Vertebrae can be divided into 5 groups based on their positions in the body. The first 7 are called cervical vertebrae, the next 12 are called thoracic vertebrae, the next 5 are lumbar vertebrae, the next vertebra, a single vertebra formed by fusion of bones, is called the sacral vertebra, and the last vertebra, also the result of fusion is called the coccygeal vertebra also known as the tail bone.