The 24-year-old - on-loan from Chelsea - was added to the growing casualty list at Upton Park when he limped off during the goalless draw at Manchester United on Saturday.
The Hammers were already without fellow attackers Dimitri Payet, Diafra Sakho, Enner Valencia and Manuel Lanzini through injuries at Old Trafford.
But they are hopeful Lanzini will be fit to face Stoke at the weekend after he suffered what was described as a minor injury in training late last week.
Co-chairman David Gold wrote on Twitter: "I'm optimistic that Lanzini will be available for Stoke but we must wait till Tuesday for the scan on Victor."
Ecuador forward Valencia could also be in contention against the Potters after five weeks out with an ankle injury, but Payet and Sakho are not expected back until February
Source : PA
Source: PA