四肢靜脈血管瘤極為罕見，通常於術中才能正確診斷，常會被誤診為其他皮下硬塊，下肢尤為好發部位。目前上肢靜脈血管瘤只有18例被報導，我們要呈現此病例為中前臂靜脈血管瘤併血栓，並且於杜卜超音波呈現水囊病灶無靜脈交通。此病患表現上肢劇痛，且因先前有頸椎退化性關節炎併頸椎神經根病變病史，故誤診為頸椎第六節神經根病變。病理組織檢驗結果為『靜脈管壁呈現異常增厚及擴張併有血栓組織』。靜脈血管瘤併有血栓可能成為栓塞來源，其有致命之風險。因此，當病患有頸椎退化性關節炎併上肢疼痛時，應將靜脈血管瘤併神經壓迫列入鑑別診斷。

A venous aneurysm of the extremities is rare, and it is usually not diagnosed until the time of surgery. It is easily misdiagnosed as other subcutaneous masses. It is mostly located in the lower extremities. Compression of the peripheral nerves by a venous aneurysm is not common. We treated a case of a thrombosed fusiform venous aneurysm of the median antebrachial vein with a duplex study revealing a cystic lesion. It presented as severe forearm pain mimicking C6 radiculopathy caused by C56 and 67 spondylosis. A histological examination showed sclerotic thickening and cystic dilation of the vein with an organized thrombus. A venous aneurysm with thrombosis is a possible source of an embolism which could potentially be fatal. An upper-limb venous aneurysm should be included as a differential diagnosis for cervical radiculopathy.