Idiopathic aseptic necrosis of the sesamoid bone of the big toe in teenagers and young adults has been described by Renander (1952). We reported three incidents of this condition in adults. The first case was secondary to trauma, whereas repeated trauma could have been responsible for the second. The third case was associated with gout and a multifocal osteo-necrosis. We favor the opinion that idiopathic aseptic necrosis of the sesamoid one of the big toe in adults is seldom a primary condition and that other predisposing factors should be taken into consideration