Position and morphology of the appendix vermiformis in Sri Lankans

Abstract

INTRODUCTION: The vermiform appendix varies in length and opens into the posteromedial wall of the caecum, 2cm below the ileo caecal valve. While the position of its base is constant in relation to the caecum, the appendix itself may lie in a variety of positions. OBJECTIVE: To describe the morphological characteristics of the appendix among Sri Lankans. METHOD: A prospective study was carried out among 30 patients who underwent laparoscopic appendicectomy in Colombo North Teaching Hospital and 60 dissected cadavers in the departments of Anatomy at Ragama and Sri Jayewardenepura. While the intra-abdominal position of the appendix was assessed in both laparoscopic appendicectomy patients and the dissected cadavers, the other morphological characteristics were assessed only in the cadavers. RESULTS: The mean length of the appendix was 65mm, (range 35 to 110mm). The base of the appendix opened into the posteromedial wall of the caecum in 96.6% (58/60) and into the apex of the caecum in 3.4% (2/60). The mean outer diameter of the appendix was 5.2mm (range3 to 10mm). The position of the appendix was found to be retrocaecal in 24.4% (27/90), pelvic in 6.6% (6/90), and ileal in 51.6% (46/90) comprising 30% (27/90) post-ileal and21.6%(19/90)pre-ileal. The blood supply of the appendix was the inferior division of the ileo caecal artery in 96.6% (58/60) and the posterior caecal artery in 1.6% (1/60). The mean distance between the base of the appendix and the ileocaecal valve was 21.2 mm, varying from 13 mm to 24mm. CONCLUSION: The frequency of the various positions of the appendix in our study population was different to the reported data. The ileal position of the appendix was the most common and the pelvic position the least common.