Special Surgery 29. Inguinal and Femoral Hernias: Symptomatics, Diagnostics, Treatments
I. Basic Definitions and Groin Anatomy
Definition
- Hernia: protrusion of abdominal contents through a weakness/opening in the abdominal wall
- Groin hernias: inguinal hernia + femoral hernia
- Most common groin hernia: inguinal hernia
- Mechanism: abdominal wall weakness + increased intra-abdominal pressure → protrusion → hernia sac
Key Anatomy
- Inguinal canal: above inguinal ligament
- Deep inguinal ring: entrance of indirect inguinal hernia
- Hesselbach triangle: site of direct inguinal hernia
- Medial border: lateral edge of rectus abdominis
- Lateral border: inferior epigastric vessels
- Inferior border: inguinal ligament
- Below inguinal ligament
- Lateral to pubic tubercle
- Medial to femoral vein
- Narrow rigid ring → high strangulation risk
II. Inguinal Hernia
Definition and Types
- Inguinal hernia: protrusion of abdominal contents through the inguinal canal region
- More common in males
- Increased intra-abdominal pressure → abdominal contents pushed through weak inguinal area
- Direct inguinal hernia (medial)
- Through Hesselbach triangle
- Medial to inferior epigastric vessels
- Always acquired in exam logic
- Cause: aging + weakness of posterior inguinal wall/transversalis fascia
- Indirect inguinal hernia (lateral)
- Through deep inguinal ring
- Lateral to inferior epigastric vessels
- Congenital basis: patent processus vaginalis
- May extend into scrotum/labium majus
Etiology / Risk Factors
- Congenital patent processus vaginalis → indirect hernia
- Aging and weakening of abdominal muscles/fascia → direct hernia
- Obesity
- Chronic cough / COPD
- Constipation, straining, prostatism
- Heavy lifting
- Smoking, collagen weakness, family history
Clinical Features
- May be asymptomatic
- Groin swelling/bulge → increases on standing, straining or coughing
- Reducible hernia → contents can be pushed back
- Groin pain, discomfort, heaviness or dragging sensation
- Indirect hernia → may extend to scrotum
Complications
- Incarceration: cannot be reduced → risk of strangulation
- Strangulation: impaired blood supply → ischemia → necrosis
- Obstruction: vomiting + bowel distension + mechanical ileus
- Danger signs: severe pain, redness, nausea/vomiting, fever, peritonitis, shock
Diagnosis
- Usually clinical diagnosis
- Physical examination: inspection + palpation standing and lying
- Cough impulse / Valsalva → bulge becomes visible or palpable
- Assess reducibility, tenderness, skin changes, scrotal extension
- US: first-line imaging if uncertain
- CT: obese patient, occult hernia, recurrence, obstruction/strangulation suspicion
- MRI: unclear groin mass or occult groin pain when US/CT is not diagnostic
Treatment
- Asymptomatic/minimally symptomatic male inguinal hernia → watchful waiting can be considered
- Symptomatic, enlarging or incarcerated inguinal hernia → repair
- Open repair
- Lichtenstein tension-free mesh repair: mesh supports posterior wall of inguinal canal
- Shouldice repair: posterior wall closed/strengthened in 4 suture layers
- Bassini repair: internal oblique/transversalis fascia region sutured to inguinal ligament
- Laparoscopic / laparo-endoscopic repair
- Transabdominal preperitoneal repair (TAPP): enters peritoneal cavity → peritoneal incision → mesh in preperitoneal space
- Totally extraperitoneal repair (TEP): does not enter peritoneal cavity → preperitoneal space created → mesh outside peritoneum
- Useful for bilateral hernia, recurrent hernia after open repair, women, faster recovery if expertise available
III. Femoral Hernia
Definition and Anatomy
- Femoral hernia: protrusion of abdominal contents through the femoral canal
- Below inguinal ligament
- Lateral to pubic tubercle
- Medial to femoral vein
- More common in females than males
- Always acquired in practical exam logic
Etiology / Risk Factors
- Aging + weakness/widening of femoral canal
- Pregnancy
- Obesity or rapid weight loss
- Constipation and straining
- Chronic cough
Clinical Features
- Often asymptomatic until complications occur
- Small firm groin swelling below inguinal ligament
- Swelling/pain worsens when standing or straining
- May cause vague groin or medial thigh discomfort
- May present first with bowel obstruction or strangulation
Complications
- Higher risk of incarceration and strangulation than inguinal hernia
- Incarceration: cannot be reduced
- Strangulation: ischemia → necrosis
- Obstruction: vomiting + bowel distension + mechanical ileus
- Richter femoral hernia: bowel wall strangulation possible without complete obstruction
Diagnosis
- Physical examination: inspection + palpation standing and lying
- Typical site: below inguinal ligament, inferolateral to pubic tubercle
- Women with groin hernia → actively exclude femoral hernia
- US: first-line if uncertain
- CT: obese patient, occult/complicated hernia, obstruction or strangulation suspicion
- MRI: rarely needed; unclear groin mass or occult pain
Treatment
- All femoral hernias require surgical repair if patient is fit
- Reason: high risk of incarceration and strangulation
- Mesh repair often used in elective clean cases
- Avoid permanent synthetic mesh in gross contamination/perforation
- Open repair
- Lockwood infra-inguinal approach: direct low access below inguinal ligament
- Lotheissen trans-inguinal approach: through inguinal canal
- McVay / Cooper ligament repair: tissue repair closing femoral canal
- McEvedy high approach: useful in emergency when bowel assessment may be needed
- Laparoscopic / laparo-endoscopic repair
- Transabdominal preperitoneal repair (TAPP) or totally extraperitoneal repair (TEP)
- Covers femoral + direct + indirect spaces
- Often useful in women because femoral hernia may be missed clinically
IV. Emergency Treatment and Exam Summary
Emergency Surgery
- Indications: strangulation, incarceration with failed safe reduction, bowel obstruction, peritonitis, skin changes, sepsis/shock
- Initial management: IV access + fluids + analgesia + antiemetic
- Suspected bowel ischemia/obstruction → broad-spectrum antibiotics
- Operation: open hernia sac → assess bowel viability
- Viable bowel → reduce contents + repair hernia
- Necrotic bowel → resection ± anastomosis/stoma depending on patient and contamination
Key Distinctions
- Indirect inguinal hernia: lateral to inferior epigastric vessels, through deep ring, often congenital processus vaginalis
- Direct inguinal hernia: medial to inferior epigastric vessels, through Hesselbach triangle, acquired posterior wall weakness
- Femoral hernia: below inguinal ligament, lateral to pubic tubercle, medial to femoral vein
- Femoral hernia = highest strangulation risk → repair even if asymptomatic
- Diagnosis is usually clinical; US/CT/MRI only if uncertain, occult or complicated
- Lichtenstein: open mesh repair
- Transabdominal preperitoneal repair (TAPP) / totally extraperitoneal repair (TEP): posterior preperitoneal mesh repair
- Strangulation/obstruction → emergency surgery, possible bowel resection
Exam focus: Inguinal hernia is above the inguinal ligament; femoral hernia is below it. Direct is medial to inferior epigastric vessels; indirect is lateral. Femoral hernia strangulates more often, so planned repair is recommended.