We reviewed the cases of thirty-one patients (thirty-four hips) who had had severe Legg-Perthes disease (Catterall group III, five hips and group IV, twenty-nine hips) and had been treated with a weight-bearing abduction orthosis, to determine the effectiveness of the brace. The mean age of the patients when they were first seen was six years (range, three to twelve years). The mean duration of follow-up was seven years (range, two to thirteen years). At the most recent follow-up, all hips were rated with the method of Mose and the classification of Stulberg et al. According to the criteria of Mose, no hip had a good result, twelve (35 per cent) had a fair result, and twenty-two (65 per cent) had a poor result. On the basis of the classification of Stulberg et al., there were fourteen (41 per cent) class-II results, eighteen (53 per cent) class-III and IV results, and two (6 per cent) class-V results. Although containment is the most widely accepted principle of treatment for patients who have Legg-Perthes disease, and the Atlanta Scottish Rite-type orthosis is the most commonly used orthosis for this condition, there are few clinical data supporting the effectiveness of this device. On the basis of our results, we do not recommend the use of a weight-bearing abduction brace for the treatment of severely involved hips.