The Ibrox number one was forced to miss Sunday’s 2-1 victory over Hearts due to a long-standing complaint as Jak Alnwick came in to deputise.
Murty has hinted Foderingham might also have to sit out next Sunday’s Old Firm showdown, where Brendan Rodgers’ treble-chasers only need a draw to seal a seventh straight title.
Losing his first-choice keeper is the last thing Murty needs after watching Rangers lose to Celtic in last weekend’s William Hill Scottish Cup semi-final.
But there could be further bad news for the manager as he revealed defender Bruno Alves is also struggling after pulling up during that 4-0 defeat.
“Wes has been struggling with an issue for a while and we thought it was right he didn’t play,” said Murty. “He ruled himself out himself because of it.
“He thought it was too much now for him to cope with. But I thought Jak came in and did really well.
“As for next week, we’ll have to assess Wes later on.
“Bruno has got a hamstring pull from last week. Again we’ll have to see how he is for next week. It’s too soon to say right now.”
Rangers were forced to undergo a week of soul-searching after their derby disaster.
Fans made their feelings clear as they held a silent protest during the Hearts game, while the Union Bears group unveiled a banner which insisted the supporters “deserve better” both on and off the pitch.
But there is likely to be another dark day in store next weekend as Celtic look to celebrate their latest title triumph in front of the beleaguered Light Blues.
Murty, though, has not ruled out the possibility of his team spoiling the party.
“I see it as a massive game for this football club,” he said after goals from Jason Cummings and Daniel Candeias sealed victory over Hearts.
“That’s why the split was introduced, to give us massive games every week, and there is none bigger than Rangers and Celtic.
“We didn’t turn up at the last one in a way which would represent ourselves in a correct manner. We know that.
“We started back today by doing simple things really well with intensity and quality. We need to do more of the same.”