Hernia

I. Scrotal Hernia

1. Clinical signs

1. Enlarged scrotal sac.
2. Usually non-strangulating and easily reduced.
3. Noticed between birth and the first week of age.
4. Unilateral (most common) or bilateral.
5. Foal is normal acting with uncomplicated hernias.
6. Complicated hernias

1. Associated with rent in the common vaginal tunic [1].
2. Persistent colic, edema of prepuce and scrotum, mechanical trauma to skin over hernia [2].
3. Difficult to manually reduce [2].
4. Loops of small intestine palpable in subcutaneous tissue of scrotum or thigh [2].

2. Diagnosis clinical signs and palpation.
3. Differential diagnosis

1. Strangulation of intestine.
2. Excessive uroperitoneum or peritoneal fluid.
3. Testicular torsion or hematoma - testicle is painful to palpation and firm.

4. Treatment

1. Nonsurgical

1. Most regress or improve within 7-10 days with repeated manual reduction.

2. Surgical [2,3]

1. Strangulated hernias are best handled by a combination of scrotal and midline incisions. This allows for exteriorization of affected bowel and easier resection and anastomosis.
2. Hernia is usually inside tunica vaginalis, but may be subcutaneous.
3. Best (least complications) to remove testicle of affected side, although not absolutely necessary.
4. Manual reduction of bowel, transfixation ligature of spermatic cord, distal emasculation or amputation is performed.
5. The external inguinal ring is closed with interrupted ligatures incorporating distal stump.
6. Wound may be closed 1o or allowed to heal by second intention.

II. Persistent Preputial Ring or Membrane

1. Clinical signs

1. Foal cannot “drop penis” during urination.
2. Urine scald around prepuce and hind limbs.

2. Diagnosis

1. History, clinical signs.
2. Manual examination of prepuce.

3. Treatment

1. Requires short general anesthesia.
2. Resect membrane to expose glans penis. May require partial resection of preputial folds.

III. Umbilical Hernias

1. Standard care (See Umbilical Problems)
2. Rupture during parturition has occasionally occurred.

1. Congenital umbilical hernias may rupture out of hernia at umbilicus at foaling or soon after.
2. Often follows a dystocia.
3. If bowel is not damaged, clean with saline or Lactated Ringers, replace and ligate cord. Stabilize the foal medically and consider if surgical repair of defect is indicated.

IV. Diaphragmatic Hernias

1. Congenital (abnormal closure of the crura).
2. Acquired (most commonly associated with fractured ribs, dystocia, blunt trauma).
3. Characterized by violent intermittent colic and respiratory distress.
4. Diagnosis with x-ray, ultrasound.
5. Surgical repair possible (primary or mesh technique).