Laparoscopic Inguinal Hernia Repair

Laparoscopic inguinal hernia repair originated in the early 1990s as laparoscopy gained a foothold in general surgery. ^{[1, 2, 3, 4, 5]} Inguinal hernias account for 75% of all abdominal wall hernias, and with a lifetime risk of 27% in men and 3% in women. Repair of these hernias is one of the most commonly performed surgical procedures in the world. ^[6] In the United States, approximately 800,000 inguinal herniorrhaphies are performed annually. ^[7]

Although open, mesh-based, tension-free repair remains the criterion standard, laparoscopic herniorrhaphy, in the hands of adequately trained surgeons, produces excellent results comparable to those of open repair. ^{[8, 9]} In a comparison between open repair and laparoscopic repair, Eklund et al found that 5 years after operation, 1.9% of patients who had undergone laparoscopic repair continued to report moderate or severe pain, compared with 3.5% of those who had undergone open repair. ^[10]

A number of studies have shown laparoscopic repair of inguinal hernias to have advantages over conventional repair, including the following ^{[11, 12, 13, 14, 15]} :

• Reduced postoperative pain
• Diminished requirement for narcotics
• Earlier return to work

Laparoscopic repair has some disadvantages as well, including the following:

• Increased cost
• Lengthier operation
• Steeper learning curve
• Higher recurrence and complication rates early in a surgeon’s experience

The term laparoscopic inguinal herniorrhaphy can refer to any of the following three techniques:

• Totally extraperitoneal (TEP) repair
• Transabdominal preperitoneal (TAPP) repair
• Intraperitoneal onlay mesh (IPOM) repair ^{[16, 17, 18, 19]}

The IPOM repair has largely fallen from favor, and currently, the most commonly performed laparoscopic techniques are the TEP and TAPP repairs. ^{[14, 15, 8]} Although many facets of laparoscopic inguinal hernia repair continue to be debated—such as the possible superiority of one laparoscopic approach to another, comparisons between laparoscopic and open surgery, the learning curve and training issues, and the socioeconomic implications—both TAPP and TEP have been shown to be acceptable and safe for repair of inguinal hernias.

For information on manual reduction of hernias, see Hernia Reduction. For a discussion of open repair, see Open Inguinal Hernia Repair.

Although robot-assisted laparoscopic inguinal hernia repair is becoming popular, it is not yet widely available and is not extensively performed by surgical residents. A scoping review on the involvement of surgical specialists and surgical residents (nonspecialists) in robot-assisted groin hernia repair was carried out by Hansen et al. ^[20] According to this report, the hernia repair was performed by a surgical specialist in 85% of the 67 studies included, and the procedure was attended by a resident in only 13% of the studies. The authors suggested that this technique was being underutilized in the education of surgical residents.

The general indications for laparoscopic inguinal hernia repair as opposed to watchful waiting are the same as those for open inguinal hernia repair.

Classically, the existence of an inguinal hernia has been considered sufficient reason for operative intervention. However, studies have shown that the presence of a reducible hernia is not, in itself, an indication for surgery and that the risk of incarceration is less than 1%. ^[21]

Symptomatic patients (with pain or discomfort) should undergo repair; however, as many as one third of patients with inguinal hernias are asymptomatic. ^[21] The issue of observation versus surgical intervention in this asymptomatic or minimally symptomatic population was addressed in two randomized clinical trials, both of which found that there were no significant differences in hernia-related symptoms after long-term follow-up and that watchful waiting did not increase the complication rate. ^{[22, 23]}

In one study, the substantial patient crossover from the observation group to the surgery arm led the authors to conclude that observation may delay but not prevent surgery. ^[21] This reasoning holds particularly true for younger patients. Thus, even an asymptomatic patient, if medically fit, should be offered surgical repair. In another study, the authors determined that most patients with a painless inguinal hernia will develop symptoms over time and that surgery is therefore recommended for medically fit patients. ^[24]

Some reports have listed specific indications for laparoscopy over open repair, including recurrent hernias, bilateral hernias, and the need for earlier return to full activities. ^{[25, 26, 27, 13, 28, 29, 30]}

Several studies have demonstrated salutary outcomes for laparoscopic repair of recurrent hernias. ^{[26, 31, 32, 25]} Re-recurrence rates may decline to 5% or lower with laparoscopic repair, ^{[26, 33, 34]} compared with rates as high as 20% for anterior repair. ^[35]

The reduced pain after laparoscopic inguinal hernia repair as compared with conventional anterior repair makes laparoscopy the approach of choice for bilateral hernias. ^{[36, 37, 38]} A particular advantage of TAPP repair in a patient with bilateral inguinal hernias is that both sides can be repaired via the same laparoscopic port sites.

