Vermaelen, who moved from Arsenal in August in a deal worth a reported €19 million, has yet to feature for Barca due to the problem, which he picked up while representing Belgium against Russia at the World Cup.
Though he has returned to training numerous times, the club's doctors are yet to clear him to play.
And the 29-year-old is now in danger of missing the entire campaign after Barca confirmed an operation was necessary.
"First team footballer Thomas Vermaelen will undergo surgery on his right semitendinosus muscle by doctor Sakari Orava next Tuesday in Finland," a statement on Barcelona's official website read.
"The estimated recovery time is 4 to 6 months."
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