Special Surgery 29. Inguinal and Femoral Hernias: Symptomatics, Diagnostics, Treatments

I. Definitions, Anatomy and Classification

Hernia: General Definition

Hernia = protrusion of an organ/tissue through a normal or abnormal opening in the wall containing it
Groin hernias = inguinal + femoral hernias
Most common abdominal wall hernias
Main contents: preperitoneal fat, omentum, small bowel, colon, bladder rarely
Mechanism: weak abdominal wall + increased intra-abdominal pressure → protrusion → hernia sac

Important Groin Anatomy

Inguinal canal:

Above inguinal ligament
Deep ring → opening in transversalis fascia
Superficial ring → opening in external oblique aponeurosis
Contains spermatic cord in men, round ligament in women

Hesselbach triangle:

Medial border: lateral edge of rectus abdominis
Lateral border: inferior epigastric vessels
Inferior border: inguinal ligament
Site of direct inguinal hernia

Femoral canal:

Below inguinal ligament
Lateral to pubic tubercle
Medial to femoral vein
Narrow neck → high strangulation risk

Inguinal Hernia

Protrusion of abdominal contents through the inguinal canal region
More common in males
May be unilateral or bilateral
May extend into the scrotum, especially indirect hernia

1. Indirect Inguinal Hernia (Lateral)

Passes through deep inguinal ring
Lateral to inferior epigastric vessels
Follows inguinal canal, may enter scrotum/labium majus
Congenital basis: patent processus vaginalis
Can also become clinically apparent later with increased abdominal pressure

2. Direct Inguinal Hernia (Medial)

Protrudes through posterior wall of inguinal canal
Through Hesselbach triangle
Medial to inferior epigastric vessels
Usually acquired
Due to weakness of transversalis fascia/posterior wall
Less often scrotal than indirect hernia

Femoral Hernia

Protrusion of abdominal contents through femoral canal
Below inguinal ligament
Inferolateral to pubic tubercle
More common in women than in men, but inguinal hernia is still the most common groin hernia overall
Always acquired in practical exam logic
High risk of incarceration and strangulation because femoral ring is rigid/narrow

Useful Classifications

By anatomy

Lateral inguinal = indirect
Medial inguinal = direct
Femoral = below inguinal ligament
Pantaloon hernia = simultaneous direct + indirect hernia

By reducibility

Reducible → contents can be returned into abdomen
Irreducible/incarcerated → cannot be reduced
Strangulated → compromised blood supply → ischemia/necrosis
Obstructed → bowel obstruction from herniated bowel loop

Special forms

Sliding hernia → part of sac wall is organ wall, e.g. colon/bladder
Richter hernia → only antimesenteric bowel wall trapped; strangulation possible without complete obstruction
Recurrent hernia → after previous repair
Occult hernia → symptoms without obvious bulge

II. Etiology, Risk Factors and Symptomatics

Etiology / Pathomechanism

Congenital patent processus vaginalis → indirect inguinal hernia
Aging and connective tissue weakness → direct inguinal/femoral hernia
Weak posterior wall of inguinal canal → direct hernia
Widening/weakness of femoral canal → femoral hernia
Increased intra-abdominal pressure:

Chronic cough / COPD
Constipation, straining, prostatism
Heavy lifting
Pregnancy
Ascites
Obesity

Other risk factors:

Male sex for inguinal hernia
Female sex for femoral hernia
Previous contralateral hernia
Family history / collagen disorders
Smoking, malnutrition, chronic steroid use
Previous lower abdominal surgery

Inguinal Hernia: Symptoms

May be asymptomatic
Groin swelling/bulge:

Appears or increases on standing, coughing, straining
Disappears/reduces when lying down
May be reducible by hand

Groin discomfort, heaviness, dragging sensation
Pain worsens with walking, lifting, coughing or prolonged standing
Indirect hernia may extend into scrotum → scrotal swelling
Large hernia may cause skin irritation, difficulty walking, cosmetic complaint

Femoral Hernia: Symptoms

Often small and clinically subtle
May be asymptomatic until complication
Small firm swelling below inguinal ligament
Usually inferolateral to pubic tubercle
Groin pain or vague medial thigh discomfort
Can present first as bowel obstruction or strangulation

