Via Research Recognition Day Program VCOM-Carolinas 2025

Case Reports

Bilateral Complete Persistent Sciatic Arteries: A Rare Case Report of Lower Limb Vascular Complications Ellena Varnadoe, OMS-III, B.S. 1 , David Tabriz, M.D. 2,3 1. Edward Via College of Osteopathic Medicine – Carolinas Campus, Spartanburg, SC

2. Cleveland Clinic Indian River Hospital, Dept. of Vascular and Interventional Radiology, Vero Beach, FL 3. RUSH University Medical Center, Dept. of Vascular and Interventional Radiology, Chicago, IL

Discussion/Conclusion

Introduction

Imaging

Diagnosis The diagnosis of PSA is primarily made through imaging, with computed tomography angiography (CTA) being the imaging modality of choice, providing detailed visualization of the vascular anatomy and associated complications such as aneurysms or stenosis. 1

A persistent sciatic artery (PSA) is a rare congenital vascular anomaly found in approximately 0.025 – 0.04% of the population resulting from the failure of the embryonic sciatic artery to regress. Typically, the femoral artery takes over as the primary blood supply to the lower extremities, but in PSA, the sciatic artery remains patent, traveling alongside the sciatic nerve. 1 PSAs can be classified as complete or incomplete, based on the artery's extent, and categorized into five types (Types 1-5) depending on the relative dominance of the sciatic and femoral arteries (Figure 3) . While most cases are unilateral and asymptomatic, complications such as aneurysms, thromboembolism, and ischemia can occur, 2 making early detection and appropriate management critical. This case describes a rare presentation of bilateral complete persistent sciatic arteries with associated complications and highlights the diagnostic and management approach. A 54-year-old woman with a history of atherosclerotic peripheral vascular disease underwent a recent non-contrast CT pelvis showing concern for a right internal iliac artery aneurysm. A CTA abdomen/pelvis with bilateral lower extremity runoff was ordered to further assess which revealed bilateral complete persistent sciatic arteries (Figure 1) with associated complications, including an aneurysmal dilatation of the internal iliac/persistent sciatic artery origin (Figure 2) . The patient reported no significant symptoms, including no signs of claudication or ischemia. Given the stability of the aneurysmal findings and absence of acute symptoms, the patient was managed non-operatively with close vascular follow-up and imaging surveillance to monitor for progression. Case Description

B

A

Figure 3. Categorization of PSAs depend on the extent of sciatic artery persistence and femoral artery development. 2

Figures 1A (Left) and 1B (Right). Axial Computed Tomography (CT) (A) Axial CT at the level of the acetabulum demonstrates bilateral persistent sciatic arteries ( black arrows ) and bilateral diminutive caliber common and superficial femoral arteries ( white arrows ) (B) Axial CT at the level of the upper thigh reveals bilateral persistent sciatic arteries ( black arrows ) and femoral arteries that remain hypoplastic and poorly visualized peripherally with collateralization likely involving the profunda femoris system ( white arrows )

• Type 1: A complete sciatic a. runs alongside a complete SFA • Types 2-4: Involve varying degrees of both arteries • Type 5: A complete PSA originates from the median sacral artery (MSA) with an incomplete or absent SFA • Complete: the sciatic artery extends the full length of the limb • Incomplete: The sciatic artery does not extend the full length of the limb Treatment The management of PSA is individualized, with a focus on the severity of symptoms and complications. Asymptomatic cases are generally observed, while symptomatic cases necessitate surgical or endovascular interventions. 1 Awareness of a PSA is crucial to ensure timely diagnosis and management, reducing the risk of potentially severe complications that may lead to amputation.

• Bilaterally: Bilateral complete persistent sciatic arteries ( white arrows ) • Right lower extremity: A 2.4 cm aneurysmal dilatation at the origin of the internal iliac/persistent sciatic artery ( black arrow ) • Left lower extremity: Occlusion of the common and external iliac arteries with reconstitution of flow in the persistent sciatic artery ( orange arrow ) Figure 2. 3D Volume-Rendered Computed Tomography Angiography (CTA)

References

1. Kumar, S., & Suresh, K. R. (2023). A hybrid approach to persistent sciatic artery fusiform aneurysm repair. Journal of Vascular Surgery Cases, Innovations and Techniques . Advance online publication. https://doi.org/10.1016/j.jvscit.2023.101280 2. van Hooft, I. M., Zeebregts, C. J., van Sterkenburg, S. M. M., de Vries, W. R., & Reijnen, M. M. P. J. (2009). The persistent sciatic artery. European Journal of Vascular and Endovascular Surgery, 37 (5), 585 – 591. https://doi.org/10.1016/j.ejvs.2009.01.014

2025 Research Recognition Day

100