Images in Surgical Radiology: An Unusual Case of Acute Appendicitis Within a Femoral Hernia

Abstract

We present a rare case of acute appendicitis within a femoral hernia, which was diagnosed preoperatively on CT scan.

Introduction

De Garengeot first described the presence of the appendix within a femoral hernia in 1731. It is a rare occurrence found in less than 1% of femoral hernias [1]. Even less common is the occurence of appendicitis within a hernia occur (thought to be the consequence of luminal obstruction) [1, 2].

Case Report

We report an unusual case of a 74-year-old woman who presented with a 2-day history of painful swelling in her right groin. She had borderline pyrexia (37.8°C) and a tachycardia. Clinical examination revealed a tender, irreducible swelling below and lateral to the pubic tubercle with edematous, erythematous overlying skin. CT scan confirmed the clinical diagnosis of an incarcerated femoral hernia; however, it also raised the suspicion of acute appendicitis of an appendix within the hernia (Fig. 1). In theater the CT findings were confirmed. The femoral hernia was approached via a low incision. The sac was opened confirming an appendix with necrotic tip within the hernial sac. The appendix was reduced back into the abdominal cavity. A standard appendicectomy was then performed via a Lanz incision prior to sutured repair of the defect at the femoral canal. The patient made a good recovery and was discharged home on the 4th postoperative day. Histopathology subsequently confirmed transmural appendicitis.

Fig. 1.

Contrast-enhanced CT scan demonstrating an acutely inflamed, edematous appendix, herniating through the femoral canal

To date there are only approximately 60 cases of acute appendicitis within a femoral hernia described in the literature [2]. Preoperative diagnosis is rarely made, and misdiagnosis either as an Amyand’s hernia or a simple incarcerated femoral hernia is conmmon [3]. We highlight this atypical presentation of acute appendicitis and advocate the role of preoperative CT scanning in making the diagnosis.