What is the protrusion of the tail vertebrae? The caudal vertebrae is the human tail degenerated in the evolutionary process, the bone is still retained, but no tail, so the protrusion of the normal situation is a certain backward. The backwardness is different for each person, some people protrude more obviously, some people protrude less obviously, all belong to the normal, as long as it does not cause pain, or appearance caused by obvious impact, there is generally no special treatment, is a normal phenomenon. When the protrusion is more serious, or by external force caused by local fractures, or even dislocation, generally need to deal with, simple protrusion is a normal phenomenon, does not require special treatment.