Inguinal Hernia Repair: Laparoscopic

Surgical Anatomy of the Region

A comprehensive understanding of the anatomy of the preperitoneal space is critical to the performance of a safe and effective laparoscopic inguinal hernia repair. The anterior approach to inguinal hernia repair involves recognition of the anatomy from a superficial to deep position; this is in contrast to laparoscopic repair, which requires identification of the critical structures from a reversed viewpoint.

The median umbilical ligament covers the urachus and travels from the umbilicus to the bladder ( Fig. 53A.1 ). The paired medial umbilical ligaments are remnants of the fetal umbilical arteries. The inferior epigastric vessels originate from the external iliac vessels and have a peritoneal covering creating the paired lateral umbilical folds. These folds originate medial to the deep inguinal ring and travel to the arcuate line, where the inferior epigastric vessels enter the rectus sheath. The medial inguinal fossa is the space located between the medial umbilical ligament and lateral umbilical fold bilaterally. This is the space associated with direct inguinal hernias. The lateral inguinal fossa is the depression lateral to the lateral umbilical fold. Indirect inguinal hernias develop at this site. The pectineal (Cooper) ligament is formed from fascia and periosteum and travels along the pectineal line of the pubic bone. The iliopubic tract is a thickened band of fibers from the transversalis fascia that joins laterally to the iliac crest and inserts medially on the pubic tubercle and pectineal line.

The major vascular structures in this region are generally located medial to the deep inguinal ring. The inferior epigastric vessels branch from the external iliac vessels and travel to supply the anterior abdominal wall. A vascular connection may be noted in some patients between the obturator and external iliac vessels crossing the superior pubic ramus. This is known as the “corona mortis,” or crown of death, as injury due to dissection in this area can lead to significant hemorrhage. There are several other dangerous areas of dissection with laparoscopic hernia repair. The “triangle of doom” is located between the vas deferens medially and the gonadal vessels laterally. The external iliac vessels, deep circumflex iliac vein, genital branch of the genitofemoral nerve, and femoral nerve are located within this triangle.

The key nerves in this area are located lateral to the deep inguinal ring ( Fig. 53A.2 ). In the laparoscopic approach, the following nerves with cutaneous innervation may be encountered from laterally to medially: the lateral femoral cutaneous nerve, the anterior femoral cutaneous nerve, femoral nerve, femoral branch of the genitofemoral nerve, and genital branch of the genitofemoral nerve. The area inferior to the iliopubic tract and lateral to the gonadal vessels is known as the “triangle of pain,” where the lateral femoral cutaneous nerve and femoral branch of the genitofemoral nerve are found. Tacks placed in this area may injure either of these nerves. Together, the area between the vas deferens medially and the iliopubic tract superiorly and laterally constitutes “the square of doom,” where tacks and electrocautery should never be applied to avoid nerve injury.

The previous anatomic discussion is required to understand the landmarks that define the three spaces associated with groin hernias ( Fig. 53A.3 ):

• 1

  Indirect inguinal hernia—lateral to the inferior epigastric vessels.

• 2

  Direct inguinal hernia—medial to the inferior epigastric vessels and lateral to the border of the rectus abdominis muscle within the triangle of Hesselbach.

• 3

  Femoral hernia—below the iliopubic tract, medial to the external iliac vein, and lateral to Cooper ligament.

All three of these spaces should be covered during the laparoscopic approach with an appropriately sized mesh.

Laparoscopic Versus Open Repair

The decision to perform an inguinal hernia repair via a laparoscopic versus an anterior approach remains difficult, complex, and nuanced. Tension-free anterior mesh repair has been the gold standard because of its low recurrence rate and lack of need for specialized equipment. Critiques of the laparoscopic approach include the higher in-hospital costs due to more expensive equipment, the possibility of intraabdominal organ or vascular injury, and the steep learning curve. Studies have indicated that greater than 250 operations are required to become experienced in this technically challenging operation. In fact, a recurrence rate of greater than 10% has been reported for surgeons who have performed fewer than 250 procedures. For this reason, some have argued that the laparoscopic approach should be reserved for experienced centers. Conversely, many trials have shown significantly less early postoperative pain resulting in less narcotic use and swifter return to normal activity.

