Hernia — Comprehensive Overview

Definition

Anatomical Classification & Types

Figure: Common hernia sites — Bailey & Love's Surgery, p. 1086

Groin Hernias

Ventral / Abdominal Wall Hernias

Diaphragmatic / Internal Hernias

Pathophysiology

• Age, male sex (for inguinal)
• Obesity, chronic cough, straining, heavy lifting
• Previous surgery (incisional hernias)
• Connective tissue disorders

Clinical Spectrum — Reducible → Incarcerated → Strangulated

Strangulation risk is inversely related to the size of the hernia neck. Femoral hernias strangulate in up to 40% of cases at first presentation; incisional hernias in only ~2%. Umbilical hernias account for ~15% of emergency hernia surgery, with up to 60% showing strangulation at operation. — Sleisenger & Fordtran's GI & Liver Disease

Hiatal Hernia & GERD

1. Displacing the LES above the diaphragm → reduces basal LES pressure
2. Creating a persistent acid pocket in the hernia sac
3. Increasing transient LES relaxation (tLESR) frequency
4. Abolishing the pressure augmentation normally provided by crural diaphragm contraction

Diagnosis

• Physical examination: visible or palpable bulge, cough impulse, reducibility
• Ultrasound: useful for groin hernias, especially in obese patients
• CT scan: gold standard for internal hernias, incarcerated hernias, and complex cases; differentiates hernia type and assesses bowel viability
• Endoscopy / barium swallow: for hiatal hernia

Management

Watchful Waiting

Surgery

• Tissue repair (e.g., Shouldice, Bassini): primary suture repair of the defect; higher recurrence than mesh
• Mesh repair (e.g., Lichtenstein): tension-free; gold standard for most adult inguinal hernias; significantly lower recurrence rates
• Laparoscopic approaches:
  • TAPP (Transabdominal Preperitoneal): mesh placed in preperitoneal space via peritoneal flap
  • TEP (Totally Extraperitoneal): mesh placed without entering peritoneal cavity

• Quick resuscitation, IV antibiotics, urgent OR
• Assess bowel viability; resect if non-viable
• Mesh use is controversial in contaminated fields — open tissue repair is preferred initially; mesh repair reserved for subsequent elective repair if needed. — Mulholland & Greenfield's Surgery

Pediatric Considerations

Key Associations to Remember

Hernia Surgical Repair: Mesh vs. Tissue Techniques

Background & Historical Context

1. Pre-Bassini era — high mortality/morbidity; crude technique
2. Tissue repair era (1880s–1980s) — Bassini (1884) transformed outcomes; subsequently refined into Shouldice and McVay repairs
3. Tension-free mesh era (1989–present) — Lichtenstein's polypropylene mesh patch became the paradigm shift; laparoscopic approaches (TAPP, TEP) followed in the 1990s

"The popularization of tension-free prosthetic mesh repairs signified a paradigm shift in the surgical concept of inguinal hernia pathophysiology." — Schwartz's Principles of Surgery 11e

PART 1 — TISSUE (PURE) REPAIRS

1. Bassini Repair (Historic — Limited Modern Use)

1. Incise transversalis fascia from pubic tubercle to internal ring
2. Bluntly dissect preperitoneal fat from posterior transversalis fascia
3. Triple-layer suture: internal oblique + transversus abdominis + transversalis fascia fixed together to the shelving edge of the inguinal ligament with interrupted sutures
4. Lateral repair narrows and reinforces the medial border of the internal ring

2. Shouldice Repair (Gold Standard Tissue Repair)

(Lichtenstein repair shown above for comparison — see below)

1. Isolate and mobilize the spermatic cord; divide the genital branch of the genitofemoral nerve (causes ipsilateral scrotal numbness)
2. Incise transversalis fascia from pubic tubercle to internal ring; develop upper and lower fascial flaps
3. Suture 1 (Layer 1): Iliopubic tract sutured to lateral edge of rectus sheath at pubic tubercle; continuous suture runs laterally, approximating the inferior transversalis flap to the posterior surface of the superior flap → reaches internal ring
4. Suture 1 (Layer 2 — return pass): Same suture turns back medially, approximating superior transversalis flap edge to shelving edge of inguinal ligament → tied at pubic tubercle
5. Suture 2 (Layer 3): Begins at internal ring, runs medially apposing internal oblique and transversus aponeuroses to the external oblique aponeurosis
6. Suture 2 (Layer 4): Returns laterally through same structures, tied at internal ring

• In experienced hands at specialized centres: recurrence ~1%
• Significant learning curve: recurrence drops from 9.4% → 2.5% after just 6 repetitions
• Meta-analysis (Cochrane 2012): recurrence OR 3.65 (95% CI 1.79–7.47) higher than Lichtenstein mesh — but much better than other tissue repairs
• Chronic pain, SSI, and seroma rates comparable to Lichtenstein
• Requires longer operative time and hospital stay

3. McVay (Cooper's Ligament) Repair

• Femoral hernia repair (only tissue repair that addresses the femoral defect)
• When prosthetic mesh is contraindicated

4. Desarda Repair (Modern Tension-Free Tissue Repair)

PART 2 — PROSTHETIC MESH REPAIRS (OPEN)

