The pelvis is a basin-shaped structure that supports the spinal column and protects the abdominal organs. It contains the following:
Sacrum. A spade-shaped bone that is formed by the fusion of 5 originally separate sacral vertebrae.
Coccyx (also called the tail bone). Formed by the fusion of 4 originally separate coccygeal bones.
Ilium. The broad, flaring portion of the hipbone (the crest of the pelvis).
Pubis. The lower, posterior part of the hipbone.
Ischium. One of the bones that helps form the hip.