A 48-year-old woman with seropositive rheumatoid arthritis presents with this solitary, rapidly expanding and very painful (analog scale 9 out of 10) ulcer on the pretibial surface of her leg. Can you choose the correct diagnosis from the differentials?
A 48-year-old woman with seropositive rheumatoid arthritis presents with this solitary, rapidly expanding and very painful (analog scale 9 out of 10) ulcer on the pretibial surface of her leg.
