[Osteoid osteoma. 5 cases].

With reference to five cases of osteoid osteoma, including two para-articular cases with articular reaction, two cases with neurological manifestations, and one case with a rare costal lesion, the authors demonstrate the difficulty of diagnosis in this disease, which is, in principle, well known. In some cases the observations extended over seven years. The authors also review the literature on this subject.