What is the name of this painting by Quentin Matsys?

Quentin Matsys (1466–1530) was a Flemish painter in the Early Netherlandish tradition. He was born in Leuven. There is a tradition alleging that he was trained as an ironsmith before becoming a painter. Matsys was active in Antwerp for over 20 years, creating numerous works with religious roots and satirical tendencies.

The Ugly Duchess (also known as A Grotesque Old Woman) is a satirical portrait painted by Quentin Matsys around 1513.

The painting was long thought to have been derived from a putative lost work by Leonardo da Vinci, on the basis of its striking resemblance to two caricature drawings of heads commonly attributed to the Italian artist. However the caricatures are now thought to be based on the work of Matsys, who is known to have exchanged drawings with Leonardo.

The painting is in the collection of the National Gallery in London. It was originally half of a diptych, with a Portrait of an Old Man, in the Musée Jacquemart-André, Paris, which was lent to the National Gallery in 2008 for an exhibition in which the two paintings were hung side by side.

A 1989 article published in the "British Medical Journal" speculated that the subject might have suffered from Paget's disease, in which the victim's bones enlarge and become deformed. A similar suggestion was made by Michael Baum, emeritus professor of surgery at University College London.