The choice of repair for primary unilateral inguinal hernias is controversial. A large Veterans Affairs cooperative study reported a 10% recurrence rate for laparoscopic inguinal hernia repair, compared with a 5% rate for anterior repair ^[9] ; however, multiple authors identified flaws with this study. ^{[39, 40]} Other studies from experienced hernia surgeons have reported recurrence rates for laparoscopic repair that range from 1% to 3%. ^{[41, 42, 43]}

Although the actual hospital costs of laparoscopic repairs are higher than those of open repairs, the increased cost may be offset by the societal benefits of earlier return to full activities. ^{[8, 44]}

Patient preference plays perhaps the greatest role in the choice of one type of repair over another; however, surgical expertise plays a key part as well. Data show that the recurrence rate drops significantly as surgeons gain experience with the laparoscopic technique. Some studies suggest that the learning curve for TEP laparoscopic herniorrhaphy may be as high as 250 cases (as opposed to 25 for open repair). ^[9] TAPP repair has a learning curve closer to that of the open technique. ^[45]

In a prospective randomized study (N = 174) by Shah et al that compared laparoscopic TEP inguinal hernia repair with open Lichtenstein tension-free mesh repair (LMR), postoperative pain and chronic pain were found to be greater in the LMR group. ^[46] The mean operating time was longer in the TEP group, but both the postoperative hospital stay and the time to resumption of normal activities were significantly shorter. There were no major complications in either group.

A Cochrane database meta-analysis comparing TEP with TAPP found no significant difference in recurrence rates but did find that TAPP was associated with a higher risk of intra-abdominal injury. The authors concluded that further randomized controlled trials are needed for definitive comparison of these two techniques. ^[47]

Conclusions about inguinal hernias in female patients are difficult to draw because most of the literature involves male patients. Koch et al found that recurrence rates were higher in women and that recurrence was 10 times more likely to be femoral in women than in men. ^[48] This has led some to conclude that approaches that cover the femoral space (eg, laparoscopic repair) at the time of initial operation are better suited for primary repair in women. ^[49] Further studies will be needed to resolve this question.

The IPOM technique has fallen out of favor because of reports of unacceptably high rates of organ injury, nerve injury, and hernia recurrence. ^[27]

General contraindications for laparoscopic herniorrhaphy parallel those of open repair.

Inguinal hernia repair itself has no absolute contraindications. Just as in any other elective surgical procedure, the patient must be medically optimized. Any medical issues, whether acute (eg, upper respiratory tract or skin infection) or exacerbations of underlying medical conditions (eg, poorly controlled diabetes mellitus), should be fully addressed and the surgery delayed accordingly.

Patients with elevated American Society of Anesthesiologists (ASA) scores and high operative risk should undergo a full preoperative workup and determination of the risk-to-benefit ratio.

Relative contraindications specific to the laparoscopic approach include a lower midline incision, previous preperitoneal surgery (eg, prostatectomy), irreducible hernia, and inability to tolerate general anesthesia.

TEP repair

To undergo TEP repair, patients must be able to tolerate general anesthesia. Although TEP repair has been performed with regional anesthesia, ^{[50, 51]} it is most commonly performed with general anesthesia, and transition from regional to general anesthesia might be required. Patients whose comorbidities preclude general anesthesia should undergo anterior repair under a local or regional anesthetic.

Previous operations in the preperitoneal space (eg, retropubic prostatectomy and TEP) can make TEP repair difficult. TEP is usually facilitated by using space-creating balloons, which generally function poorly when dense adhesions are present in the space of Retzius. Holes in the peritoneum are common in reoperative preperitoneal surgery. A better choice for laparoscopic repair in patients who have previously undergone a preperitoneal operation is TAPP; an anterior repair through an unadulterated plane may be an even better option.

Some surgeons consider previous open appendectomy a relative contraindication for TEP repair in patients with right inguinal hernias. ^[29] On occasion, the appendectomy scar complicates the lateral dissection, but this does not preclude a safe and effective TEP repair.

