Background Information: Inguinal hernias occur when abdominal contents or preperitoneal fat herniate through the inguinal canal (indirect) or Hesselbach's triangle (direct). Direct inguinal hernias occur secondary to increased intraabdominal pressure and indirect hernias are a congenital defect related to a patent processus vaginalis (an extension of the peritoneum that closes during normal development). Inguinal hernias are repaired using open or minimally invasive (laparoscopic/robotic) techniques. The minimally invasive repair is achieved through two different approaches: the transabdominal preperitoneal (TAPP) approach, and the totally extraperitoneal (TEP) approach. The proposed advantages of the minimally invasive approach are the use of larger mesh to cover the entire myopectineal orifice, and the ability to easily treat bilateral hernias and recurrent hernias that have been treated with an open technique. The TAPP approach may be performed robotically and can provide additional dexterity and three-dimensional optics to aid in the procedure.

Indications:

Symptomatic direct or indirect inguinal hernia. Within ten years, up to 70% of asymptomatic inguinal hernias will become symptomatic. Minimally invasive repairs are indicated if bilateral hernias are present, if a hernia has recurred following the open approach, or for surgeon preference.

Procedure Description:

TAPP Inguinal Hernia Repair

Three port sites are placed, one at the umbilicus (camera), and two lateral to the rectus sheath at the level of the umbilicus. The trocars are advanced into the peritoneal cavity and pneumoperitoneum is established. Next, the parietal peritoneum is incised and a plane is created within the preperitoneal plane and dissection is continued down to Cooper’s ligament and the iliopubic tract. The hernia sac is then reduced. If an indirect hernia is present, the hernia sac is reduced and dissected from the cord structures (or round ligament in women). Once the dissection of the preperitoneal plane is complete, mesh (14x12cm) is placed in the preperitoneal plane covering the entire myopectineal orifice. The mesh is then sutured or tacked to the abdominal wall. The peritoneum is then sutured to correct the defect.

TEP Inguinal Hernia Repair

Three port sites are placed, one at the umbilicus (camera), and two extending caudally in the midline. Prior to trocars being placed, at the infraumbilical location, dissection is carried down to the posterior rectus sheath. A balloon is introduced into retrorectus space between the posterior rectus sheath and the rectus muscle. As this plane is dissected, caudal to the arcuate line, this space becomes the preperitoneal space. Balloon dissection continues to the pubic symphysis. The remaining procedure proceeds similar to the TAPP procedure.

Key Anatomy:

Subcutaneous tissue

• Camper's fascia
• Scarpa's fascia

Abdominal wall:

• Rectus abdominis
• Anterior rectus sheath
• Posterior rectus sheath
• Arcuate line
• External oblique aponeurosis
• Internal oblique muscle
• Hesselbach's triangle (direct hernia space)

• Lateral border: inferior epigastric vessels
• Inferior border: inguinal ligament
• Medial border: lateral border of rectus abdominis muscle

• Adeniculum of rectus abdominis
• Myopectineal orifice
• Median umbilical ligament

• Contains obliterated urachus

• Medial umbilical ligaments

• Contains obliterated umbilical arteries

• Lateral umbilical folds

• Contains inferior epigastric vessels

Inguinal anatomy

• Iliopubic tract
• Deep (internal) inguinal ring
• Vas deferens
• Cooper's ligament
• Lacunar ligament

Nerves

• Ilioinguinal nerve
• Genital branch of the genitofemoral nerve
• Iliohypogastric nerve
• Lateral femoral cutaneous nerve

Vascular

• External iliac artery/vein
• Inferior epigastric artery
• Corona mortis
• Testicular artery

Bony landmarks

• Anterior superior iliac spine (ASIS)
• Pubic tubercle

Risks:

General surgical risks:

• Bleeding
• Infection

Risks with laparoscopic/robotic repair

• Hernia recurrence (varies widely based on study, up to 10%1)
• Port site hernia (0.5%2)
• Persistent pain (18% vs 25% for open3)
• Mesh infections (rare)

‍

‍

Additional Resources:

ACS/ASC Medical Student Core Curriculum

• https://www.facs.org/-/media/files/education/core-curriculum/abdominal_wall_groin.ashx

Text:

• Sabiston Textbook of Surgery: The Biological Basis of Modern Surgical Practice by Courtney M. Townsend Jr. JR. MD
• Zollinger's Atlas of Surgical Operations, Tenth Edition 10th Edition

by Robert Zollinger, E. Ellison

• Atlas of General Surgical Techniques: Townsend, Evers
• Essentials of General Surgery 5th Edition, by Peter F. Lawrence MD, Richard M. Bell MD, Merril T. Dayton MD, James C. Hebert MD FACS

Key Literature:

• Open vs Laparoscopic approach

• https://www.nejm.org/doi/full/10.1056/nejmoa040093

• Choice of procedure for repairing inguinal hernia recurrence

• https://journals.lww.com/annalsofsurgery/Abstract/2008/04000/Re_recurrence_After_Operation_for_Recurrent.20.aspx

• TAPP vs TEP

• https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD004703.pub2/full

‍

References: 

1. Nienhuijs S, Staal E, Strobbe L, Rosman C, Groenewoud H, Bleichrodt R. Chronic pain after mesh repair of inguinal hernia: a systematic review. Am J Surg. 2007;194(3):394-400. doi:10.1016/j.amjsurg.2007.02.012
2. Swank, H. A., Mulder, I. M., La Chapelle, C. F., Reitsma, J. B., Lange, J. F., & Bemelman, W. A. (2012). Systematic review of trocar-site hernia. British Journal of Surgery, 99(3), 315–323. https://doi.org/10.1002/BJS.7836
3. Grant, A. M., McCormack, K., Ross, S., Scott, N., & Vale, L. (2002). Repair of Groin Hernia With Synthetic Mesh: Meta-Analysis of Randomized Controlled Trials. Annals of Surgery, 235(3), 322. https://doi.org/10.1097/00000658-200203000-00003‍

‍

Read more GIBLIB Virtual Medical Student Clerkship Program courses here.