Abstract: Objective   To explore the adjacent relationship between pyramidalis muscle and anterior pubic ligament, so as to provide anatomical basis for further understanding the mechanism of maintaining the stability of the pubic symphysis.   Methods   Twenty-four specimens (19 males and 5 females) were selected to observe the length, width, thickness of the pyramidalis muscle and the adjacent relationship between the adjacent rectus abdominis, adductor longus and anterior pubic ligaments.   Results   In the 24 gross specimens, 23 cases of pyramidalis muscle existed bilaterally (accounting for 95.8%, 19 cases in males, 4 cases in females). One case lacked the right muscle (accounting for 4.2%, 1 case in female). The length of pyramidalis muscle was (70.64±13.48) mm in males and (71.81±11.27) mm in females on the right side, (69.60±12.01) mm in males, (64.25±19.79) mm in females on the left side. Width, on the right side: male (20.68±4.12) mm, female (20.65±2.04) mm, on the left side: male (20.02±2.99) mm, female (18.23±4.77) mm. Thickness, right: male (2.50±1.61) mm, female (1.49±0.40) mm, left: male (2.19±1.06) mm, female (1.50±0.56) mm.   There was no statistical difference in the length, width and thickness of the pyramidalis muscle (P>0.05). The width of anterior pubic ligament was (5.96±1.55)mm in males and (6.60±1.10) mm in the females on the right side, (6.35±1.58) mm in males and (6.16±0.69) mm in females on the left side. The pyramidalis muscle originated from the fibrous ligament anterior to the pubic bone and pubic symphysis with tendinous fibers. The origin of rectus abdominis tendon, adductor longus tendon, inguinal ligament and the starting point of the pyramidal muscle were intertwined with adjacent to the pubic crest, forming a distinct anterior pubic ligament.  Conclusions    The pyramidalis muscle originates from the anterior pubic ligament and forms the anterior pubic ligament together with the inguinal ligament and the adductor longus tendon. At the same time, with the anterior pubic ligament as the center, adjacent structures together form a complex, which provides important support for the stability of the pubic symphysis.

Key words: Pyramidalis muscle,  ,  , Anterior pubic ligament ,  , Anatomy