Complications

Incarceration:

Hernia cannot be reduced
Painful fixed swelling
Risk of strangulation

Strangulation:

Blood supply of contents compromised
Severe pain, tenderness, erythema, warmth
Fever, leukocytosis, metabolic acidosis/lactate elevation may appear
Ischemia → necrosis → perforation → sepsis

Bowel obstruction:

Colicky abdominal pain
Vomiting
Abdominal distension
Absent flatus/stool
Mechanical ileus

Femoral hernia has higher incarceration/strangulation risk than inguinal hernia
Richter femoral hernia can strangulate without classic obstruction

Danger Signs

Acute irreducible painful groin swelling
Skin redness over hernia
Peritonitis
Persistent vomiting / bowel obstruction
Fever, tachycardia, shock
These signs → emergency surgical assessment

III. Diagnostics and Differential Diagnosis

Clinical Examination

Most groin hernias are clinical diagnoses
Examine patient standing and lying
Inspection:

Bulge location
Scrotal/labial extension
Skin erythema, scars, previous repair
Visible cough impulse

Palpation:

Cough impulse
Reducibility
Tenderness
Size of defect
Relation to pubic tubercle and inguinal ligament

Auscultation may reveal bowel sounds in large bowel-containing hernia
Always examine both groins
In men: examine scrotum/testis
In women: actively consider femoral hernia in any groin hernia

Direct vs Indirect vs Femoral

Feature	Direct inguinal	Indirect inguinal	Femoral
Relation to inferior epigastric vessels	Medial	Lateral	Below inguinal ligament, not classified by this relation
Anatomic route	Hesselbach triangle	Deep inguinal ring → canal	Femoral canal
Typical patient	Older men, acquired weakness	Young men or any age, patent processus vaginalis	Women, elderly, pregnancy history
Location of swelling	Above inguinal ligament, medial groin	Above inguinal ligament, may enter scrotum	Below inguinal ligament, inferolateral to pubic tubercle
Strangulation risk	Lower	Intermediate	High

Exam caveat: Physical examination cannot reliably distinguish direct from indirect in every patient. The clinically important distinction is reducible vs incarcerated/strangulated and inguinal vs femoral, especially in women.

Imaging

No imaging needed if obvious hernia on examination
Ultrasound:

First-line if diagnosis uncertain
Dynamic examination with standing/Valsalva
Useful in thin patients, women, suspected femoral hernia

CT abdomen/pelvis:

Obese patient or unclear mass
Complicated hernia: obstruction, strangulation, recurrent/large hernia
Emergency setting if diagnosis or bowel viability/obstruction unclear

MRI:

Occult groin pain with negative/equivocal US
Athletes / unclear soft-tissue differential
Rarely needed routinely

Differential Diagnosis of Groin Swelling/Pain

Inguinal lymphadenopathy
Saphena varix
Femoral artery aneurysm/pseudoaneurysm
Lipoma of cord/round ligament
Hydrocele, varicocele, spermatocele
Undescended testis / testicular tumor
Psoas abscess
Adductor tendinopathy, hip pathology, pubic osteitis
Endometriosis of round ligament in women

Preoperative Assessment

Assess symptoms and effect on daily life/work
Assess reducibility and complication risk
Medication review: anticoagulants/antiplatelets
Comorbidities: cardiopulmonary disease, diabetes, smoking, obesity
Identify recurrence and previous repair type:

Previous anterior open repair → posterior/laparo-endoscopic repair preferred if feasible
Previous posterior/laparoscopic repair → anterior open repair preferred

IV. Treatment

General Principles

Symptomatic groin hernia → elective surgical repair if patient fit
Asymptomatic/minimally symptomatic inguinal hernia in men → watchful waiting can be considered
Femoral hernia → early planned surgical repair, even if symptoms are vague or absent
Women with groin hernia → repair usually favored because femoral hernia is more easily missed and strangulation risk is higher
Incarcerated/strangulated/obstructed hernia → urgent or emergency treatment
Truss/support belt is not definitive treatment; only temporary symptom control if surgery unsuitable

