Illustrated Anatomy of a Rare Variant: Moynihan’s Hump With Independent Anterior and Posterior Cystic Arteries

Anatomical variation within Calot’s triangle can complicate hepatobiliary surgery and increase the risk of vascular injury during laparoscopic cholecystectomy (LC). Among these variations, a tortuous right hepatic artery (RHA), known as Moynihan’s hump, and the presence of dual cystic arteries have each been described individually; however, their concurrent occurrence is rarely documented and sparsely illustrated in the literature. During routine cadaveric dissection at the University of Pikeville - Kentucky College of Osteopathic Medicine (UP-KYCOM), a rare vascular configuration was identified, in which a Moynihan’s hump of the RHA gave rise to two independent cystic arteries supplying the gallbladder. Both branches originated near the Moynihan’s hump and entered Calot’s triangle separately. This report provides high-resolution cadaveric photographs and an original anatomical illustration that clarify the spatial relationships between the tortuous RHA and the dual cystic arteries. The combined visual documentation offers a practical reference for understanding how this variant may obscure normal surgical landmarks and increase the risk of misidentification during cholecystectomy. By presenting clear cadaveric visualization alongside an educational schematic, this case contributes to the limited literature describing the coexistence of Moynihan’s hump with dual cystic arteries and emphasizes the importance of incorporating anatomical variation into surgical training and anatomical education.