Tikkanen, who had struggled with 12 goals and 16 assists in 38 games, was injured Saturday in a 3-2 win over the Calgary Flames after being hit into the boards.
Originally, Tikkanen's injury was described by team doctor Gordon Cameron as a bruise. "There's no sign of dislocations," he told an Edmonton newspaper.
But yesterday, the Oilers released a statement in which team surgeon Dr. David Reid said Tikkanen will require surgery to repair the damage.
Forward Anatoli Semenov, who also was hurt Saturday, suffered a mild shoulder separation, the Oilers said. He and goaltender Bill Ranford, who pulled a groin muscle Saturday, are out of the lineup on a day-to-day basis.
Goaltender Peter Ing and forward Martin Rucinsky were called ZTC up from the Oilers' American Hockey League affiliate at Sydney, Nova Scotia, to replace the injured players.
* SHARKS: Link Gaetz was released on nominal bail after appearing in provincial court following his arrest on several outstanding warrants.
Gaetz was arrested at Vancouver International Airport as he arrived with the team. Gaetz was wanted on two wilful damage charges and a dangerous driving charge.