This case report presents an adolescent patient with type 3 pseudotumor associated with vascular hemophil-ia(von willebrand disease,VWD)of the femur.The patient experienced weakness and pain in the right knee joint for two months following physical activity,with no apparent history of trauma.Genetic testing identified two compound heterozygous mutations in the von willebrand factor(VWF)gene,consistent with a diagnosis of"VWD type 3".Laboratory results revealed a Factor Ⅷ activity of 2.8％,a negative Factor Ⅷ inhibitor test,VWF activity of 1％,and VWF antigen levels below 3％.The desmopressin infusion test(1 hours and 4 hours)showed VWF levels of less than 1％.Imaging studies revealed an osteo-lytic lesion in the right distal femoral epiphysis,characterized by discontinuous cortical resorption in the anterior femur,thin-ning of the medial,lateral,and posterior cortex,prominent sclerotic bands,and extension of the tumor into the distal femoral epiphysis without periosteal reaction.After multidisciplinary consultation,the diagnosis of VWD type 3 pseudotumor of the fe-mur was confirmed.The patient had no history of coagulation factor supplementation and no significant knee trauma.Preopera-tively,the VWF level was maintained above 80％with cryoprecipitate infusion.The lesion was surgically debrided,followed by bone grafting with autologous fibula and allograft bone.Postoperative follow-up at 5 months showed good recovery of knee func-tion.Pseudotumor is a rare but serious manifestation of inherited bleeding disorders,predominantly observed in hemophiliacs.Skeletal muscle system pseudotumor in VWD is exceptionally rare,with previous reports limited to the maxilla and mandible.MRI is crucial for the diagnosis of hemophilic pseudotumor,with characteristic findings of peripheral enhancement without cen-tral enhancement on enhanced scans.Surgery remains the preferred and effective treatment,with adequate perioperative prepa-ration being essential for success.In this case,a multidisciplinary approach was critical in developing a personalized treatment plan,contributing significantly to the patient's positive outcome.
维普
万方数据