Previous low midline incisions can also make TEP repair more difficult, though not impossible. Access to the preperitoneal space might have to be moved to a more lateral location rather than the standard location in the midline. Once access is achieved, TEP repair usually proceeds as normal in patients with previous low laparotomies, though some studies report a higher rate of visceral injury in these cases.

TAPP repair

Absolute contraindications for TAPP repair are few. In general, the inability to tolerate general anesthesia is considered an absolute contraindication, though there are reports of spinal anesthesia being used for this procedure. ^{[52, 53]} Other absolute contraindications are coagulopathy (because bleeding in the preperitoneal space can be difficult to assess and control postoperatively) and intra-abdominal infections that limit the use of prosthetic meshes.

Relative contraindications include previous abdominal surgery, especially pelvic surgery, and depend on the type and degree of expected adhesions, the surgeon’s level of comfort with adhesiolysis, and the nature of the hernia.

Previous prostate surgery was once thought to be an absolute contraindication, in that it would necessarily have disrupted the preperitoneal space. With improvement in techniques and familiarity with the TAPP procedure, previous prostate surgery is now considered a relative contraindication, and TAPP has been shown to be safe in this setting. ^[54] However, surgeons should be aware that TAPP repairs in patients who have undergone prostatectomy are more difficult and carry a higher morbidity.

Large inguinoscrotal hernias, though not a contraindication, can be challenging to manage because reducing these indirect sacs laparoscopically can be difficult. Patients with such hernias, especially when being operated on by an inexperienced surgeon, may be better served by an open approach.

It is important for surgeons to weigh the risks and benefits of TAPP repair against those of open repair. Thorough knowledge of the proposed benefits, indications, and contraindications of TAPP repair as compared with TEP and open repairs is essential and will help the surgeon tailor the surgical approach to the individual patient and the particular clinical scenario.

Anatomic considerations

Poor familiarity with the complex anatomy of the posterior inguinal view is an important contributor to the steepness of the learning curve for laparoscopic inguinal herniorrhaphy. ^{[55, 56, 57]} Although the following discussion describes the anatomy from a laparoscopic point of view, a working knowledge of the inguinal region and the anterior abdominal wall remains paramount. For a detailed description of the region, see Open Hernia Inguinal Repair.

The preperitoneal space is contained between the transversalis fascia and the parietal peritoneum. It contains areolar and adipose tissue and the inferior epigastric artery and vein.

Transabdominal laparoscopic landmarks useful in performing the TAPP repair are the obliterated fetal remnants, which divide the posterior surface of the anterior abdominal wall into three fossae as follows ^[58] :

• The median umbilical ligament is a remnant of the embryonic urachus; it forms the center divide by arising in the midline from the apex of the bladder toward the umbilicus
• Laterally, the paired medial umbilical ligaments, vestiges of the fetal umbilical arteries, arise from the superior vesicle arteries toward the umbilicus
• Between the median and medial ligaments lie the supravesical fossae, where external supravesical hernias occur
• Most lateral are the paired lateral umbilical ligaments, which contain the inferior epigastric arteries; between them and the medial ligaments lies the medial fossa, which contains the Hesselbach triangle (the zone of direct hernias), and lateral to the inferior epigastric arteries is the lateral fossa (the site of indirect hernias); thus, the lateral umbilical ligaments separate the lateral and medial fossae and differentiate indirect from direct hernias

There are three key anatomic landmarks in the preperitoneal space that are constant in their presence and location (see the image below). They are a good starting point for getting one’s bearings in this difficult region and may also be helpful in cases of large hernias or recurrences. These landmarks are as follows:

• Inferior epigastric vessels
• Cooper ligament
• Iliopubic tract

The inferior epigastric artery-vein complex lies on the rectus muscles bilaterally. Medial to these vessels but above the iliopubic tract is the external ring, which is not visible in patients without a direct hernia. The internal ring is lateral to the inferior epigastric vessels but is often obscured by them, even when a hernia is present. Its location can be approximated by locating the junction of these vessels and the cord structures. The femoral ring is inferior and lateral to the external ring and lies below the iliopubic tract just medial to the external iliac vessels.

The Cooper ligament is the name given to the periosteum of the superior pubic ramus. The pubic ramus can be easily palpated with a blunt grasper and is an excellent starting point for dissection.

