Full Pelvis Description
[Continued from above] . . . during childbirth as it is capable of stretching to permit delivery. Attached to the pelvis are muscles of the abdominal wall, the buttocks, the lower back, and the insides and backs of the thighs.
Each innominate bone is made up of three fused bones: the ilium, the ischium, and the pubis. Together they form the acetabulum, which is a cup-like depression ball and socket joint. The ilium is the uppermost and largest and consists of a wide, flattened plate with a long curved ridge (called the iliac crest) along its border. The pubis is the smallest pelvic bone. It extends forward from the ischium and around to the pubis symphysis, where it joins to the other pubic bone by a tough, fibrous tissue. These three bones meet to form a cup-shaped cavity that make up the socket of the hip joint.
There are many structural differences between the male and the female pelvis, most of which reflect the role of childbirth in the female. The male pelvis is larger and smaller inside with the pubis symphysis deeper and longer. The female, on the other hand, has a much more delicate, less prominent pelvis that is wider inside and the pubis symphysis shallow and shorter.