URMC / Encyclopedia / Content Search Encyclopedia Anatomy of the Male and Female Pelvis 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. Three 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. Medical Reviewers: Rahul Banerjee MD Raymond Turley Jr PA-C Stacey Wojcik MBA BSN RN