Pelvis

When Elvis "the Pelvis" Presley first displayed his pelvic gyrations to the public, what did everybody think of?

Sex.

And when Michael Jackson or Madonna starts swiveling and thrusting, what can''''t you help thinking about?

Sex.

But the pelvis itself--a ring of bones in the lower trunk--is really designed to bear your weight and protect your internal organs. In women the pelvis is uniquely designed for childbirth. So much for pelvic erotica.

The pelvis, or pelvic girdle, as it is officially called in medical lingo, is located between your belly button and your crotch. When you place your hands on your hips, you are actually resting them on top of your pelvis. The true hip--the hip joint, that is--is located lower down and further inward.

In women the pelvis tends to be wider, lighter, shallower and rounder than it is in men. The center opening is larger and rounder so that the head and body of a fetus can fit through at birth. Also, the joint where the two sides meet is less rigid in women, so that the pelvis can expand during childbirth.

The pelvis is a tough bone, but it can get fractured. In older women, fractures are most often related to osteoporosis. Automobile accidents are another common cause, says Ira H. Kirschenbaum, M.D., arthritis and joint replacement surgeon at Westchester Bone and Joint Associates in White Plains, New York.

See also Skeletal System