Five cases of gluteal fibrosis are presented. The anatomical extent of the gluteal involvement explains the clinical picture. Reports of gluteal fibrosis and fibrosis elsewhere suggest that the lesion was the same in all five patients. Intramuscular injections were a possible etiological factor. All the reported sites were those usually used for administration of intramuscular injections. Because the use of intramuscular injection is so common in Spain another factor is necessary to explain the involvement in only a small number of children.