Hernia Hernia Dr Walid El Shazly MD of General Surgey

Hernia A hernia is a protrusion of a viscus or other structure beyond the normal coverings of the cavity in which it is contained.

Epidemiology The first record of a hernia is in the Egyptian Papyrus Ebers (1550 BC) when it was regarded as a social stigma. Abdominal hernias are common. They occur at all ages and in both sexes and account for approximately 10% of the general surgical workload.

Classification Congenital Acquired In congenital hernias, there is a pre-formed sac patent processus vaginalis is a good example. Acquired Primary hernias occur at natural weak points, such as femoral canal, lumbar region, umbilicus. Secondary hernias develop at sites of surgical or other injury to the wall e.g. after laparotomy or penetrating injury

Aetiology The two main factors predisposing to hernia are increased intracavity pressure a weakened abdominal wall. In the abdomen, the raised pressure occurs as a result of: heavy lifting cough-chronic obstructive airways disease straining to pass urine-benign prostatic hyperplasia or carcinoma straining to pass faeces-constipation or large-bowel obstruction abdominal distension-which may indicate the presence of an intra-abdominal disorder change in abdominal contents- e.g. ascites, encysted fluid, benign or malignant tumour, pregnancy, fat.

Aetiology A weakened abdominal wall occurs in: advancing age malnutrition-either of macronutrients (protein, calorie) or micronutrients (e.g. vitamin C) damage to, or paralysis of, motor nerves abnormal collagen metabolism. Often, multiple factors are involved. For example, the presence of a patent, congenitally formed sac may not cause a hernia until an acquired abdominal wall weakness or raised intra-abdominal pressure allows abdominal contents to enter the sac.

Inguinal hernia Inguinal hernias account for 80% of all external abdominal hernias. They occur at all ages, but are most common in infants and the elderly. Inguinal hernias are 20 times more common in men than in women, and more frequently occur on the right side.

external oblique aponeurosis

internal oblique muscle

transversus abdominus

Direct Inguinal Hernia

Other causes of groin swelling femoral hernia hydrocele encysted hydrocele of the cord undescended or ectopic testis lipoma of the cord epididymal cyst.

DD of groin swelling(LN)

Complications Irreducible Obstructed Strangulated Inflamed.

Irreducible hernia The contents cannot be returned to the body cavity in this type of hernia. The causes of irreducibility are: narrow neck with rigid margins often in association with a capacious sac (e.g. femoral, umbilical) adhesion formation between the contents and the sac (usually long-standing hernias). Irreducible hernias have a greater risk of obstruction and strangulation than reducible ones.

Obstructed hernia The obstructed hernia contains intestine in which the lumen has become occluded. Obstruction is usually at the neck of the sac but may be caused by adhesions within it. If the obstruction is at both ends of the loop, fluid accumulates within it and distension occurs (closed loop obstruction). The term 'incarcerated' is sometimes used to describe a hernia that is irreducible but not strangulated. Thus, an irreducible, obstructed hernia can also be called an incarcerated one.

Strangulated hernia Ten percent of groin hernias present for the first time with strangulation. The blood supply to the contents of the hernia is cut off. The tissues undergo ischaemic necrosis. If the contents of the sac of an abdominal hernia are not bowel, e.g. omentum, the necrosis is sterile Strangulation of bowel is by far the most common and leads to infected necrosis (gangrene).

Inflamed hernia  The contents are inflamed by any process that causes this in the tissue or organ that is not normally herniated, e.g.: acute appendicitis Meckel's diverticulitis acute salpingitis. It may be impossible to distinguish an inflamed hernia from one that is strangulated.

Investigation Hernia is a clinical diagnosis. Investigations are rarely indicated or valuable. Imaging Herniography. This technique, which involves the injection of contrast medium into the peritoneal cavity and subsequent X-ray, is now rarely used Ultrasound is being increasingly used to assess hernias that are difficult to define clinically, e.g. a Spigelian hernia. CT and MRI have an occasional role in rare pelvic hernias (e.g. obturator hernia).

