Variation in length, position and blood supply of the vermiform appendix: a cadaveric study among black Tanzanian population

Abstract

The vermiform appendix is a tubular structure attached to the cecum and demonstrates anatomical variation in length, position, and arterial supply. Such variation is relevant to the diagnosis and surgical management of appendicitis because an appendix located outside the usual retrocecal position or supplied by an atypical artery may alter anatomical expectations during clinical examination and appendectomy (Patra et al., 2024). Despite studies from other populations, limited multi-institutional cadaveric evidence describes these variations among Black Tanzanians. This study determined variations in the length, position, and origin of the blood supply of the vermiform appendix among Black Tanzanian cadavers and examined their association with sex. A descriptive cross-sectional cadaveric study was conducted using 99 cadavers selected from a population of 133 cadavers available in five medical universities in Dar es Salaam. Sample size was determined using Yamane's formula at a 5% margin of error and distributed proportionally across the five institutions. Data were collected through systematic dissection, direct measurement of appendix length, classification of anatomical position, and identification of the origin of the appendicular artery. Data were analysed using descriptive statistics, an independent-samples t-test for length, and chi-square analysis for categorical associations, with statistical significance set at p ≤ .05. Appendix length ranged from 2 to 15 cm, with a mean of 7.15 cm among males and 8.24 cm among females; the difference was statistically significant (t (97) = -2.96, p = .004). Retrocecal position was most common (58.6%), and appendix position was significantly associated with sex after rare positions were collapsed for inferential analysis (χ² (1) = 21.41, p < .001). The appendicular artery originated from the ileocolic artery in 70.7% of cases and from the mesenteric artery in 29.3%; this distribution was not significantly associated with sex (χ² (1) = 0.50, p = .478). The findings demonstrate substantial anatomical variation within the studied Black Tanzanian population and provide local cadaveric evidence relevant to anatomical education and surgical awareness