The dog, named Beatrice, was stolen from her home March 13 and found 11 days later outside a casino with second- and third-degree burns.
The surgery being performed on Monday involves putting pigskin over her burns to let them to heal. A surgeon from Froedtert Hospital and the Medical College of Wisconsin is helping with the procedure.
Dr. John Weigelt says in a statement that even after the surgery, Beatrice will need wound care and additional skin grafts to heal completely.
The Milwaukee County district attorney is considering charging a 21-year-old Milwaukee man identified as a suspect in the case.