heterotopic calcification, arising either idiopathically or as a result of small bone fragments in the soft tissues from either the recent fracture or from small bone chips getting into the soft tissues during surgery. X-rays may or may not show the heterotopic calcification. A repeat x-ray in two or three months may be helpful; by this time it may show the heterotopic calcification.

http://jnm.snmjournals.org/cgi/cont...stract/43/3/346