An Incidental Discovery of Amyand's Hernia: A Case Study and Literature Review on Its Intraoperative Management

Abstract

Amyand's hernia (AH) is a rare form of an inguinal hernia where the vermiform appendix is found within the hernia sac. Diagnosis is usually based on incidental finding intraoperatively. The AH makes up a small proportion of all inguinal hernia cases, and concurrent acute ischemic complication makes up an even smaller subset. We present an 85-year-old male who was referred to general surgery services for a growing mass on his right lower quadrant in the inguinal region. This was non-tender on palpation, and therefore there was no suspicion of ischaemic complications. An open hernioplasty was performed with resection of the appendix. The AH in this patient would be conventionally classified as type 1 AH, which would be managed with hernial reduction and mesh repair. The anatomical variance in our patient's AH increased the risk for hernial incarceration; hence an appendectomy was also performed despite the absence of acute appendicitis. This approach was also deemed necessary to avoid the recurrence of hernia due to its large size and adhesions within the hernial sac. This study reports a novel management approach for an incidentally discovered type 1 AH. It highlights that there is a lack of management guidance for the AH anatomical variants. The classification and management for AH under the conventional Losanoff and Basson's AH classification model have limitations that can be amended by incorporating the physical dimensions of the AH. This approach will enable surgeons to recognize and manage more variations of AH while mitigating downstream complications.

Keywords: amyand; amyand’s hernia; appendectomy variants; general surgery; hernioplasty.

Figure 1. Hernia sac with an incarcerated appendix (*) outpouching from the deep inguinal ring (blue arrow), which is visible on reflection of Internal oblique (IO) and fascia transversalis (FT). The ilioinguinal nerve (yellow arrow) is secured.

Figure 2. Reflection of the external oblique (EO) and internal oblique (IO) provides inguinal canal exposure. The hernial sac (yellow arrow), the inferior epigastric vessels (green arrow) and the spermatic cord (blue arrow) are seen exit into the superficial inguinal ring. The appendix (*) is seen visibly herniating out of the deep inguinal ring.

Figure 3. Amyand’s hernia wherein the appendix (*) is enclosed within the hernial sac (pink arrow) and physically adheres to it with the fibroelastic tissue (yellow arrow).

Figure 4. A: shows the opened hernial sac contents revealing the caecum (CE) and the appendix (*). B: shows the resected gross specimen of the appendix (*) with no visible localized inflammatory changes.