Osteotomy is one of the most common surgical procedures performed everyday all over the world. This technique dates back to the first half of nineteenth century and to the fundamental contribution made by Pennsylvania Hospital surgeon John Rhea Barton (1794-1871), who can be considered the pioneer of modern osteotomies; this paper focuses on his life and career highlights with a description of the first corrective osteotomies for hip and knee ankylosis (documented in two fundamental papers whose original pictures are here reproduced). The success of osteotomy as a current surgical approach to treat several orthopaedic conditions is confirmation of the importance of this procedure in the orthopaedic discipline and prompted an investigation into the pioneering mind who introduced it.