The authors of the study present four case studies of sudden onset coccydenia with calcium crystal deposition in the sacrococcygeal or intercoccygeal joints.
Common coccydenia is usually characterized by persistent or chronic pain. It is usually localized to the coccyx with sitting, or arising from sitting. It is usually caused by disc degeneration, instability, deformity of the coccyx, and trauma.
For several years, it has been known that calcium crystal deposition in an intervetebral disc can be the source of acute pain. Calcium crystal deposition has never been reported as the likely cause of acute onset coccydynia, however. Since sacrococcygeal and intercoccygeal joints can contain a thin intervertebral disc, it is reasonable to have calcium crystal deposition.
Forty percent of the time, plain lateral radiographs in standing and then in sitting will not reveal any abnormalities with common coccydynia. These standard radiographs demonstrated calcium crystal deposition of the sacrococcygeal or intercoccygeal joints in all four of the case studies presented. Following treatment with corticosteroids either orally or injected, three of the four subjects had normal radiographs. They also had significant or complete resolution of coccygeal pain.
First line treatment for common coccydynia is oral analgesics and sitting aides. If this is ineffective, corticosteroid injection into the caudal epidural space, sacrococcygeal space, or ganglion injections can be helpful. Removing the coccyx has been a treatment option when other treatments are ineffective.
The authors suggest that persons with sudden onset coccydynia should be evaluated with radiographs. If calcium deposition is found in the sacroccygeal or intercoccygeal joints, treatment should include short course of oral corticosteroids, or steroid injection into the involved joint.