West Ham have only one fit centre-back in their squad as they prepare for a first European semi-final since 1976.
The Hammers travel to Chelsea on Sunday before hosting German side Eintracht Frankfurt on Thursday in the first leg of their Europa League semi-final
Craig Dawson is the only fit centre-back after Issa Diop and Kurt Zouma joined long-term absentee Angelo Ogbonna on the sidelines.
"All clubs get injuries at this time of the season," said manager David Moyes.
The Scot, whose side are five points adrift of fourth place in the Premier League, added: "I've got to juggle and find a way of getting something which gives us a defensive set-up.