Buttler sustained the injury while playing against Sri Lanka at Headingley. Although he briefly returned to batting, he was later unable to continue and was withdrawn from the match.
His participation in England’s tour of Australia in November is also reportedly in doubt as the team management assesses the severity of his injury.
In Buttler’s absence, Jordan Cox is expected to take on wicketkeeping duties while receiving an extended opportunity in the middle order. Cox scored 76 off 52 balls in the series-deciding ODI against Sri Lanka, recording his first half-century in the format.
England head coach Brendon McCullum said injuries to key players can also provide an opportunity to assess replacements ahead of the World Cup.
He added that England must plan in advance for potential challenges and ensure the squad has sufficient depth.