Popliteal Artery Aneurysm in a Young Intravenous Drug User: A Case Report.

Introduction: Introduction: Popliteal artery aneurysms (PAAs) are rare in young adults and typically associated with atypical etiologies such as trauma or infection. Case Report: We report the case of a 35-year-old male intravenous (IV) heroin user presenting with a 1-week history of progressive left knee pain and a pulsatile mass in the popliteal fossa. Clinical examination revealed significantly diminished distal pulses and a cool extremity distal to the knee. Initial X- ray identified a retained foreign body (needle) in the popliteal soft tissues, and contrast enhanced computed tomography angiography confirmed a ruptured 5.8 × 3.0 cm PAA with active contrast extravasation and luminal compression. The patient underwent urgent surgical intervention through a posterior approach. Following resection of the diseased aneurysmal segment, vascular reconstruction was performed using an autologous reverse saphenous vein graft harvested from the ipsilateral limb. To protect the vascular repair and prevent mechanical stress on the graft in the high mobility popliteal zone, an across knee external fixator was applied with the knee maintained in 30° of flexion. The post-operative recovery was uneventful, with immediate restoration of distal perfusion. At the 6-week follow-up, repeat angiography confirmed excellent graft patency, allowing for the removal of the external fixator and the initiation of a mobilization program. Conclusion: This case emphasizes the importance of maintaining a high index of clinical suspicion for vascular complications in IV drug users and timely surgical intervention to prevent limb-threatening complications.