Investigation Laparoscopy Exploratory operation Unexpected hernias are sometimes discovered at the time of laparoscopy for undiagnosed abdominal pain. Exploratory operation In some infants with a convincing history from the mother, a hernia is not found on clinical examination. Exploratory operation can then be justified.

Principles of management There is a particularly strong argument in favour of operation in those hernias that have a high incidence of complication, inguinal hernia with a narrow neck femoral hernia those that have become irreducible.

preoperative preparation Presenting or predisposing conditions such as Benign prostatic hyperplasia Obstructive airways disease may need treatment before the hernia is dealt with.

preoperative preparation Large hernias that warrant repair require particularly diligent preoperative preparation in order to minimise the risk of the operation and to ensure a favourable long-term outcome. Weight reduction should be encouraged. Smoking is discouraged. Treatment of intercurrent disease (e.g. hypertension, diabetes) is essential.

preoperative preparation Therapeutic pneumoperitoneum is very occasionally necessary for giant hernias-when viscera are in a hernia sac for long periods of time, they lose the 'right of domicile' in the abdominal cavity; replacing them suddenly into the abdomen is associated with the dangers of respiratory embarrassment compression of the inferior vena cava paralytic ileus. These complications can be averted by preparing the patient and the abdominal cavity by repeated intraperitoneal injections of air over the 2 weeks before operation, up to a total of 2.5 L.

Surgical techniques Herniotomy is the removal of the sac and closure of its neck. It is the first step in nearly every hernia repair and in some instances (e.g. infant inguinal hernia-see below) may be all that is required. Herniorrhaphy involves some sort of reconstruction to: restore the anatomy if this is disturbed increase the strength of the abdominal wall construct a barrier to recurrence. Hernioplasty

Type 3 inguinal hernia Inguinal hernia

Herniotomy

Herniotomy

Herniotomy

Lytle repair

Lytle repair

LOCAL TISSUE REPAIR Sholdice

Mc vay repair

Tension free hernioplasty

Strangulation

Richter's Hernia

Maydl's Hernia

Femoral Hernia

Inguinal swellings which may resemble a femoral hernia Inguinal hernia Swelling is above and medial to the public tubercle Saphena varix Compressible Palpable thrill on coughing Femoral artery aneurysm Expanding pulsation Bruit Enlarged lymph node Usually multiple Not fixed on deep aspect and therefore more mobile Seek cause-infection, tumour, lymphoma Lipoma Soft but not reducible Psoas abscess Fluctuant Lateral to femoral artery Associated swelling in the iliac fossa Ectopic testis Empty scrotum

Femoral Hernia

Ventral Hernia

Umbilical hernia Congenital (infantile) umbilical hernia Adult umbilical hernia True umbilical hernia In this condition, the protrusion is through the umbilical scar, everting the umbilicus The cause is often secondary to an increase in the volume of contents of the abdominal cavity-e.g. due to obesity, ascites or large benign or malignant intra-abdominal tumours. Para-umbilical hernia The weakest area of the umbilical scar is at the superior aspect between the umbilical vein and the upper margin of the umbilical ring. It is at this point that a para-umbilical hernia develops. The emerging sac displaces the umbilical scar, which lies below and slightly to one side.

Ventral hernia

Epigastric hernia Three-quarters of epigastric hernias are asymptomatic and found incidentally on physical examination. When symptoms are present they are of two types: local pain-often exacerbated by physical exertion ill-defined pain-epigastric in site, often worse after meals

Incisional hernia Aetiology Preoperative factors Age-the tissues of the elderly do not heal as well as those of the young. Malnutrition protein-calorie malnutrition vitamin deficiency (vitamin C is essential for collagen maturation) trace metal deficiency (zinc is required for epithelialisation).

Incisional hernia Aetiology Preoperative factors Sepsis-worsens malnutrition and delays anabolism. Uraemia-inhibits fibroblast division. Jaundice-impedes collagen maturation. Obesity-predisposes to wound infection, seroma and haematoma. Diabetes mellitus-predisposes to wound infection. Steroids-have a generalised proteolytic effect. Peritoneal contamination (peritonitis)-predisposes to wound infection.

