The wicketkeeper-batsman appeared to pick up a knock while hitting a six in Saturday's win over Bangladesh, although he carried on batting after receiving treatment.
The 28-year-old smashed 64 from 44 balls but did not keep wicket, with Jonny Bairstow taking the gloves.
Captain Eoin Morgan insisted after a 106-run victory that Buttler stayed off the field as a precautionary measure and England are hoping he will make a swift return.
"Jos sustained heavy bruising on his right hip during the match against Bangladesh at Cardiff," said an England spokesperson.
"He is responding well to treatment and will be reassessed later this week.
"We anticipate he will train with the rest of the squad at the Hampshire Bowl on Wednesday ahead of the match against West Indies on Friday."