What is the definition of a hernia?
Protrusion of contents through a defect in the wall of the cavity in which it normally ties
How are hernias anatomically classified?
Congenital or Acquired (degenerative (incl. hormonal), traumatic, iatrogenic)
Type of contents (intestinal, omental)
What is the difference between a true and a false hernia?
True hernia= CONGENITAL and surrounded by peritoneal sac
If hernia contents is readily manipulated into the cavity it is ________.
If the contents of a hernia is fixed into an abnormal location, usually due to adhesions, is considerred __________.
When the vascular supply is obstructed the contents is considered ________ and emergency surgery is warrented.
You know the drill
Red= Hernial contents
Blue= Hernia sac
Green= Hernia ring
During a herniorrhaphy, you must first ensure that the hernia content is _____. The content is then returned to it's normal position and the _______ is removed/obliterated. A _____ free closure of the defect using the patients own _____ should be done if possible.
During a herniorrhaphy, you must first ensure that the hernia content is VIABLE. The content is then returned to it's normal position and the REDUNDANT TISSUE is removed/obliterated. A TENSION free closure of the defect using the patients own TISSUE should be done if possible.
Why don't we freshen the edges of a hernia?
There is a greater chance of adhesions forming if you freshen the edges. There are also healing factors at the edges.
In most animals, the abdominal wall will heal if the edges of the hernia ring are directly apposed without marginal resection.
What breeds are predisposed to umbillica hernias? Are they common? What are some defects associated with these hernias?
Airedale Terrier, Basenji, Pekingese
Most common abdominal hernia (usually inherited)
Lots of congenital defects: Cleft palate, Cryptorchidism, cranial abdominal hernia, incomplete sternal fusion, flucosidosis (lysosomal storage disease in Spaniels)
When do you need to treat an umbilical hernia?
If the defect is small (<3mm) or large (>2.5mm) there is little risk of strangulation and you can wait to see if it will close spontaneously (if <6mo), can repair when neutering.
If the defect is finger (intestine)- sized in a small to medium sized dog there is high risk for strangulation and surgery needs to happen right away.
How do you treat an umbillical hernia if it needs to be treated?
Sx: If during neuter extend incision or make elliptical incision over hernia
Dissect the sac and invert it into the abdomen (closed technique) or ligate sac at neck and open it, then close routinely
If incarcerated: Enlarge the ring and dissect the sac free, deal with contents depending on what shape it's in
Close with 2.0 absorbable monofilament (PDS)
A(n)____ inguinal hernia passes through the vaginal process, in males this is called a _____ hernia.
On the other hand, a(n) _____ inguinal hernia passes through the inguinal musculature and is less common.
An INDIRECT inguinal hernia passes through the vaginal process, in males this is called a SCROTAL hernia.
On the other hand, a DIRECT inguinal hernia passes through the inguinal musculature and is less common.
Congenital or acquired inguinal hernia?
More common in males
More common in intact females
Congenital: Males, younger (<2yrs), rare
Acquired: Intact females (Estrogen), middle aged, overweight
When and how do you repair an inguinal hernia in a male? What structures do you need to watch out for when closing?
Close ASAP (don't delay sx)
Make incision over lateral aspect of swelling
Extend the ring if you can't reduce the contents
Reduce the contents
Close the ring
Watch out for Pudenal Artery and Genitofemoral Nerve, don't impinge when closing
What is a scrotal hernia and how do you repair it? Why castrate them at the same time?
Indirect inguinal hernia in the male dog
Incision over herniated tissue
Castrate because faciliates repair, decreases recurrence, decreases incidence of testicular neoplasia, and prevents possibly passing on the defect to offsping(might have genetic component)
When and how should you repair traumatic abdominal hernias? Why are adhesions more common with these types of hernias?
After the patient is stabilized (if possible, not if identified strangulation), wait a few days
If acute: Ventral midline approach (so can expore abdomen and repair and concurrent injuries caused by the trauma)
Use 2.0 monofilament in tension relieving pattern (Cruiciate, Horizonal or Vertical mattress)
If chronic: approach over hernia for better anatomic closure
Adhesions more common bacause they lack a sac
How do you repair a prepubic tendon rupture? What is it often associated with?
Position patient in truncal flexion with rear legs forward
Use tension holding pattern on soft tissue (tendon)
Pre-drill holes in pubis and use these to anchor for closure
Use heavy, strong suture
Alternative: Use mesh to decrease tension
Often associated w/pelvic fractures
When do incisional hernias occur? What are some predisposing factors?
Usually 3-5 days post-op (but any time <7 days)
Increased intra-abdominal pressure (obesity, effusions, pregnancy)
Technical errors (Inappropriate suture, granny knots, slip knots, facial bites <5mm)
Interrupted pattern better if have peritonitis or something like that going on
What are the differentials for incisional hernias?
Seroma (too much dead-space)
If can reduce it's a hernia, if can't might be a hernia but also might be one of the above - use US if unsure
What type of hernia occurs due to weakness and separation of the pelvic diaphragm?
What are predisposing factors for perineal hernias? Why are females less at risk?
Older intact males (90% of all cases)- hormones (weaken pelvic diaphragm muscles), e.g. Relaxin (from prostate), Prostatic disease (more relaxin)
Neurogenic atrophy (can be from prostatic disease)
Chronic straining (constipation, cystitis, prostatitis)
Pekingese, Boston Terriers, Corgis, Boxers
Females have larger, broader, and stronger Levator ani muscles and a better support of the pelvic diaphragm
What 2 possibilities are there if you feel a firm non-reducible painful mass when you're palpating for a perineal hernia?
How do you manage perineal hernias? What are the post‐operative complications of perineal hernias?
Surgery is treatment of choice
Remove fecal material from rectum and express anal glands, put gauze in rectum and purse string
Position patient with legs hung over a padded, elevated table and secure the tail
Anatomic borders: greater trochanter, ischial tuberocity, ilial crest
Sx: Traditional herniorrhaphy + Internal obturator muscle transposition (Preferred)
(Medical mgmt should only be considered if surgery is absolutely not possible and there are minimal clinical signs)
What factors affect reoccurrence of perineal hernias?
Poor tissue strength
Too much tension
Not castrating at the time
In an intact female with an inginal hernia you notice that there is obvious swelling on one side but not the other, should you check the other side when in surgery or is this a waste of time?
Yes, always check because it tends to be a bilateral disease in intact females
What approach is commonly taken to repair a unilateral inguinal hernia in a female? Why?
Avoids mammary tissue, allows you to inspect both sides, provides access to the abdomen for reducing strangulated tissue
Note: Perform one layer closure over ring
What are the types of perineal hernias and where are they located?
Lateral- between Coccygeous and Sacrotuberous ligament
Dorsal- between Coccygeous and Levator ani muscles (RARE)
Caudal - between Levator ani muscle and External anal sphincter (MOST COMMON in CANINES)
Ventral- Bulbocavernosus and Ischiocavernosus muscles (most common in females, but rare)
What are the borders of the perineal diaphragm?
Medial: External anal sphincter/rectuM
Lateral: Sacrotuberous Ligament (important structures for anchoring during sx)
Dorsolateral: Levator ani and Coccygeous Muscles
Ventral: Ischial arch/Internal Obturator Muscle