Mesoappendix position variations in laparoscopic appendicectomy; a new anatomical classification to guide surgical strategy.

Dissection of the mesoappendix from the appendix is a crucial step in laparoscopic appendicectomies. Variation in the position of the mesoappendix during this common operation has not been previously described. We propose a classification system for the mesoappendix position seen laparoscopically and evaluate the impact each position has on operative difficulty and surgical approach. The mesoappendix positions in laparoscopic appendicectomies between January 2023 and January 2024 were classified into four categories from M1 to M4. Patients were grouped according to their mesoappendix positions. Outcomes evaluated included operative time, need for additional ports, use of energy devices, deviations from standard operative approach. Various mesoappendix positions were correlated with the intra-operative appendix position and histopathological findings. 104 laparoscopic appendicectomy cases were reviewed. 30 were classified as M1, 31 as M2, 27 as M3, and 16 as M4. Mean operative time was significantly longer for cases where the mesoappendix was in the M3 position (p > 0.001). This position was also more likely to require an additional port and deviate from the standard operative approach including need for retrograde dissection and staple cecectomy. We introduce a potentially surgical important classification system of the mesoappendix in laparoscopic appendicectomies. In this study, we attempt to validate the differences each position has on operative approaches and outcomes. We found that the M3 position is of greater difficulty to approach when dissecting the mesoappendix. This classification may serve as a valuable tool in guiding intra-operative surgical decision-making.