Why is Brad Pitt using a cane?

Angelina Jolie and Brad Pitt attend the Palm Springs Film Festival awards gala.

STORY HIGHLIGHTS

• Brad Pitt attended the Palm Springs Film Festival awards gala with the cane on Saturday


• "I was carrying my daughter [Vivienne] down the hill and I slipped," Pitt said


• Pitt says he won't need surgery but he may need that cane for a while

() -- What's 's newest accessory?

A cane -- and it's not just for show.

The actor, 48, walked the red carpet at the 23nd annual Palm Springs Film Festival awards gala with the cane on Saturday, and told reporters he has an injured ACL, a ligament in the knee that connects the femur with the tibia.

"I was carrying my daughter [Vivienne] down the hill and I slipped," Pitt said. "It was either her or me."

Though Pitt says he won't need surgery, he may need that cane for a while.

Not that his partner, , minds.

"I like the cane," she told reporters on the carpet Saturday, adding that the injury hasn't slowed him down much at all. "He's not that kind of guy. He does everything still."

Jolie also said that Vivienne, 3½, wasn't hurt in the tumble.

"Vivie's okay," she told reporters. "She was absolutely fine."

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