Personal physician to Caliph Al-Hakam II in Umayyad Córdoba, Al-Zahrawi (Abulcasis) wrote the Kitab al-Tasrif, a thirty-volume medical encyclopedia whose final volume — devoted exclusively to surgery — was history's first illustrated surgical manual, with diagrams of over 200 instruments he designed or refined. He performed the first documented thyroidectomy in history and was the first physician to formally record the hereditary nature of hemophilia. He introduced catgut for internal sutures and described obstetric and dislocation-reduction procedures European medicine would later claim as its own. Translated into Latin by Gerard of Cremona in the 12th century, his surgical treatise was the standard manual in European universities for over 500 years.