Context: Patients, who present at the orthopaedic department with a flexible mass in the forearm, are often considered to have an aberrant muscle or other muscle pathology. However, the differential diagnosis also includes different vascular malformations. Case report: We report a 20-year old Dutch woman who presented at the orthopaedic outpatient department with a soft tissue mass of the forearm since seven years. The differential diagnosis includes different vascular malformations, hemangioma, angiosarcoma and accessory muscle. After MR imaging and MR angiography, this mass was diagnosed as an intramuscular slow-flow venous malformation. Treatment consisted of repeated embolization with the sclerosant aethoxysclerol. After five months a control MR Angiograph showed an evident reduction in size of the malformation. Patient had no complaints any more. Conclusion: In fertile woman with a painful swelling located at the wrist or forearm, the diagnosis of a venous malformation should be included in de differential diagnosis. The normal work-up is an ultrasound and if this is suspect for a venous malformation, a MR angiography should be made.
Anne J. Spaans, Lyckle van der Laan, Thijs E.A.M. de Jong and Annechien Beumer