Popliteal artery entrapment syndrome: more common than previously recognized

This report summarizes our experience with the popliteal entrapment syndrome in 88 limbs (48 patients) treated during a 10-year period.

The study cohort consisted of a retrospective analysis of those patients who were seen with symptoms of claudication or severe ischemia by a single surgical group and in whom unequivocal evidence of popliteal entrapment was shown either with angiography or at the time of operation. The cases were collected prospectively in a private vascular surgical practice.

Bilateral popliteal entrapment was found in 40 of the 48 patients. The mean age at the time of presentation was 35.0 years (SD, 11.6 years). Claudication was the most frequent presenting symptom (70 of 88 limbs). Types I, II, III, and IV popliteal entrapment were found in 58 limbs (15 arteries occluded), and 30 limbs (three occlusions) were seen with a "functional" popliteal artery entrapment (apparent absence of a developmental anatomic abnormality). Of the 18 limbs with severe ischemia and associated occlusion of the popliteal artery, 15 underwent bypass grafting with reversed saphenous vein grafts, all of which remained patent during the follow-up period (median follow-up, 4.2 years; range, 1 to 10 years). One popliteal artery occlusion that was treated with thrombectomy and vein patching occluded within 6 months and necessitated subsequent vein grafting. Two limbs with inoperable occluded popliteal arteries were not subjected to reconstruction (one necessitated amputation because of advanced ischemia, and the second had extensive thrombosis of the distal run-off). In two patients (four limbs), moderate presenting symptoms abated without surgery after the discontinuation of an extreme exercise program. The remaining limbs underwent surgical decompression (all popliteal arteries remained patent, with a median follow-up of 3.9 years).

The popliteal entrapment syndrome is more prevalent than has formerly been appreciated. On the basis of observations made in this series and in the surgical literature, we advise surgical correction in all cases of types I, II, III, and IV entrapment at the time of diagnosis to avoid occlusion as a result of continued arterial wall degeneration. In contrast, decompression is only advised in those patients with "functional entrapment" if they have discrete and typical symptoms because up to 50% of the normal population may display transient popliteal artery compression with extremes of plantar flexion or dorsiflexion. On the basis of the severe histologic changes found in those popliteal arteries that had undergone occlusion at the time of presentation, it is advised that the popliteal artery should be completely replaced, ideally with a vein graft, when significant degeneration or occlusion of the popliteal artery is noted at the time of operation.