Did da Vinci have a hand deformity?

The San Diego Union-Tribune had this article from last week on a California man who believes Leonardo da Vinci had a hand deformity.

(Ben) Sweeney's research convinced him that da Vinci had a congenital defect – a webbed, or syndactyl, hand. The artist's drawings of his own hand, Sweeney contends, seem to depict a webbed third and fourth finger, characteristic of syndactyly, and a pointed little finger. Sweeney also singles out similarly deformed left hands in other da Vinci artworks – including the hand of Jesus Christ in “The Last Supper.”

Sweeney shared his research with Dr. Joseph Upton at Harvard. Upton is one of the country's leading hand specialists.

“What he has shown me is certainly very believable,” Upton said of Sweeney's research.

While no one will ever be able to prove the theory, “you can't rule it out,” Upton said. He noted that the malformation of the ring finger and third finger depicted in da Vinci's art matches several hand casts in his office.

Upton concluded, “If he didn't have the deformity himself, he certainly saw people who did.” He also said the deformed left hand of Christ in “The Last Supper,” thought by some art experts to be a depiction of da Vinci's own hand after he suffered a stroke, is inconsistent with that of a stroke victim.

Sweeney is in the early stages of his research and it will be interesting to see if his findings get any traction with da Vinci experts and other art historians.