Anatomical Challenges in Laparoscopic Cholecystectomy: Five Arterial Branches from a Right Hepatic Caterpillar Hump

BACKGROUND Caterpillar hump, also referred to as Moynihan's hump, is a right hepatic artery with tortuous course within the Calot's triangle, which carries a major risk of accidental injury and ligation during laparoscopic cholecystectomy. Its already rare incidence (about 3.81%), in association with the typical presence of 1 or 2 cystic arteries, makes our case unique since it involves a caterpillar hump with 5 distinct arterial branches. CASE REPORT We report a case of caterpillar hump detected during elective laparoscopic cholecystectomy for symptomatic cholelithiasis in a 49-year-old man. A large vessel-like structure with an uncertain termination was initially identified after the hepatocystic triangle dissection. The structure was eventually discovered to have a helical route and re-enter the liver. Although more than 2 elements entered the gallbladder, which exceeded the 'critical view of safety' requirements, a thorough dissection was performed. The surgery is successfully completed when all branches end up in the gallbladder. CONCLUSIONS This report summarizes the clinical and surgical importance of the caterpillar hump, highlighting the necessity for precise anatomical knowledge and the implementation of a "culture of safety" to prevent complications. The concept of "structure" in achieving the "critical view of safety" must encompass its variations and anomalies. Therefore, surgeons must be aware of the potential for multiple arterial branches supplying the gallbladder.