Popliteal pulse is a common finding in patients with acute chest pain. The most common site of popliteal pulse is the right upper quadrant (PURQ).1,2 The term popliteal means “on the left side” and plexus means “a bundle or network.”3 Pneumothorax occurs when air enters the space between your lungs and outside the body through a collapsed lung.4 Chest wall collapse usually results from trauma such as a fall or other forceful movement.5 Pulmonary embolism occurs when blood clots travel into the space between your lungs and enter the bloodstream.6 If you have had a heart attack, pulmonary thromboembolism may occur if there are large amounts of platelets in your blood.7 Aortic dissection occurs when a small piece of an artery becomes detached from its main vessel.8
The popliteal pulse is located in the area where two veins meet at the top of your thighbone.9 You will often see it in patients with chest pain caused by a pneumothorax or rupture of a lung.10,11
In general, popliteal pulses are not painful unless they are very large or deep. Also, they are not usually visible to the naked eye. It is sometimes difficult to perform a popliteal pulse examination on very thin patients.12
If you feel a popliteal pulse, it means that you should carefully examine the other leg for unusual signs of trauma or injury. When feeling a popliteal pulse on one side, you should examine the other leg for symmetry or differences.
This is a guide on how to perform a popliteal pulse examination.
Start by placing your patient in a seated position or lying down on his or her back. Make sure that you have enough room to access the patient’s leg. When you feel the popliteal pulse, it should be done for a minimum of two full beats. You can use your first and second fingers to apply some pressure on the popliteal artery while you are feeling for the pulse. You should be aware of any pain or tenderness that may occur while you are feeling for the pulse.
Often times, a patient with an injury or condition involving blood flow to or from the leg will not have a popliteal pulse. If you suspect a spinal cord injury, but cannot find a popliteal pulse on one side, you should perform a carotid check; this involves placing two fingers on the side of the neck. Next, you should assess the patient’s capillary refill and motor-sensory testing. You should look for a carotid pulse by pressing your index finger and your thumb on the side of the neck. If you cannot find a carotid pulse after one minute of searching, it is best to send the patient to the emergency room immediately.
If the patient has a painful, swollen, red or black leg, you may suspect a popliteal artery obstruction or thrombosis. 13 You should also examine the feet and other leg for symmetry. You may want to inspect and palpate the foot and ankle for signs of frostbite. If there are no major signs of frostbite or injury, you should re-examine all areas at regular intervals. If a leg is tingling, painful, or numb, the patient should be referred to a physician immediately.14
Here is an example of how to assess a popliteal pulse:
Claudia is a 40-year-old woman who comes into your office complaining of left sided chest pain she says has been getting worse over the past few days. You auscultate her chest and hear crackles in her lower left lung. You palpate her chest wall and find that it is rigid. You suspect a tension pneumothorax. You ask her to bend forward and you feel a small (2 cm) spongy area in her upper back.
You shine a penlight on the area and see that it is indeed her left lung. You also see a round, 2cm red spongy area in her upper thigh, which you use your finger to compress. A large amount of blood quickly fills the popliteal space (the area behind her knee), and after releasing the pressure the blood disappears back into her leg. You diagnose a tension pneumothorax and perform a needle decompression.
CLINICAL PEARLS
The popliteal artery is the terminal continuation of the anterior and deepcommon iliac arteries. 1
The popliteal artery supplies most of the lower limb, except portions of the anterior and intermedial areas. 1
The popliteal artery can be palpated from the back, but it is usually easier to find it by putting your fingers behind the knee and moving them inward toward the body. 1
The popliteal pulse is equivalent to the pulse you find on the side of your neck (carotid). It can be felt by firmly pressing on the back of the knee. 2
A popliteal pulse is commonly checked by doctors to help assess blood flow through the leg and determine if there is any vascular narrowing. 3
The most important artery in the body is the one that you cannot live without, and that is the one that goes to your brain — the brain is a very greedy organ that needs a lot of oxygen, even when you are asleep. 4
The popliteal artery is located in the bulge behind the knee. It can be indirectly palpated by flexing and extended the knee and then firmly pressing on the bony prominence at the side of the joint. 5
Disorders of the popliteal artery are usually caused by blocked atherosclerotic plaques, which can lead to rest pain or subtler problems such as intermittent claudication. 6
Arteriosclerosis is the narrowing of the arteries due to the formation of atheroma (plaque) in the vessel wall. Atheroma is made up of cholesterol, calcium and other materials that make up the arterial wall. When atheroma occurs in the arteries of the legs, it most commonly occurs in the femorals, popliteal and tibial arteries. When atheroma occurs in the arteries of the arms, it most commonly occurs in the brachial and radial arteries. When atheroma occurs in the arteries of the neck, it most commonly occurs in the common, internal and carotid arteries.
Sources & references used in this article:
The utility and durability of vein bypass grafts originating from the popliteal artery for limb salvage by JL Mills, V Gahtan, RM Fujitani… – … journal of surgery, 1994 – americanjournalofsurgery.com
Clinical characteristics and outcome in 223 diabetic patients with deep foot infections by M Eneroth, J Apelqvist… – Foot & ankle …, 1997 – journals.sagepub.com
A Matter of Life and Limb: Get to Know Acute Limb Ischemia by EO Demand, I Awards – emsworld.com
Transmetatarsal amputations and arterial surgery in diabetic patients by FC Wheelock Jr – New England Journal of Medicine, 1961 – Mass Medical Soc
Acute peripheral arterial occlusion by MW Day – Nursing2019, 2004 – journals.lww.com
Calciphylaxis: What nurses need to know by DE Bliss – Nephrology nursing journal, 2002 – search.proquest.com
Blunt lower-extremity trauma and popliteal artery injuries: revisiting the case for selective arteriography by H Abou-Sayed, DL Berger – Archives of Surgery, 2002 – jamanetwork.com
Mitral Stenosis with Radial Pulse Difference by ED Friedman – Journal of the American Medical Association, 1916 – jamanetwork.com
