Actor Zac Efron has opened up about his mysterious hand injury, revealing he broke his wrist while shooting a fight scene with Dave Franco for their new movie Townies.

The High School Musical star was photographed in Los Angeles last week (begs08Apr13) with a large bandage on his right hand and reports suggested he was sent home from the set after being unable to continue filming.

Now Efron has assured fans he is on the mend after undergoing medical treatment to repair the damage.

Showing off a photo of his swollen hand and battle scar during an appearance on U.S. morning show Live! With Kelly and Michael on Thursday (18Apr13), he explained, "I broke it a couple (of) days ago on set... during filming, it was during a stage fight with Dave Franco... I had to go back to work so I couldn't really wear a cast, so they (medics) put like a titanium plate in it and a bunch of screws.

"I don't know why I'm telling you this. My hand in theory is back to normal, it just looks really gross."

It isn't the first time the 25 year old has sustained a bodily injury - last year (12) he sliced open his left hand while cutting a piece of fruit.