What causes pain in the tailbone?

Tailbone: Most likely bursitis in coccyx joints from prolonged sitting, otherwise arthritis or hemorrhoids or prostate or anal fissure are rare attributes.

See below: The tailbone or "coccyx" is the small trail of bones that connect to the end of your sacrum, and form the end of your spine. A painful tailbone can come from several things. Trauma to the tailbone which might occur with a fall. An abnormally positioned tailbone that is under stress with prolonged siting, and in very rare cases abnormal growths can occur on the tailbone.