Bilateral persistent sciatic arteries with right sciatic artery aneurysm and thromboembolism: a case report

Persistent sciatic artery (PSA) is a rare congenital vascular anomaly. Bilateral complete-type PSA complicated by aneurysm and thromboembolism is particularly uncommon, with limited reports in the literature. Herein, we present a case of bilateral complete-type PSA with right sciatic artery (SA) aneurysm and thromboembolism to improve clinicians' awareness of this rare vascular variant and its management.

A 79-year-old woman presented with sudden-onset right calf pain for 2 days, which had worsened over the past day. An outpatient vascular ultrasound suggested an incomplete occlusion of the right popliteal artery. Computed tomography angiography (CTA) revealed bilateral complete-type PSAs, slender femoral arteries, a right SA aneurysm with thrombosis, and occlusion of the distal SA. Conservative medical treatment was administered owing to advanced age and multiple comorbidities.

PSA is prone to complications, including aneurysmal degeneration and thromboembolism. In this case, physical examination revealed a diminished femoral artery pulse and an undetectable dorsalis pedis artery pulse, while the popliteal pulse was not assessed - highlighting the importance of a thorough physical examination for PSA diagnosis. CTA was the key imaging modality for confirming the diagnosis and assessing complications. The patient achieved significant symptomatic improvement with conservative therapy.

Clinicians should consider PSA in patients with unexplained lower-limb ischemia. A thorough physical examination, including assessment of the popliteal pulse, is essential for early recognition. CTA is the diagnostic modality of choice. For older patients at high surgical risk, conservative medical treatment remains a safe and effective option.