Analysis of right-sided ligamentum teres: The novel anatomical findings and classification

Background The true anatomy of right-sided ligamentum teres (RSLT) has not been fully explained for a century. This study aimed to clarify the exact anatomy of RSLT. Methods The computed tomography data of 17 651 surgical patients were observed and 76 patients with RSLT, were classified into the bilateral ligamentum teres (LT) group (type A) and three RSLT groups, (B) bifurcation type, (C) trifurcation type, and (D) independent posterior branch type. Results Type A had double LT that connected to both the right and left sides of the umbilical portion (UP). Types B-D had a P3 + 4 rather than a left UP. Type D was anatomically different from types A-C. Upon comparing types A-C and type D, type D had a significantly smaller volume of segments 3 + 4 (P < .001), and the UP was more often on the left side. The position of the gallbladder fundus in type D was more commonly observed on the right side of the LT compared with that observed in the other types (P = .007). Conclusions The change in the volume of segments 3 + 4 and the extent of the RSLT shift create a false perception that the gallbladder changes the position.