Diseases of the hip joint are mainly caused by primary arthrosis. Genetic factors are primarily responsible for this, although physical demands such as load bearing and physical condition (e.g. excess weight and lack of exercise) can play a contributing role. Consequently the cartilage, which is responsible for normal movement of the joint, is increasingly damaged, resulting in painful restrictions of mobility. Along with the causes that lead to primary arthrosis, there are also secondary causes that can encourage the development of arthrosis. Early disturbances of maturation (dysplasia) or infections also play a role. There are, however, other juvenile diseases that, as pre-arthrotic deformities, can lead to a secondary arthrosis of the joint. Conservative therapy consists of medication and physiotherapy, but even in the best case scenario, it can only serve to slow down degeneration. Only surgical therapy represents a sensible option.