Such trauma can bruise the periosteum (connective tissue that surrounds the bone), causing pain.
Whatever the outcome of the trauma, getting pain relief for an injured tail bone can be difficult.
Childbirth is another possible cause of coccygodynia (in the mother).

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Symtpoms that mimic occygodynia may be the result ofreferred pain, i.e.
pain arising from organs in which disorders are present.
Examples may include conditions or problems in the sigmoid colon, urogenital system, and/or the rectum.
Finally, your coccygodynia maybe be a case of “cause unknown.”
It can also include pain in your lower back and/or hips.
You may find you get a shooting pain down your legs, too.
Coccygodynia intensity varies from person to person.
As mentioned earlier, coccygodynia can be very disruptive to your lifestyle.
You may also find that getting up from a sitting position is difficult.
A coccygodynia diagnosis can sometimes be confirmed by means of an injection.
Research on MRIs
Most of the time an MRI is not used in the diagnosis process.
For example, in the study, out of 172 cases being tested, 105 showed a mobile coccyx.
The surgery for tail bone pain is called a coccygectomy.
They also say that non-surgical treatment works about 90% of the time.
Patijn J, Janssen M, Hayek S, Mekhail N, Van zundert J, Van kleef M.14.
2012;134(1-2):49-55.