Reappraisal of the variational anatomy of the vermiform appendix and their possible clinical applicability: a cadaveric analysis.

ABSTRACT

BACKGROUND: The anatomical variations in the position, length, arterial supply and extension of mesoappendix of the vermiform appendix (VA) are pivotal to establishing a standard pattern in the study population of known ethnicity and their clinical applicability. MATERIALS AND METHODS: The present study was conducted on 47 adult human cadavers, thirty-five males and twelve female subjects of North Indian ethnicity. RESULTS: Retrocaecal appendix was found in 23 cases (48.9%) followed by pelvic in 13 (27.7%), three cases each of pre-ileal, post-ileal, and promontoric (6.4%), one case (2.1%) each of paracaecal and subcaecal reported. The length of VA varied from three to ten centimetres, averaging about 7.37±1.67 cm, both the shortest (2.9 cm) (female) and longest (10 cm) (male) were of retrocaecal type. The main appendicular artery (MAA) showed a widely varied branching pattern within the mesoappendix, ranging from three to seven. Fourteen cases (29.78%) showed the accessory appendicular artery (AAA) or dual arterial supply, arising from the ileocolic artery in ten (21%) and in four from the post-caecal (9%). In the specimens with dual arterial supply, the estimated portions of the VA supplied by the MAA also vary with distal ¾th being supplied in 57.14%. In ten cases (21%), the mesoappendix failed to reach the tip of the VF. CONCLUSIONS: Knowledge of anatomical diversities in position, length, course, arterial supply, branching pattern, and mesoappendix is potentially crucial in avoiding surgical catastrophes. Atypical positions of the organ can cause diagnostic confusion and result in delayed treatment. VF supplied by an end artery is one of the causes of the occurrence of appendicitis and mesoappendix not reaching the tip making the organ more vulnerable to necrosis. Vascular variations and anomalies involving the main or accessory appendicular artery are critical to prevent haemorrhage or faulty ligatures.