see also:

• herniae
• groin pain
• hip pain
• undescended testes (cryptorchidism)
• JSLS 2006: Hernias as a Cause of Chronic Pelvic Pain in Women

• 1 male in 5 and 1 female in 50 will eventually develop an inguinal hernia in their lifetime such that only 8% of inguinal herniae are in women
• in women:
  • 68% are on right side; 23% on left; 9% are bilateral;
  • incidence in pregnancy 1 in 1000
  • inguinal hernias are much more difficult to diagnose in women than in men. It is typical for women to have nonpalpable or occult inguinal hernias which often remain undiagnosed and may be a cause of chronic pelvic pain or intermittent spasmodic lower abdominal pain as they are less likely to trap bowel, but often just trap abdominal fat and nerves causing pain
  • indirect inguinal hernia is the most common hernia in women (~5x more common than direct herniae or femoral herniae) and these are congenital and due to nonclosure of the processus vaginalis.
    • most present in the 1st 2 years of life but many still present in adult life:
      • apparently more likely in those with premature births or low birth weight
      • 90% of these girls have bilateral patency of the processus vaginalis, 40% have sliding hernias of the tubes and ovary
      • bilateral cases should raise the question of gender as a minority will have testicular feminization syndrome
  • direct inguinal hernia is acquired and is the second most common inguinal hernia in women
    • to cope with the stress of childbearing, the transversalis fascia is stronger in the floor of the inguinal canal than in men, and hence has protective effect, so direct herniae in females is unusual but may develop in the elderly

• indirect inguinal hernia (IIH)
  • the most common form in children and adults
  • most are congenital although may not declare until later in life
  • thought to be due to defective obliteration of the fetal processus vaginalis
  • more common on the right as the right testis is the last to descend
  • arise at the internal ring where the spermatic cord exits the abdomen and this origin is LATERAL to the inferior epigastric artery
• direct inguinal hernia
  • mainly older adults
  • arise in Hesselbach's triangle formed by the inguinal ligament inferiorly, the inferior epigastric vessels laterally, and the rectus abdominus muscles medially.
  • occur as a result in weakness in the floor of the canal
  • may contain urinary bladder, in which case can be a rare cause of urinary retention
  • controversial as to whether these are more likely in those with straining lifting heavy weights as they also occur in sedentary adults
• femoral hernia
  • account for < 10% of all groin herniae
  • 40% present in emergency with incarceration or strangulation
  • arise in the empty space at the medial aspect of the femoral canal which can get bigger with age and following trauma
  • more common in women - presumably due to less muscle bulk and/or weakness of pelvic floor muscles after childbirth
• pelvic floor herniae
  • rare herniae, which mainly occur in women due to their larger pelvis and the stresses of pregnancy and labour
  • obturator hernia
    • 0.07% of all hernias
    • arise in the obturator foramen following the path of the obturator nerves and muscles
    • protrusion of preperitoneal fat or an intestinal loop through the obturator foramen alongside the obturator vessels and nerve causing pain in their lower pelvis and inner thigh, which radiates into the hip and behind their knee
    • Pain increases when standing, lifting, and crossing the legs
    • 6x more common in women as they have a larger canal diameter
    • in thin elderly patients, may present as a small bowel obstruction rather than as protrusion of bowel
  • sciatic herniae
    • protrusion of a peritoneal sac through the greater or lesser sciatic foramen
    • can cause typical sciatica pain with a negative MRI for disk herniation
    • findings at laparoscopy are a sac in the lateral pelvis that deviates the ureter medially toward or onto the uterosacral ligament

• many are asymptomatic
• examine both lying and standing and with and without Valsalva manoeuvre
• attempt to identify hernia sac as well as the fascial defect from which it is protruding
• for inguino-scrotal herniae:
  • NB. nearly all groin herniae in children are indirect inguinal herniae
  • place fingertip in scrotal sac and advance upwards into the inguinal canal
  • if hernia comes from superolateral to inferomedial, and strikes the distal tip of the finger then it is most likely to be an indirect inguinal hernia
  • if hernia strikes the pad of the finger from deep to superficial, it is more consistent with a direct hernia
  • in women, there is unlikely to be a significant bulge, but look for tenderness over the internal ring and pain that may radiate to labia majora and anterior thigh from involvement of either genital branch of the genitofemoral nerve, the ilioinguinal nerve, or the femoral nerve
  • a bulge felt below the inguinal ligament is consistent with a femoral hernia
• strangulated herniae can be differentiated from incarcerated hernia by:
  • pain out of proportion to examination findings
  • fever or toxic appearance
  • pain that persists after reduction of hernia

• check testes to exclude torsion of testis
• if infant - could it just be a benign hydrocele - can you get above it?
• determine type of hernia
• if patient is not toxic, not unwell and has no signs of peritonitis, then try to reduce it
  • is it reducible or irreducible (incarcerated)
• is it strangulated
• if it is incarcerated or possibly strangulated then:
  • urgent general surgical consult
  • nil orally
  • iv fluids
  • FBE, U&E
  • NG tube
  • consider erect/supine AXR and erect CXR to help exclude perforated bowel
  • consider contrast abdo CT scan if there is still concern of strangulation or incarceration
  • consider iv antibiotics if peritonitis
• if there is no evidence of strangulation of bowel and it is reducible:
  • refer to general surgery outpatients, preferably within 2 weeks
  • ensure patients are informed as to which symptoms necessitate emergent review.
  • if neonatal or infantile then may still warrant admission that day or very early surgical consult as high risk of strangulation
  • if examination findings are difficult to assess, consider referral to ultrasound