5. Lichtenstein Tension-Free Repair (Global Gold Standard)

1. Incision: 6–8 cm oblique cut inferior/medial to ASIS, extending to just lateral to symphysis pubis
2. Dissection: External oblique aponeurosis opened; ilioinguinal and iliohypogastric nerves identified and preserved; cord isolated on Penrose drain
3. Hernia sac: Separated from cord; high ligation of indirect sac; direct sac reduced
4. Mesh preparation: "Flat iron" shaped; keyhole cut in the distal lateral edge to accommodate the spermatic cord
5. Mesh fixation:
   • Medial edge: overlaps pubic tubercle by ≥2 cm (avoids direct suture into periosteum — reduces osteitis/chronic pain)
   • Inferior edge: running or interrupted suture to shelving edge of inguinal ligament, medial → lateral, ending past the internal ring
   • Superior edge: interrupted absorbable sutures to internal oblique/conjoined tendon
   • Lateral tails: wrapped around spermatic cord to fashion a new internal ring (snug but not constricting)
6. Nerve care: Ilioinguinal and genital branch of genitofemoral nerve are either placed with cord structures or excluded from the repair to prevent entrapment

• Recurrence rate in a 3,019-patient series: 0.2%
• Mesh repair vs. tissue repair: OR for recurrence = 0.37 (95% CI 0.26–0.51) — dramatically lower
• Shorter hospital stay, faster return to activities vs. tissue repairs
• European Hernia Society guidelines: preferred open technique for unilateral and bilateral inguinal hernias

6. Plug and Patch Technique (Rutkow-Robbins / Gilbert)

• Indirect hernia: Plug placed alongside cord through the internal ring, sutured to ring margins
• Direct hernia: Sac reduced; plug sutured to Cooper's ligament, inguinal ligament, and surrounding tissue; onlay patch placed over the floor

7. Rives-Stoppa (Preperitoneal Giant Prosthetic Reinforcement)

PART 3 — MINIMALLY INVASIVE (LAPAROSCOPIC / ROBOTIC) MESH REPAIRS

8. TAPP — Transabdominal Preperitoneal Repair

1. Camera port at umbilicus (≥15 cm from pubis); two lateral 5-mm working ports
2. Peritoneal flap raised 4–6 cm superior to hernia defect, incised to ASIS
3. Dissection to achieve critical view of myopectineal orifice: identify direct space, indirect space, femoral space; Cooper's ligament; inferior epigastric vessels
4. Parietalization of the spermatic cord (cord structures separated from peritoneum)
5. Mesh (≥10×15 cm) placed to cover all three spaces; tacked to Cooper's ligament and abdominal wall (avoiding the "triangle of doom" — external iliac vessels — and "triangle of pain" — lateral cutaneous and genitofemoral nerves)
6. Peritoneal flap closed to exclude mesh from peritoneal cavity → prevents adhesions and visceral injury

9. TEP — Totally Extraperitoneal Repair

1. 1–2 cm infraumbilical incision; anterior rectus sheath incised; muscle fibres spread to reveal posterior rectus sheath
2. Preperitoneal space developed from umbilicus to pubic tubercle using balloon-mediated dissection (or blunt dissection)
3. Hasson cannula inserted; two additional 5-mm midline ports placed inferiorly
4. Dissection to critical view of myopectineal orifice; cord parietalized
5. Mesh placed; preperitoneal space deflated under direct vision to confirm stable mesh positioning (no peritoneal flap closure needed)

10. Robotic-Assisted Repair (rTAPP / rTEP)

Comparative Outcomes: Evidence Summary

Choosing the Right Approach: Decision Framework

Is the field contaminated / bowel strangulated?
  YES → Tissue repair (Shouldice or McVay); delay mesh
  NO  ↓

Is this a femoral hernia with no mesh option?
  YES → McVay repair (only tissue repair closing femoral ring)
  NO  ↓

Open or laparoscopic?
  Bilateral hernias → Laparoscopic (TAPP or TEP) strongly preferred
  Recurrent hernia (prior anterior repair) → TEP/TAPP (uses different plane)
  Recurrent hernia (prior posterior repair) → Open Lichtenstein (anterior)
  Surgeon inexperienced in laparoscopy → Open Lichtenstein
  Patient preference / fit for GA → Guide choice accordingly
  
Open approach → Lichtenstein (preferred) or Plug & Patch
Laparoscopic → TAPP or TEP (equivalent outcomes; surgeon preference)

Complications to Know

• Bassini — historic 3-layer; largely abandoned
• Shouldice — 4-layer running suture; best tissue repair; ~1% recurrence in expert hands; but 3.65× higher recurrence than mesh
• McVay — uses Cooper's ligament; uniquely repairs femoral defects; requires relaxing incision
• Desarda — autologous external oblique patch; good for mesh-free scenarios

• Lichtenstein — global gold standard; 0.2% recurrence; short learning curve; EHS-recommended
• Plug & Patch — 3D plug + flat mesh; equivalent outcomes to Lichtenstein but ~6% plug migration risk limits its use
• Rives-Stoppa — giant preperitoneal mesh; best for recurrent/bilateral/large defects

• TAPP — enters peritoneum; easier to learn; can inspect contralateral side
• TEP — stays extraperitoneal; lower visceral injury risk; steeper learning curve (~100 cases)
• eTEP / Robotic — emerging; expanding operative space; equivalent outcomes