Solitary osseous capillary-type vascular malformation of the distal humerus in a child.

Vascular malformations are abnormal proliferations of the endothelial lining of the blood vessels that are most commonly found in skin and can penetrate the local soft tissue and muscle. Only 1% of all vascular malformations are found in the bone. Skeletal vascular malformations of the long bones, including the humerus, are extremely rare entities that are particularly uncommon in children. Only 4 reports involving the humerus have been described in children previously. We present the case of an intraosseous capillary vascular malformation of the right distal humerus in a 3-year-old boy. Definitive treatment was successful with a single operation using curettage and intramedullary decompression with grafting of an osteoconductive calcium sulfate pellet filler and autogenous bone graft. This is, to our knowledge, the youngest reported case of a solitary intraosseous capillary vascular malformation involving the distal humerus.