When a weak area of a blood vessel expands or bulges greatly, physicians call it an aneurysm. A popliteal artery aneurysm is an abnormal bulge that occurs in the wall of the popliteal artery, which supplies blood flow to the knee joint, thigh and calf. A popliteal aneurysm can rupture, and in turn cause life-threatening uncontrolled bleeding as well as a blood clot, potentially leading to amputation of the affected leg.
Many individuals who have popliteal aneurysms have no symptoms. However, some common symptoms that can occur include:
· Pain behind the knee
· Pain or numbness in the foot
· A collection of watery fluid in the lower leg
· Painful sores or ulcers on the skin of the feet that don’t heal
· Gangrene (tissue death)- usually requires some form of amputation
The exact cause of popliteal aneurysms remains unknown, though researchers believe that atherosclerosis, also called “hardening of the arteries” plays a key role. As an individual age, their arteries become blocked through atherosclerosis, a liquidly substance called plaque that assembles in the walls of the arteries. Over time, it can cause the arteries to harden and possibly weaken.
A few factors that can increase the risk of developing a popliteal artery aneurysm include:
- Being a smoker
- Being overweight
- Having high blood pressure
- Having high cholesterol levels
- Having a family history of heart or vascular disease
- Having blood vessel reconstruction done in one or both of the legs
Most treatment options for a popliteal artery aneurysm are based on a number of factors which include an individual’s age, their overall health condition, their symptoms and the complexity of the intervention required. Typically most experts advise the repair of popliteal aneurysms greater than 3cm in diameter. The chances of success when treating an aneurysm are greatly influenced by the condition of the arteries and how much damage is caused by blood clotting.
A few treatment methods include:
- Surgery: In open surgery, the surgeon cuts the skin and tissue to reach the aneurysm directly. The aim is to eliminate the aneurysm from the circulation by tying off (ligating) the artery above and below the aneurysm.
There are two main approaches to this operation either from behind the knee (less common, posterior approach) or along the inside of the leg (more common, medial approach).
- Thrombolysis: A technique that is used to clear the arteries downstream from the aneurysm if they become blocked by blood clot when an aneurysm blocks off severely. This technique is used to reopen a blocked aneurysm and although it doesn’t treat the aneurysm, it can help clear up the arteries in preparation for the main treatment of the aneurysm.
- Endovascular techniques: A technique that involves placing a stent graft (tube) through the popliteal artery aneurysm in order to build a new pathway for blood flow to travel through. The blood will travel along the graft to the calf and foot. This helps to prevent the risk of a blood clot moving to and blocking the leg arteries, prevents rupture of the aneurysm, and avoids blockage of the knee artery.