Nevertheless, most large trials have failed to consistently show a difference in recurrence rates between the two approaches. The biggest exception is a study out of the Veterans Administration (VA) system from 2004. In this study, more than 2000 male patients within the VA system were randomized to an open or laparoscopic inguinal hernia repair with mesh. With 2-year postoperative follow-up, the laparoscopic group had a significantly higher recurrence rate than the anterior approach in the repair of primary hernias (10.1% vs. 4.0%). However, recurrence rates were similar if the repairs of recurrent hernias were compared (10.0% vs. 14.1%). This study has steered many surgeons to repair unilateral primary inguinal hernias through an open approach.

More recent research has attempted to clarify this dilemma. In a meta-analysis of 27 randomized controlled trials of primary unilateral inguinal hernia repair including 7161 patients, O'Reilly et al. found that the laparoscopic approach resulted in an increased risk of recurrence. Interestingly, compared with open repair, TEP had increased rates of recurrence but TAPP had equivalent rates. Additionally, the laparoscopic approach was associated with higher perioperative complication risk. This was attributed to a higher complication risk with TAPP but equivalent risk with TEP. However, laparoscopic repair resulted in reduced risk of chronic groin pain and numbness compared with the anterior approach.

The laparoscopic repair technique may be better suited for bilateral or recurrent inguinal hernias and hernias in women. Bilateral hernias may be repaired through the same set of port sites and do not require additional incisions. In recurrent hernias, especially those with previous open repair, a posterior approach results in dissection through native tissue planes. Some studies have suggested this may lead to improved recurrence compared to redo anterior repair. Inguinal hernias in females may be better performed laparoscopically given that the posterior placement of mesh allows for coverage of the femoral space, therefore addressing the incidence of femoral recurrence seen in Lichtenstein repair. The importance of this concept was illustrated in a series of hernia repairs in women which showed a 41.6% rate of femoral hernia found during operations for recurrences.

Operative Technique

Transabdominal Preperitoneal Repair

The patient is placed in the supine position with both arms tucked. An indwelling catheter is placed in the bladder to prevent view obstruction and decrease the risk of injury to the bladder during dissection of the preperitoneal space. The monitor is placed at the foot of the table. The surgeon stands behind the shoulder opposite to the hernia, and the camera assistant stands on the other side of the patient. Steep Trendelenburg is required to remove the small bowel from the pelvis and adequately visualize the area to be dissected.

Three ports are required for this operation. A 10-mm port for the laparoscope is placed at the umbilicus. Two additional 5-mm ports are placed lateral to the rectus muscle on either side at the junction of a line between the umbilicus and the anterior superior iliac spine ( Fig. 53A.4 ). Alternately, the two 5-mm ports can be placed at the midline between the umbilicus and pubic bone for the TEP repair. A 30-degree laparoscope is required, as the oblique orientation of the inguinal canal makes it difficult to visualize small hernias and it is challenging to open the peritoneum at the anterior abdominal wall without the 30-degree angle.

Following the establishment of pneumoperitoneum—which is maintained at 15 mm Hg—and port introduction, attention is turned to raising the peritoneal flap. If the trocars are inserted too low, it can be very difficult to produce an adequately sized peritoneal flap or easily maneuver the tacking device or the fibrin glue sprayer. On the other hand, if they are placed too high, the small bowel may get in the way. Therefore optimal placement of trocars and a 30-degree laparoscope are essential to success.

