Acute limb ischaemia due to thrombosed persistent sciatic artery aneurysm presents a surgical challenge in a frail...

Persistent sciatic artery (PSA) is a rare congenital anomaly, whereby the embryonic sciatic artery remains patent with associated degrees of femoral axis hypoplasia. Aneurysmal degeneration and distal ischaemia from thromboembolic complications are common. Revascularisation strategies include embolectomy, bypass or interposition grafting and catheter-directed thrombolysis.

We describe a sedentary 88-year-old woman with right acute limb ischaemia secondary to a thrombosed PSA aneurysm and concurrent occlusive thrombus at the femoral bifurcation.

The patient presented with a 3-day history of a cold, painful right foot. Examination revealed Rutherford IIb ischaemia. CT-angiography demonstrated no continuity between the hypoplastic superficial femoral and popliteal arteries, complete occlusion of the right PSA distal to the thrombosed aneurysm and occlusive thrombus in the right profunda. As she was too frail for femoral-distal bypass, we restored femoral axis inflow via profunda embolectomy. Her prognosis remained guarded as we deliberately did not reconstruct the PSA. However, she was discharged pain-free and mobilising with aids 2 weeks later.

Limb ischaemia in frail, high-risk patients is an ever-increasing challenge for vascular surgeons and requires complex decision-making, balancing comorbidities against desired outcomes. This case illustrates that a selective approach can be sufficient to maintain function despite complex anatomy.