ClassificationsThe disease progresses into 4 chronological stages ( Figure 1):• Condensation stage (Ø 7 months)• Fragmentation stage (Ø 8.5 months)• Reossification stage (Ø 18 months)• End stage [15] Krieg AH, et al., J Orthop Res Physiother 2018, 3: 037 Abstract Legg-Calvé-Perthes disease (or Perthes disease) is a disorder of the hip, which is caused by a vascular disorder ischemia of the femoral head and passes through four stages. It affects mostly infants and children of caucasian population. The cause of the ischemia is not yet known and therefore cannot be prevented norreversed. Limping, restriction of the movement and pain can lead to the diagnosis. X-rays as well as Magnetic Resonance Imaging (MRI) confirms it. The classification of Herring (A-C) is helpful to make a clinical prognosis and further treatment. The main aim of therapy is to improve joint the mobility and the joint's congruence ("containment"), build up muscle strength and reduce pain. Physiotherapy is an undisputed method, lasts over years involving an extensive movement therapy of the affected hip, the torso and the non-affected limb. Short-term drug-related analgesia, botulinum injection into the adductors and a weight relief can accompany therapy. An indication for operative treatment is given by subluxation within stadium B or B/C of Herring. Containment (hip centering/ joint's congruence) can be achieved by femoral varization osteotomy or pelvic osteotomy. Only one quarter of all patients is treated with surgery and physiotherapy remains the most relevant therapy on Perthes disease.