Ella Harper was affected by a rare orthopedic deformity which led to her knees bending in an abnormal way. Due to her condition, Ella found it easier to walk on all fours. This gave her the name of the ‘Camel girl’. She was the star in W. H. Harris’s Nickel Plate Circus.(source)
Simon Metz was also famous for his role in the 1932 movie, freaks. He had neurodevelopmental disorder known as microcephaly. Which affected his physical appearance, which resulted leaving him with a small skull.(source)
Englishman Joseph Merrick was inflicted by many severe deformities. While the exact nature of these conditions is unknown, many believe it was a severe version of Elephantiasis. More recent research also suggests it might have been a combination of neurofibromatosis type I and Proteus syndrome.(source)