After a review of the history, clinical features, laboratory findings, imaging techniques and the treatment of coxitis fugax, the authors inform about 131 own cases. In this disease of the hip joint, which is most commonly encountered in childhood, differential diagnosis is of the utmost importance. In the present study, the initial diagnosis had to be changed in eleven cases affected with this condition, which is also referred to as "observation hip". The patients ultimately contracted severe diseases such as leukaemia, juvenile polyarthritis or Perthes' disease.