Utility of Duplex Ultrasound in the Diagnosis and Treatment of Functional Popliteal Artery Entrapment Syndrome.

A 19-year-old female presented with intermittent claudication without anatomical abnormality in the popliteal fossa on magnetic resonance imaging and computed tomography. However, duplex ultrasound (DUS) showed compression of the popliteal artery (PA) and vein during plantarflexion and dorsiflexion. She was diagnosed with functional PA entrapment syndrome (PAES) and underwent resection of the plantaris and gastrocnemius muscles using DUS with stress maneuvers, which relieved the symptoms. In physically active adults, functional PAES can develop without anatomical abnormality. Thus, in the field of vascular medicine, it is important to consider this underrecognized pathophysiology among young people with lower leg pain.