pubis

The pubis is one of the three fused components of each hip bone (the others being the ilium and ischium) and forms the anterior portion of the pelvic girdle. On each side, the pubis consists of a body (pars symphyseos) and two rami: a superior pubic ramus and an inferior pubic ramus. The pubic body bears the pubic crest and the pubic tubercle, a prominent forward-facing projection that serves as an attachment site for the inguinal ligament.

The superior pubic ramus extends upward and inward to contribute to the anterior column of the pelvic ring and to the acetabulum’s rim, helping to form the boundary of the pelvic inlet. The inferior pubic ramus runs downward and laterally to join the ischium, completing part of the obturator foramen and contributing to the anterior floor of the pelvis.

The two pubic bones are joined at the pubic symphysis, a fibrocartilaginous joint with a surrounding interpubic disc. This joint provides limited motion to absorb impact while maintaining stability of the anterior pelvis. The pubic bones, together with the ilium and ischium, contribute to the acetabulum, the socket for the femoral head, and to the boundaries of the obturator canal.

Clinically relevant landmarks include the pubic crest, pubic tubercle, and the subpubic angle (arch) beneath the symphysis. The subpubic angle is typically wider in females than in males, reflecting sexual dimorphism in pelvic anatomy. Developmentally, the pubic bone ossifies from a body and adjacent superior and inferior ramus centers that fuse in adolescence.