ASYMPTOMATIC FUNCTIONAL POPLITEAL ARTERY ENTRAPMENT - DEMONSTRATION AT MR-IMAGING

PURPOSE: To determine if functional popliteal entrapment can occur in healthy subjects and to define the mechanism of vascular compression. MATERIALS AND METHODS: The right lower extremities were examined in 13 subjects (nine men 27-34 years of age, mean age 31 years; four women 29-44 years of age, mean age 34 years) with no symptoms of popliteal artery entrapment. Magnetic resonance (MR) and Doppler ultrasound images were obtained while the subjects were at rest and while they performed plantar flexion against resistance. RESULTS: Blood flow during plantar flexion ceased in nine of 13 subjects (69%) and was impaired in three of 13 (23%). MR images showed muscular compression of the popliteal artery at two levels: between the plantaris muscle and the medial head of the gastrocnemius muscle and between the plantaris and popliteus muscles. CONCLUSION: Functional impairment of popliteal arterial flow during plantar flexion occurs in subjects who have no symptoms of popliteal entrapment syndrome.