Rare Mixed Pseudoaneurysm and Pyogenic Granuloma of the Thumb Radial Digital Artery.

Pseudoaneurysms of the digital arteries are rare, with fewer than 20 cases reported. They typically result from partial vessel wall injuries due to trauma, repetitive microtrauma, or iatrogenic causes. Their rarity is attributed to the small diameter of the digital arteries, which makes complete laceration or thrombosis more likely than partial injury. We present the case of a 43-year-old man who developed a thumb radial digital artery pseudoaneurysm after workplace trauma. Initially misdiagnosed, the patient underwent unsuccessful bedside drainage at an urgent care center. Clinical examination revealed a 2 × 2 cm mass on the volar, radial aspect of the proximal thumb phalanx. Doppler ultrasonography confirmed the diagnosis of a pseudoaneurysm. Surgical intervention, performed 10 months postinjury, revealed a 15-mm mass continuous with the radial digital artery. The pseudoaneurysm was successfully resected via artery ligation. Microscopic examination revealed mixed features of both pseudoaneurysm and pyogenic granuloma, presenting an even rarer clinical entity. To our knowledge, this is the first report of a mixed pseudoaneurysm and pyogenic granuloma located in the radial digital artery of the thumb. This case underscored the importance of considering complex vascular anomalies in persistent digital masses posttrauma and emphasized the value of comprehensive histological examination for accurate diagnosis.