Persistence of the sciatic artery: a case report of a combined (complete and incomplete) type causing leg ischemia

Abstract

Persistent sciatic artery is a very uncommon embryologic vascular variant, with a prevalence of 0.05% based on angiographic studies. Two different types of this anomaly can occur, complete or incomplete, on the basis of the relationship between sciatic artery and femoral artery. Although many of these patients are asymptomatic, it may represent a threat to the viability of the lower extremity because of atherosclerotic degeneration resulting in aneurysmal dilatation, occlusive thrombosis, or embolic phenomena with distal complication. We present a case of a 64-year-old man with combined, complete and incomplete, type of persistent sciatic artery causing ischemic ulcer of the first toe.

Figure 1

Photographs of dorsal (a) and plantar (b) ischemic toes of the right foot; the I toe presented an ulceration located at the extremity (arrow). Previous amputation of the III toe is also evident.

Figure 2

(a) Volume Rendering reconstruction of CT-A study. On the right side a large abnormal artery originates from a hypertrophic internal iliac artery and run along the gluteal region and the posterior thigh supplying the entire vascular axis of the leg (arrows). ((b)-(c)) The external iliac, the deep femoral and the superficial femoral arteries showed a slightly reduced caliber but no obstruction (arrowheads). (d) The circulation of calf and foot are regularly patent (arrowheads).

Figure 3

(a) Volume rendering reconstruction of CT-A study. On the left side the same abnormal vessel was depicted (arrows); however, it ended with a progressively reduced caliber at the popliteal level with muscular branches (b) (arrowheads). (c) The distal arterial circulation of the calf and foot was supplied by the superficial femoral artery that presented regular caliber and course (arrowheads).

Figure 4

(a) Maximum intensity projection reconstruction on a coronal plane with bone subtraction technique. No severe signs of atherosclerosis were depicted in the whole peripheral circulation. ((b), (c), (d)) Multiplanar reconstructions on axial plane show, respectively, the course of the sciatic artery (arrows) and that of femoral arteries (arrowheads).