How many bones are there in the human backbone, including the five that are fused to form the sacrum and the coccyx?
Axial skeleton rib pair number 12. The first rib is the shortest, broadest, flattest, and most curved.<ref name="Human Body Maps/Ribs"></ref> At birth the majority of humans have 33 separate vertebrae. However, during normal development several vertebrae fuse together, leaving a total of 24, in most cases. The confusion about whether or not there are 32-34 vertebrae stems from the fact that the two lowest vertebrae, the sacrum and the coccyx, are single bones made up of several smaller bones which have fused together. This is how the vertebrae are counted: 24 separate vertebrae and the sacrum, formed from 5 fused vertebrae and
Coccyx fracture Coccyx fracture A coccyx fracture is a fracture of the coccyx, commonly called a 'broken tailbone' or ‘puzzle fracture.’ The coccyx is located at the base of the spine, under the sacrum. It is the last section of the ape vertebral column. Most commonly in humans it comprises 3 to 5 fused (or, more rarely, separate) vertebrae, and is approximately 4 to 10 cm in length. The coccyx is attached to the sacrum by a fibrocartilaginous joint, called the sacrococcygeal symphysis, allowing for some (but little) movement. Causes of coccyx fracture can vary greatly, but are most commonly confined to