Wilshere, on a season-long loan from Arsenal, sustained the injury during Bournemouth’s 4-0 defeat at Tottenham on Saturday and scans have shown a hairline fracture of his left fibula.
The 25-year-old has been ruled out of Bournemouth’s last five league fixtures after the latest in a long line of fitness problems for the injury-plagued England international.
Wilshere made his surprise move to Bournemouth last year to get more playing time and prove his fitness to Arsenal boss Arsene Wenger.
With his spell at Dean Court now over, it remains to be seen whether Wilshere has a future at Arsenal, where he has one more season on his contract.
He started 22 league games for Bournemouth before the fracture, which occurred in a challenge with Tottenham striker Harry Kane.
“It is a big blow to lose Jack. We have loved working with him since he arrived at the club last August,” Bournemouth boss Eddie Howe told the team’s website.
“He has made a huge contribution to our season, both on and off the pitch.
“We wish him a quick recovery and thank him for his effort and professionalism while he was with us.”
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