When I get up from sitting on hard surfaces I get pain while standing up and later it is not there. When I sit on soft surfaces it is not there. I saw this article which relates to my problem. Acute pain while moving from sitting to standing. This symptom is particularly interesting, as Dr Maigne found that all of the patients he tested who had pain on moving from sitting to standing had a coccyx that partially dislocated or moved abnormally when the patient sat down. From last 04 wks