Julius Wolff (21 March 1836 – 18 February 1902) was a German surgeon. Biography Julius Wolf was born on 21 March 1836 in Märkisch Friedland, and received his doctorate in 1861 in the field of surgery under Bernhard von Langenbeck (1810–1887) at Friedrich-Wilhelms University in Berlin. In 1861 he settled down after the state examination as a general practitioner in Berlin. He participated as a surgeon in three military campaigns (1864, 1866, 1870/71). Based on observations in his long career as a surgeon, he postulated Wolff's law (original title 1892: The law of transformation of the bone), which describes the relationship between bone geometry and mechanical influences on bone. For this he was with leading scientists of his time in active contact. Karl Culmann (1821–1881), Wilhelm Roux (1850–1924), Christian Otto Mohr (1835–1918) and Albert Hoffa (1859–1907) gave him support for the interpretation and evaluation of its research. His work established the mechanism and thus physical factors in evolutionary biology. He saw his work as an extension of the theory of evolution by Charles Darwin (1809–1882). His work was one of the mile stones for orthopedics as a distinct discipline in medicine. Julius Wolff was the first professor of orthopedics at the Charité and the founder and director of the first Department of Orthopaedic Surgery in Berlin. His scientific work has to this day a significant impact on orthopedic surgery. His findings that adapted bone altered mechanical conditions found today in application of musculoskeletal research, orthopedics, trauma surgery, rehabilitation, mechano-and cell biology and tissue engineering. He died on 18 February 1902 of a stroke. Bibliography 1860 De artificiali ossium productione in animalibus, Diss. Kaiser Wilhelm Universität Berlin 1863 Die Osteoplastik in ihren Beziehungen zur Chirurgie und Physiologie. Archiv für Klinische Chirurgie 4: 183-296 1868 Ueber Knochenwachsthum. August Hirschwald, Berlin, Berliner klinische Wochenschrift 5(6): 62-64, 76-77, 110-112 1869 Ueber die Bedeutung der Architectur des spongiösen Substanz. Zentralblatt für die medizinischen Wissenschaft VI: 223-234 1870 Über die innere Architektur der Knochen und ihre Bedeutung für die Frage vom Knochenwachstum. Virchow’s Archiv 50(3): 389-453 1872 Beiträge zur Lehre von der Heilung der Fracturen. Archiv für klinische Chirurgie 14: 270-312, 389-453 1873 Zur Lehre der Fracturheilung. Deutsche Zeitschrift für Chirurgie 2(6) 546-551 1875 Ueber die Expansion des Knochengewebes. August Hirschwald, Berlin, Berliner klinische Wochenschrift 6, 8 1875 Einige Bemerkungen zum gegenwärtigen Stand der Knochenwachsthumsfrage. Virchow’s Archiv 64:140-144. 1877 Ueber den Gudden’schen Markirversuch am Kaninchenschädel. Verhandl.