Management of appendicitis in a De Garengeot hernia: Lockwood approach

Abstract

A De Garengeot hernia is a femoral hernia containing the vermiform appendix. This extremely rare hernia is associated with appendicitis and the risk of perforation and abscess formation. Given limited data, it poses both diagnostic and management difficulties. While management is generally surgical, questions remain about the best operative approach, indications for appendicectomy and optimum hernia repair technique. We describe a case of acute appendicitis within a De Garengeot hernia that was managed with an open appendicectomy via a Lockwood incision. This case helps to illustrate the management considerations present for this rare clinical pathology and describes a method to effectively identify the hernia and resect the appendix.

Background

Approximately 10% of the population will develop some type of hernia in their life. Of these, femoral hernias comprise approximately 3%–5%.¹ One of the rarest groin hernias was first described in 1731 by French Surgeon De Garengeot.² A De Garengeot hernia refers to the rare occurrence of a femoral hernia containing the appendix and constitutes 0.5%–5% of femoral hernias.³ This differs from its more well-known counterpart—Amyand hernia—which involves the appendix within an inguinal hernia.

Appendicitis within a De Garengeot hernia is a rare presentation for incarcerated hernia. History, examination and blood tests are generally low yield in the diagnosis of this entity. CT scan has some diagnostic utility, with the presence of a blind-ending structure in the hernia without associated evidence of proximal bowel dilatation suggestive of the diagnosis. Thus, the majority of cases are diagnosed intraoperatively on opening the hernial sack.

The pathophysiology of De Garengeot hernias is thought to be due to three potential factors, or a combination of each.⁴ The first is a low-lying caecum due to a form of intestinal malrotation that leaves the appendix in close proximity to the femoral canal. Another risk factor is a long appendix that can project into the femoral canal. Finally, a mobile caecum that can sit adjacent to the femoral canal can result in a De Garengeot hernia. Additional risk factors are similar to those for femoral hernia including female sex, increasing age, obesity and smoking.

Although appendicectomy is advocated in the presence of any macroscopic inflammation, there is ongoing debate regarding appendicectomy for a macroscopically normal appendix within a De Garengeot hernia. It has been suggested that appendicectomy should always be performed as it is impossible to rule out microscopic inflammation and that handling of the appendix may lead to secondary appendicitis.⁵ On the other hand, it has been argued that transection of an appendix containing faecal material may lead to bacterial seeding and corresponding infective complications.⁶ At present, there is a scarcity of data surrounding the use of mesh in De Garengeot hernia repair due to limited numbers of mesh repair being conducted. In a review of 222 patients, 48 received mesh repair with 3 of these suffering mesh infection.⁷

The optimum surgical technique for management of a De Garengeot hernia remains a clinical decision by the surgeon. Guenther et al suggested a laparoscopic approach should be considered in all stable patients without concern for perforation or localised collection. They developed a rating scale based on the appearance of the appendix and suggested operative techniques based on this (figure 1).⁷ In the presence of perforation or abscess, an open approach is advocated as it allows better source control within a femoral hernia compared with a laparoscopic approach. Open approaches are identical to that of femoral hernia repair and include modified McEvedy, Lotheissen transinguinal and Lockwood low incisions. Each of these approaches has its inherent advantages and limitations, and to date no approach has been shown to be superior for management of a De Garengeot hernia.⁸

Figure 1.

Guenther et al’s Classification of De Garengeot hernia.

Case presentation

A female in her 80s presented to ED with a 5-day history of a tender right groin swelling. This had increased in severity over the preceding 24 hours. She described no other abdominal pain with normal bowel motions. She had a history of asthma, hypertension, hyperlipidaemia and a caesarean section via Pfannestiel incision. On examination, there was a 2×2 cm egg-shaped mass in the right groin with overlying mild erythema. It was non-reducible and tender to palpation. Blood tests were normal with a white cell count of 7.5×10⁹/L. A CT scan was conducted that showed a right femoral hernia containing the appendix with adjacent fluid collection around the tip of the appendix and a hernial sac measuring 27×34 mm (figure 2).

Figure 2.

CT scan showing De Garengeot hernia with the inflamed appendix and localised free fluid (white arrow—hernia, blue arrow—appendix).

Treatment

The patient was started given antibiotics and made nil by mouth. She proceeded to the operating theatre the following morning, 6 hours after presentation. A laparoscopic approach was considered in this case initially; however, it was abandoned due to the concern of being unable to reduce the hernia laparoscopically. An open approach with the infrainguinal Lockwood approach was adopted. Following incision, the femoral hernia sac was identified and dissected free of surrounding tissue and opened. An inflamed appendix with perforated tip was found within the sac (figure 3). The base of the appendix appeared healthy and was removed through the same incision with division of appendiceal artery and two Endoloop PDS II to the base. The hernia sac was resected and copious washout was performed. The hernia defect was primarily repaired with non-absorbable sutures.

Figure 3.

Intraoperative findings of a De Garengeot hernia containing inflamed appendix.

Outcome and follow-up

The patient made an uneventful recovery and was discharged on postoperative day 2. Histopathology showed acute appendicitis with focal serositis and intraluminal faecal material. The patient had recovered to preoperative function without complication at 2-month follow-up.

Discussion

Open approaches are similar to those for femoral hernia repair and include the modified McEvedy, Lotheissen and Lockwood approaches. The modified McEvedy approach involves an oblique incision superior to the inguinal ligament and access the preperitoneal plane through an incision in the rectus sheath. This has been shown to be useful in the emergency setting where bowel resection may be required.⁹ The Lotheissen approach uses a transinguinal approach and incision in the external oblique aponeurosis to gain access to the hernia although has limited use due to increased risk of subsequent inguinal hernia. Finally, Lockwood’s approach accesses the femoral hernia sac via an infrainguinal incision. This uses the transversalis fascia for posterior wall repair and is often used in elective hernia repair.

The optimum open approach to management of a De Garengeot hernia is not known due to the rarity of this pathology. Case reports have described the successful use of all three open approaches.^10–12 In our case, despite the emergent setting, we decided to use a Lockwood approach due to its ability to provide good access to the hernial orifice. A common disadvantage of this approach is the limited access to the small and large bowel, requiring a separate incision if a bowel resection is required. If the base of the appendix is unable to be assessed due to inflammation, abscess or tethering, which can prevent externalisation of the pathology, a minimally invasive approach can be attempted by inserting in a laparoscopic camera and working ports. If this does not achieve an adequate view of the base, a limited midline incision would be required. In our situation, the preoperative diagnosis of a de Garengeot hernia established that a bowel resection was unlikely to be required and as such the primary drawback of the Lockwood approach was mitigated. The advantages of the Lockwood approach in this setting are that the direct access to the hernia allowed for rapid assessment and management of the hernia without the need for significant tissue dissection. Utilisation of Endoloop II PDS can potentially overcome the limitation of the Lockwood approach in the setting of appendicectomy. It secures the appendiceal base without requiring significant access to the caecum and appendiceal base.

Learning points.

• A De Garengeot hernia is a femoral hernia containing the vermiform appendix.

• Management is generally surgical with laparoscopic and open approaches having been described.

• Preoperative diagnosis can play an important role in identifying the presence of appendicitis within a De Garengeot hernia as well as an assessment of the risk for needing bowel resection, which can inform operative approach.

• The Lockwood approach can be useful in managing De Garengeot hernias, allowing easy access to the hernia without requiring significant tissue dissection.

• An Endoloop can provide a useful way to retract the appendix and allow assessment of the caecum.

Ethics statements

Patient consent for publication

Consent obtained directly from patient(s)