Also deserving of careful recognition is the iliopubic tract (commonly referred to as the shelving edge of the inguinal ligament in open surgery). This aponeurotic stretch of tissue is located posterior to the inguinal ligament and extends from the anterior superior iliac spine to the superior pubic ramus. As a continuation of the transversus abdominis aponeurosis and fascia at the upper border of the femoral sheath, it passes medially to form the inferior border of the internal inguinal ring, crossing over the femoral vessels. ^{[58, 59, 60]}

The surgeon must be aware that the iliopubic tract forms the superolateral border of the so-called triangle of pain, an area bounded medially by the spermatic vessels (see the image below). In this area, tacking of the mesh is to be avoided because of the risk of injury to the femoral branch of the genitofemoral nerve or the lateral femoral cutaneous nerve. ^{[55, 58, 59, 47]}

Another anatomic zone of which the surgeon must be aware is the so-called triangle of doom, which is bordered medially by the ductus deferens and laterally by the spermatic vessels, with its apex at the deep inguinal ring (see the image below). This area contains the external iliac artery and vein; thus, tacking of the mesh must be avoided within its boundaries, and dissection should be limited. ^{[58, 60]}

Other vascular structures should be considered during TEP. There may be a vascular connection between the obturator and external iliac systems, producing a so-called corona mortis. This abnormality is commonly encountered as dissection of the Cooper ligament is taken toward the external iliac vein. Gentle and judicious dissection will limit injury to this structure. Other small veins surround the Cooper ligament and can lead to meddlesome bleeding during TEP.

The surgeon should be mindful of the important nerves in the area as well. The lateral femoral cutaneous nerve travels along the iliopsoas muscle as the nerve courses toward the lateral thigh. The genitofemoral nerve emerges from the psoas muscle medial to the lateral femoral cutaneous nerve. The genital branch of this nerve courses lateral to the spermatic cord and travels through the deep inguinal ring. Both the femoral branch of the genitofemoral nerve and the femoral nerve lie in close proximity to the femoral artery.

Complication prevention

Accurate identification of the laparoscopic anatomy of the groin during laparoscopic inguinal hernia repair helps prevent complications. Careful attention to detail at several points during the surgical procedure can also be helpful. Appropriate positioning and padding can help prevent nerve palsy.

The inferior epigastric vessels may be dislodged by the dissecting balloon used in TEP repair, and this can either cause significant bleeding or impede the dissection. The inferior epigastric vessels can be clipped and divided without consequence. If the bleeding occurs with the vessels in situ, a transabdominal wall suture ligature may be used to control the bleeding. In TAPP repair, starting the peritoneal dissection in the right plane helps prevent injuries to the inferior epigastric vessels during the creation of the peritoneal flap.

Hematoma or seroma formation may occur but is usually self-limited because of the tamponade effect of the peritoneum. On rare occasions, surgical intervention may be necessary.

Small holes in the peritoneum can lead to encroachment of the peritoneum into the working space. This can be remedied in multiple ways, such as by enlarging the hole to equilibrate the intra-abdominal pressure with the preperitoneal pressure, by placing a Veress needle into the abdomen to evacuate the intra-abdominal gas, or by closing the hole securely to prevent passage of carbon dioxide into the peritoneal cavity.

All holes in the peritoneum should be repaired. Large holes do not lead to diminished working space but can lead to postoperative complications. Exposed mesh can lead to adhesions to the small bowel and, in rare cases, bowel injury and fistulization. ^{[61, 62, 63]} A peritoneal rent can also serve as a site for bowel to become incarcerated. ^[64] Peritoneal rents may be closed with sutures, clips, or preformed suture ligatures.

It is particularly important to try to avoid tearing of the peritoneal flap during TAPP; this can be difficult, because the peritoneum can be very flimsy. Tearing the peritoneum may not be a significant complication for this repair, but it will add extra time to the procedure and can complicate peritoneal closure and coverage of the mesh. When the peritoneum is torn and cannot be repaired, a barrier-type mesh or one suitable for intra-abdominal placement can be used. However, this is not ideal, because the peritoneum helps hold the mesh in place.

Intra-abdominal injury is uncommon with TEP repair but may occur if the peritoneum is torn and the abdominal cavity entered. Extra care should be taken with wide-neck hernia sacs that contain abdominal organs. A final intraperitoneal evaluation may be helpful at the completion of the case if an injury is suspected. The potential for intra-abdominal injury is one of the drawbacks of TAPP repair; thus, safe laparoscopic access is essential. Surgeons should employ the laparoscopic access techniques with which they feel most comfortable. ^{[65, 66]}

Obviously, cautious hernia reduction and careful identification of the vas deferens and cord structures are crucial for avoiding complications. Large indirect hernia sacs may be difficult to reduce; their chronicity often results in adherence of the sac to the cord. If, after a diligent effort, the sac cannot be reduced, it can be divided. The sac and cord structures should be clearly separated, and the sac should be free of contents. A cold scissors can be used to divide the sac. The proximal sac should be closed with a suture ligature and the distal sac left open.