The peritoneal flap may be incised from lateral to medial or medial to lateral. If a lateral-to-medial dissection is chosen, the incision begins medially to the anterior superior iliac spine ( Fig. 53A.5 ). This then extends medially, staying at least 2 cm above the deep inguinal ring and hernia defect, and ends at the medial umbilical ligament. Blunt dissection is used to enlarge the peritoneal flap and expose the critical landmarks in the preperitoneal space, including the pubic tubercles, Cooper ligament, and the iliopubic tract ( Fig. 53A.6 ).This dissection of the areolar tissue can be done with minimal hemostasis, and electrocautery is used with care in this area to avoid nerve injury. The femoral nerve is present under the iliopubic tract at the lateral aspect of the dissection, but this nerve is not commonly visualized during this procedure. In thin patients, the lateral femoral cutaneous nerve and the genitofemoral nerve may be identified.

In males, the spermatic cord structures are dissected free of the peritoneal flap. This involves separating the cord structures, including the vas deferens, from the peritoneum and the hernia sac. The peritoneum must be dissected quite inferiorly, as inadequate mobilization can result in folding of the mesh after peritoneal closure and early recurrence. If the view of the operative site is obscured with blood, it can be irrigated and aspirated or cleaned with gauze placed intraabdominally. Direct hernia sacs and small indirect hernia sacs can often be easily reduced during this dissection.

In the case of a very large indirect inguinoscrotal hernia, the distal part of the sac can be divided and left within the scrotum if it cannot be reduced. This dissection begins with gentle and atraumatic separation of the sac from the spermatic cord structures. As the sac is separated, it is divided, but care should always be taken to ensure that the vas deferens is not included with the sac. It may be easier to locate the vas deferens before starting the division of the hernia sac, but often a gradual division of the sac will allow for complete separation of the sac from the cord. Once the peritoneal sac is completely excised, the operation continues as usual. The distal portion of the divided sac is left open in the inguinal canal and the proximal part is ligated using an Endoloop or clips. This method is employed if the complete sac cannot be reduced as significant dissection at the distal sac in larger hernias can cause hematoma formation, ischemic orchitis, or atrophy of the testicle.

When the hernia sac has been completely reduced and dissection of the preperitoneal space is complete, the mesh is rolled and introduced through the umbilical port using a grasper ( Fig. 53A.7 ). Mesh of an appropriate size should be used, typically a 15- by 10-cm piece will be adequate for one side. Once inside the abdominal cavity, the mesh is unrolled and positioned so that it covers the direct, indirect, and femoral spaces. Fixation is then performed with fibrin glue, tacks, or suture. Some surgeons feel that complications of fixation, and associated vascular or nerve entrapment can be avoided if a significantly large piece of mesh is placed. Our technique of choice currently is to use fibrin glue. The fibrin glue is sprayed over the mesh in a thin layer, especially over Cooper ligament and the lateral aspect of the mesh. However, if one chooses to use tacks, the mesh fixation can begin at the midportion, “three fingers” above the superior limit of the internal ring to avoid nerve injury. Nerve injury can lead to severe chronic pain due to neuroma formation around the staple or tack. Then tacks may be placed laterally and medially; laterally, it is essential to stay above the iliopubic tract, but tacks placed medially are inserted into the rectus muscle and on Cooper ligament. Usually two staples or tacks are placed in Cooper ligament and one or two in the rectus muscle. Staples or tacks are often used for fixation in laparoscopic inguinal hernia repair due to the risk of shrinkage or migration of the mesh.

After the mesh is secured, pneumoperitoneum pressure is reduced to 10 mm Hg. The peritoneal flap is then positioned over the mesh and closed with tacks. Absorbable tacks are preferred to prevent subsequent adhesions to the tacks. Complete mesh coverage is essential to prevent exposure of the mesh to the underlying small bowel. This can lead to the creation of adhesions and possible small bowel obstruction. If possible, tacking is performed in an overlap fashion. The peritoneal flap can also be closed using a continuous running suture per surgeon preference. The fascia is routinely sutured at the umbilical port during closure.