Famed artist and inventor Leonardo da Vinci suffered from a crippled right hand late in life, usually attributed to a stroke. In a new paper in the Journal of the Royal Society of Medicine, two Italian researchers argue that Leonardo more likely suffered from a condition colloquially known as "claw hand." They base their argument on analysis of a 16th-century portrait of en elderly Leonardo.
The quintessential Renaissance man was the illegitimate son of a Florentine notary named Piero Fruosino di Antonio da Vinci. (His mother, Caterina, was a peasant.) Much of what we know about Leonardo's life comes from the writing of the 16th-century painter and historian Giorgio Vasari, in Lives of the Most Excellent Painters, Sculptors, and Architects.
Historians have also studied Leonardo's drawings and his use of "mirror writing" in his journals, concluding he was almost certainly predominantly left-handed, although he was ambidextrous to some extent. For instance, he wrote and drew with his left hand but never painted with it. Vasari noted that Leonardo in his prime "was physically so strong that… with his right hand he could bend the ring of an iron door knocker or a horseshoe as if they were lead."
“One cannot indeed expect any more good work from him, as a certain paralysis has crippled his right hand.”
But when Antonio de Beatis, personal assistant to Cardinal Luigi d'Aragona, visited Leonardo's workshop in 1517, he noted in his diary, "One cannot indeed expect any more good work from him, as a certain paralysis has crippled his right hand." This would explain why Leonardo produced far fewer paintings in his last years, although he continued to teach and make many sketches and drawings. His right hand had been damaged, and he could no longer use it to hold palettes and brushes, although he could still write and draw with his dominant left hand.
There was strong consensus among historians that Leonardo likely suffered a stroke (possibly due to a vegetarian diet high in dairy) in his final years that left his right hand gnarled and unusable. Alternatively, he may have suffered from Dupuytren's disease, a rare condition that severely contracts and cripples the hand.
The Italian researchers, Davide Lazzeri and Carlo Rossi, argue that both these diagnoses are wrong. Instead, they advocate that a fainting episode damaged the ulnar nerve in his right hand, leading to ulnar palsy (aka claw hand) and making fine motor movement nearly impossible.
As evidence, they point to a portrait of the elderly Leonardo attributed to Giovanni Ambrogio Figino. (The red-chalk portrait is in the so-called Read More – Source
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