Incisional hernia Operative factors Type of incision-vertical incisions are more prone to hernia than are transverse ones. Technique and materials- tension in the closure impedes blood supply to the wound; badly tied knots can work loose; closure with rapidly absorbable suture material fails to support the abdominal wall for a sufficient time to permit sound union. Type of operation- operations involving the bowel or urinary tract are more likely to develop wound infection. Drains-a drain passing through the wound often results in a hernia.

Incisional hernia Postoperative factors Wound infection-equal in importance with the wrong choice of suture material: there is enzymatic destruction of healing tissues; inflammatory swelling raises tissue tension and impedes blood supply; 5-20% of wound infections result in a hernia. Abdominal distension-postoperative ileus increases the tension on a wound; stitches may cut out. Coughing-generates wound tension. Approximately 40% of incisional hernias occur with a documented episode of wound infection.

Interparietal hernia The hernial sac lies between the layers of the abdominal wall. The cause may be congenital, when there is an associated abnormality of testicular descent acquired in an area of weakness in the lateral aspect of the deep inguinal ring and inguinal canal (when the sac usually communicates with a concomitant indirect inguinal hernia). The classification of such hernias is based on the anatomical location of the sac: properitoneal (20%) interstitial (60%) superficial (20%).

Spigelian hernia This is an interparietal hernia in the line of the linea semilunaris (the lateral margin of the rectus sheath, running from the tip of the ninth costal cartilage to the pubic crest). The hernia is usually at the level of the arcuate line, below which all aponeurotic layers are reflected anterior to the rectus muscle.

Spigelian hernia Symptoms are: Signs are: local pain that is worse on straining lump non-specific lower-quadrant discomfort which needs to be investigated in its own right features of obstruction or strangulation. Signs are: tenderness at the site of the hernial orifice lump which may be difficult or even impossible to feel.

Spigelian hernia Recently, ultrasonography has proved useful in the demonstration of these hernias in patients with convincing histories but who lack clinical signs. Repair is a simple matter of excising the sac and closing the defect.

Obturator hernia In this condition, herniation occurs along the obturator canal, which carries the obturator nerve and vessels out of the pelvis. It is most commonly seen in frail old ladies. The hernia starts as a pre-peritoneal plug and gradually enlarges, taking a sac of peritoneum with it. A loop of bowel may enter the sac and reduce spontaneously. A Richter's strangulation is common.

Lumbar hernia Congenital Acquired primary Acquired secondary-the result of surgical incision. Acquired hernias through an incision for lumbar approach to the kidney are not uncommon; however, with the decline in open renal surgery they are becoming less common.

Sciatic hernia A sciatic hernia is the protrusion of a pelvic peritoneal sac through the greater or lesser sciatic foramen. Clinical features Patients present with discomfort a swelling in the buttock there may be symptoms of sciatic nerve compression. If the hernia is large, there is a reducible mass in the gluteal area, made larger on standing. Herniation of the ureters can cause urinary symptoms. There is an appreciable risk of strangulation. Management Treatment is by excision of the sac and closure of the defect by a transabdominal or transgluteal approach.

Perineal hernia These may be: congenital primary acquired incisional. Primary acquired perineal hernias occur in middle-aged, multiparous women. Their broad pelvis and the muscle-weakening effect of childbirth result in herniation through the pelvic floor. Incisional perineal hernia follows 1% of combined abdominoperineal excisions of the rectum.

Perineal hernia Clinical features Management There is usually a perineal swelling and discomfort when sitting. A soft mass is found in the perineum, which is usually reducible. The wide neck has elastic margins. These hernias rarely have dangerous complications. Management Repair is by a combined abdominal and pelvic approach. The hernia is approached from below, the sac dissected free and reduced into the abdominal cavity. A laparotomy is performed and the pelvic floor repaired from above.