It is unlikely that he will be fit to play again this season. He will see the specialist again today (Monday) and it is anticipated that he will undergo an operation to stabilise the fracture.
Meanwhile, Rob Dewey will return to Scotland this summer where he will link up with Glasgow Warriors after two seasons with Ulster Rugby.
Dewey's two-year contract with Ulster expires at the end of the season, and the Scotland-capped centre has signed a three-year deal with Glasgow.
Dewey originally played for Edinburgh before his move to Belfast at the start of the 2007/08 season but he has not featured regularly for Ulster this season and will return to Scotland where he hopes to have the opportunity to impress the national management.
"It's going to be tough to earn a place in a very competitive Glasgow back-line, however, I'm looking forward to the challenge," he said.
"I also believe in the importance of being in Scotland, in front of the national coach, for getting myself back into contention for future Scotland honours."
Dewey will remain part of the Ulster squad until the end of the current season.