The former Manchester United stopper broke the bones after a challenge from Oldham attacking midfielder Robbie Simpson during the FA Cup fifth round replay at Goodison Park last month.
He flew back to his homeland for surgery and recuperation, but manager David Moyes believes he will be back quicker than what many expected.
He said: “He has two fractures, but they are not the bones which are supporting anything, it is off the spine. They are not weight bearing.
“It is not like a pure fracture where we need to wait to look at it. It is a question of whether he can cope with the pain because the bones will heal themselves, but it’s not good.”
The 34-year-old has made over 250 league appearances for the Toffees, and even has a goal to his name with the bizarre effort that flew over Adam Bogdan’s head in a Premier League game with Bolton Wanderers last January.
Before missing the win over Reading this month, Howard had made 210 consecutive top flight appearances for the Merseysiders, dating back to September 2007. He has also won 72 caps for the United States.
Jan Mucha will continue to deputise in goal for this Saturday’s visit of Premier League champions Manchester City.
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