Remission of idiopathic thrombocytopenic purpura after femoral lengthening. Clinical case followed for 5 years.

We report on a patient with chronic idiopathic thrombocytopenic purpura (ITP) who went into remission after femoral lengthening. Although it is possible that spontaneous remission (frequency 5%-10%) of chronic ITP coincided with the femoral lengthening, limb lengthening could also have caused the thrombocytosis. This case suggests a close relationship between osteogenesis and hematopoiesis during regenerate bone formation. Limb lengthening can therefore be defined as the formation not only of bone and soft tissue but also of hematopoietic tissue.