Frenchman Remy, who scored on his debut last month after signing from Olympique Marseille for eight million pounds, was absent for Saturday's 0-0 home draw with Norwich City.
"I have no idea how long he will be out. We will have to see how he is on Sunday and Monday," manager Harry Redknapp told the BBC. "It was in the last minute of training, and he just struck a ball and felt it go."
With QPR having scored only 18 times in 25 league games this season, the division's weakest attack by five goals, the signing of Remy was seen as a major boost in the club's fight to avoid relegation.
They struggled to break down Norwich in a woeful first half and although Redknapp's side livened up after the break, they were left to rue a missed penalty by Adel Taarabt in the 56th minute.
Despite a fourth draw in a row which left them six points behind fourth from bottom Reading, there were some positives for Redknapp, namely a solid debut for central defender Christopher Samba.
The 28-year-old former Blackburn Rovers rock, who joined for a club-record fee from Russian club Anzhi Makhachkala on Thursday, made some crucial blocks to help Rangers keep a clean sheet.
"Chris Samba was fantastic," Redknapp said. "He's not played since November because of the Russian winter break. We asked him how he was and he said he was about 40 percent fit.
"If that's 40 percent, I don't know what he'll be like when he's 100 percent. He was outstanding."
