RESUMEN
INTRODUCTION: in his Libro del exercicio y de sus provechos (Book of exercise and profits), the Spanish Renaissance physician Christopher Mendez (1500-1553) describes extracting a bulk stone from the bladder of a child younger than 5 years in the land of colonial Mexico. This is the first description of a surgical procedure in America. MATERIAL AND METHODS: Biographical data were collected on Christopher Mendez. The electronic facsimile of the Book of exercise and profits was read. The historical aspects of perineal lithotomy and etiology of bladder stones were analyzed. RESULTS: In chapter seven of the third treatise (page 120), Mendez speaks about the removal of a bladder stone in a boy named «Villaseñor¼. It uses the word «open¼ to describe the procedure, corresponding to a lithotomy more than a necropsy. It attributes the etiology of excess movements after ingestion and suggests a possible hereditary etiology. DISCUSSION: Perineal lithotomy was a common practice in ancient times for children due to the high incidence of bladder stones. The technique was very invasive and was improved over the centuries. CONCLUSIONS: The surgery described by Mendez for the child called Villaseñor most likely corresponds to a perineal lithotomy. A congenital cause could play a role in its etiology.