The popliteal artery is located in the leg roughly between the lower third section of the upper leg and the upper third section of the lower leg and is quite deep beneath the skin. It supplies blood to the lower leg including the calf and foot.
Popliteal aneurysms are relatively uncommon compared to abdominal aortic aneurysms, although there is a greater risk of developing a popliteal aneurysm if you have or have had other aneurysms. The vast majority of patients with this type of aneurysm are male and aged around 70.
Although what exactly causes popliteal aneurysms is unknown, there is a link with atherosclerosis (arterial blockages). Unlike other types of aneurysm where the major risk is a rupture of the aneurysm, this is much less common with popliteal aneurysms. The greater risk is of blood clots forming in the artery and then flowing down the leg ('embolisation') and blocking blood supply to the lower leg (lack of blood supply to tissue is called 'ischaemia'), and this occurs in roughly 30-50% of cases within a 3-5 year period.
Where severe ischaemia sets in, usually accompanied by severe pain and numbness and/or difficulty in moving the leg or paleness of the skin in the leg, it must be treated within 6-12 hours, otherwise the leg may need to be amputated.
Popliteal aneurysms are usually diagnosed using ultrasound scan or CT angiogram.
Read more on surgical treatment for popliteal aneurysms: