Experts believe the famous Mona Lisa artwork may be unfinished.
It's thought Leonardo da Vinci had a severe fainting episode leaving him with a "claw" hand, unable to hold a paintbrush.
A portrait of the artist shows his right hand wrapped in bandages.
Even though da Vinci drew with his left hand, he painted with his right too.
Rsearchers believe the injury may have forced him to leave many works incomplete.

Son of filmmaker Rob Reiner jailed on suspicion of murdering parents
Seven New Year countdowns to light up Global Village
Police probe deaths of filmmaker Rob Reiner and wife as apparent homicide
Disney's 'Zootropolis 2' set to join $1 billion box office club
Reddit sues Australia over social media ban
