Leonardo da Vinci's Painting Skills Faded After He Fainted And Damaging His Right Hand: Study

mona lisa da vinci
Experts believe Leonardo da Vinci may have left the Mona Lisa unfinished because of an injury to his right arm. Pixabay/Pexels

Leonardo da Vinci's painting skills wore away towards the end of his life because he suffered nerve damage to his right hand after fainting, according to a study.

The research questions previous work suggesting the Italian polymath experienced a stroke that affected the use of his right hand.

Experts have long debated to what degree Leonardo was ambidextrous. It's almost certain he was left-handed. And while he was more skilled than most at painting with his left hand, it is believed he only painted with his right. A separate study published last month supported this theory.

Dr. Davide Lazzeri, co-author of the new study and a specialist in plastic reconstructive and aesthetic surgery at the Villa Salaria Clinic in Rome, told Newsweek scientists know for sure that in 1517 Leonardo had a "certain paralysis of his right hand" because of a diary entry by Antonio de' Beatis, the personal assistant of the influential Italian cardinal Luigi d'Aragona.

To find out more about what caused Leonardo's injury, the authors of the research, published in the Journal of the Royal Society of Medicine, studied a number of historical artifacts. These included a 1505 engraving of a man playing an instrument similar to a fiddle by the Renaissance artist Marcantonio Raimondi, which experts recently realized was a depiction of Leonardo. This suggests he had good use of both of his hands at this time, the authors argued.

A later undated 16th-century portrait of an elderly Leonardo etched in red chalk by Giovan Ambrogio Figino, an artist working in Milan, was also assessed. This showed the Renaissance man with his right hand in a "stiff, contracted position," according to the study.

It was thought that Leonardo suffered a stroke, but the way his hand is positioned suggests his right hand was more harmed by ulnar palsy, or what is known as "claw hand."

What's more, it is unlikely that a stroke serious enough to affect Leonardo's use of his right hand wouldn't have also impacted his other limbs, his face, or caused a cognitive impairment, said Lazzeri.

"Leonardo went on teaching to his pupils and de' Beatis did not describe any other sign or symptoms related to a post-stroke condition."

Lazzeri said trauma to his arm caused by a fainting episode would explain why Leonardo was unable to hold a palette, brush and paint in his right hand and his "undamaged ability to draw, sketch and write with his left hand."

Despite the efforts of the researchers, they were forced to rely on a retrospective diagnosis based on biographic information and portraits, which presents some limitations for their conclusion, acknowledged Lazzeri.

"It would be fascinating to investigate Leonardo's skeleton to verify at least the presence of fractures or trauma," he said.

The research could be followed up by work looking at whether problems with his right hand explain why Leonardo didn't finish a number of paintings, including his portrait of the Mona Lisa.

The study coincides with the 500th anniversary of the genius's passing. "Five centuries after his death, during which thousands of scholars have read his works, have discussed his discoveries and have investigated his life from every point of view, there is still a lot to know about Leonardo da Vinci, the 'Renaissance Man,'" Lazzeri said.