Bleeding diatheses are a hallmark of hemophilia. Hemophilic pseudotumor results 
from multiple episodes of hemorrhage into bones or soft tissue spaces. It is 
uncommon and is seen in severe cases of hemophilia only 1-2% of the time. 
Complications and symptoms arise due to pain and/or compression of surrounding 
structures. Pathologic fractures can be associated with intraosseous lesions and 
can result from bone destruction or resorption due to the chronic pressure of an 
osseous hemorrhage. Radiographs may demonstrate expansile lesions of the bones 
or increased soft tissue density that may be associated with extra osseous 
lesions. Bleeding may also occur within the joint space. These intra-articular 
hemorrhages can, over time, result in hemophilic arthropathy. The following case 
report demonstrates both an expansile lesion of a metacarpal as well as 
hemophilic knee arthropathy in an 11 year old.