The second edition presents a comprehensive book on Perthes disease. The previously unclear clinical picture is described from the history through the etiopathogenesis, diagnostics, differential diagnostics, and therapy to the prognosis. In addition to classical clinical and radiological diagnostics, newer methods such as sonography, scintigraphy, computed tomography, and magnetic resonance imaging are discussed and evaluated. The authors present the conflicting views on therapy side by side and develop a unified yet differentiated treatment concept based on their own clinical and experimental studies, which is oriented towards age, the clinical picture, and prognosis.