MSFinals-0260

A 55-year-old woman has been suffering from significant pain in her lower limbs when walking more than 200 meters for the past six months. During physical examination, her legs appear pale and cool without signs of swelling or redness. The palpation of dorsalis pedis or posterior tibial pulses is not possible. The patient has a body mass index of 33 kg/m2 and has been smoking for 25 pack years. What is the most probable vascular abnormality responsible for these symptoms?