Leonardo da Vinci's 16th-century drawing suggests that the artist sustained traumatic nerve injury to his right hand that impaired his painting skills later in life. The findings of the study are published in the Journal of the Royal Society of Medicine.
While the impairment affected his ability to hold palettes and brushes to paint with his right hand, he was able to continue teaching and drawing with his left hand. According to most authors, the origin of da Vinci's right-hand palsy was related to a stroke.
Doctors reached a different conclusion after analyzing a 16th-century drawing of an elderly da Vinci, together with a biography and an engraving of the Renaissance polymath artist and inventor in earlier years.
Dr Lazzeri said: Rather than depicting the typical clenched hand seen in post-stroke muscular spasticity, the picture suggests an alternative diagnosis such as ulnar palsy, commonly known as claw hand."
He suggests that a syncope, or faint, is more likely to have taken place than a stroke, during which da Vinci might have sustained acute trauma of his right upper limb, developing ulnar palsy. The ulnar nerve runs from the shoulder to little finger and manages almost all the intrinsic hand muscles that allow fine motor movements.
While an acute cardiovascular event may have been the cause of da Vinci's death, his hand impairment was not associated with cognitive decline or further motor impairment, meaning a stroke was unlikely. Dr. Lazzeri said: "This may explain why he left numerous paintings incomplete, including the Mona Lisa, during the last five years of his career as a painter while he continued teaching and drawing."