and passed around the spermatic cord and hernia sac as close to the internal inguinal ring as possible. The spermatic cord and vessels it contains are severed distal to the ligature. The edges of the inguinal ring are opposed with stainless steel or other non-absorbable suture and the skin is sutured in the usual manner.
If the dog is not castrated, recurrence of the scrotal hernia is common. When castration is not performed, the hernia is reduced and sutures are inserted in the neck of the sac to obliterate it without constricting the spermatic cord, If the usual dilation of the inguinal canal is present, several sutures may be inserted in the fascia to partially close the opening. Skin is closed in the usual manner; attachment of the skin to underlying deep fascia helps to prevent edema,
These hernias differ from other hernias in that the displaced organs are not usually within a peritoneal sac. A specific cause has not yet been established for perineal hernias and multiple causative agents are most likely. It has been attributed to failure or weakening of the fascia and muscles of the perineum, permitting abdominal or pelvic organs to prolapse into the space created by atrophy or injury of the pelvic diaphragm.
Although perineal hernias have been reported in the birch, it occurs most commonly in intact male dogs over 8 years old, It does, however, occur in young animals, A structural predisposition has been suggested and dogs with rudimentary tails such as Boston Terriers would be more susceptible. Also reported is a hormonal imbalance etiology. This theory is supported by evidence that some dogs with perineal hernia are concurrently afflicted with testicular tumors, prostates enlargement or enlargement of a cystic uterus musculinea.
Constipation has been cited as a factor in perineal hernia but this has not been firmly established as a cause but more often a result of prostatic enlargement.
Most patients are presented for examination because they have been observed straining to defecate. Also, a swelling lateral to and extending from some distance ventral to the anus is a common sign. The hernial swelling is soft and fluctuate and manipulation often results in reduction of contents. If the bladder and prostate are hernial contents then the swelling may be turgid. if the bladder has become incarcerated or strangulated due to distension with urine following herniation, reduction might only be possible by withdrawing urine from the bladder. A perineal hernia may be bilateral, in which case the whole perineal region is swollen and the anus is displaced caudally.