Aneurysm of the popliteal artery can occur in isolation, or in association with other large vessel aneurysms (eg, abdominal aorta, femoral artery). Popliteal aneurysm is often diagnosed as a result of screening tests or other imaging studies (other aneurysm, peripheral artery disease) in patients who do not have obvious symptoms of vascular disease. When symptoms are present, they are due to a variable degree of lower extremity ischemic symptoms that can include claudication, distal ischemia due to chronic embolization or acute limb-threatening ischemia due to thrombosis of the aneurysm or acute thromboembolism . Patients with symptomatic popliteal aneurysm should be referred for vascular evaluation and repair. The management of asymptomatic popliteal aneurysms depends upon patient comorbidities, the size of the aneurysm and the presence or absence of arterial thrombus.
Issues related to popliteal artery aneurysm will be reviewed here. The surgical and endovascular management of popliteal aneurysm is discussed separately. (See "Surgical and endovascular repair of popliteal artery aneurysm".)
Popliteal anatomy — The popliteal artery is in continuity with the superficial femoral artery. Anatomic landmarks include the tendinous insertion of the adductor magnus muscle in the distal femur superiorly, and the bifurcation of the popliteal artery into the anterior tibial artery and tibioperoneal trunk at the level of the tibial tuberosity inferiorly.
Popliteal aneurysms are true aneurysms involving all layers of the vessel wall (intima, media, adventitia). Pseudoaneurysm formation in the popliteal artery has also been described but is rare .
Popliteal aneurysms are described as fusiform (ie, diffusely dilated) or saccular (ie, rounded and typically asymmetric). Fusiform dilation of the popliteal artery may be contiguous with fusiform dilation of the superficial femoral artery . Aneurysm shape may have clinical implications. (See 'Rupture' below.)