Inguinal Hernia: Elective Repair

1. Open Anterior Mesh Repair: Lichtenstein

Common standard open repair
Inguinal canal opened
Hernia sac reduced/ligated depending on type
Flat mesh placed over posterior wall of inguinal canal
Mesh fixed to inguinal ligament and conjoint tendon region
Advantages: can be done under local/spinal/general anesthesia, widely available, low recurrence
Risks: chronic groin pain, nerve injury, hematoma, seroma, infection, recurrence

2. Open Non-Mesh Repairs

Shouldice repair:

Posterior wall of inguinal canal closed/strengthened in multiple suture layers
Best non-mesh technique when done by experienced surgeon
Consider if mesh contraindicated or patient strongly prefers non-mesh repair

Bassini repair:

Conjoint tendon/internal oblique-transversus complex sutured to inguinal ligament
Historical importance; higher recurrence than mesh in routine adult practice

3. Laparo-Endoscopic Repair

Repairs the myopectineal orifice from posterior/preperitoneal side
Covers direct, indirect and femoral spaces with mesh
Useful for bilateral hernias, recurrent hernia after open anterior repair, women, need for faster recovery if expertise available

TAPP = transabdominal preperitoneal repair:

Enters peritoneal cavity
Peritoneum opened
Mesh placed in preperitoneal space over hernia defects
Peritoneum closed over mesh

TEP = totally extraperitoneal repair:

Does not enter peritoneal cavity intentionally
Preperitoneal space created directly
Mesh placed outside peritoneum over myopectineal orifice

Femoral Hernia Repair

All femoral hernias should be repaired unless patient is unfit for any intervention
Reason: high risk of incarceration/strangulation
Mesh repair often used in elective clean cases
Laparo-endoscopic TEP/TAPP is effective because it covers femoral and inguinal defects and avoids missed femoral hernia

Open Approaches

Lockwood infra-inguinal / low approach

Direct access below inguinal ligament
Useful for simple elective femoral hernia

Lotheissen trans-inguinal approach

Through inguinal canal
Allows inspection/repair of inguinal canal region

McEvedy high approach

Good access to preperitoneal space
Useful in emergency/strangulated femoral hernia when bowel assessment may be needed

McVay / Cooper ligament repair

Conjoint tendon/transversus arch sutured to Cooper ligament
Can close femoral canal; historical/tissue repair option

Emergency Management

Indications for emergency surgery:

Strangulation signs
Bowel obstruction
Peritonitis
Skin changes over hernia
Sepsis/shock
Failed safe reduction or recurrent incarceration

Incarcerated hernia without strangulation:

Careful manual reduction/taxis can be considered only if no strangulation/peritonitis and early presentation
After successful reduction → observation + planned repair
Do not force reduction

Strangulated hernia:

IV access, fluids, analgesia
Broad-spectrum antibiotics if bowel ischemia/obstruction suspected
Urgent operation
Open sac → assess bowel viability
Viable bowel → reduce and repair hernia
Necrotic bowel → resection + anastomosis or stoma depending on patient/contamination

Mesh in emergency:

Clean field without bowel resection/contamination → mesh generally acceptable
Contaminated field, perforation or gross infection → avoid permanent synthetic mesh; tissue repair or delayed/selected strategy

Postoperative Complications

Early:

Hematoma, seroma
Wound infection
Urinary retention
Testicular ischemia/atrophy rarely after cord vessel injury
Bowel/bladder/vascular injury, especially laparoscopic or recurrent repair

Late:

Chronic postoperative inguinal pain
Numbness/paresthesia from nerve injury
Mesh infection
Recurrence

Exam-Focused Summary

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, high strangulation risk
Diagnosis is usually clinical; ultrasound/CT/MRI only if uncertain, occult or complicated
Symptomatic inguinal hernia → elective repair; minimally symptomatic men may choose watchful waiting
Femoral hernia → repair even if asymptomatic
Lichtenstein = open mesh; TAPP/TEP = posterior laparo-endoscopic mesh repair
Strangulation/obstruction → emergency surgery, possible bowel resection

Exam focus: The key oral distinction is location. Inguinal hernia is above the inguinal ligament; femoral hernia is below it. Direct is medial to inferior epigastric vessels; indirect is lateral. Femoral hernia is dangerous because it strangulates more often, so repair is recommended even with minimal symptoms.