Adhesion formation is very uncommon with TEP repair but has been reported with large peritoneal rents. Closure of the defect may be warranted and can be performed laparoscopically with endoscopic clips or an endoscopic loop ligature.

Pain (acute postoperative or chronic) is another potential complication. Injury to the nerves during dissection is a common cause of chronic pain. Such injury can be avoided by gentle dissection in the lateral space inferior to the iliopubic tract and lateral to the spermatic vessels. Great care must be exercised in securing the mesh with tacks. Awareness of the groin anatomy will help surgeons fix the mesh without injuring critical nerves. Nerve injury is usually self-limited but may have to be treated with steroid injections or, if persistent, neurectomy.

Ischemic orchitis leading to atrophic testicle or even necrosis is a catastrophic but known complication of inguinal herniorrhaphy. The exact cause of this vascular injury is unclear, but it is thought to be secondary to venous thrombosis rather than arterial injury. Although this complication is rare, a high index of suspicion should be maintained; this, in conjunction with emergency testicular ultrasonography, may help avoid orchiectomy. Symptoms of ischemic orchitis include painful testicular swelling and fever commencing 2-3 days after surgery. ^[67]

A study comparing heavyweight and lightweight meshes for laparoscopic inguinal hernia repair in men found that the use of lightweight mesh for bilateral repair negatively influenced sperm motility. ^[68] A prospective randomized study involving 59 male patients found that at 1-year follow-up, sperm motility had declined from preoperative levels in patients receiving lightweight mesh but had increased slightly in those receiving heavyweight mesh. No differences in quality of life were noted between recipients of different types of mesh. ^[69]

The use of fascia lata in laparoscopic inguinal hernia repair was reported in a 58-year-old man who presented with an incarcerated right inguinal hernia. ^[70] A TAPP repair of the inguinal hernia was performed, and fascia lata was used in the preperitoneal space as an alternative to synthetic mesh. The outcome was favorable.

As with any hernia repair, postoperative complications are possible. Morbidity is usually low after a TAPP procedure, with one large series reporting a rate of 2.9%. ^[71] Seromas represent the most common postoperative complication. These usually resolve spontaneously and rarely warrant further intervention (eg, aspiration).

Recurrence is a concern. A large randomized, controlled trial comparing laparoscopic with open repair found that with adequate training, laparoscopic repair yielded equivalent recurrence rates, reduced postoperative pain, and earlier return to work. ^[25] Recurrence rates after TAPP repair usually range from 1% to 6%; specialized centers performing large numbers of repairs cite rates of less than 1%. ^{[28, 71, 72, 73]}

Small-bowel obstruction is a rare complication after a TAPP hernia repair and most commonly results from holes created in the peritoneal flap during dissection. As a rule, it is easily prevented by repairing these tears or holes and ensuring proper tacking of the peritoneum to the abdominal wall over the mesh, so that there are no potential holes or gaps through which bowel can herniate.

With respect to outcome, TEP appears to have several advantages over TAPP, including the following ^{[3, 74, 75, 76]} :

• Less risk of intraperitoneal injury
• Fewer intra-abdominal adhesions
• No need to close a large peritoneal envelope

Many surgeons find the working space confining when they first perform TEP repairs, but this challenge can be overcome with experience. Mastery of the anatomy of the preperitoneal space and meticulous surgical technique conduce to favorable outcomes after TEP.

A retrospective study (N = 552) by Lau Young et al assessed postoperative morbidity and quality of life (QoL) after  laparoscopic inguinal hernia repair with self-adhesive mesh. ^[77] The hernia recurrence and reoperation rates were 0.2% and 0.5%, respectively. The most common postoperative complication was hematoma (3.1%). Postoperative QoL was excellent with regard to pain and mesh perception.

A randomized controlled trial (N = 491) by Fafaj et al assessed the effectiveness of urinary catheters for preventing postoperative urinary retention (PUR) after laparoscopic hernia repair. ^[78] The intraoperative use of urinary catheters was not found to reduce the risk of PUR in this setting.